3

U s DEfT. OF Af K'CÜLIURE

I I B R A R Y

DEcaZ\mm ie«IAL RECORDS I

PUERTO RICATT

WOODS

Their Machining, Seasoning

and Related Characteristics

Agriculture Handbook No. 205

^•S. DEPARTMENT OF AGRICULTURE • FOREST SERVICE
PUERTO RICAN WOODS

Their Machining, Seasoning

and Related Characteristics

by

FRANKLIN R. LONGWOOD

Northeastern Forest Experiment Station, Forest Service;

formerly at the Tropical Forest Research Center

of the Forest Service in Puerto Rico

Growth Through Agricultural Progress

U.S. DEPARTMENT OF AGRICULTURE FOREST SERVICE

Agriculture Handbook No. 205 Issued November 1961
ACKNOWLEDGMENTS

Studies of the type described in the following pages require the cooperation

and assistance of many individuals and organizations. The writer was particularly fortunate in this regard and takes this opportunity to express his

appreciation to all those to whom he is indebted.

Special acknowledgment and thanks are due ßaul Coronado Ybarra and

Ernesto Goytia Olmedo for their indispensable assistance throughout the

study ; J. T. Drow, B. F. Kukachka, E. C. Peck, and E. L. Peterson of the U.S.

Forest Products Laboratory for their assistance in planning the research program, in computation of data, and manuscript review; E. M. Davis of the

Forest Products Laboratory for assistance in developing machining and

grading techniques; Dr. Elbert L. Little, Jr., for his careful technical review;

the Commonwealth Forest Service of Puerto Rico for supplying part of the

test material ; Dr. F. H. Wadsworth, Research Center Leader at Rio Piedras,

for his counsel and support ; Antonio Atiles of the University of Puerto Rico

Agricultural Extension Service for the many excellent photographs; and Dr.

G. N. Wolcott, Entomologist at the University of Puerto Rico Agricultural

Experiment Station, for conducting tests on the resistance of Puerto Rican

woods to dry-wood termites.
Contents

Introduction

PART 1

Determination of maciiining cliaracteristics and related properties

Selection of sample material

Air-seasoning characteristics

Procedure

Results

Tendency to warp

Procedure

Results

Physical properties ._

Specific gravity and moisture content

Weight per cubic foot

Shrinkage

Machining properties

Procedure

Selection of test material

Grading

Planing

Shaping

Turning

Boring

Mortising

Sanding

Related properties

Screw splitting

Resistance to dry-wood termites

Summary and conclusions

PART 2

Timber descriptions

Achiotillo

Aguacatillo

Algarrobo

Almacigo

Almendra

Ausubo

Caimitillo

Caimitillo verde

Caoba hondurena

Capá blanco

Capá prieto

Caracolillo

Casuarina

Cedro hembra

Ceiba

Page

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30

31

35

35

36

36

38

39

39

40

41

42

43

44

45

46

47

48

Page

Timber descriptions—Continued

Cucubano 49

Cup ey 50

Espino rubial 51

Eucalipto 52

Granadino 53

Guaba 54

Guajón 55

Guama 56

Guano 57

Guaraguao 58

Guayabota 59

Higüerillo 60

Jácana 61

Jagua 62

Jagüey blanco 63

Jobo 64

Jusillo 65

Laurel amarillo 66

Laurel avispillo 67

Laurel geo 68

Laurel prieto 69

Laurel sabino 70

Mago 71

¡Mamey 72

Mango 73

María 74

Maricao ^ 75

Masa 76

Moca 77

Motillo 78

Negra lora 79

Nemocá 80

Nuez moscada 81

Palo colorado 82

Palo de hueso 83

Palo de matos 84

Panapén 85

Roble blanco 86

Samán 87

Tabaiba 88

Tabonuoo 89

Teca 90

Ucar...^ 91

Yagrumo hembra 92

Yagrumo macho 93

Bibliography 95

Index to timber descriptions 97

m

For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington 25, D.C. Price 65 cents
INTRODUCTION

More than 500 species of trees are indig-enons to

the forests of Puerto Eico, raiigiiiQ- from Ijalsa,

which produces the lightest commercial wood

known, to lignumvitae, one of the heaviest and one

of the most valuable of all woods. Yet fewer than

one-third of these tree species ordinarily reach

saw-log size. Moreover, only 52 of this number,

plus 8 introduced species, provide the bulk of all

native-grown saw-log size material available for

domestic and conunercial use. The others either

mature below saw-log size or occur too infrequently for commercial use. A few high-quality

woods owe their scarcity and small size to past

heavy cutting because of their good qualities.

Still others are seldom used because they are difficult to season or machine or their properties

and uses are poorlj' known. This does not preclude the possibility that other species will become

merchantable when more is known about their

characteristics and uses.

Most of the native woods are available only

in limited quantities and none are sufficiently

abundant for export. Nevertheless, many of

them have far more utility and value than their

current use would indicate.

At present fewer than a dozen of these tree

species are utilized to any appreciable extent for

lumber and similar products. The majority either

are not used at all or are used principally for

fuel, charcoal production, or other low-value

products.

This improvident use of a relatively scarce resource cannot be attributed to a lack of markets

for wood. Every year some 80 to 90 million board

feet of lumber and other wood products are required to meet the expanding requirements of the

island. About 1 percent of this volume, some

850,000 board feet, is provided by the local forests :

the remainder is imported from the United States,

Mexico, and other Caribbean areas. Immense

quantities of low-grade but relatively expensive

pitch pine and western fir are brought in annually,

yet are inferior in some ways to a number of

virtually unused native woods.

^ Relatively little is known about the characteristics and properties of the local woods or the uses

for which they are suitable. This is in contrast to

'Additional Information abont nearly all these tree

species, ineludins de.'icriptions, drawings, ranges, and

other common names, is included in the following

puhlication :

Little, Elbert L., .Tr., Wad.sworth, Frank H., and

Marrero, .losé. Arboles Communes de Puerto Rico e

Islas Vírgenes, university of Puerto Rico. (in

press. )

the relatively detailed and complete knoAvIedge

about the iniported woods. Probably no other

factor contributes moi-e toward the neglect and

misuse of native woods.

Another factor contriljuting to rlie neglect of

native woods is the erroneous but nevertheless

widesi)read belief tliat only lieavy, dark-colored

woods are strong and durable, machine well, or

posses artructi\'e figure. Both Honduras mahogniiv and i-edro hembra illustrate the fallacy of

this ideii. Altliough moderately light in color and

wejgiit, hotli woods are rated among the all time

favorites for cal:)inetmaking and other exacting

uses. Furthermore, most of the imported woods,

especially pitch pine, western fir, baboen, and

African mahogany, are also light in weight and

color l)ut nevertheless liave good utility for a multitude of uses.

The utility of Puerto Pican woods is frequently

depreciated by a combination of improper seasoning, poor handling, and unsuitable machining

practices. This condition results not so much

from neglect or unwillingness to employ proper

practices but rather from a scarcity of knowledge

in these fields. Lack of information concerning

the drying, handling, and machining properties of

these woods has been an obstacle to wider use.

Some of the everyday operations in utilizing local

woods have been under investigation at the Tropical Research Center for several years. This handbook summarizes the infonnation that should be

useful to the person using or contemplating the

use of native woods for domestic or commercial

purposes.

The material presented is divided into two

parts: Part 1 describes the procedures and summarizes the results of recent determinations of

wood properties at the Tropical Forest Research

Center in Rio Piedras, Puerto Rico. Of the principal saw-log; species of Puerto Rico, 56 were included in the tests, along with plantation-grown

teak, eucalyptus, and casuarina. Forest-grown

Honduras mahogany from ^Mexico, also planted

extensively on the island, was included for comparison. These native species and planted exotics

(table 1) represent the bulk of all saw-log-size

limiter growing on the island.^

Fourteen of the 60 woods as well asa few others from

Puerto Rico are described further in the following

publication :

Longwood, Franklin R. Present and Potential

Timbers of the Caribbean—With Special Reference to

the West Indies, the Ouianas, and P>ritish Honduras.

U.S. Dept. Agr. Handbook No. 207. 1961.
U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

TABLE 1.—The priiicipal native and jilantation-grovn navi-log loooeh of Puerto Rico

Common name in Puerto

Rico

Achiotillo

Aguacatillo

Algarrobo

Almacigo " Almendra ' ^

Ausiibo

Caimitillo

Caimitillo verde—

Caoba hondurena ^

Capá blanco '

Capá prieto '

Caracolillo

Casuarina ^ 3

Cedro hembra

Ceiba

Cucubano

Cupey

Espino rubial

Eucalipto 1 ^ '

Granadino

Guaba ^

Guajón

Guama

Guano

Guaraguao

Guayabota

Higüerillo '

Jácana

Jagua

Jagüey blanco

Jobo

Jusillo

Laurel amarillo

Laurel avispillo

Laurel geo

Laurel prieto

Laurel sabino

Mago

Mamey '

Mango 2

María

Maricao

Masa

Moca

Motillo

Negra lora

Nemocá

Nuez moscada

Palo colorado

Palo de hueso

Palo de matos

Panapén ^

Roble blanco

Samán 12

Tabaiba

Tabonuco

Teca 2 3

Ucar '

Yagrumo hembra_.

Yagrumo macho.__

Scientific name

Alchornea latifolia Sw

Meliosvia herberlü Rolfe

Hxjmenaea courbarü L

Bursera simaruha (L.) Sarg

Terminalia catappa L

Manükarahidentata (A. DC.) Chev

Micropholis chrysophylloides Pierre

M. garciniaefoUa Pierre

Swietenia macrophylla King

Petitia domingensis Jacq

Cordia alliodora (Ruiz & Pav.) Oken

Homalium racemosuni Jacq

Casuarina equiselifolia L

Cedrela odorala L

Ceiba pentandra (L.) Gaertn

Guetiarda laevis Urban

Clusia rosea Jacq

Zanthoxyhnn marlinicense (Lam.) DC

Eucalyptus robusta J. E. Smith

Buchenavia capiiaia (Vahl) Eiehl

Inga vera Willd

Beilschmiedia péndula (Sw.) Benth. & Hook, f

Inga laurina (Sw.) Willd

Ochroma pyramidale (Cav.) Urban

Guarea trichilioides L

Eugenia stahlii (Kiaersk.) Krng & Urban

Vitex divaricata Sw

Pouteria multiflora (A. DC.) Eyma

Genipa americana L

Ficus laevigata Vahl

Spondias momhin L

Calycogonium squamulosiim Cogn

Nectandra sintenisii Mez

N. coriácea (Sw.) Griseb

Ocoiea leucoxylon (Sw.) Maza

Nectandra memhranacea (Sw.) Griseb

Magnolia splendens Urban

Hernandia sonora L

Mammea americana L

Mangifera indica L

Calophylhim brasiliense Camb

Byrsoniina coriaceum (Sw.) DC

Telragastris balsamifera (Sw.) Kuntze

Andira inermis (W. Wright) H.B.K

Sloanea berteriana Choisy

Matayba domingensis (DC.) Radlk

Ocotea spathulata Mez

O. moschata (Meissn.) Mez

Cyrilla racemiflora IJ

Haenianihus salicifolîus Griseb

Ormosia hrugii Urban

Artocarpus altilis (Parkinson) Fosberg

Tabebuia heterophylla (DC.) Britton__

Pithecellobium saman (Jacq.) Benth

Sapiuin laurocerasus Desf

Dacryodes excelsa Mahl

Tectona grandis L. f

Bucida huceras L

Cecropia peltata L

Didymopanax morototoni (Xubl.) Dec. & Planch

English name

West Indian locust, courbaril.

Gumbo-limbo.

Indian-almond.

Balata, bulletwood.

Honduras mahogany, Mexican

mahogany.

Capa.

Casuarina.

Spanish-cedar, Central American cedar.

Silk-cotton tree.

Martinique prickly-ash

Beakpod eucalyptus.

Balsa.

American muskwood.

White fiddlewood.

Genipa.

Shortleaf fig.

Yellow mombin.

Jamaica nectandra.

Mango.

Mamey, mammee-apple.

Santa Maria.

Cabbage angeUn, angelin.

Swamp cyrilla.

Breadfruit.

"White-cedar."

Rain-tree.

Candlewood, gommier.

Teak.

Oxhorn bucida.

Trumpet-tree.

Matchwood.

' Sample material Hunted to 2 or 3 sauiril- IOP-^

2 Introduced species. ' '" Plantation grown.
PUERTO RICAN WOODS

The tests of the 60 species included determinations of specific gravity and weight per cubic

foot, shrinkage, seasoning characteristics, machineability, and resistance to dry-wood termites.

The density and shrinkage values are based on

well-prescribed conditions and procedures which

can be repeated. These data then are significant

for each species. The opposite is true for the

other tests, in which seasoning conditions, macliining techniques, and other factors aifect the

numerical ratings of the different species. In

these tests, the comparative ratings of the different woods are more important that the numerical grades assigned on the basis of the test results.

Certain other characteristics or properties, such

as stability after manufacture, weathering characteristics, permeability to preservatives, and durability in or near the ground, are also important

in certain uses but were not considered in the

study. The purpose of this series of tests was to

provide a broad general knowledge of certain important characteristics of the principal lumber

species.

The study was not intended to develop detailed

and complete knowledge of the different aspects

of the uses of the different woods but rather to

evaluate some of their more important properties

so that the potential producer or user can either

grow or utilize them more efficiently. It is only

a beginning; much more needs to be done before

the different woods can be most efficiently utilized

in the local economy.

Part 2 contains a brief summary of the important characteristics and properties of the same

60 timbers of potential importance in Puerto Rico.

Figures showing representative plainsawed and

quartersawed sections are also included for each

species.^

Timber descriptions are based on the tests described in Part 1, and on other observations made

over several years at the Wood Testing Laboratory in Rio Piedras. Physical descriptions of the

tinibers are based on the average for several hundred specimens prepared in the laboratory from

trees cut in the local forests. Information on conversion, seasoning, green and air-dry ^ weight,

shrinkage, machining properties, and certain insect and fungous enemies was derived from tests

and observations in the Laboratory. This was

supplemented by local knowledge of the trees and

their woods and a limited amount of reference

material. Data on resistance to dry-wood termites was provided by Dr. G. N. "Wolcott of the

University of Puerto Rico from results of previous research, and from current studies using

wood specimens prepared at the Wood Testing

Laboratory.

Recommended uses are listed for each species

on the basis of its physical and mechanical characteristics. Since a number of the woods appeared to be comparable to other well-known

woods, they were recommended for similar uses.

Wherever possible, acceptable local uses are also

shown for those species currently being utilized.

This information is supplemented by listing current uses for those species or for other closely related species growing in other areas of the Caribbean. In some instances, recommendations by

relial)le sources outside the Caribbean area were

included, but only if they conformed with the

known characteristics of the wood. Additional

research and experience with the different species

will undoubtedly add many specific uses to those

mentioned in the text.

'Photographs were taken and processed by Antonio

Atiles of the University of Puerto Rico Extension Service,

using specimens prepared at the Wood Testing Laboratory in Rio Piedras.

' All air-dry weights were calculated on the basis of 15

percent moisture content.
PART 1. DETERMINATION OF MACHINING

CHARACTERISTICS AND RELATED PROPERTIES

Selection of Sample Material

All sample material required for determinations

of shrinkage, specific gravity, air seasoning, machining properties, and screw splitting, was taken

from one set of sample logs for each species. Except as noted, all sample material was obtained

from five or more typical saw-log-size sample

trees of each species. These trees were selected at

random from the local forests or plantations.

One sample log, 9 feet 6 inches long, was cut

from each sample tree, starting at a point 8 feet

above the butt swell. For certain species that

normally have clear boles less than 16 feet long,

the sample logs were cut from the center of the

merchantable part of the trees. The first 8-

foot section of some sample trees was also selected for use in the machining and air-seasoning

tests when insufficient volume was available in the

regular sample logs. These are referred to as

lumber logs.

The logs were ñatsawed into random-width lumber in a small circular sawmill. Boards were supposed to be cut 1% inch,thick, but were more often

ll^ inch thick because of the extremely poor condition of the mill. Six sample boards were selected from each sample log during sawing.

Four of these were typical flatsawed boards 4

inches or more wide, one from each of the four

quadrats of the log, for use in specific gravity

and shrinkage tests. One board was taken from

the periphery, one near the pith, and two from

the area of representative or average growth. In

addition to the above, two 8V2-inch boards were

selected from opposite quadrats of each sample

log for use later in warp tests.

The lumber logs cut from the butt sections of

some trees were sawed into flat-grain lumber in

the same manner as the sample logs but no sample

boards were selected. The selection and preparation of the lumber and test material for the various tests and the procedures followed in these

tests are described in the later sections dealing

with the individual subjects.

Air-Seasoning Characteristics

Lumber and other wood products cut from saw

logs are generally kiln-dried or air-seasoned prior

to use. The time required for seasoning and the

type and severity of defects occurring during the

process vary greatly among woods and are of primary importance in their utility. A wood may be

attractive and may possess very satisfactory machining and mechanical characteristics, yet it may

have limited use because of poor seasoning characteristics. Other things being equal, woods that

season readily and with a minimum of degrade

are preferred. With good control, most woods

can be kiln-dried with less degrade than occurs

in air-seasoning. However, lumber generally is

partially air-seasoned before it is put into'the

kiln. Considerable warping and checking in the

preliminary air-seasoning are sometimes improved

during the kiln-drying process. Consequently,

the air-seasoning characteristics of a wood are impoitant whether it is to be kiln-dried or seasoned

only in the open.

Tlio tests involved two parts; one was a study

of the time required to air-season conventionally

piled green lumber and of the type and frequency

of defects occurring during the process ; the other

was a warp-test study in which 4-foot boards were

allowed to season without restraint of any kind

so that the natural warping tendencies of the

différent woods could be observed and measured.

PROCEDURE

Preparation of Lumber

Lumber used in the air-seasoning tests was typical random-width commercial-quality flat-grain

boards, 1% inches to I14 inches thick and 8 feet 2

inches long. All material was first end-trimmed

to exact size and then dipped for 3 minutes in

an aqueous solution containing benzene hexachloride and a mild fungicide to prevent insect

attack and development of molds and sap-staining

fungi. After dipping, the boards w^ere end-coated

and piled under cover for air-seasoning. All defects evident in the boards at the time of piling

were marked to distinguish them from defects

developing during seasoning.
PUERTO RICAN WOODS

P-495305

FIGURE 1.—Puerto Rican woods stacked for air-seasoning at the Wood Testing Laboratory in Rio Piedras, Puerto Rico.

The lumber was seasoned on specially prepared

pile foundations in sheds open on three sides and

partially open on the fourth side. The pile foundations, 6 feet wide by 8 feet 2 inches long, were

built on cement-block supports. Supports were

centered at 2-foot intervals in 3 rows running the

length of the pile, requiring 15 supports for each

pile (fig. 1). Six-inch square timbers were placed

on the 3 tiers of supports lengthwise and 4- by

4-inch cross members positioned over them at 2-

foot intervals. Piles were spaced 4 feet apart to

allow adequate air circulation and working space.

This type of foundation meets the accepted standards for good air-seasoning practices. None of

the subsequent warpage was attributed to faulty

pile foundations.

Stacking Lumber

The lumber was piled as shown in figure 1,

leavmg Vg-inch spacing between boards up to 81/,

inches wide and 1-inch spacing between wider

°ff-. pry softwood stickers, 25/3^ inch thick

and 1% inches wide, were placed between each

layer of boards at 24-inch inter\'als directly above

the pile supports and cross members. Piles were

stacked 8 feet high. They were topped oif with

surplus lumber and anchored in place with 300 to

400 pounds of concrete weights.

Determination of Moisture Content

To record the drying rate of each species, it

was necessary to determine the moisture content

at the start of drying, at frequent intervals during

the seasoning process, and finally when the lumber

Avas air-dry. For this, six sample boards, predominantly heartwood, were prepared for each

species. These samples, 19 inches long, were cut

from the center of green boards, and a wafer

approximately I14 inches long was sawed from

each end for determining their initial green moisture content and ovendry weight.

The 16-inch samples were then end-coated with

plastic-asphalt roof coating, weighed to the nearest 2 grams, and placed in the lumber piles on

specially prepared cradles (fig. 2).
6

U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 205

These pile samples were removed from the lumber stacks at 2-week intervals, weighed, and returned to the piles. The moisture content of each

sample was calculated each time, according to the

following formula :

Moisture content in percent=

current weight—calculated ovendry weight ^ ^^^

calculated ovendry weight

When no loss was recorded over a 4-week period,

the samples were considered to have been air-dry

at the start of the 4-week period. A final check

on the air-dry moisture content was then calculated by means of five or more cross sections cut

from each pile sample.

Measurement of Drying Defects

After each wood became air-dry, 50 or more

air-dry boards were inspected for the presence

* Forest Service. Wood Handbook. U.S. Dept. Agr.

Handb. 72, 479-490. 1955.

and severity of warping and checking that had developed during seasoning. Seasoning defects

were rated on this basis : A = none, B =very slight,

G = slight, D =moderate, E = severe, and F= very

severe.

The use of badly warped lumber requires increased labor, and it causes waste in manufacture.

Warp may also cause trouble later. Warped

boards usually require heavy planing or must

be cut into short or narrow pieces, or both.

Warp was separated into four categories: cup,

twist, crook, and bow. The first two are the most

serious. Cup is defined as "a deviation flatwise

from a straight line across the width of the

board" ; twist is "a distortion caused by the turning or winding of the edges of a board so that

the four corners of any face are no longer in the

same plane"; bow is "the distortion in a board

that deviates from flatness lengthwise but not

across its face"; crook is "a distortion of a board

in which there is a deviation edgewise from a

straight line from end to end of the board." *

FIGURE 2.-

F-495310

-Sample boards fur determining tlie moisture content of stacked lumber were placed in the stacks in specially

fitted cradles.
PUERTO RICAN WOODS

Checking may occur either on the surface of

boards or at the ends. It may be superficial and

easily removed during planing or trimming, but it

may be so deep as to make the piece worthless.

RESULTS

Seasoning Time and Final

Moisture Content

Most of these woods were thoroughly airseasoned in 6 months or less, some requiring only

3 to 4 months and others 10 months or longer.

Table 2 shows the approximate number of weeks

required to air-season the different woods and the

final air-dry moisture content reached when 1 /gto 114-inch lumber is piled for seasonmg under

cover in the San Juan area. These figures represent the average for each wood, and they vary

slightly according to the density of individual

pieces of a species; particularly, dense specmiens

of any wood will normally have a somewhat lower

moisture content than those that are lighter than

average. The final air-dry moisture content

values range considerably among the different

woods, from a low of 16 percent for seven different woods to a high of 22 percent for mamey. In

comparison, thoroughly air-dry Honduras

mahogany used in the machining tests contained

an average moisture content of 16 percent.

TABLE 2.—Approximate time to air-season green i%- to ly^^-inch rotigh lumber in San Juan^ Puerto Rico

RAPID

Species

Guaba

Caimitillo verde..

Almendra

Yagrumo hembra

Yagrumo macho _

Laurel sabino

Granadino

Roble blanco

Nuez moscada—

Masa

Capá blanco

Cedro hembra

Caimitillo

Ausubo

Tabonuco

Guama

Teca

Espino rubial

Mago

Almacigo

Time to

season

Weeks

11

12

13

14

14

14

15

15

15

15

15

16

16

16

16

17

17

17

17

17

Final

moisture

content

Percent

19

18

18

17

16

17

18

17

18

17

18

20

17

19

17

18

17

18

17

18

Species

Guano

Ceiba

Nemocá

Samán

Eucalipto

Güayabota

Algarrobo

Jusillo

Cucubano..

Laurel amarillo

Laurel avispillo

Laurel prieto..

Ucar

Caracolillo

Cupey

Palo de hueso..

Jobo

Tabaiba

Maraicao

Time to

season

Weeks

22

23

23

23

24

24

25

25

25

25

25

25

25

26

26

26

26

26

26

Final

moisture

content

Percent

17

18

17

17

19

18

17

18

18

17

17

16

17

18

17

17

16

17

16

MODERATE SLOW

Casuarina... 19

19

19

19

20

20

20

20

22

22

18

16

22

19

17

17

17

19

16

18

Jagüey blanco

Palo de matos

27

27

27

29

29

30

31

41

45

52-1-

17

Laurel geo 16

Mamey. .. María

Jáeana

Negra lora

Jagua - -. --

18

Mango. 17

Achiotillo.. 19

Aguacatillo 20

Moca 19

Panapén Palo colorado 19

Motillo Ouaión 20

Capá prieto..

Required more than 1 year to air-dry under test conditions.
8

U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

Some variations in the final air-dry moisture

content values occur during different parts of the

year in the San Juan area. Consequently, the

moisture contents presented in table 2 are approximate and may vary for some woods as much

as 3 to 4 percent according to season. However, it

is evident that most Puerto Rican woods will airseason to between 16 and 19 percent in the San

Juan area. In general, it should be safe to assume

that lumber is air-dry in the San Juan area when

all samples show 18 percent or less moisture content. The additional shrinkage between this point

and the lower moisture content reached by some

woods will have little effect on their utility in

service.

Seasoning would be more rapid and the final

air-dry moisture content somewhat lower in the

dry climate prevailing along the south side of the

island than in the San Juan area on the north

coast, where these tests were conducted. The opposite conditions would occur in the humid mountain regions of the interior where it is nearly impossible to season lumber without protection from

the heavy and frequent rainfall, which may reach

200 inches annually at the higher elevations. It

is probably impractical to air-dry lumber under

these conditions.

In addition to climate, the method of piling and

the amount of ventilation has considerable effect

on the rapidity of air-seasoning. In this study

the woods were seasoned under conditions that

were considered normal for the area. However,

closer piling and less ventilation probably would

have retarded the rate of seasoning and, as a result, would have reduced the amount and severity

of surface checking. But warping would not have

been materially changed. Conversely, more open

piling and increased air movement probably would

have reduced the drying time and increased

checking.

The proximity of one species to another in the

]3Íles, or its location within the pile, may have

influenced the drying rate of some woods. And

the season when the wood is di'ied may be of even

greater importance.

Seasoning Degrade

A summary of the degrade occurring in the

different woods as a result of seasoning uncler the

test conditions is i^resented in table 3. All but 13

of the woods seasoned satisfactorily, 17 with only

minor degrade, and 29 with a moderate but acceptable amount of degi'ade. For most purposes,

the woods in class 1 and 2 ai'e quite acceptable for

commercial use. But those in class 3 could probably be imj^roved by slower seasoning.

]\Iost of the degrade occurred in the form of bow

and twist whereas cup and crook was of minor

importance in most woods. With the exception of

mamey, casuarina, and palo colorado, surface

checks and end splitting during seasoning were

not serious. The amount of end splitting was

undoubtedly reduced by the use of end coatings.

However, the application of end-coating material

is recommended when seasoning hardwoods and

is considered a common practice.

TABLE 3.—Rating of Puerto Rican woods for degrade occurring during air-seasoning of -?%- to ly^^-inch

rough lumber ^

CLASS 1—MINOR DEGRADE

Species

Warp

Cup Bow Twist Crook

Checks and splits

Surface End

Almacigo

Ausubo

Caimitillo

Cedro hembra

Guajón

Granadino

Higüerillo

Jagua

Jagüey blanco.

Laurel prieto..

Laurel sabino.

Mago

Mango

Masa

Nuez moscada

Tabonueo

Teca

B

B

A

B

B

A

B

B

B

B

A

B

B

A

B

B

B

B

C

B

B

C

B

C

C

c

c

B

C

C

B

C

C

c

c

B

A

B

B

B

C

C

C

B

C

C

C

B

B

C

B

A

B

A

A

B

A

B

B

B

B

A

B

B

A

B

A

B

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

B

A

A

A

A

A

A

A

B

B

B

See lootnotes at end ot table.
PUERTO RICAN "WOODS

TABLE 3.—Rating of Puerto Rican woods for degrade occurring during air-seasoning of iy%- to ly^-mch

rough lumber '—Continued

CLASS 2—MODERATE DEGRADE

Species

Achiotillo

Almendra

Caimitillo verde

Capá blanco

Capá prieto

Caracolillo

Ceiba

Cucubano

Cupey

Guaraguao

Guaba

Guama

Guano

Guayabota

Jobo

Jusillo

Laurel amarillo.

Laurel avispilloMaricao

Moca

Motillo

Negra lora

Nemocá

Palo de hueso-_

Palo de matos_-

Panapén

Roble blanco

Tabaiba

Ucar

Warp

Cup Bow

c C-D C

B D c

B C-D c

B D D

B D C

B D C

C C C

C C C

C C D

C D C

A D B

A D B

C-D C C

C c D

B D C

B D C

B D c

D c c

B D c

B D A

G C-D c

C C D

B D C-D

B D c

C D c

C D c

A D B

C D B

B C-D c

Twist Crook

B

C

B

A

B

B

B

B

C

B

A

B

B

B

C

B

B

C

C

A

B

G

D

B

B

C

A

B

B

Checks and splits

Surface

B

A

A

A

A

B

D

D

C

A

A

A

B

C

B

B

A

A

B

A

D

D

B

C

B

A

A

C

C

CLASS 3—CONSIDERABLE DEGRADE

Aguacatillo

Algarrobo

Casuarina

Espino rubial

Eucalipto

Jáoana

Laurel geo

Mamey

María

Palo colorado

Samán

Yagrumo hembra ^

Yagrumo macho...

E

D

E

B

D-E

D

D

E

D

F

B

D

D-E

D

D-E

D-E

D

D

D

D

D

E

F

D-E

D-E

D-E

C-D

D-E

D-E

D

D-E

D

D

E

E

F

C

D-E

D

D

D

B

D

C

B

D

D

E

F

D-E

D

D

D

D

E

B

B

D

A

E

A

F

A

A

A

' Severity of defects are coded as follows:

A—None D—Moderate

B—Very slight E—Severe

C—Slight F—Very severe

The frequency and severity of defects causing

degrade, particularly those causing surface

cliecking, are often increased by overrapid drying.

Ihis can be prevented by closer piling, less ventilation below, above, and around the piles, and by

using thinner stickers. Some warp may have been

2 Subsequent tests indicate that yagrumo hembra can

be air-dried with only moderate degrade under what may

have been more favorable conditions.

caused by the "thick and thin" nature of the lumber, which complicated piling. However, this

condition is not unusual in material sawed in small

sawmills, and it was accepted as a condition that

will usually prevail whenever rough lumber is

seasoned.
10 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 205

Tendency to Warp

PROCEDURE

The inhei^ent tendency of a wood to warp is^ an

important factor in the clegrade that occurs during

seasoning and in stability and beliavior of the

wood after manufacture. Woods liaving an inherent tendency to warp will generally incur more

degrade during seasoning, and may warp in use.

To determine this tendency for each wood, 10 or

more 4-foot lengths of fi/g inch thick green lumber

6 to 9 inches wide Avere end-racked and allowed to

air-season to efjuilibrium with the surrounding

atmosphere (fig. 3). This method permitted the

test samples to warp without restraint.

,^^^^'^

FiGUEE 3.—Four-foot boards end-racked for drying, a test of tendency to warp.

After becoming air-dry, the boards were placed

on a flat surface and measured for bow, cup, and

twist. A long Avedge (fig. 4), calibrated so that

each small division on the hypotenuse represented

a vertical distance of 0.01 inch from the adjacent

divisions, was used in the measuring. The amount

of warp was read in hundredths of an inch at the

worst point, because the maximum defect in any

piece determines the amount of waste dui-ing

manufacture. These readings were averaged for

the 10 or more samples for each species.

Results of the warp tests may be< useful as a

guide in pointing out the need for selecting seasoning techniques that will overcome or at least

reduce the inherent tendencies of certain woods

to distort during air-drying.

RESULTS

The comparative ratings of the woods in the

warp test (table 4) are in reasonably close agreement with results obtained in the air-seasoning

study, although some differences are apparent

between the two tests. Some Avoods showing a

tendency to undergo severe distortion in the warp

tests seasoned with only moderate degrade during

air-seasoning. How^ever, others showing up

poorly in the warp tests were also subject to moderate to heavy degrade Avhen air-seasoned.

Two tentative conclusions can be draAvn from

these results: (1) warp tests reveal the inherent

tendencies of the different woods to distort during

seasoning; and (2) the tendency of any wood to
PUERTO RICAN WOODS 11

^.j:. ! :■■ !-'''' ^'■■""'' '"'''^''

Jllllili).!'"!"""'

FIGURE 4.—Calibrated wedge used to measure warp.

B^-495312

distort during seasoning is, to some extent, overcome by proper seasoning practices in the airdrying tests. It is well known that piling boards

so that they are under restraint is effective in

reducing cup, twist, and bow. Similarly, piling

lumber in a way that will reduce the rapidity of.

drying will also reduce surface tension and the

accompanying checking and distortion.

TABLE 4.—Ttoist, cup, and how occumng in hardiooods when air-dried loithout restraint, arranged in

order from loorst to best ^

Species

Palo colorado

Mamey

María

Casuarina

AguacatilloEucalipto

Panapén

Yagrumo macho.

Algarrobo

Cupey

Maricao

Yagrumo hembra

Jácana

Jusillo

Nuez moscada

Ceiba

Laurel avispillo__

Jagüey blanco

Guano

Jagua

Palo de hueso

Guayabota

Almacigo

Nemocá

Mago

Ucar

Guajón

Espino rubial

Cedro hembra

Mango

Twist Cup

Inch Inch

3. 009 0. 365

. 997 . 273

. 473 . 057

. 271 . 094

. 225 . 139

. 206 . 175

. 271 . 106

. 266 . 104

. 109 . 072

. 194 . 056

. 094 . 044

. 197 . 087

. 191 . 050

. 196 . 008

. 118 . 056

. 188 . 101

. 107 . 066

. 124 . 040

. Ill . 114

. 150 . 043

. 120 .030

. 135 . 080

. 146 . 044

. 158 . 032

. 149 . 045

. 137 . 018

. 104 . 049

.070 . 042

. 070 . 032

. 054 . 039

Bow

Inch

0. 599

. 230

. 201

. 193

. 170

. 142

. 105

. 087

. 265

. 166

. 248

. 100

. 127

. 164

. 190

. 074

. 186

. 189

. 126

. 158

. 201

. 135

. 149

. 136

. 128

. 160

. 149

. 180

. 167

. 171

Species

Caimitillo verde

Cucubano

Achiotillo

Caimitillo

Laurel prieto

Laurel sabino. .

Palo de matos _-

Jobo

Motillo

Capá blanco

Samán

Guaba

Caracolillo

Almendra

Laurel geo

Masa

Guama

Laurel amarillo.

Capá prieto

Moca

Negra lora

Ausubo

Tabonuco

Roble blanco

Guaraguao

Tabaiba

Teca

Granadino

Higüerillo

Twist Cup

Inch

0. 112

. 126

. 092

. 077

. 105

. 104

. 080

. 063

. 085

. 063

. 063

. 038

. 074

. 090

. 048

. 063

. 032

. 061

. 045

. 043

. 069

. 037

. 073

. 022

. 054

Inch

0. 051

. 035

. 039

. 015

. 034

. 045

. 024

. 027

. 034

. 027

. 019

. 044

. 030

. 044

. 040

. 030

. 031

. 014

. 027

. 056

. 198

. 046

. 046

. 028

. 035

Bow

. 017 .032

. 042 . 006

.033 . 019

. 014 . 039

Inch

0. 084

. 099

. 114

. 153

. 101

. 050

. 132

. 143

. Ill

. 132

. 136

. 136

. 113

. 183

. 128

. 121

. 142

. 124

. 122

. 100

. 090

. 106

. 064

. 129

. 087

. 126

. 086

. 066

. 083

Based on 1- by 7-inch by 4-foot boards, adjusted to 7-inch width where necessary.
12 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

Physical Properties

SPECIFIC GRAVITY AND

MOISTURE CONTENT

Specific gravity is a fairly reliable indicator of

both the strength and machinability of wood. In

general, heavy woods are stronger and machine

better but with somewhat more difficulty than

lightweight woods. However, a number of exceptions to this were found in tests of machining

properties; some lightweight woods machined

better than others of greater density.

Specific gravity is used to express the relative

weight of wood. Technically, specific gravity is

the ratio of the weight of a given volume of wood

to that of an equal volume of water. Inasmuch as

the weight of a given volume of wood changes

with shrinkage or swelling caused by changes in

the moisture content, specific gravity is an indefinite value unless the conditions under which it is

obtained are specified.

Procedure

Specimens for determining specific gravity,

weight per cubic foot, moisture content, and

shrinkage were cut from the four sample boards

selected from each sample log as described previously. Cross sections were cut from the center

and one or both ends of the sample boards after

trimming had removed any part that may have

lost moisture during conversion. The cross sections were then planed to a uniform thickness of

^ The point at which the cell walls are saturated with

water but no free water remains in the cell cavities.

Generally this is at about 30 percent moisture content.

1.0 inch, and test specimens were prepared with a

smooth-cutting table saw. Most specimens measured 1.0 inch along the radial plane, 2.5 inches

along the tangential plane, and 4 inches on the

longitudinal plane. Specimens were selected to

be truly flat grained, but a nominal slope of the

growth rings characteristic of good-quality flatsawed boards was allowed.

Immediately after cutting, the specimens were

weighed to the nearest %o gram and the three

dimensions were determined to the nearest i/iooo

inch. A specially adapted dial micrometer was

used for these measurements (fig. 5). The specimens were weighed and measured again when airdry and again finally after being placed in an oven

at 103° C. until ovendry. The data on specific

gravity, shrinkage, and weight per cubic foot

(tables 5, 6, and 7) were computed from the

weights and measurements of these specimens.

Results

Table 5 shows the specific gravity for each

species, based on three different conditions: (1)

green volume and ovendry weight; (2) air-dry

volume at 15 percent moisture content and ovendry

weight; and (3) ovendry volume and ovendry

weight. The gravity data based on ovendry

volumes and weights is termed "true" specific

gravity, because it represents conditions that may

occur simultaneously. The other two specific

gravities are based on conditions that could not

occur simultaneously. These so-called "nominal" specific gravities are useful in computing the

true specific gravities at any moisture content

above the fiber saturation point ^ and below the

FIGURE .5.—Dial m ci-ometer adapted for measuring wood specimens to determine shrinkage and specific gravity
PUERTO RICAN WOODS 13

fiber Saturation point when the shrinkage rate is

loiown. The true air-dry specific gravity for any

moisture content beloAv 30 percent may also be

determined by the application of the factor m

column 6 of table 5.

TABLE 5.—Specific gravity of green, air-dry, and ovendry loood

Species

(1)

Moisture

content of

green wood

(percent)

(2)

Specific gravity based on ovendry

weight and—

Green

volume

(3)

Air-dry

volume 1

(4)

Ovendry

volume

(5)

Factor for

adjusting

specific

gravity ^

Achiotillo

Aguacatillo

Algarrobo

Almacigo

Almendra

Ausubo

Caimitillo

Caimitillo verde

Capá blanco

Capá prieto

Caracolillo

Casuarina

Cedro hembra

Ceiba

Cucubano

Cupey

Espino rubial

Eucalipto

Granadino

Guaba

Guajón

Guama

Guano

Guaraguao

Guayabota

Higüerillo

Jácana

Jagua

Jagüey blanco

Jobo

Jusillo

Laurel amarillo

Laurel avispillo

Laurel geo

Laurel prieto

Laurel sabino

Mago

Mamey

Mango

María

Maricao

Masa

Moca... _ _

Motillo \\\

Negra lora

Nemocá

Nuez moscada \\

Palo colorado ' '""'

Palo de hueso '_'_

Palo de matos ^

See footnotes at end ot table,

09603a 0—61 2

109

88

63

157

81

48

54

54

73

92

50

42

83

242

69

71

84

115

78

70

91

74

97

123

58

86

60

55

119

133

65

58

74

77

65

98

94

85

72

92

68

52

87

51

64

62

63

118

52

124

0. 39 0.40

. 42 .46

.70 . 74

.29 .30

. 59 . 61

. 82 . 89

. 68 . 74

. 64 . 68

. 66 . 68

. 57 . 59

. 77 .81

. 81 .89

. 45 . 46

. 23 .24

.65 . 69

. 67 . 72

.46 .48

. 51 . 58

. 61 . 64

. 59 . 62

. 54 . 57

. 62 .65

. 22 .23

. 51 .53

.73 .80

. 62 . 63

. 74 . 82

. 66 . 70

. 40 . 42

. 41 .43

.74 .78

. 55 . 57

. 47 . 50

.45 . 47

.45 .47

.59 . 62

. 29 .30

. 62 . 74

. 55 . 57

. 55 . 60

. 64 . 67

. 63 .68

. 63 . 67

. 80 . 86

. 70 . 75

.62 . 65

.59 .62

. 53

.81 .86

.50 . 53

0. 43

. 50

. 80

. 32

. 65

. 98

. 79

. 73

. 75

. 63

. 90

. 99

. 50

. 25

.75

. 78

.52

. 63

. 67

. 65

. 61

. 70

. 24

. 57

. 87

. 69

. 91

. 77

.45

. 45

. 84

. 61

. 53

. 50

. 50

. 65

. 31

.80

. 61

. 64

. 73

. 72

. 71

. 95

. 84

. 71

. 67

. 74

. 95

. 56
14 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 205

TABLE 5.—Speciftc gravity of green, air-dry, and ovendry wood—Continued

Species

(1)

Moisture

content of

green wood

(percent)

(2)

Specific gravity based on ovendry

weight and—

Green

volume

(3)

Air-dry

volume '

(4)

Ovendry

volume

(5)

Factor for

adjusting

specific

gravity ^

(6)

Panapén

Eoble bianco

Samán

Tabaiba

Tabonuco

Teca

Ucar

Yagrumo hembra

Yagrumo macho124

63

145

96

57

83

37

125

81

0. 27

.58

. 44

.38

. 53

. 55

. 93

.29

.36

0. 28

.60

.45

.39

.56

.56

.96

.30

.39

0. 30 0. 00180

. 64 . 00304

.48 .00298

. 41 . 00257

.59 .00299

.58 .00372

L06 .00336

.32 .00198

. 41 .00252

' Air-dry values are adjusted to 15 percent moisture

content using factors listed in column 6.

2 Factor represents the change in true specific gravity

for each 1 percent change in moisture content between 0

and 30 percent moisture content.

WEIGHT PER CUBIC FOOT

The weight of wood per cubic foot is useful in

determining the weiglit of finislied articles or in

estimating freight and handling costs. It is also

a common denominator used to compare the

density of one wood with that of another and it

often has more meaning to wood users than a

specific-gravity figure. However, the condition

of the wood, whether air-dry or green, or the

actual moisture content for which the weight per

cubic foot is quoted must be specified. This is

essential because the weight or specific gravity of

wood is influenced by the moisture content.

Furthermore, when the moisture content is below

the fiber saturation point, around 30 percent

^ Values are approximate because of occurrence of

severe distortion during seasoning of test specimens.

Values were computed from green to ovendry measurements and weights, assuming an equilibrium moisture

content of 30 percent.

moisture content, a further reduction in the

moisture content is accompanied by shrinkage and

a loss in volume.

The weights per cubic foot for air-dry wood at

15 percent moisture content and for green wood

at the moisture content specified as shown in table

6 are calculated from data in table 5. The weight

per cubic foot can also be determined for any

moisture content from 0 to 30 percent moisture

content by means of the factor in column 5 of table

6. Weight per cubic foot for wood at any

moisture content above 30 percent can be determined by multiplying the specific gravity in

column 5 of table 5 by 62.4 and then multiplying

this value by 1 plus the moisture content of the

wood expressed as a decimal.

TABLE 6.—Weight of green and air-dry wood

Green wood (at moisture

content listed)

Air-dry wood (15 percent

moisture conteTit)

Species

(1)

Moisture

content

(2)

Weight per

cubic foot

(3)

Weight per

cubic foot

(4)

Factor for

adjusting

weight per

cubic foot '

(5)

Achiotillo... ..

Percent

109

88

63

157

81

48

54

54

73

no

Pounds

51

49

71

47

66

76

66

61

71

Pounds

29

33

53

22

44

64

52

49

49

42

0. 1525

Aguacatillo._ _ _ __ . 1471

Algarrobo 1962

Almacigo . 1342

Almendra... . 2092

Ausubo 1424

Caimitillo 2002

Caimitillo verde 1918

Capá blanco 1729

Capá prieto 1805

See footnote at end ot table.
PUERTO RICAN WOODS

TABLE 6.—Weight of green and air-dry loood—Continued

15

Species

(1)

Green wood (at moisture

content listed)

Moisture

content

(2)

Weight per

cubic foot

(3)

Air-dry wood (15 percent

moisture content)

Weight per

cubic foot

(4)

Factor for

adjusting

weight per

cubic foot '

Caracolillo

Casuarina

Cedro hembra

Cieba

Cucubano

Cupey

Espino rubial

Eucalipto

Granadino

Guaba

Guajón

Guama

Guano

Guaraguao

Guayabota

Higüerillo

Jácana

Jagua

Jagüey blanco

Jobo

Jusillo

Laurel amarillo...

Laurel avispillo__.

Laurel geo

Laurel prieto

Laurel sabino

Mago

Mamey

Mango

María

Maricao

Masa

Moca

Motillo

Negra lora

Nemocá

Nuez moscada

Palo colorado

Palo de hueso

Palo de matos

Panapén

Roble blanco

Samán

Tabaiba

Tabonuco

Teca

Ucar

Yagrumo hembra

Yagrumo macho .

Percent

50

42

83

242

69

71

84

115

78

70

91

74

97

123

58

60

55

119

133

65

58

74

77

65

94

85

72

92

68

52

87

51

64

62

63

118

52

124

124

63

145

96

57

83

37

125

81

Pounds Pounds

72

72

51

50

69

72

53

69

68

62

64

67

27

71

72

72

74

64

55

60

76

54

51

50

46

72

35

71

59

66

67

60

74

75

72

62

60

71

77

70

38

59

68

46

52

62

79

41

40

58

64

34

17

50

52

35

42

46

44

41

46

17

38

57

47

59

51

30

31

56

41

36

34

34

44

21

54

41

43

48

48

47

61

54

47

44

2 59

61

37

20

42

32

28

40

40

69

22

28

' Factors for adjusting weight per cubic foot for each 1

percent change in moisture content between 0 and 30 percent moisture content.

2 Approximate values.
16 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 205

SHRINKAGE

The average shrinkage values (table 7) for the

Puerto Rican woods involved are considerably

below similar values for hardwoods of comparable

density from the United States. This accounts

in part for the generally satisfactory manner in

which most of the Puerto Rican woods can be

air-seasoned.

The ratio of tangential to radial shrinkage is an

indicator of the amount and severity of the warp

and surface checking that develops during seasoning. The so-called nonrefractory woods, such as

mahogany, have nearly equal radial and tangential values. Woods undergoing tangential shrinkage not more than two times the radial shrinkage

will generally season without excessive warping

or checking. But those with a ratio of 21^ or

more will usually season rather unsatisfactorily

unless given more than average care.

TABLE 7.—Shrinkage values, in percent of original green measurcTnents

Species

Green to air-dry '

Radial Tangential

Longitudinal

Volumetric

Green to ovendry

Radial TangentialLongitudinal

Achiotillo

AKuacatillo

Algarrobo

Almacigo

Almendra

Ausubo

Caimitillo

Caimitillo verde

Capá blanco

Capá prieto

Caracolillo

Casuarina

Cedro hembra

Ceiba

Cucubano

Cupey

Espino rubial

Eucalipto

Granadino

Guaba

Guajón

Guama

Guano

Guaraguao

Guayabota

Higüerillo

Jácana

Jagua

Jagüey blanco

Jobo

Jusillo

Laurel amarillo

Laurel avispillo

Laurel geo

Laurel prieto

Laurel sabino

Mago

Mango

Mamey

María \.V^\

Maricao

Masa

Moca

MotiUo ]^'"

Negra lora

See footnote at end of table.

0. 8

2. 5

1. 7

1. 1

1. 8

2.5

2. 6

2. 1

1. 2

LO

1. 8

2. 4

2. 1

. 8

2.0

2. 1

1. 5

3. 3

1. 1

1. 0

2.0

1. 6

1. 3

1. 4

2. 8

1. 6

3. 6

1. 7

1.0

.9

2. 2

1. 1

1. 4

1. 2

1. 3

1. 5

1. 4

.8

5. 4

3.0

1.5

2. 1

1. 2

2. 4

2. 4

7.5

3. 5

2. 1

2. 5

4. 7

2. 6

9. 7

2. 5

2.0

3. 7

5.8

3. 5

5. 4

4. 1

2. 8

1.9

3.9

2.0

3. 3

2. 4

3.0

2. 6

2. 4

2.3

12. 1

46

3.5

3. 4

2. 5

4. 5

4. 8

0. 04

.07

. 20

.28

. 11

. 10

. 21

. 13

.06

.04

. 04

.04

. 11

. 10

. 21

. 10

.08

. 15

. 06

.08

.07

. 11

,02

.06

. 21

.06

. 04

.06

,04

, 10

,08

, 12

,08

, 10

, 02

,05

, 18

38

,03

,07

18

,06

"07"

3.3

9.8

5. 4

3.4

3.0

4. 8

8. 1

5. 1

3. 8

6.0

6.8

4 2

12. 7

3. 8

3. 1

5. 6

4. 4

6. 1

5. 1

8. 4

5. 2

8. 9

2. 7

4. 1

3. 8

3.3

17.0

7.5

5.0

5.6

3.8

6.8

7.4

2. 9

4. 9

4 4

2.6

4. 5

6. 6

5.9

2. 1

5.0

4 7

4 2

6. 2

2.8

3.6

4 8

4. 0

3.0

3. 8

6.2

3.0

7. 9

4 6

2. 9

2. 7

4 8

3. 7

3. 9

3.4

3. 6

3.8

3.2

3.0

7.7

6.2

4 0

48

3.6

6.7

6.5

5. 7

11.3

8.3

4. 2

5. 7

10. 1

7. 8

7.8

7. 1

6. 4

11.

6.

5.

9.4

6. 3

13. 3

5. 7

6.0

7.7

6. 6

7.6

7. 7

11. 2

6.3

10.7

9. 1

6.4

4 7

8.0

6.0

6. 9

5. 8

6. 4

6. 2

5.2

6. 1

15.2

8.4

8.2

7.3

7. 1

10. 1

10.0

0.28

.36

. 54

. 71

.36

.34

. 41

. 31

. 23

.25

. 19

.29

.27

. 11

. 33

.49

.38

. 30

.30

.30

.39

.26

.47

. 13

.20

.36

.27

. 18

. 22

. 13

.29

. 21

.41

.27

. 22

. 13

.30

.59

.71

.30

.39

.25

.24

. 16

.27
PUERTO RICAN "WOODS

TABLE 7.—Shrinkage values^ in percent of original green measurements—Continued

17

Species

Green to air-drv '

Radial Tangential

Longitudinal

Volumetric

Green to ovendry

Radial Tangential

Longitudinal

Volumetric

Nemocá

Nuez moscada

Palo colorado ^

Palo de hueso

Palo de matos

Panapén

Roble blanco

Samán

Tabaiba

Tabonuco

Teca

Ucar

YagTumo hembra

yagrumo macho.

1. 8

1. 8

5. 1

2. 2

1. 1

1. O

1. 2

.7

.6

1. 4

.5

L3

{')

3. 1

3.4

3. 1

10. 3

3.5

3.0

2.7

L6

1. 2

1.8

2. 7

1. 1

2.3

5.6

0.08

.08

. 31

. 10

.01

. 13

. 18

. 16

.03

. 12

.02

.06

O

06

5. 2

5.0

14. 5

5.8

4. 1

3.8

3.0

2.0

2. 4

4.2

1.6

3.6

8.5

4.9

4.6

10. 1

6. 3

3.6

2.7

4. 1

2. 4

2. 4

4 1

2. 1

4 4

2.0

4 9

7. 4

7.0

20.6

8.7

7. 4

5.7

5.5

4 2

4 8

6. 4

3.8

7. 9

6.2

8.2

0.35

. 18

.62

.35

. 14

. 47

.28

.40

.07

. 24

.35

. 24

. 22

. 16

12. 3

11.4

29. 1

14 8

10. 9

8.7

9.7

6. 9

7. 1

10. 5

6.2

12. 2

8.3

12. 8

> At 15 percent moisture content.

2 Approximate values.

3 Reliable data not available for shrinkage percent from

green to air-dry.

Eelatively few of the Puerto Rican woods exhibited excessive directional or volumetric shrinkage. However, those that did, including

aguacatillo, algarrobo, casuarina, eucalipto,

mamey, and yagrumo hembra also developed excessive degrade during seasoning. Longitudinal

shrinkage was relatively high in several woods

having interlocked grain. This is a normal occurrence for woods with this type of grain and

is not necessarily accompanied by excessive degrade. Longitudinal shrinkage of more than 0.3

percent is usually indicative of excessive warp.

Palo colorado, with a longitudinal shrinkage of

0.62 percent, is a notable example. This wood,

having tightly interlocked grain, developed very

severe warp along with equally severe surface and

end checking.

Machining Characteristics

PROCEDURE

The machining procedures were designed to

test the different woods under a uniform and fairly

typical set of conditions prevailing in Puerto

Rico.^ The woodworking machines and accessories used in the tests were typical of the small

hobby-shop size equipment found in most woodworlfing shops on the island. Except for the

use of forms and jigs to assure uniform handling

of the test specimens, the methods and techniques

of machining were typical of those used in working Mexican mahogany in Puerto Rico.

The procedures were not selected as the most

suitable for the different woods but rather to show

what actually happens under the specified conditions. Thus the results show the comparative

' Tests were patterned, with changes as required to meet

local conditions, after procedures developed by E. M.

vTñi ^^ '^^^ ^"^^ forest Products Laboratory and published in Machining and Related Characteristics of

Southern Hardwoods, U.S. Dept. Agr. Tech. Bui. 824,

42 pp. 1942.

machining qualities of the woods under one set

of uniform conditions.

SELECTION OF TEST MATERIAL

Nominal flat-grain, air-dry lumber free of knots

and seasoning defects was used in all machining

tests. Fifty boards of each species, 7 inches or

more wide, were selected at random, planed to

2%2 inch thickness, and cut into machining specimens for the different tests (ñg. 6). Test specimens were essentially heartwood, but pieces

containing sapwood were not discarded nor were

specimens rejected having some cross grain,

irregular grain, or density lower or higher than

average.

GRADING

The smoothness of machined surfaces is the

most important factor in judging the machinability of different woods. Accordingly, in this study

the test samples were examined for machining defects after each operation and were graded on a
18 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

numerical scale based on smoothness of cut. A

o-rade of 5 was considered excellent^ 4 good., 3 /«?>,

2 foor^ 1 eery poor, and 0 reject. Both the frequency and severity of defects were considered.

Each wood was ñnally rated numerically ^ according to the weighted average grade of all specimens

in each test. The percent of specimens grading

good to exceJIent or fair to excellent is also shown

for most tests. This figure, which combines two

or more grades and is expressed in percent, is not

necessarily comparable to the numerical ratingbased on the weighted sum of the assigned grades.

The woods were also separated into five broad

groups under each machining test, based on the

calculated ratings and the experience of the operators making the tests. Separating the woods into

excellent, good, fair, poor, and very poor groups

under the respective niacliining tests necessitated

placing certain woods in the top of one group

though they were only very slightly inferior to

those in the bottom of the next higher group. This

condition and the necessity for introducing personal opinion in making the separation into

groups should be considered by the reader when

comparing tlie relative mach inability of the different woods.

PLANING

Planing is one of the most important operations in most woodworking plants in Puerto liico.

Woods that plane poorly are difhcult to use where

smooth surfaces are required. Consequently the

planing characteristics of the dift'erent woods is

of primary importance in determining their utility

for specific uses, especially in furniture manufacture. The tests were designed to measure and

compare the planing qualities of the difi'erent

woocls under uniform and fairly typical local

conditions.

Procedure

The machine used in the tests was a 4- by 12-inch

smgle-surface cabinet planer designed" for fine

work in small woodworking shops. "More than 90

percent of all planers used on the island are of

this type. The cutter head, holding three 12-inch

knives, revolved at 4,500 r.p.m., making 60 cuts

per inch. All tests were made with a knife angle

of 29° and at a feed rate of iTi/o feet per minute.

The 29° cutting angle is somewhat greater than

the 20° to 25° generally recommended for hardwoods, but it is typical foi' the type of machines

used m Puerto Pvico. The knives were kept sharp

at all times by frequent light sharpening and

'Calculated by totaling the luimerical gnules nf all samples and multiplying this sum by 0.4 when .10 samples were

used, 0.2 for 100 samples, and 0.1.3.33 for 1.50 samples

occasional grinding and jointing in a machine

specially designed for that purpose.

Test specimens were essentially clear, flat-grain

material, 4 inches wide, 3 feet long, and 25/32

inch thick. All material was air-dry. The tests

involved ])laning 50 specimens of each wood at %2»

i/ie, and % inch depth of cut, totaling 150 different

tests for each species. Grading was based on the

frequency and severity of defects occurring during the planing; namely, chipped grain, raised

grain, fuzzy grain, and chip marks fiig. 7). The

number and severity of chip marks was fairly

constant at each depth of cut for the different

woods, so this test was eliminated from the final

analysis. The final grade of each specimen was

based on the lowest rating for any type of defect

]n'esent, because defect determines the amount of

sanding required to make the piece acceptable for

commercial use.

Results

Nearly two-thirds of all the woods rated good to

excellent in planing. This was based on a weighted

average of all specimens planed to three depths of

cut (table 8). Of the 60 woods tested, only 6 were

considered poor to very poor in planing properties,

and 16 rated fair. Slightly more than one-half

of the woods planed better than Honduras

mahogany.

Specific gravity and texture appear to have little

eri'ect on planing qualities. Woods having uniformly straight grain generally plant better than

those Avith irregular grain, although certain woods

with heavily interlocked grain, such as palo colorado, planed very well. Chip marks were few in

all woods at 1^2 iiif'h depth of cut, moderate at Vie

inch, and frequent to severe at Vs inch. However,

an efficient exhaust system would have eliminated

nearly all of this defect.

The proportion of pieces rating good to excellent at different depths of cut varied according to

species, but, in general, better surfaces were obtained at %- and yig-inch cuts than at 1/30 inch.

Table 9 shows that the heaviest cut, % inch, frequently gave the best results.

This is contrary to the results obtained with

larger cabinet i:)laners. The difference is due to

the vibrations that occur when very thin cuts are

made in a small single-surface planer of the type

used in these tests. Inasmuch as the test was designed to compare and rate the different woods

under uniform and fairly typical conditions, most

of those exhibiting fair "to very poor planing

qualities miglit be improved if better equipment

and techniques were used.
PUERTO RI'CAN WOODS 19

Â

B

tsx'%

Ï

c

\ff.

%

. ! S"

D

\

é * »

A

B

F-^95314-315

FIGURE 6.—For each species, a set of sample pieces was prepared for the machining tests. Left, Before machining ;

right, after machining. A, Planing and screw splitting; B, turning: C. sanding; and D, shaping, mortising, and

boring.
on U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

TABLE 8.—Flaniiui : comparative riding of all speciefi, based on average^i for three depths of cut ^

Species Rating 2 Species Rating - Species Rating

EXCELLENT

Poihti 96

93

93

93

91

90

90

90

89

89

89

88

88

87

87

86

85

85

84

84

83

GOOD—Continued

Guayabota

Yagrumo macho

Cucubano

83

82

82

82

82

82

81

80

79

78

77

76

76

74

72

72

72

70

69

68

68

67

FAIR—Continued

Mango 66

Tflhaiba Roble blanco

Masa_

68

65

Guano Nemocá

María

Espino rubial

Nuez moscada

Laurel sabino

65

Laurel geo

Almacigo

65

Aguacatillo 63

Palo de matos

Eucalipto

Samán

63

63

Capá blanco 63

GOOD

Capá prieto

Laurel prieto

Laurel avispillo

Granadino

Tabonuco

Negra lora

Panapén

POOR

.lusillo

Higüerillo

Laurel amarillo

Mago

Palo de hueso

VERY POOR

Almendra

63

62

Caimitillo verde Guaba

Caoba hondurena ^

Guajón

Guama

FAIR

Cupey

Algarrobo

Jácana

Casuarina

Ucar

61

60

Teca

Cedro hembra

Ausubo

Achiotillo

59

57

57

Maricao

Yagrumo hembra _ Motillo

Caimitillo

52

I lí.'%, J-íe, 1,< and y%2 inch depth of cut.

2 Calculated by totaling the numerical grades of the 150 samples of each wood and multiplying this sum by the

factor 0.1333 (100 divided by the possible total if all pieces were blemish-free. 150X5 =750).

TABLE 9.—Plardng: percentage of aaniplex rated good to excellent at different depths of cut^

Species

Achiotillo

Aguacatillo

.Algarrobo

Almacigo

Almendra '

.Ausubo

Caimitillo (mesa).

Caimitillo verde--

Caoba hondurena

Capá blanco

Capá prieto

Caracolillo

Casuarina

Cedro hembra

Ceiba

Cucubano

Cupey

Espino rubial

Eucalipto

Granadino

Guaba

Guajón

Guama

Guano

Guaraguao

Guayabota

Higüerillo

.lácaiia

.lagua

.Jagüey bin neo

Depth of cut

inch

94

100

50

80

6

74

86

64

20

100

92

36

100

100

64

38

32

66

58

48

56

52

82

92

90

8

54

78

92

86

96

30

88

O

74

82

90

34

15

96

36

100

100

74

52

28

82

70

44

42

48

96

82

70

8

36

92

92

36

54

4

80

74

86

44

25

92

74

91

100

80

46

14

72

48

60

42

36

94

90

62

4

16

96

92

Species

Jobo

Jusillo

Laurel amarillo _

Laurel avispillo.

Laurel geo

Laurel prieto

Laurel sabino.

Mago

Mango

Mamey

Mariât

Maricao

Masa

Moca

Motillo

Negra lora

Nemocá

Nuez moscada.

Depth of cut

Yt, inch

Palo colorado.

Palo de huesoPalo de matos.

Panapén

Roble blanco..

Samán

Tabaiba

Tabonuco

Teca

Ucar

Yagrumo hembra.

Yagrumo macho..

100

6

24

74

88

62

20

4

32

88

16

92

20

90

78

34

42

34

96

4

78

24

34

68

98

56

96

31

70

86

inch

82

14

8

66

72

80

22

2

32

96

20

86

30

90

74

6

26

14

96

6

76

20

24

80

94

46

82

36

80

84

82

12

8

64

70

54

20

6

32

88

28

62

34

9J

64

18

14

24

4

62

26

36

64

90

46

90

28

86

58

' Considering all defects except chip marks.
PUERTO RICAN WOODS 21

SI-24571-569-F

FIGURE 7.—Planning defects : A. Torn grain : B, chip marks ; C. raised grain ; D, fuzzy grain.
22 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 0.5

SHAPING

Shaping is a common operation in woodworkiiio- plants, particularly those that manufacture

furniture and related items. The operation generally involves cutting a pattern on the edge of exposed stu'faces such as tabletops and shelving.

Its primary function is to add to the attractiveness

of the finished products. Consequently, the

smoothness and detail of the shaping is of primary

importance and was used as a basis for grading

the tests specimens.

Procedure

The machine selected for the tests -was a singlespincUe type, operated at 11,000 r.p.m. by a beltdriven 11/2-horsepower electric motor, and fed by

hand. Small machines of this type are used in

most furniture plants in Puerto Rico. A 2%-inch

cutter head holding three steel knives was used

throughout the tests. The knives were of a common commercial pattern, cutting an outline varying from right angles to parallel to the grain.

Knives were sharpened at frequent intervals and

were replaced when any appreciable wear was

evident.

Test specimens of each species consisted of 50

pieces of typical flat-grain material, 4 hj 18 inches

in dimension and -%2 inch thick. Specimens were

first handsawed to a curved outline on one side

and one end and then fastened to jigs and handfed

in two operations past the cutters. One operation

involved shaping along the end at right angle to

the grain and the other followed the curved outline previously cut on each sample (fig. 8).

After shaping, the samples were graded on the

basis of four types of defects : torn grain, chipped

grain, raised grain, and fuzziness. For all practical purposes, the most defective place on a shaping determines its grade, as the defect at that

point controls the amount of sanding required

to make the piece acceptable for commercial use

(fig. 9).

Results

More than two-thirds of the woods rated good

to excellent in shaping, and only 10 were considered poor or very poor. The most unsatisfactory woods were in all cases light to extremely

light in weight, whereas the medium to very heavy

woods generally gave the best results.

FioiTRE s..-riuÍNi,oJ sliciping held in the jig used in the test.

F-495316
PUERTO RI'CAN WOODS 23

TABLE 10.—Shaping: comparative rating of all . ^pecien huxed on smoothne><s of r-ut vhen considenng

all side and end defects

Species Rating

EXCELLENT

Ausubo

Guayabota

Caimitillo

Caimitillo verde

Motillo

Mamey

Roble blanco

Jagua

GOOD

Caoba hondurena

Jácana

Caracolillo

Nemocá

Negra lora

Palo de matos

Ucar

Cucubano

Palo colorado

Casuarina

Masa

Jusillo

Yagrumo macho

Nuez moscada

Granadino

Algarrobo

Laurel prieto

Cedro hembra

Guaraguao

Eucalipto

Laurel avispillo

Capá prieto

Cupey

María

Laurel amarillo

99

97

96

96

95

94

94

92

91

91

90

89

89

86

86

85

85

84

83

83

82

82

81

80

80

80

80

80

80

80

Good to

excellent

shaping

Percent

100

96

98

96

96

100

98

96

90

86

86

76

92

92

92

88

84

78

76

76

86

90

78

82

92

96

90

76

76

70

Species

GOOD—Continued

Maricao

Capá blanco

Laurel sabino

Guajón

Teca

Tabonuco

Higüerillo

Laurel geo

FAIR

Mango

Palo de hueso

Tabaiba

Moca

Samán

Almendra

Yagrumo hembra

Guama

Espino rubial

POOR

Jagüey blanco

Cieba

Guano

Guaba

Achiotillo

Aguacatillo

Jobo

VERY POOR

Almacigo

Panapén

Mago

Rating

79

78

78

77

76

75

75

74

72

70

68

68

66

65

62

61

60

59

58

58

56

54

52

52

46

33

24

Good to

excellent

shaping

Percent

72

88

76

64

74

76

64

60

56

54

48

42

40

46

38

8

24

22

28

22

6

10

14

8

0

4

0

Shaping chitracterietics were not always related

to specific gravity, for some of the heaviest woods,

such as higüerillo and casuarina, rated well down

the list. On the other hand, ausubo, a very heavy

wood, produced the best shapings of all, while

Honduras mahogany was ninth in the list of 60

woods studied (table 10).

Inasmuch as this test compared the shaping

((ualities of the different woods under typical and

reasonably uniform conditions, those exhibiting

fair to poor shaping qualities might have been

improved if special machining techniques were

employed to overcome their specific problems.

TURNING

Wood turning in Puerto Rico is generally

limited to bed posts and a few similar items in

the manufacturing of furniture. Imported Honduras mahogany is customarily used. Of the

local woods, tabonuco is usually selected for this

work, although numerous other species have equal

or superior turning qualities. Most shops use

small, handfed, hobby-shop size machines, but a

few semiautomatic machines are coming into use.

Procedure

The tests were made with a small hand lathe

embodying the back-lathe principle with certain

ntodifications. The knife was a special milled-topattern type suitable for turning small pieces with

(•onsideral)]e detail. It was held in a compoimd

rest of the type used for metal turning. Test

material consisted of 50 pieces of each wood, ~%2

inch square and 5 inches long. The test involved

most of the common cuts in turning, including

turning a bead, cove, and fillet, plus cuts at several

different angles to the grain on each test specimen.

All turning was done at 3,300 r.p.m.

Turnings were graded on the basis of smoothness of cut and sharjjness of detail, with the poorest i)oint determining the grade for the specimen.
24 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

F-495317

FIGURE 9.—Test samples showing different degrees of defect when shaped at right angles to the grain.

The governing factor \Yas the amount of sanding

required to bring each specimen to an acceptable

standard. Grading was done on a basis of 0 to .5

(fig. 10), as described on page 17.

Results

Tlu-ee-quarters of the woods rated fair to excellent when turned under what is considered

severe turning conditions (table 11). In general,

tlie heavier woods turned better tluiii those of low

density.

M-109O37

Ficiüic 10,—Defects and different degrees of defects that

ilevelDp during turning.

All of the woods that rated very poor are very

light in weight. However, only part of the woods

rated excellent are extremely heavy. For example,

moca is moderately heavy, yet it is an excellent

wood to turn. Twelve species turned better than

caoba liondureña, which is well liked in the turning trade. Tabonuco, the favorite turning wood

in Puerto Rico, and cedro hembra, another wellregarded wood for turning, rated only fair on the

basis of these tests. Surprisingly, ausubo, one of

the heavier woods, turned poorly under the test

conditions. Inasmuch as the tests were conducted

to determine the comparative turning qualities of

the woods, it is evident most of them might give

better results with more careful handling.

BORING

Boring is a common operation in woodworking

plants that make furniture and other wood products in which dowels, rungs, spindles, or screws

are used in the assembly process. Machines used

in boring vary in size from small single-spindle

drill presses to modern multiple-spindle boring

machines capable of boring a dozen or more holes

simultaneously. Many difi'erent types of wood

drills and bits are available for the varied and

often highly specialized boring operations. Although boring work is generally concealed in the

finished product, the smoothness of cut and acctiracy of hole size are of primary importance

when dowels or rungs are used. A clean, smooth

cut with a minimum tearing of the grain pro^^des

a tight fit and good glue-holding surfaces. Accurately sized holes are also important for obtaining a tight fit and a strong, thin glue bond between the hole surfaces and the dowel or rung.

Procedure

A single-spindle, motor-driven boring machine

operating at 1,725 r.p.m. was used in the tests.

The bit was a 1-inch, spear point, single twist,

solid center type. It was maintained in good cutting condition by frequent sharpening, and it was

replaced at the first sign of wear or damage. Test

specimens were lield securely during boring in a

special jig, and the bit was fed into the wood at a

uniform rate by a hand-feed mechanism (fig. 11).

Mechanical means of feeding the bit into the wood

would liave been desirable but were not available.

Two holes were bored in each 50 test specimens

of each species, 2%2 inch thick. The 100 holes for

each wood Avere then graded for smoothness of

cut, and they were rated according to the numerical system described on page 17 (fig. 12).

The accuracy of hole size was measured foi'

several species and was found to be at least as

uniform as the size of the bits and doweling available on the local market. Because of tlie difficulty of nuiking accurate measurements of hole

size, this part of the test was abandoned.
PUERTO RICAN WOODS 25

TABLE 11.—Turning : rompar(ifive rating of all .species. ha-Hed on i<moothness of cut

(Based on percent of turnings graded fair to excellent)

Species Rating Species Rating Species Rating

EXCELLENT

Guavabota . . 100

100

98

98

96

96

96

96

94

92

90

90

90

90

86

86

84

84

82

82

80

GOOD—Continued

Palo de heuso .. 80

76

76

76

72

72

70

68

68

64

60

60

58

.'-8

50

50

50

48

48

46

44

FAIR—Continued

Tabaiba . - 40

Teca Eucalipto

Jácana

Yagrumo hembra

Palo de matos

POOR

40

Jagua 38

Hiffüerillo . . . Negra lora

Ucar. Guaba

Cucubano

Moca

Guaraguao

Laurel sabino

Cupey

Nemocá

30

Algarrobo

Capá blanco

Capá prieto

GOOD

28

Jobo

Mariá - . - -

28

Laurel amarillo

Caimitillo

Laurel geo

Nuez moscada

28

Espino rubial

Jagüey blanco

\ffiiacatillo

24

24

18

Granadino Roble blanco __. 14

Caimitillo verde.. . .

FAIR

Cedro hembra

Laurel avispillo

Tabonuco

Casuarina .___...

Achiotillo 10

Caoba hondurena

Masa - VERY POOR

Ceiba

Yagrumo macho

Caracolillo

Palo colorado

Motillo

Mamey

Jusillo

6

2

0

Guajón _ ... Guano 0

Guama . .- Mango Maso - - 0

Maricao Laurel prieto Panapén 0

Results

The majority of these woods bored satisfactorily. Only 4 of the 60 woods exhibited very

poor qualities in this respect, and 11 rated poor.

Specific gravity appeared to be an important

factor, with the heavier woods producing considerably better holes than light to medium density

woods. All woods rated very poor and most of

those rated poor were among the lightest used in

the tests.

The test was designed to treat all woods alike

in order to develop comparative ratings for the

different species. Consequently, most of the

woods exhibiting unsatisfactory boring qualities

could be handled more satisfactorily under different and less severe conditions. Even woods like

guano and panapén, although very difficult to

bore, can be bored satisfactorily if special techniques and the proper bits are used.

A limited number of measurements of hole size

indicated that hole size was most accurate in the

woods rated good and poorest in those producing

rough, torn holes. Holes were generally undersize m the dense, good-boring wood^-actually

smaller than the bit. Holes were considerably

oversize m the woods with rough, torn borings.

Lharrmg is a difficulty frequently encountered in

boring very dense wood, but this can be eliminated

by increasing the rate of feed

MORTISING

Mortise-and-tenon joints have been used for

centuries in fabricating all types of wooden stractures, furniture, and other objects. The mortise,

usually a rectangular hole made to receive the

tenon of another member, was for many years cut

by hand. When nails, screws, and other fastening

devices became plentiful and cheap, this type of

joineiy was no longer uecessar}^ Such joints are

still used, but now most mortises are cut by machines, principally in furniture and millwork

F-495318

FiGUEE 11.—Blank held in jig ready for boring test.
26 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

TABLE 12.—Boring: com-parative rafAng of all

species hased on nmoothnessi of cut

r-405310

FIGURE 12.—Boring test .sample.s, showing the variation

in smoothness of ent.

plants. Since tenoning is done in operations similar to shaping and planing, separate tests of

tenoning were not made in this study.

The mortising tests were made with a hollowchisel mortising tool operating in a conventional

drill press. This type of mortising tool consists

of a specially designed bit revolving within a hollow square chisel. It cuts a square hole. As the

tool is pressed into the wood, the bit bores a round

hole, and the hollow chisel, following close behind

the bit, cuts out the corners.

Procedure

Fifty specimens of each wood, 25,/^ inch thick,

were usecl for the test. One mortise was cut in

each test sample with a standard i/2-ii^cb mortising

tool, the bit revolving at 1,250 r.p.m. Test specimens were held snugly in place during mortising

by means of a special jig. Because the machine

used was of the hand-fed type, considerable care

was taken to maintain a uniform rate of feed for

all species. Both the bit and chisel were

sharpened at frequent intervals and replaced

whenever any wear or damage was evident.

The linished mortises (figs. 13 and 14) were

graded for smoothness of cut in accordance with

the numerical grading system described on page 17.

An attempt to measure the accuracy of mortise

size with a steel gage was impractical, because the

variation in size of mortising tools and the inaccuracy of measurements appeared to be greater

than the variation in mortise dimensions of different Avoods.

Results

Most of the Puerto Rican woods mortised

satisfactorily. Ten of them mortised better than

caoba hondurena and all but 15 gave good to excellent results. Specific gravity appears to be an

nnportant factor, with the heavier woods generally

producing better mortises than the light-weight

softwoods. In general, cuts parallel to the grain

were acceptably smooth in most woods. How6ver, cuts across the grain varied widely, some

of them showing considerable crushing and tearing. The comparative i^ating of the v-oods as

listed ni table V.>> is based largely on smootluioss

ot cut across the grain.

Good to

Species Rating excellent

holes

EXCELLENT Perl'eut

Ausubo . _ - 100

100

100

Ucar 100

Maricao . _ 100 100

Capá bianco - 100 100

Motillo - 100 100

Guavabota _ ___ 100 100

Caracolillo 100 100

Palo de hueso 100

99

99

100

Roble h)lanco 100

.Jácana 100

.Tagua - 96 100

Laurel amarillo 95 100

Caimitillo _ __- 95 99

Capá prieto - 95 98

GOOD

Masa - 94 100

Nemocá_ 94 97

Guama 93 100

Granadino 92 98

Moca - 92 98

Caimitillo verde - 91 97

Palo colorado 91

91

94

Algarrobo ._ 90

.Jusillo - - - 90 100

Negra lora - 89 96

Mamey - 87 95

Teca - 86 85

Higüerillo ^ - 85 98

Casuarina 84 90

Laurel sabino _ - 84 79

Laurel avispillo - 83 92

Nuez moscada 82 89

Guaba ^ . _ - 82 79

Mango 81 80

Caoba hondurena. 81 76

FAIR

Palo de matos 80

79

79

Cucubano 82

Samán 77 76

Guaraguao - 76 66

Eucalipto - 75 73

Cupey - 75 68

Tabonuco 74

73

54

Espino rubial _ . 62

Almendra 73 54

Laurel prieto - 71 51

Laurel geo - 70 46

POOR

Cedro hembra 68

67

44

Yagrumo macho 42

María 67 37

Tabaiba 63 16

Jagüey blanco 62 16

Guajón 60 19

Jobo _ 59 11

Ceiba 59 26

Almacigo 53 7

Aguacatillo 53 9

Achiotillo- - . 51 2

VERY POOR

Guano _ 48

45

11

Yagrumo hembra 2

Mago 42 0

Panapén _ . ' , 30 7
PUERTO RICAN WOODS 27

F—195320

FIGURE 13.—Test samples held in jig for mortising test

with hollow mortising chisel.

FIGURE 14.—Test samples cross-sectioned to show different

degrees of tearing that occurred in mortising.

TABLE 13.—Mortising : comparative rating of all species, based on, smoothness of cut

Species

EXCELLENT

Capá blanco

Jagua

Nuez moscada

Roble blanco

Uear

Ausubo

Maricao

Masa

Palo de hueso

Xemocá

GOOD

Caoba hondurena

Laurel amarillo

Caracolillo

Caimitillo verde

Motillo

Caimitillo

Algarrobo

Cucubano

Guayabota

Guaba

Laurel avispillo

Palo colorado

Negra lora

Guama

Jácana

Moca

Eucalipto

Capá prieto

Jusillo

Teca

Guaraguao

Cedro hembra

Granadino

Rating

100

100

100

99

99

98

97

96

95

95

94

93

93

93

93

92

92

92

91

90

90

90

90

90

89

89

89

86

85

85

Good to

excellent

mortises

Percent

100

100

100

100

100

100

100

100

100

100

96

100

100

100

98

100

98

98

100

100

100

98

98

96

100

98

94

98

96

86

94

100

98

Species

GOOD—Continued

Laurel sabino

Mango

Tabonuco

Cupe}'

Yagrumo macho

Casuarina

Samán

Higüerillo

Mamey

María

Laurel prieto

Laurel geo

FAIR

Palo de matos

Ceiba

Guajón

Almendra

Espino rubial

POOR

Tabaiba

Achiotülo

Jagüey blanco

Yagrumo hembra

Jobo

Aguacatillo

VERY POOR

Guano

Almacigo

Panapén

Mago

Rating

85

84

84

84

84

83

82

82

82

81

81

81

80

80

80

77

73

67

66

65

62

62

58

48

46

44

42

Good to

excellent

mortises

Percent

94

96

86

86

82

100

90

90

86

94

90

82

82

72

78

56

36

34

28

24

16

18

12

0

14

0
28 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

SANDING

Sanding is an important operation in preparing

many products for paint, varnish, or otlier finishes; it removes phming defects such as chip

marks, torn or raised grain, knife mai-ks, fuzz, and

small scratches or dents. Some coarse or openo-rain ^voods also require considerable sanding to

provide a smooth surface for finishing. The

higher grade products, such as furniture and

cabinetwork, are carefully sanded before finishing.

Blemishes that are not removed in the sanding are

often magnified when clear or partially opaque

finishes are applied. Consequently, woods selected

for high-quality products must possess reasonably

good sanding characteristics.

Procedure

The tests were made with a small power-driven

belt Sander using fi-inch-wide endless sanding belts

approximately 14 feet long. Fifty 2- by 10-inch

test specimens of each wood were sanded with 1/0

grit, 50 with 2/0 grit, and 50 with 3/0 grit. Garnet abrasives were used in all tests. The abrasive

paper was replaced frequently to avoid the efí'ects

of wear, which reduces the size of the grit. Sanding was done parallel to the grain in a special jig

holding eight test specimens at one time. Pressurée of the sanding belt against the test specirnens

was applied by hand as uniformly as possible.

Duration of the sanding varied according to the

size of the grit; the finest grit required the most

time. A watch was used to keep sanding time

constant for each size of abrasive paper. After

sanding, the samples were inspected visually for

both fuzz and scratches, and they were graded on

degree of freedom from these defects.

Results

The woods exhibited generally satisfactory

sanding properties, with caoba hondurena at the

top of the list and teca at the bottom (table 14).

Thirty-eight of the 60 woods tested rated good to

excellent, and only 11 were in the ¡DOor to very

poor class. Specific gravity did not appear to be

a dominant factor in sanding properties, although

lightweight, open-textured woods tended to fuzz

up more than others. Scratches were more readily

visible on the surface of dense, fine-textured

woods, just as fine scratches stand out on a mirror

or polished metal surface. In general, finegrained wood required a finer abrasive than

coarse-grained Avood. The tests indicated that 3/0

grit abrasive is normally required to reduce

scratching and fuzzing to an acceptable minimum

for high-quality finishes.

TAIU.E 14.—Si/ní/Í7i(/: comparatirp rating of all specie-'^, based on percentage of scratch- ami'

fuzz-free piecei< ^

Species Rating Species Rating Species Rating

EXCELLENT

Caoba hondurena

Nuez moscada

91

90

83

79

fi 8

(i 7

66

60

.53

.51

49

45

45

43

43

41

41

40

39

35

35

GOOD—Continued

Jagüey blanco

Casuarina

34

33

32

32

32

31

30

29

29

28

27

26

25

23

23

23

23

22

20

20

20

FAIR—Continued

Jobo

Palo colorado

Higüerillo

Laurel prieto

Caimitillo

19

18

17

Moca Masa

Maricao

Yagrumo hembra

Almendra

17

Ceiba 14

Ausubo

Guama

Laurel geo

Cucubano

POOR

Guayabota

Espino rubial

Mango

Jusillo

Mamey

13

11

Guaraguao

Roble blanco., _ _._

Capá prieto

María

GOOD

Guaba

Negra lora

Capá blanco

Eucalipto

Ucar

Caimitillo verde

Caracolillo

(i

.Jácana 5

.5

5

Yagrumo macho

Motillo

Granadino.. Cupe_v

.Jagua

Panapén

Maeo

]

Algarrobo . 1

Samán Laurel amarillo

VERY POOR

Achiotillo

Almacigo

Nemocá ...

FAIR

Guano

Cedro hembra 0

Aguacatillo Tabaiba

Lavu'el avispillo

0

Palo de matos Palo de hueso 0

Tat^onuco Teca 0

' Weighted average for 1/0, 2/0, and 3/0 grit sanding belts.
PUERTO RICAN WOODS 29

Related Properties

SCREW SPLITTING

In Puerto Rico, screws are usually driven with

handtools. CVjnsefiuently, handtools were adopted

for these tests of Puei'to Rican woods. Screws

have the greatest holding power when driven

snugly into prebored lead holes that are equal to

the core diameter of the screw at a point lialf

way down from the top of the threads. Normally screws are located as far from wood edges

as possible. However, since the object here was

to evaluate screw-splitting tendencies of the different species, considerably more severe test conditions were employed.

Procedure

Test material consisted of 25 boards % inch

thick, 4 inches wide, and 3 feet long. Four lead

holes, i/ie inch in diameter, were bored in a line

y^ inch from one end of each board and approximately % inch apart and from each edge. They

were about one-half the proper size for the No. 8

screws used in the tests. The lead holes were bored

with a hand-operated drill press to insure straightness. Four screws were driven through the lead

holes in each board into a softwood backing, using

a hand brace and screwdriver bit. Screws were

driven to a uniform depth, the base of the head

being flush with the top of the board (fig. 15).

After the screws were driven, the boards were

inspected for complete splits at the points where

the screws were sunk. A complete split was considered to be one that extended through the end

of the board and back beyond the screw. It also

had to be visible on both sides of the board. The

woods were then rated according to their comparative resistance to splitting under the test conditions (table 15).

Results

The tests indicated that woods having uniformly straight grain are more susceptible to splitting than those having cross (interlocked) grain.

Lightweight woods also were less susceptible to

splitting than heavy, dense woods. All Puerto

Rican woods rated excellent in resistance to screw

splitting were either light in weight or possessed

# «L' m cF^ f

• # «^

m

FiGUBE 1.5.—Test samples illustrating screw splitting. Left, 0 ; center, 2 ; right, 3.

59603,3 0—«1 3
gQ U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

TABLE 15.—Screw splitting : comparative rating of all species, based on percentage of split-free pieces ^

Species Rating Species Rating Species Rating

EXCELLENT

Oiiano 100

100

100

100

99

97

96

91

89

89

86

83

81

79

75

69

68

65

63

62

60

GOOD—Continued

Laurel geo 57

55

53

53

51

51

49

46

46

44

43

43

40

40

38

37

36

35

34

34

32

32

FAIR

Masa

Caimitillo

Ausübe

Palo de hueso

Jácana

Negra lora

Roble blanco

24

23

Ceiba Espino rubial 22

AlTTiiiriffO Tabonuco 22

Pnlo colorado Almendra 2''

Nuez moscada 21

Mamev Palo de matos 20

Yagrumo macho

Aguacatillo

Cupev

POOR

Jusillo

Caimitillo verde

Achiotillo Laurel sabino 19

Panapén Laurel amarillo

Moca

Algarrobo

Guaba

Cucubano 18

Jagüey blanco Higüerillo 17

Yagrumo hembra

Eucalipto

Motillo 14

Capá prieto 14

Nemocá

Guama..

Jagua

Granadino

Teca

María

Oapá blanco

Guaraguao

Casuarina

Maricao 14

GOOD

Jobo

Mango

VERY POOR

Caracolillo

Ucar

Guayabota

8

Caoba hondurena

Guajón

Samán

Tabaiba

Laurel avispillo

8

5

' Cedro hembra not included fer lack of suitable material.

interlocked grain. Conversely, most of the woods

rated low were dense and characterized by straight

grain.

Because these tests were designed to produce

comparative results, the lead holes were purposely

made too small and screws were driven close

enough to the ends and edges of boards to obtain

a sufficient amount of splitting for comparative

purposes. Using larger lead holes and spacing

screws farther from the ends of boards would

reduce splitting in most of these woods, but this

would not change their inherent susceptibility to

splitting.

RESISTANCE TO DRY-WOOD

TERMITES

The West Indian dry-wood termite, or "polilla,"

Cryptotermes Irevis Walker, is possibly the most

destructive wood-boring insect in Puerto Rico.

With few exceptions, it can destroy any native or

imported woods. The winged adults move about

with ease, infesting wood wherever they find it—

the woodwork or framing in a house, the picture

frames on the wall, or the oxcart in the field. The

frequency and extent of damage by this termite

often is sporadic and unpredictable. Woods rated

very susceptible to attack often give long and satisfactory service. Yet at other times the same woods

are attacked'and almost completely destroyed

withm a few years, or sometimes in a few montlis

Despite this inconsistency, the wood listr sliould

recognize the relative susceptibilities of the different woods to damage and ultimate destruction

by this voracious enemy. He can then either use

woods having natural resistance to termites in

especially vulnerable locations or protect the susceptible woods with chemicals prior to use.

Procedure

Tests to determine the resistance of the different

woods to damage by the dry-wood termite were

conducted by Dr. G. N. Wolcott of the University

of Puerto Rico Agricultural Experiment Station,

using small test specimens prepared as part of this

study. Only heartwood was used in the tests, because sapwood is always less resistant and in most

cases very susceptible to termite attack. The specimens were placed in petri dishes with a small number of termites at room temperature and without

light. Relative I'esistance was established by progressive removal of the blocks attacked. The basic

numerical ratings were West Indies mahogany, 80 ;

capá prieto, 60 ; and laurel sabino, 40.

Results

Only 2 of the 60 species tested were rated very

resistant to attack by the dry-wood termites ; one

of these, teca, is an exotic tree grown only in plantations in Puerto Rico (table 16). Six species

were rated resistant, 13 moderately resistant, and

the remaining 39 very susceptible. On this basis,
PUERTO RICAN WOODS

TABLE 16.—Natural reniMance of irood.f to attacl: hy the We.<it Indian dry-^oood termite

31

Species

VERY RESISTANT

Algarrobo

Teca

RESISTANT

Ucar

Caracolillo

Guaraguao

Granadino

Cedro hembra

Capá prieto

MODERATELY

RESISTANT

Caoba hondurena

Ausubo

Samán

Motillo

Capá blanco

Caimitillo

Laurel geo

Mango

Jácana

Ratina

80

75

71

70

69

61

60

59

58

57

53

51

48

48

48

46

Species

MODERATELY RESISTANT—Continued

Moca

Masa

Higüerillo

Laurel sabino

VERY SUSCEPTIBLE

Maricao

Panapén

Aguacatillo

Caimitillo verde

Casuarina

María

Nuez moscada

Palo colorado

Palo de hueso

Jusillo

Palo de matos

Jagua

Roble blanco

Guano

Guayabota

Almendra

Rating

46-52

45

42

40

39

39

38

37

37

37

36

36

35

35

35

34

34

33

33

32

Species

VERY SUSCEPTIBLE—

Continued

Tabonuco

Eucalipto

Mamey

Cucubano

Guajón

Laurel avispillo

Guarna

Nemocá

Yagrumo hembra

Cupey

Espino rubial

Guaba

Laurel amarillo

Laurel prieto

Negra lora

Yagrumo macho

Jagüey blanco

Mago

Ceiba

Tabaiba

Jobo

Almacigo

Achiotillo

Rating

31

30

30

29

29

29

28

28

28

27

27

26

26

25

24

24

23

21

1 Tests conducted and ratings established by Dr. G. N. Wolcott, University of Puerto Rico Agricultural Experiment Station.

about two-thirds of the native species reaching

saw-log size are used at considerable risk of termite attack. JSTevertheless, this is not so serious as

it first seems ; woods like African mahogany, Philippine mahogany, and baboen—rated 30, 33, and

31 respectively in natural resistance to termites—

are used extensively on the island without serious

losses.^ Similarly, furniture made of maple and

birch from the United States has given excellent

service although rated very susceptible to termite

attack.

In many instances, furniture made of susceptible

woods becomes obsolete or worn out before being

seriously damaged by termites. Even the most

susceptible woods can be made more or less immune to termite attack if impregnated with one of

the numerous chemicals recommended for this

purpose.

Summary and Conclusions

All woods possess a number of properties that

affect their utility for diiïerent purposes, and this

should be considered in selecting material for any

specific purpose or product. Other properties

that are of only occasional significance are usually

ignored except in circumstances when they have

an effect on the usefulness of the wood. This study

has been limited to certain properties that are of

primary importance in the wood-using industry.

The summation of these properties provides a

fairly reliable estimate of the general utility of

each wood and its suitability for specific purposes.

The tests also show how each wood compares in

different qualities with other woods, its good qualities, and the difficulties that may be encountered

in its utilization for certain purposes.

' Wolcott, George N. An index of the termite-resistance

of woods. Univ. Puerto Rico Agr. Sta. Bui. 85, 26 pp. 1950.

The different tests covered in this study are

summarized in tables 17 and 18. The reader can

obtain a general idea of the characteristics of each

wood by reading across the tables and can compare

the individual properties of the different woods by

following the respective columns from top to

bottom.

It is apparent that in general utility the Puerto

Rican woods are equal or possibly superior to a

comparable number of hardwood timbers from the

United States or Europe. In general, the Puerto

Rican woods air-season more satisfactorily than

woods from the temperate zone, have equal or perhaps more favorable shrinkage properties, and

machine somewhat more satisfactorily. This is

clearly evident in the tables on machining characteristics, in which Honduras mahogany (caoba

hondurena)—a wood highly regarded in this respect—was rated considerably below a number of

Puerto Rican woods in most machining properties.
32 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

TABLE 17.—i^vinniary of physiral properties

Species

Achiotillo_ _

.A.guacatillo.

Algarrobo- _

Almacigo---

Almendra. _

Ausul)ü

Cairnitillo .

Caimitillo verde.

Capá blanco

Capá prieto

Caracolillo

Casuarina

Cedro hembra.

Ceiba

Cuciibano

Cupey

Espino rubial.

Eucalipto

Granadino

Guaba

Guajón

Guama

Guano

Guaraguao.

Guavabota.

Higüerillo

Jácana

Jagua

Jagüey blanco.

Jobo

Jusillo

Laurel amarillo.

Laurel avispillo.

Laurel geo

Laurel prieto

Laurel sabino.

Mago...

Mamey.

Mango..

María...

Maricao...

Masa

Moca ...

Motillo

Negra lora.

Nemocá

Nuez moscada.

Palo colorado.

Palo de hueso..

Palo de matos.

Specific

gravity

Percent

0. 39

. 42

. 70

. 29

. 59

. 82

. 68

. 64

. 66

. 57

. 77

. 81

. 45

. 2.3

. 65

. 67

.46

.51

. 61

. 59

. 54

. 62

. 22

. 51

. 73

. 62

. 74

. 66

. 40

. 41

. 74

. 55

. 47

. 45

. 45

.59

. 29

. 62

. 55

. 55

. 64

. 63

.63

. 80

. 70

. 62

. 59

«. 53

. 81

.50

Weight per cubic

foot

Green

Pounds

51

49

71

47

66

76

66

61

71

68

72

51

50

69

71

53

69

68

62

64

67

27

71

72

72

74

64

55

60

76

54

51

50

46

35

71

59

66

67

60

74

75

72

62

60

71

77

70

Air-dry ^

Pounds

29

33

53

22

44

64

52

49

49

42

58

64

34

17

50

52

35

42

46

44

41

46

17

38

47

59

51

30

31

56

41

36

34

34

44

21

54

41

43

48

48

47

61

54

47

44

59

61

37

Shrinkage from green to

ovendry

Radial

See tootnote.s at end oí table.

Percent

2. 9

4. 9

4. 4

2. 6

4, 5

6. 6

5, 9

5. 0

4. 3

3.5

5. 9

6. 4

4. 5

2. 1

5. 0

4. 7

4. 1

6. 2

2, 8

3, 6

4, 8

4. 0

3. 0

3. 8

6. 2

3. 0

7. 9

4. 6

2.9

2. 7

4. 8

3. 7

3. 9

3. 4

3, 6

3. 8

3. 2

7. 7

3. 0

6. 2

4.0

4. 8

3. 6

6. 7

6. 5

4. 9

4. 6

« 10. 1

6.3

3. 6

Tangential

Percent

5. 7

11. 3

8. 3

4. 2

5. 7

10. 1

7. 1

6. 4

8. 5

11. 7

6. 1

5. 2

9. 4

6. 3

13. 3

5. 7

6. 0

7. 7

6. 6

7. 6

7. 7

11. 2

6. 3

10. 7

9. 1

6. 4

4. 7

8. 0

6. 0

6. 9

5. 8

6. 4

6. 2

5. 2

15. 2

6. 1

8. 4

8. 2

7. 3

7. 1

10. 1

10. 0

7. 4

7. 0

«20. 6

8. 7

7. 4

Volumetric

Percent

8. 8

15. 9

12. 9

7. 3

10. 3

16. 3

13. 6

12. 7

11. 3

9. 8

14. 1

17. 6

10. 6

7. 1

13. 6

14. 1

10. 6

18. 9

8. 6

9. 6

12.5

10. 6

10. 7

11. 3

16. 9

9. 4

17. 9

13. 5

9. 3

7. 5

12. 7

9.6

10. 9

9.3

10. 0

9.8

8. 6

22. 0

9. 5

14. 3

12. 2

12. 0

10. 6

16. 3

16. 1

12. 3

11. 4

29. 1

14. 8

10. 9

Air-seasoning

characteristics

Rates '

M

M

M

R

R

R

R

R

R

M

M

M

R

M

M

Amount

of

degrade *

Resistance to

dry-wood

termites ä

M 9 VS

R 3 vs

M 3 VS

R 1 R

R 2 VS

S 1 vs

R •7 VS

M 2 VS

S 0 R

M 2 VS

S 1 MR

S 3 MR

S 1 VS

S 1 VS

M 2 VS

M 2 VS

M 2 VS

M 2 VS

M 3 MR

M 1 VS

R 1 MR

R 1 VS

M 3 VS

M 1 MR

S 3 VS

M 2 VS

R 1 MR

M 2 MR

M 2 MR

S 2 VS

M 9 VS

R 1 VS

S 3 VS

M 2 VS

S 2 VS

VS

VS

VR

VS

VS

MR

MR

VS

MR

R

R

VS

R

VS

VS
PUERTO RICAN WOODS

TABLE 17.—Hummary of physical propertien—Continued

33

bpecies

Panapén

Roble blanco

Samán

Tabaiba

Tabonuco

Teca

Ucar__

Yagrumo hembra

Yagrumo macho_

Weight per cubic Shrinkage from green to

foot ovendry

Specific

gravitv '

Tan- VoluGreen Air-dry ^ Radial gential metric

0. 27 38 20 2. 7 5. 7 8. 7

. 58 59 42 4. 1 5. 5 9. 7

. 44 68 32 2. 4 4. 2 6. 9

. 38 46 28 2. 4 4. 8 7. 1

. 53 52 40 4. 1 6. 4 10. 5

. 55 62 40 2. 1 3. 8 6. 2

. 93 79 69. 4. 4 7. 9 12. 2

. 29 41 22 2.0 6. 2 8. 3

. 36 40 28 4. 9 8. 2 12. 8

Air-seasoning

characteristics

Rates '

M

R

M

M

R

R

M

R

R

Amount

of

degrade *

Resistance to

dry-wood

termites ^

VS

vs

R

VS

vs

VR

R

VS

VS

1 Based on green volume and ovendry weight.

2 At 15 percent moisture content.

3 Rate of drying for l}é-inch lumber properl}-

under cover.

R—Rapid (11-17 weeks)

M—Moderate (18-26 weeks)

S—Slow (27 weeks or more)

•• Based on frequence and amount of cup, twist, bow,

crook, and end and surface checking occurring from green

piled to air-dry.

1—Minor degrade

2—Moderate degrade

3—Considerable degrade

^ VR—very resistant; R—resistant; MR—moderately

resistant; VS"—very susceptible.

° Approximate values.

TABLE 18.—Summary of iiKtchviing eharacteriMicH

Species Planing Shaping Turning Boring Mortising Sanding

Resistance

to screw

splittine

Achiotillo

Aguacatillo

Algarrobo

Almacigo

Almendra

Good

Exe

Fair

Good

V. poor

Good

__.do

---do

---do

Fair

Good

---do

Fair

Good

Exc

Good

Fair

---do

Good

---do

---do

---do

---do

do

Poor

---do

Good

V. poor

Fair

Exc

---do

---do

Good

---do

---do

---do

---do

---do

Poor

Good

--.do

Fair

Good

---do

Poor

Good

Fair

Poor

Good

Exc

Good

---do

Exc

Poor

Poor

---do

Exc

V. poor

Poor

---do

Good

---do

---do

Exc

---do

Good

Fair

---do

V. poor

Exc

Good

Poor

Good

Poor

--.do

Good

Poor

Fair

Exc

---do

Good

.--do

Exc

-..do

...do

Good

Poor

...do

Fair

---do

---do

do

Poor

...do

Good

V. poor

Fair

Exc

Good

...do

...do

Exc

Good

...do

--.do

...do

Fair

Good

...do

Fair

Good

...do

...do

Fair. .. ..

V. poor

Good

--.do

...do

...do

Exc

Fair

Good

Exc

Good

--.do

---do

---do

---do

Exc

Fair

Good

Poor

Good

---do

--.do

--.do

Exc.

Do.

Good.

Exc.

Good.

Ausubo

Caimitillo

Caimitillo verde

Caoba hondurena

Capá blanco

Capá prieto

Caracolillo

Casuarina

Cedro hembra

Ceiba

Cucubano

Fair.

Do.

Good.

Do.

Do.

Poor.

V. poor.

Good.

Exc.

Poor.

Cupey Good.

Espino rubial

Eucalipto __ _

Do.

Exc.

Granadino

Guaba

Guajón.

---do

---do

Fair

Good

V. poor

Good

Exc

-.-do

Good

Exc

Poor

Good

--.do

Poor

Good

V. poor

Fair

Exc

Good

Exc

...do

Poor

Good.

Do.

Do.

Guama

Guano

Good

V. poor

Good

---do

---do

---do

Exc

Poor

Exc

Fair

Exc

Poor

Fair

Good

--.do

---do

Do.

Exc.

Guaraguao

Guayabota

Higüerillo

---do

---do

Poor

Fair

Exc

Good

Good.

V. poor.

Poor.

Jácana Fair.

Jagua__ ___ Good

Jagüey blanco Exc.
34 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 205

TABLE 18.—l^uminnry of machining characteñstics—Continued

Species Planing Shaping Turning Boring Mortising Sanding

Resistance

to screw

splitting

Jobo Exc

Poor

...do

Good

...do

...do

Fair

Poor

Good

Fair

...do

Poor

Good

...do

...do

...do

...do

...do

V. poor

Exc

Fair

Good

...do

...do

Fair

Exc

Good

...do

...do

...do

Fair

Good

V. poor

Exc

Fair

...do

Good

...do

...do

Fair

Good

Poor

Good

...do

Fair

Good

Fair

Good

V. poor

Good

Fair

Poor

Good

...do

Exc

Good

...do

...do

...do

...do

...do

Fair

V. poor

Good

Poor

Fair

...do

Exc

...do

Fair

V. poor

Poor

Good

Exc

Good

Fair

...do

Good .

V. poor

Good

...do

Poor

Exc

Good

...do

Exc

Good

...do

...do

...do

Exc

Fair

V. poor

Exc

Fair

Poor

Fair

Good

Exc

V. poor

Poor

Poor

Good

...do

...do

...do

...do

..-do

V. poor

Good

...do

...do

Exc

...do

Good

...do

...do

Exc

...do

Good

Exc

Fair

V. poor

Exc

Good

Poor

Good

...do

Exc

Poor

Good

Fair

Poor

Good

V. poor

Fair

...do

...do

Poor

...do

...do

Good

...do

...do

Exc

Good

...do

...do

Exc

Fair

...do

Good

Poor

Exc

Good

V. poor

Good

V. poor

Good

...do

...do

Good.

Poor.

Laurel amarillo

Laurel avispillo

Laurel geo --

Laurel prieto

Laurel sabino

Good.

Do.

Do.

Do.

Do.

Exc.

Do.

Good.

María Do.

Good

Fair

Exc

Good

Fair

...do

...do

Exc

Poor

Good

Fair

...do

Good

Exc

Good

...do

Fair

Good

...do

Poor.

Masa Fair.

Good.

Motíllo Poor.

Fair

Nemocá

Nuez moscada

Palo colorado

Palo de hueso

Palo de matos

Panapén

Good.

Do.

Exc.

Fair.

Good.

Exc.

Roble blanco

Samán

Fair.

Good.

Tabaiba Do.

Tabonuco Do.

Teca

Ucar

Do.

V. poor.

Yagrumo hembra

Yagrumo machoExc.

Do.

A considerable number of the Puerto Kican

woods possess unusual attractiveness, fitting them

for a variety of uses where this property is important. This quality plus a wide range in density,

hardness, and .strengtli, among tlie woods tested—

from guano (balsa) at the lower level to ucar and

ausubo at the top—provides the consumer with an

extensive choice of woods for any specific purpose.

In general, one or more and frequently several of

tliese woods are suitable for most of the common

wood uses on the island. Their utilization to the

fullest extent possible in preference to imported

material would encourage better management of

the forests and, at the same time, would materially

benefit the local economy.
PART 2. TIMBER DESCRIPTIONS

ACHIOTILLO

Alchornea latifolia Sw. (spurge family, Euphorbiaceae)

Achiotillo (fig. 16) is a pale creamy-brown color

throughout, except for frequent reddish-brown

"resin ductlike" canals, which are alined in a radial

direction. On flatsawed surfaces, these blemishes

range in size from minute round specks to fairly

large ones and may be either filled with a opaque

brown substance, partly occluded, or open. The

wood has medium texture, straight to slightly

wavy grain, low luster, and lacks characteristic

odor or taste when seasoned. Growth rings are

not evident. The wood is fairly soft and moderately light, yet firm and strong for its weight of

29 pounds per cubic foot when air-dry and 51

pounds when green.

Achiotillo air-dries at a moderate rate. Green

lumber 1% inch thick dries to about 17 percent

moisture content in 5 months under cover in the

San Juan area. Moderate degrade occurs during

seasoning, mostly in the form of cup, bow, and

t-\vist, and a very small amount of surface checking. Sliced veneer stock is also reported to dry

satisfactorily with a minimum of checking and

splitting. Seasoning is accompanied by moderate

and fairly uniform shrinkage. Flatsawed boards

shrink at the rate of YIQ inch (0.9 percent) per foot

across the growth rings and Vs inch (2.4 percent)

per foot parallel to the growth rings from green to

air-dry.

The wood saws and works very easily in all machining operations. Good surfaces are obtained

in planing, but in most other machining operations,

because of the wood's moderate density and softness, it is badly torn and crushed and tends toward

fuzziness. Special care is necessary in machining to keep such defects to an acceptable minimum.

Screws and nails can be driven easily into the wood

with a minimum of splitting.

Achiotillo is very susceptible to damage by the

dry-wood termite and other insects, and it is

quickly destroyed by decay when in contact

with the ground. Logs are soon damaged by pinhole borers and discolored by sap-staining fungi

if the tree is not processed immediately after felling. Green lumber is also subject to blue stain

unless the surface is allowed to dry quickly after

sawmg or is treated with an antistain solution.

The wood is moderately strong for its density

and has unusually good bending qualities when

dry. Recent tests indicate it is very acceptable

for kite sticks and other small bent parts. It

may also be well suited for match splints, veneer

flatware, and other similar uses. Achiotillo lacks

the strength and durability for most outdoor construction but with presers'ative treatment woulcl

be useful for light carpentry and some types of

exterior construction. It is also suitable for

boxes, crates, toys, and temporary cement forms,

and it has been recommended for utility veneer in

British Guiana.

1 iU

1 inch

F—495323

FIGURE 16.—Achiotillo : Top, flatsawed ; bottom,

quartersawed.

35
36 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

AGUACATILLO

Meliosma herbertii Rolfe (sabia family, Sabiaceae)

Ao-iiacatillo (ñg. 17) has pale-browii heartwood,

often witli an attractive orange overcast, which

is not readily separated from the lighter colored

sapwood. Growth rings are faintly marked by

zones of darker colored tissne that appear on the

I'iidial surface as line scratches or lines, giving the

wood a rather attractive appearance resembling

cedro hembra. The wood has medium luster,

moderately coarse texture, and straight to frequently interlocked grain. Seasoned wood has no

distinctive odor and taste. Aguacatillo is moderately heavy, firm, and tough, weighing 33

1 inch

F-495324

FIGURE 17.—Aguacatillo : Top, flatsawed ; bottom,

quartersawed.

pounds per cubic foot when air-dry and 49 pounds

when green.

The wood seasons at a moderate rate but develops considerable degrade in the process.

Green 1% inch lumber requires 5 months to airdry to about 17 percent moisture content under

cover in the San Juan area. Seasoning is accompanied by considerable degrade. Cupping is particularly troublesome, along with a moderate

amount of bow, twist, crook, and surface checking. Sap-staining fungi are also active during

the early stages of drying unless the wood is

dipped in an antistain solution or is surface-dried

immediately after sawing.

Seasoning is accompanied by relatively high

and uneven shrinkage. Flatsawed lumber shrinks

at the rate of %6 ii^cli (2.5 percent) per foot across

the groA\i:h rings and % inch (7.5 percent) per

foot parallel to the growth rings in seasoning from

green to air-dry.

Despite the presence of silica in the wood rays,

aguacatillo saws and machines easily, but with

generally unsatisfactory results. It gives good

results in planing and can be sanded to a smooth,

even surface. The results are poor in most other

machining operations because of the wood's tendency to tear and crush in these operations. However, because of its softness and frequently interlocked grain, aguacatillo is rated excellent in

resistance to screw splitting. It should also accept

and hold nails well, glue satisfactorily, and take

a good polish.

Aguacatillo is very susceptible to termites and

other insects and poorly resistant to decay. The

wood's low durability, poor seasoning properties,

and difficulty in working hampers its utilization,

and the infrequent occurrence of aguacatillo and

the relatively small size of the logs also reduce

its importance as a commercial timber. However, it is attractive and suitable for furniture,

cabinetwork, paneling, interior trim, and other

decorative purposes if the user is willing to contribute sufficient time and care in machining and

sanding operations. It can also be used for boxes,

crates, general interior and exterior constniction,

and carpentry. In general, the wood should be

used only where high durability or great strength

are not essential.

ALGARROBO (COURBARIL)

Hymenaea courbaril L. (legume family, Leguminosae)

^Algarrobo (fig. 18), also known as courbaril and

West Indian locust, is one of the best known and

most useful woods of tlie American tropics. The

heurtwood is salmon red to orange brown in color

when freshly rut, I'lumging to russet, often with

dark streaks, upon seasoning and exposure.

Heartwood is distinct from sapwood. At times it

may have a golden luster. The white to gray sapwood is abnormally thick, particularly in rapidly

grown second-growth trees. Interlocked grain is
PUERTO RrCAN WOODS 37

characteristic, but occasionally straight grain is

seen. The wood is mostly medium textured and

Avithout distinctive odor or taste wlien seasoned.

Growth layers are not readily evident.

The wood is particularly attractive on the radial

surface, resembling sugar maple (Ace?- saccharum) in this respect. Its radial surface is distinguished by a lustrous sheen and scattered lines

of vessels. This is a very heavy wood, weighing

53 pounds per cubic foot when air-dry and 71

pounds when green.

Algarrobo is difficult to season. In the tests,

green lumljer seasoned at a moderate rate, requiring approximately 6 months to air-season to about

17 percent moisture content mider cover in the

San Juan area. Considerable degrade occurred

in the form of moderate cup, crook, and surface

checking, moder-ate to severe bow and twist, slight

end checking, and a moderate amount of

casehardening.

Shrinkage during seasoning is moderate in all

directions, especially for a wood of algarrobo's

density. It compares veiy favorably in this respect with black locust (Robinia pseudoacacia) of

the united States, which it noted for its low

shrinkage in relation to its high density. Green

algarrobo lumber shrinks 2/10 ^'^'^c^'^ (1-7 percent)

per foot across the growth rings and about y^Q inch

(3.5 percent) per foot along the growth rings in

drying to 15 percent moisture content. It is reported to absorb moisture rather ciuickly but is

considered reasonably stable in use.

The wood is very strong, tough, and hard, and

is superior in strength to white oak {Quercus

alba) of the United States in both green and

air-dry condition. It also compares favorably

with teak in most strength properties. Algarrobo

is moderately difficult to saw and machine because

of its high density, but except in planing it can

be machined to a smooth surface. The wood is

somewhat difficult to plane because of the tendency

to tear easily in pieces having roey grain. It is

difficult to nail but has good resistance to splitting

by screws; it takes glue well and finishes satisfactorily, but does not take a high polish. The wood

steam-bends very well, being comparable to white

oak in this respect.

Algarrobo is reported to be unusually variable

in decay resistance, ranging from nondurable to

very durable in contact with the ground. It is

readily damaged by marine borers but it is very

resistant to dry-wood termites, rating well above

the West Indian and Honduras mahoganies and

teca in this respect. The wood weathers badly,

and heavy checking occurs when the wood is exposed without the protection of paint.

j

1 inch F—495325

FIGURE 18.—Algarrobo: Top, flatsawed ; hoftoni,

quartersawed.

Algarrobo's high shock resistance fits it admirably for use in sporting goods and tool handles in

place of white ash [Fraxinus amertcana). It is

also quite suitable for steam-bent boat parts or

other similar items for which oak is generally used.

It provides a highly wear-resistant surface for

flooring and stair treads. Wood from the wide

layer of sapwood in second-growth timber is considered exceptionally good for natural and blondfinish furniture.

Both the sapwood and heartwood should be

particularly attractive as veneer and plywood as

well as for furniture, cabinetwork, interior trim,

and turnery. The wood is currently used in the

American tropics for ship planking, gear cogs,

wooden-wheel parts, heavy and durable building

construction, and loom harnesses. Because of its

high resistance to aln-asion, algarrobo is preferred

for sugar-mill and other mill-machinery parts,

lock gates in nonteredo areas, slioe heels, and ice

sheathing.
38 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

ALMACIGO (GUMBO-LIMBO)

Bursera simaruba (L.) Sarg, (bursera family, Burseraceae)

This tree is called almacigo in Puerto Rico and

gumbo-limbo in Florida. The logs are generally

short and often crooked, but they are usually available in medium to large diameters. Although sap

stain develops in freshly cut logs soon after the

tree is felled, it can be controlled if the logs are

milled immediately after felling and the lumber

is dipped in an antistain solution before piling.

Both the heart'R-ood and sapwood of almacigo are

a uniform cream to light-brown color throughout

(fig. 19). However, because of sap-staining,

almacigo is most often known as a wood of bluishgray color. The wood has fine texture, straight to

sometimes irregular grain, moderate luster, and

possesses no distinctive order or taste. Growth

rings are either absent or indistinct.

Seasoned wood is soft and light yet firm, tough,

and fairly strong for its weight. Almácigo's best

mechanical property is its good resistance to splitting. Air-dry wood weighs 22 pounds per cubic

foot and green wood about 47 pounds per cubic

foot at 17 percent moisture content.

1 inch

FIGURE 10.—Almacigo ; To¡j, flatsawed ; bott<ym

quartei-ijawed.

F-495326

Almacigo air-seasons rapidly with minor degrade in the form of very slight cup and bow and

slight twist. Crook, surface checking, and end defects are not troublesome. Green lumber 1%

inches thick air-seasons to about 18 percent moisture content in slightly over 4 months under cover

in the San Juan area. Exceptionally low shrinkage occurs during seasoning. Flatsawed boards

shrink approximately i/^ inch (2.1 percent) per

foot in width and % inch (2.1 percent) per foot in

thickness during seasoning.

The wood works easily with either hand or

machine tools but—except in planing and sanding—the surfaces are severely torn and crushed

in the machining operations. Although the wood

is rated good in planing and sanding, slight fuzziness may occur in both operations. The use of

very sharp, thin cutting edges and reduced feed

rates are required to reduce tearing and crushing

to a minimum. The wood has excellent resistance

to screw splitting, holds nails firmly without splitting, and can be stainecl and finished satisfactorily.

The logs are reported to peel well on rotary

lathes in Mexico without preliminary heating or

bark removal, although some logs produce veneer

with a "woolly" surface. Yield of acceptable face

veneer averages 30 to 40 percent. The veneer has

numerous pin knots, some mineral streaks, and

occasionally a "birds-eye" figure like that in sugar

maple.

Almacigo is very susceptible to termites and

other insects, very perishable in the soil, and

Eresumably has little resistance to marine borers,

ogs are subject to early and severe attack by

pinhole borers in addition to the above mentioned

sap-staining fungi. However, both heartwood

and sapwood are easily impregnated with preservatives, giving the wood good resistance to

decay and insects.

Almacigo does not possess sufficient attractiveness and strength for use in furniture, but it is

recommended for boxes, crates, cement forms,

interior carpentry, and all types of light construction. It has been used for match splints in

Jamaica. Despite almácigo's relatively poor

machining qualities, the wood's low and miiform

shrinkage indicates that it may be suitable for

patternmaking and other similar uses where a

lightweight, easily worked, and stable wood is

required. In some areas the principal use of the

tree is for posts and poles which take root and

develop into living fence posts and telegraph

poles.

The wood is used for utility plywood in Mexico

under the name "Mexican white birch" ; it is also

considered a good material for core stock. In

general, almacigo can be used as a substitute for

pine or other lightweight conifers but lacks the

strength of these woods.
PUERTO RICAN WOODS 39

ALMENDRA

Terminalia catappa L. (combretum family, Combretaceae)

Almendra, or Indian-almond, has become

naturalized in Puerto Rico and elsewhere in tropical America. The seasoned lieartwood is a

medium reddish brown, marked with slightly

darker colored stripes (fig. 20). The sapwood is

indistinct and somewhat lighter in color. The

grain is generally irregular and often interlocked;

texture medium; luster rather high. A slight

odor is often noticeable in seasoned wood. Long,

narrow zones of tension wood occur often and

cause considerable trouble in machining operations. The wood is moderately heavy, weighing 44

pounds per cubic foot when air-dry and 66 pounds

when green. It is moderately strong, hard, and

tough.

The wood seasons rapidly, l^g-inch green lumber reaching approximately 18 percent moisture

content in slightly over 3 months under cover in

the San Juan area. A moderate amount of warping occurs during seasoning, but surface and end

checking are almost absent under the usual drying

conditions.

Shrinkage is moderate and uniform during seasoning, indicating that almendra should be stable

after manufacture. Green lumber shrinks at the

rate of % o inch (1.8 percent) per foot across the

growth rings and %o inch (2.5 percent) per foot

along the growth rings during seasoning to 15

percent moisture content.

Almendra saws and machines rather easily, but

Avitli generally misatisfactory results. Tom and

fuzzy grain is very common in planing, shaping,

and turning, especially in pieces containing tension wood or irregular grain. Rough and torn

grain is also common in boring and mortising. It

sands to a fairly good surface and has good resistance to screw splitting. Careful machining is

necessary to keep machine defects to an acceptable minimum for most uses.

Almendra is very susceptible to dry-wood

termites. On the basis of tests on closely related

species, it should be durable in contact with the

ground but probably is quite susceptible to attack

by marine borers.

The wood is very attractive when finished and

would be useful for millwork, furniture, veneer.

''^U^iWh

''''fni:§. K']

\ inch

F-495327

FIGURE 20.—Almendra : Top, flatsawed ;

bottom, quartersawed.

and cabinetwork if carefully handled. If almendra possesses the durability of other species of the

genus, it should be acceptable for many i;ses in

exterior construction that require a moderately

strong, hard, durable wod. It has been recommended in other Caribbean areas for framing,

planking, and other parts of boats; general construction, bridge timbers, railway crossties, and

flooring. It is also used to some extent for boxes,

crates, and other shipping containers.

AUSUBO (BALATA)

Manilkara bidentata (A. DC.) Chev. (sapodilla family, Sapotaceae)

Ausubo, also known as balata, is one of the

strongest and most attractive woods available for

commercial use in Puerto Rico. The whitish to

pale-brown sapwood (fig. 21) is distinct but not

easily separated from the heartwood. Green

heartwood is light red when cut, turning to a darkreddish color when dry. The wood has a uniformly fine texture without pronounced figure ; the

grain is usually straight but may be coarsely interlocked at times. A characteristic odor is sometimes present in green wood but is not evident after

seasoning, although dry wood does have a characteristic oily feel. Ausubo is exceptionally hard

and heavy, weighing 64 pounds per cubic foot

when air-dry and 75 pounds when green.
40 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 205

&

¡'04,,

V- »?"(

FIGURE 21.

L

1 inch

F—195328

-Ausubo : Top, flatsawed : bottom.

quarter.sawed.

Despite its density, ausubo air-seasons at a

fairly rapid rate, reaching an air-dry moisture

content of 19 percent in 4 months under cover in

the San Juan area. Seasoning degrade is limited

to a small amount of cup and bow and slight twist.

Surface checking and end splitting were not evident in the tests.

Ausubo undergoes moderate shrinkage for a

wood of its density. Green wood is reduced approximately %o ii^cb (2.5 percent) per foot of

width across the growth rings and %6 ""^^h (4.5

percent) per foot along the growth rings in seasoning to 1.5 percent moisture content.

Ausubo is moderately hard to machine because

of its high density but cuts cleanly in ripping and

crosscutting without appreciable dulling of the

cutting edges. The wood gives good to excellent

results in most machining operations except turning, which must be done slowly and carefully to

avoid tearing and rough surfaces. It is also difficult to nail and is susceptible to splitting by

screws. Ausubo is an excellent wood to steambend, comparable to oak in this respect, but is

difficult to glue. It finishes beautifully and rather

easily, the finished wood resembling mahogany.

The wood is considered very resistant to decay,

very susceptible to marine borei'S, moderately resistant to clry-wood termites, and very resistant to

subterranean termites. Pinhole borers will attack the sapwood of green logs if left in the woods

for several we«ks, and powderpost beetles may

damage the sapwood after seasoning. Sap-staining fungi are not troublesome during seasoning.

Ausubo does not weather well ; it develops severe

checks when exposed to the weather without the

protection of paint.

This wood is one of the strongest growing in the

American tropics, equaling greenheart (Ocotea

rodiaet) in most strength properties and exceeding

white oak in all I'espects except resistance to splitting. Ausubo's excellent steam-bending properties make it well fitted for boat frames and other

bent work. The wood's fine texture, straight grain,

high density, and good finishing properties qualify

it for use in shuttles, loom harnesses, and other

textile items, billiard cues, violin bows, and furniture. Its gi'eat strength and high resistance to

wear recommends it for use as ice sheathing, boat

frames, mill rollers, keel shoes, and pulpmill equipment such as beater liners, bed plates, and alligator bars.

Ausubo is also used extensively for railway ties,

utility poles, ax and tool handles, heavy construction, flooring, and bridge work. It is used very

sat isfactorily in many areas for all types of furniture cal)inetwork because of its attractiveness,

great sti-ength, and good finishing qualities. The

wood is also highly recommended for flooring,

bench tops, and stair treads in industrial plants

and machine shops.

CAIMITILLO

Micropholis chrysophylloides Pierre (sapodilla family, Sapotaceae)

The heartwood (fig. 22) of caimitillo, or mesa,

is a uniform light yellowish brown without pronounced figure. Seasoned wood resembles that of

sugar maple and yellow birch {Befvla aJJeghanien-

•v/.v) in appearance. Tlie sapwood is lighter in

color and not clearly diiïerentiated from the heart-

\vo(xl. Growth rings are indistinct. The wood

has uniformly fine texture, straight gcdui, inedium

luster, and is ordorless and tasteless. Air-dry

wood \\eighs about 52 pounds per cubic foot and

green wood 66 pounds per cubic foot.

Caimitillo air-seasons rapidly, reaching 17 percent moisture content in 4 months under cover in

tlie San Juan area. Only minor degrade occurs

during seasoning, in the form of slight bow. No
PUERTO RICAN WOODS 41

surface or end checking, casehardening, or other

defects were apparent in the study.

Shrinkage is moderate and very uniform for a

wood of caimitillo's liigh density. Green wood

shrinks y^g ^^^ch (2.6 percent) per foot across the

growtli rings and sliglitly over y^g incli (3.6 percent) per foot along the growth rings in seasoning

to 15 percent moisture content.

Silica in the wood makes sawing and machining moderately diíRcult and causes a rapid dullmg

of saw teeth and cutting edges. However, caimitillo machines to a glassy-smooth surface in most

operations. It is rated good to excellent in all

woodworking operations except sanding. The

typically straight-grained material shows

scratches readily in sanding. Also, it splits

easily when screws or nails are driven unless

adequately sized lead holes are used. Caimitillo

finishes smoothly and takes a high polish.

The wood is hard, strong, and tough, resembling

sugar maple and yellow birch in strength properties. It is considered moderately resistant to drywood termites and decay and has little resistance

to marine borers, based on tests in Hawaiian

waters.

Caimitillo is an excellent wood for furniture,

cabinetwork, interior trim, flooring, paddles, agricultural implements, and tool handles. Its close

resemblance to sugar maple and yellow birch

should make it suitable for veneer and plywood

and for numerous other purposes for which those

species are commonly used. The wood is also well

suited for all types of interior and exterior construction, and general carpentry, and for piling

in nonteredo areas.

, ' "': ^' ' : ' ■■

Í

MS*.-7K-.^JHafeVA V «^ '

f ^*

Ú/iL- -, Jn.^

inch

F-495329

FIGURE 22.—Caimitillo : Top, flatsawed ; hoftom, quartersawed.

CAIMITILLO VERDE

Micropholis garciniaefolia Pierre (sapodilla family, Sapotaceae)

Caimitillo verde (fig. 23) is very similar to

caimitillo in appearance and physical properties,

the two woods being almost inseparable when

mixed. The heartwood is a uniform light yellowish brown and not readily separated from the

lighter colored sapwood. The Avood is similar

to that of sugar maple in general appearance but

tends to be somewhat darker in color. It has uniformly fine texture, straight grain, medium luster,

and is odorless and tasteless. Growth rings are

not distinct. The wood is moderately heavy,

weighing about 49 pounds per cubic foot when

air-dry and 61 pounds when green. In comparison, sugar .maple weighs 44 pounds when

air-dry.

Caimitillo verde air-seasons rapidly with

moderate degrade. Green lumber seasons to

about 18 percent moisture content in 3 months

under cover in the San Juan area. Degrade consists of a moderate amount of warping and almost

no surface or end checking. Shrinkage is especially low and uniform for a wood of caimitillo

verde's density. From green to air-dry, green

lumber shrinks at the rate of 14 inch (2.1 percent)

per foot across the growth rings and % inch (3.4

percent) per foot parallel to the growth rings.

The wood is moderately diíRcult to saw and

machine, because of high density and the presence of silica that rapidly dulls saw teeth and

cutting edges. However, caimitillo verde machines with good to excellent results in all opera-
42 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 205

L

1 inch

F-495330

FIGURE 23.—Caimitillo verde : Top, flatsawed ; hottom,

quartersawed.

tions. It also has a good resistance to screw

splitting and should take nails equally well, generally somewhat better than caimitillo (mesa)

in this respect. The wood finishes very smoothly

and takes a high polish.

Caimitillo verde is hard, strong, and tough,

resembling sugar maple in these properties. It

is considered very susceptible to dry-wood termites, as compared with caimitillo (mesa) which

is rated moderately resistant. Its similarity to

caimitillo otherwise would indicate the wood is

moderately resistant to decay and very susceptible

to damage by marine borers.

This Avood is suitable for most of the same

products that sugar maple and yellow birch are

used for in the United States, particularly veneer,

and plywood, furniture, cabinetmaking, turning,

interior trim, flooring, agricultural implements,

and tool handles. It should also give good service in all types of interior and exterior construction, piling in nonteredo waters, and in general

carpentry. Caimitillo verde is one of the highest

quality woods growing on the island, and it should

be used for purposes that utilize its superior

decorative and strength properties.

CAOBA HONDURENA (HONDURAS MAHOGANY)

Swietenia macrophylla King (mahogany family, Meliaceae)

More caoba hondurena is used in furniture

manufacture in Puerto Kico than any other wood.

It is obtained in the form of rough air-dry lumber from Mexico. The tree is not native to

Puerto Rico but has been planted extensively in

the Luquillo Mountains and to a lesser extent

in other areas. Occasionally limited amounts

of small-size plantation-grown logs are available

for commercial use. The tree grows well when

planted on the proper sites, but it is easily uprooted during hurricanes and may never become

available in large quantities. The tree and wood

are called caoba hondurena, Mexican mahogany,

a-nd Honduras mahogany in Puei-to Rico.

The heartwood (fig. 2-i) is pinkish to salmon

colored Avhen freshly cut, later becoming light

reddish brown with a golden luster. The yellowisl^-wliite sapwood is generally 1 to 2 inches wide

niui clearly demarcated from the heartwooti. The

grain is commonly interlocked, producing a wide

attractive stripe figure on quartersawed surfaces.

Occasionally a mottled, fiddleback, raindrop,

roey, or curley figure is present. The texture of

the wood is medium to rather fine and uniform.

Growth layers are indistinct. Seasoned heartwood is without characteristic odor or taste.

Much of the caoba hondurena used in Puerto

Rico contains tension wood composed of soft gelatinous fibers that are conducive to excessive longitudinal shrinkage and increased internal stresses

during seasoning. This causes increased warping

during seasoning and the development of fuzziness during sawing and other machining operations.

Plantation-grown wood averages about 31

pounds per cubic foot when air-dry and 40 pounds

when green. Forest-grown wood is slightly

heavier, weighing about 44 pounds per cubic foot

green and 38 pounds air-dry.

Caoba hondurena seasons rapidly and with very

minor degrade unless tension wood is present.
PUERTO RICAN WOODS 43

The wood is world-renowned for its unusually low

and uniform shrinkage and good stability after

manufacture. It is considered one of the few

nonrefractory woods in the world. However,

pieces containing tension wood develop considerable cup and bow and are subject to distortion during manufacture.

Caoba hondurena is one of the easiest and most

satisfactory woods to work with, either with machine or handtools, and has very little dulling effect on cutting edges. However, as already

mentioned, the presence of tension Avood is troublesome in some pieces and requires the use of very

sharp cutting edges. The wood is easy to glue,

takes nails and screws well, and can be given an

excellent polish by an}^ of the accepted methods.

It is one of the most satisfactory woods to slice or

rotary-cut into veneer, although flitches frequently develop cracks unless properly boiled. A 60-

hour boiling process, starting with a cold

soaking and followed by gradual increase of temperature to 170° F., is recommended.

The heartwood is resistant to decay and moderately resistant to dry-wood termites, tjut it is quite

vulnerable to marine borers. The sapwood is

very susceptible to both insects and decay. Logs

may be damaged by pinhole and flathead borers if

not protected by insecticides soon after felling.

The wood possesses excellent weathering characteristics; only minor surface checking develops

when it is exposed to the weather without the protection of paint. It is highly resistant to impregnation with preservatives.

Caoba hondurena is extremely strong for its

weight and was used extensively at one time for

airplane propellers. It is one of the most popular

cabinetwoods known, and its use is generally confined to the more expensive tyi^es of furniture and

cabinetmaking, interior trim, paneling, and similar products. The wood is used extensively in

burial caskets, interior work of boats and ships,

and turning, and in several types of musical inI,', j

'I iffÄiä||P

'^"mpn'i'i

I inch F-495331

FIGURE 24.—Caoba hondurena ; Top, flatsawed ;

hottom, quartersawed.

struments, particularly pianos. Its characteristic

low and even shrinkage, stability after manufacture, and ease of working make it particularly

valuable for molds, dies, and patternmaking.

However, the largest volume is still used for face

veneer, often with a core or backing of cedrela or

other less valuable woods.

CAPA BLANCO

Petitia domingensis Jacq. (verbena family, Verbenaceae)

Capá blanco is a timber of excellent quality and

unusually attractive appearance (fig. 25). The

light-brown to medium-brown heartwoocl is frequently variegated in different brownish hues or

is marked by attractive darker colored waxy looking stripes. The sapwood is lighter brown and not

clearly separated from the heartwood. The wood

possesses rather fine grain, which may be straight,

somewhat wavy, or interlocked. Luster is medium

to high, growth rings are not visible, and odor and

taste are not distinctive. It is a very hard, heavy,

tough, and strong wood, weighing about 49 pounds

per cubic foot when air-dry and 71 pounds when

green.

The woocl air-seasons rapidly with only moderate degrade. Green lumber air-dries to slightly

below 18 percent moisture content in 4 months or

less under cover in the San Juan area, and degrade

is limited to a moderate amount of bow and twist

and very slight cupping. Other types of seasoning

defects are of little importance. Shrinkage is

moderate and uniform during seasoning, indicating that the wood should be relatively stable after

manufacture. Green lumber shrinks i/g inch (1.2

percent) per foot across the groAvth rings and i/4

inch (2.2 percent) per foot parallel to the growth

rings during seasoning to 15 percent moisture

content.
44 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

_i

1 inch

F-495332

FIGURE 2.").—Capá blanco: Top, flatsawed ; bottom, quarteisawed.

Capá blanco is moderately easy to work. Good

to excellent surfaces are obtained in all machining

operations except planing, in which considerable

"pickup" or torn grain occurs where interlocked

grain is present. The wood otherwise planes and

machines in other operations to a glossy smooth

surface; it glues well, takes a high polish, and

accepts nails or screws with a minimum of splitting.

Capá blanco heartwood is moderately resistant

to dry-wood termites and moderately durable in

contact with the ground. Sap-staining fungi are

not troublesome in the log or during the seasoning

of sawed products.

The wood is sufficiently attractive for use in

furniture, cabinetmaking, turned articles, novelty

items, interior paneling, and similar uses. The

finished wood resembles black walnut {Juglans

nif/ra) of the United States in color and pleasing

appearance. It has been used in the Caribbean

area for rollers in coffee-hulling mills, for making

carts, and for posts, poles, piling, and props. The

wood appears to be suitable for all types of agricultural implements, handles, sporting goods, and

other products requiring an attractive, strong, and

durable wood. Knotty and low-grade material

would be suitable for all types of light and heavy

construction, including housing, farm buildings of

all types, bridge material, and reinforcing for

concrete work. The wood may be somewhat

troublesome to peel or slice into veneer, because of

the frequent occurrence of wavy and roey grain.

CAPÁ PRIETO

Cordia alliodora (Ruiz & Pav.) Oken (borage family, Boraginaceae)

Capá prieto is an attractive, durable, and muchused wood throughout the American tropics (fig.

26). Tlie freshly cut heartwood is light greenish

broAvn to olive brown in color, frequently with

darker streaks. Seasoned wood becomes a pale

golde]i brown to brown, and the darker streaks

become more prominent. Growth rings are delineated by narrow dark lines of pores, which

show as darker colored streaks on a quartersawed

(radial) surface and as wavy undulating lines on

a flatsawed ( tangential ) surface. Small dark rays

give the wood a lightly mottled appearance on

quartersawed surfaces.

The sapwood is lighter in color than tlie heartwood and not clearly delineated from it. The

grain is generally straight, texture is fine to mostly

medium, and luster is medium to high. Odor and

taste are generally lacking except for certain

darker colored wood from very old, large trees,

which may have a distinct spicy odor. Capá

prieto is a moderately heavy wood, weighing 42

pounds when air-dry and 68 pounds when green.

The wood seasons at a moderate rate. Green

lumber ly^ inches thick air-seasons to about 18

percent moisture content in 4 to 5 months under

cover in the San Juan area. Degrade during seasoning is limited to a moderate amount of warping. Surface checking and end splitting were not

evident in the study.

Shrinkage is moderate and uniform during seasoning. Green wood is reduced about Vs i^ich (1.0

percent) per foot in width across the growth rings
PUERTO RICAN WOODS 45

and 1/4 inch (2.0 percent) per foot parallel to

the growth rings on becoming air-dry.

Capá prieto saws and machines easily, with good

to excellent results. The wood's tendency to split

when screws and nails are driven can be overcome by preboring and the use of proper size lead

holes. It is reported to be an excellent wood to

glue and to hold its place well when manufactured. The wood is moderately strong and hard,

resembling Mexican mahogany in this respect.

Capá prieto is resistant to dry-wood termites,

rating slightly above Mexican mahogany in this

respect ; it is very durable in the ground, but very

susceptible to attack by marine borers. Darkcolored wood is believed to be more durable than

the lighter colored wood. Unpainted wood

weathers well when exposed without the protection

of paint. Only very slight checking occurs after

several years' exposure to the elements.

Because of its ease in working, good durability,

low shrinkage, and attractiveness, capá prieto is

used extensively for furniture, cabinetwork, millwork, general construction, bridge timbers, ship

decking, and general indoor and outdoor construction. It should also be useful for veneer,

plywood, boat planking and other boat parts,

turnings, and instruments. The wood's high

durability should qualify it for many of the same

uses as cedro hembra and mahogany, but it is

probably most valuable for decorative purposes.

1 inch

F—Í95333

FIGURE 26.—Capá prieto: Top, flatsawed ; bottom, quartersawed.

CARACOLILLO

Homalium racemosum Jacq. (flacourtia family, Flacourtiaceae)

Caracolillo is an exceedingly heavy, hard, strong

wood—but is not particularly attractive. The

heartwood ranges from grajdsh brown to reddish

brown (fig. 27), frequently with irregular streaks

and patches of darker brown. The sapwood is

an attractive golden yellow that merges gradually

into the darker heartwood. The wood has fine

texture, interlocked grain, and is without distinctive odor or taste when seasoned. Air-dry wood

weighs 58 pounds per cubic food and green wood

about 72 pounds at 50 percent moisture content.

The wood seasons at a moderate rate, reaching

an air-dry moisture content of about 18 percent

in 6 months under cover in the San Juan area.

Moderate degrade occurs during seasoning in the

form of very slight cup, end and surface check596033 O—61 4

ing, and crook, slight twist, and moderate bow.

Directional and volumetric shrinkage is moderate

for a wood of caracolillo's density. Green wood

undergoes about 1/5 inch (1.8 percent) shrinkage

per foot in width across the gi'owth rings and %

incli (0.1 percent) per foot in width parallel to

the growth rings in seasoning to 15 percent moisture content. Caracolillo is reported to be stable

after manufacture.

Caracolillo is moderately difficult to machine

because of its density, but it can be worked to a

glossy smooth finish in all machining operations.

However, the wood has poor resistance to screw

splitting unless adequate-sized lead holes are used.

It takes stain, paint, and varnish satisfactorily

without a filler and should also glue satisfactorily.
46 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 205

%\

The lieartwood has considerable resistance to

dry-wood termites, rating well above Mexican mahogany in this quality. Although the wood's

durability rating in tne ground or when submerged in teredo-infested waters is not known, it

is presumably not high.

Caracolillo is suitable for flooring, furniture,

cabinetwork, turning, and other decorative uses.

The wood's high strength, hardness, and straight

but interlocked grain indicates that it would be

suitable for tool handles, sporting and athletic

goods, agricultural implements, boat frames, keels

and underwater structural members of boats, and

similar uses. It is also suitable for heavy construction of all types wherever a heavy, strong

material is required.

P

j

1 inch

F-4953S4

FIGURE 27.—Caracolillo : Top, flatsawed ; bottom, quartersawed.

CASUARINA

Casuarina equisetifolia L. (casuarina family, Casuarinaceae)

Casuarina is commonly called Australian-pine

because of its needlelike leaves and its native habitat in. Australia. The tree is planted extensively

in the lower mountain regions of Puerto Rico,

where it makes excellent growth. Trees frequently grow to 15 inches in diameter and 140

feet tall in 15 to 20 years after planting. Clear

boles up to 100 feet long are common on the

better sites.

The wood is very hard and heavy, and exceptionally strong and tough. Its heartwood is a

dull reddish brown, occasionally with dark brown

to ahnost black streaks at irregular inter\'als (fig.

28), and not easily separated from the pinkish

sapwood. The wood has a very fine texture and

medium luster, and tightly interlocked grain is

characteristic. Gi'owth rings are not easily distinguished. Air-dry wood weighs about 64

pounds per cubic foot and green wood 72 pounds

per cubic foot at -12 percent moisture content.

The wood dries at a moderate rate and undergoes considerable degrade during the process.

Green lumber lYg inches thick air-dries to about

18 percent moisture content in 5 months under

cover in the San Juan area. Seasoning is accompanied by severe cupping and surface checking

and lesser amounts of other external defects.

Some casehardening may also oc«ur under the

usual drying conditions.

Seasoning is accompanied by heavy and relatively uneven shrinkage. Green wood shrinks at

the rate of i^ inch (2.4 percent) per foot in width

across the growth rings and % inch (5.8 percent)

per foot across the growth rings in drying to 15

percent moisture content. However, longitudinal

shrinkage (0.04 percent) is surprisingly low for a

wood with such tightly interlocked grain.

Casuarina logs are very difficult to saw in small

circular sawmills. Circular saws tend to heat.
PUERTO RICAN WOODS 47

chatter, and veer off course, producing lumber so

consistently off'size that it has little, if any, market

value. Because of its density and hardness, airdry casuarina lumber is also difficult to macliine.

However, machined surfaces are usually of fairly

good quality.

Some difficulty is encountered in machining, because of the frequent "pickup" that occurs in planing and the tearing and roughened surfaces that

developed in turning under normal operating conditions. Where these defects are not present, the

wood macliines to a glossy smooth surface. It is

rated as a good wood for boring and mortising,

and it sands to a very smooth finish. Because of

its tiglitly interlocked grain, it has exceptionally

good resistance to screw splitting for a wood of its

high density. AYell-finished wood is attractive but

lacks the distinctive figure preferred in furniture,

cabinetwork, and other decorative uses.

Casuarina is very susceptible to damage by drywood termites and only slightly durable in the

ground. But, on the basis of short-term tests in

Puerto Rico, it can be effectively and simply

treated with preservatives by the hot and cold

bath process.

Casuarina is used principally in Puerto Rico for

fence posts and poles, tobacco barns, and other

structures. It should be suitable for utility poles

and piling in nonteredo areas and for many other

uses where an extremely hard, dense, wood is required. Because of extreme difficulty in sawing,

casuarina is limited mainly to uses for which round

or hewn material is acceptable, although it may

be feasible to square logs in the mill for use in

heavy construction.

FIGURE 28.-

1 inch

-Casuarina : Top, flatsawed

quartersawed.

F-495335

dottom,

CEDRO HEMBRA (CENTRAL AMERICAN CEDAR)

Cedrela odorata L. (mahogany family, Meliaceae)

Cedro hembra is the most important timber for

general domestic use in tropical America, but the

supply is very limited in Puerto Rico. Most of the

local logs are short and of sinall diameter. Both

the tree and wood are widely known as Spanisli

cedar or Central American cedar.

The heartwood (fig. 29) is pinkish to reddisli

brown when freshly cut, becoming a uniform red

or dark reddish brown, occasionally with a purplish tinge, after exposure. The darkest colored

wood comes from the drier exposures. The sapwood is whitish gray or pinkish and sharply delineated from the heartwood. Growth rings are

clearly marked by narrow lines of darker pores,

which are visible on both quartersawed and flatsawed surfaces. A pleasing figure is provided by

these scattered vessel lines that stand out on an

otherwise plain surface. The luster is fairly high,

often described as a satiny sheen, and the texture

IS medium and uniform. The wood is straight

gramed and easily split. A cedarlike odor is

usually apparent, and at times a bitter taste is

evident in seasoned wood.

Two distinct types of wood are recognized in

some areas and may be represented in Puerto Rico.

One is a dark variety that is more straight grained,

coarser textured, and has more volatile oil: the

other is lighter colored, not so straight grained,

and has finer texture, lower luster, and less volatile oil. The weight of the wood varies considerably according to site, age of tree, and rapidity of

growth. Wood cut in Puerto Rico averagecl 34

pounds per cubic foot when air-dry and 51 pounds

in the green condition.

Cedro hembra seasons at a rapid rate with only

minor degrade. Green li/g-inch lumber air-seasons

to 20 percent moisture content in 4 months urider

cover in the San Juan area. The air-dry moisture

content of 20 percent is unusually high for a wood

of moderate density. Seasoning degrade is usually

limited to a small amount of warping in the form

of cup, bow, and twist. Surface checking and
48 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

,'\,\\ lil

1 inch

P-495336

FIGURE 29.—Cedro hembra : Top, flatsawed ; lotfoiii,

quartersawed.

other external defects Avere not observed in the

study.

In kihi-.seasoning, some pieces are liable to distort or collapse, and splits may occur along knots

unless low temperatures are used. Successful kiln

schedules for this species have been developed by

the Forest Products Research Laboratory, Princess Risborough, England, and by the Indonesian

Forest Research Institute.

Cedro hembra undergoes relatively low and uniform .shrinkage during seasoning and stays in

place very w^ell after manufacture. Green wood

shrinks % inch (2.1 percent) per foot in width

across the growth rings and y^ inch (3.0 percent)

per foot width parallel to the growth rings in seasoning to 15 percent moisture content.

The wood works very easily with both hand and

power tools, giving good results in planing, shaping, mortising, and sanding. It is a fairly good

wood to turn but is difficult to bore; torn and

roughened grain occur in these operations. The

presence of gum in some material gives trouble in

polishing but, in general, the wood stains and

polishes l3eautifully after suitable filling. It has

good nail- and screw-holding properties, is easy

to glue, and is a fairly good bending wood. Cedro

hembra is very popular in the veneer and plywood

industry, because it peels cold, dries exceptionally

well, and has good glueing properties. A slight

tendency for wooly surfaces to occur in veneering

is overcome by maintaining sharp edges on all cutting surfaces.

Cedro hembra is slightly inferior to Honduras

mahogany in most strength properties but is, in

general, a relatively strong W'ood for its weight.

It is considered more resistant to dry-wood termites than Honduras mahogany, rating resistant

as compared to moderately resistant for that species. However, the wood is sometimes attacked by

pinhole borers and has low^ resistance to attack by

marine borers. It is rated moderately durable to

durable in resistance to decay in contact with the

ground. Both logs and lumber are subject to sapstaining fungi. The wood possesses excellent

weathering properties when exposed to the elements without the protection of paint.

In the countries w'here it grows, cedro hembra

is the most extensively used wood for general construction and carpentry of all types, and for face

and core veneer for decorative and utility grades

of plywood. The heavier grades are suitable for

the same uses as Honduras mahogany. The wood

is also particularly well suited for pattei'nmaking,

Venetian blinds, decking and ¡blanking for small

boats, musical instruments, doors, paneling, shingles, flooring, and cigar boxes. It is usecl extensively in the American tropics for furniture,

millwork, boat parts, both interior and exterior

decoration, and for general and durable

construction.

CEIBA

Ceiba pentandra (L.) Gaertn. (bombax family, Bombacaceae)

Ceiba, also known as the silk-cotton tree, is an

exceedingly lightweight wood (fig. 30) resembling

guano (balsa) in appearance, and at 17 pounds

per cubic foot air-dry weighs the same as that

species. Green wood "weighs 50 pounds per cubic

foot at '24 percent moisture content. The dry

wood in its natural state is a very light brown, but

it is nearly always turned to blue gray by sapstaining fungi. The sapwood is the same color

and difficult to distinguish from the heartwood.

The wood has coarse texture, straight grain, and

low luster; it is without distinctive odor or taste.
PUERTO RICAN WOODS 49

Green wood air-seasons to about 18 percent

moisture content in 6 months under cover in the

San Juan area. This moderately rapid rate of

seasoning is accompanied by moderate degrade in

the form of a small amount of waq^ing and

moderate surface checking.

Shrinkage is low but somewhat uneven during

seasoning. Green Avood is reduced about i/in

inch (0.8 percent) per foot across the growth

rings and 1/3 inch (3.2 percent) along the growth

rings in the air-drying process. Its longitudinal

shrinkage of 0.22 percent is fairly high for a wood

without interlocked grain.

Ceiba machines easily but not satisfactorily. It

can be sawed almost without effort but tends to

develop fuzziness in both ripping and crosscutting. The wood gives excellent results in planing and sanding, and in resistance to screw

splitting, but it is difficult to shape, bore, turn,

and mortise because of its tendency to tear in these

operations.

Both the logs and lumber are very susceptible

to attack by insects and decay. Logs left in the

forest for any length of time discolor and decay

rapidly and are very quickly riddled by insects.

The lumber, as mentioned earlier, is almost always

turned blue gray by sap-staining fungi unless

dipped in a fungicide solution soon after sawing.

The tree is better known for its kapok than for

the soft, nondui'able wood it produces. The floss

surrounding the seeds of this tr'ee is collected by

natiA-es in Central America (rarely in Puerto

Rico) and sold on the export market as kapok.

This product is used extensively in buoys, life

belts, life-saving jackets, and for stuffing pdlows,

cushions, and similar articles.

Ceiba possesses low strength in proportion to

its low density but is still about twice as sti'ong

as guano (balsa). The wood is suitable for boxes,

slack cooperage, toys, light construction, and

:f-Hh'\-\f . ^'

1 inch

F—¡95337

FIGURE 30.—Ceiba: To/), flatsawed ; fjottom. qnartersawed.

numerous other products requiring a light, soft,

easily worked wood. Ceiba's similarity to guano

may qualify it for many uses where the heavier

grades of this wood are acceptable. It should also

be acceptable for patternnu\king, plywood cores,

and utility-grade plywood.

CUCUBANO

Guettarda laevis Urban (madder family, Rubiaceae)

Cucubano is aii attractive and useful wood but

generally available only in small-diameter logs

from the Puerto Rican' forests. The heartwood

(fig, 31) is an attractive pale yellowish brown to

golden brown, often streaked or variegated with a

darker brown. The sapwood is cream to very light

brown and not clearly delineated from the heartwood. The wood has good luster, fine texture, and

generally straight to occasionally interlocked

gram. Growth rings are very faintly marked by

somewhat darker colored tissue. Odor and taste

are not distmctive in seasoned wood.

Tlie wood is moderately hard, strong, and heavy,

weighing 50 pounds per cubic foot when air-dry

and (»D pounds when green. On tlie basis of tests

of closely related species, cucubano possesses

strength properties connnensurate with its weight

and somewhat higher than those for oak, but it is

considered a relatively poor bending wood.

The woo<l seasons at a moderate rate with a

uioderate amount of degrade. Green lumber airdries to about 18 percent moisture content in

approximately ^ months under cover in the San

Juan area. À moderate amount of surface check-
50 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

1 inch

FIGURE .31.—Cucubano : Top, flatsawed ; bottom, quartersawed.

in«; and warping occurs during the seasoning

process.

Shrinkage is relatively uniform and not excessive for a wood of cucubano's density. Green wood

shrinks 1/4 inch (2.0 percent) per foot in width

across the growth rings and i/^ inch (4.0 percent)

per foot in Avidth parallel to the growth rings

in drying to 15 percent moisture content.

Cucubano works easily with either power or

hand tools, with generally satisfactory results in

most operations. However, the wood has a tendency to crush and crumble in boring, and it

scratches readily in sanding unless fine abrasive

paper is used. Because of its generally very

straight and uniform grain and high density, it is

also easily split by nails or screws unless properly

prebored. It takes a good polish without the use

of a filler.

Cucubano is very susceptible to dry-wood termites and probably is not durable in the ground

or when exposed to marine borers. The wood is

seldom used in Puerto Rico, but it appears to be

suitable for tool handles, fancy boxes, brush backs,

small dimension turnery parts, and other items requiring a dense, close-grained, uniform wood. It

should also be equally useful for furniture, cabinetwork, farm implements, interior trim, paneling,

and novelty items, and it may be suitable for

decorative veneer and plywood. Cucubano is

equally well fitted for exterior construction, piling

in nonteredo areas, bridgework, and other similar

uses requiring a very heavy, hard, and strong

wood.

CUPEY

Clusia rosea Jacq. (mangosteen family, Guttiferae)

Cupey is a heavy, hard, strong wood of rather

conmion appearance (fig. o'2). The heart wood is

reddish brown in contrast to tlie lighter colored

sapwood, which merges gradually into the heartwood. The wood lias medium luster, medium to

fine texture, and straight grain. Growth rings are

not e\'ident, and seasoned wood is without distinctive odor or taste. Air-dry wood weighs 52

pounds per cubic foot and green wood 72 pounds

per cubic foot at 71 percent moisture content.

The wood air-seasons at a moderate rate. Green

lumber li/g inches thick air-seasons to 17 percent

moisture content in about 6 months under cover

in the San Juan area. A moderate amount of

degrade occurs during seasoning in the form of

warp and surface checking. Surface checks are

often fairly deep, particularly around knots, and

some casehardening and collapse may also occur.

Cupey undergoes moderately liigh shrinliage

during seasoning, compared with other woods of

similar density. Green lumber shrinks at the rate

of 1/4 iiit'h (2.1 percent) per foot in width across

the growth rings and %Q inch (4.7 percent) per

foot in width parallel to the growth rings when

seasoned to 15 percent moisture content. Sapstain fungi are not troublesome during seasoning.

Cupey is moderately difficult to saw and macliine because of its great density and hardness,

yet it produces fair to good surfaces in all operations. However, some trouble is encountered in

planing and l)oring: tearing and crushing occur

frequently. The wood takes screws satisfactorily

without splitting and should glue and polish well.

Cupey is ve:-y susceptible to attack by pinhole

borers, dry-wood termites, and other inse<;ts. It is
PUERTO RICAN WOODS 51

probably poorly resistant to decay and attack by

marine borers, although specific information is not

available.

Because the wood is not particularly attractive,

it is used principally for fuel, fence posts, ancl

rural construction. However, cupey is suitable for

both light and heavy construction, cheap grades

of furniture, farm implement parts, tool handles,

and other uses requiring a heavy, strong wooil.

^nif Si!S»V":^":

1 inch

F—195339

FiGiTRE 32.—Cupey : Top, flatsawed ; hottoin, quartersawed.

ESPINO RUBIAL

Zanthoxylum martinicense (Lam.) DC. (rue family, Rutaceae)

Espino rubial, also called Martinique pricklyash, belongs to the satinwood group but lacks the

characteristic attractiveness and workability of

certain other woods in the genus. The heartwood

is creamy to light brown in color (fig. 33), sometimes with a pronounced greenish blue, and it is

not readily distinguished from the lighter colored

sapwood. Growth rings are clearly marked on

the end grain bv zones of larger and lighter colored vessels. The wood is without distinctive figure except for an inconspicuous feather pattern on

flatsawed surfaces and very fine pencil striping on

the quartersawed surfaces, both resulting from the

rmg-porous nature of the wood. The wood is

moderately hea\^ and hard, has medimii to fine

texture, straight to irregular grain, good luster,

and a rancid odor when freshly worked Air-dry

wood weighs about 35 pounds per cubic foot and

green wood 53 pounds.

The wood seasons rapidly but undergoes rather

severe degrade during the process. Green IVj^-

inch lumber air-dries to 18 percent moisture content in slightly over -t months mider cover.

Moderate amounts of bow, twist, and crook, and

very slight cup and surface checking, occur during the seasoning process.

Espino rubial undergoes moderate and uniform

shrinkage during seasoning. Green wood shrinlvs

%2 inch (1.5 percent) per foot in width across the

growth rings and i%2 inch (2.6 percent) per foot

in width along the growth rings in seasoning to

15 percent moisture content. Molds and sapstaining fungi are not particularly troublesome

during the seasoning process.

The wood works easily with either hand or

power tools but produces only fair to poor results

in most operations. Torn grain and coalise fuzziness are common in shaping and turning; tearing
52 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 205

1 inch

F—195340

FIGURE .3.3.—Espino rubial : Top, flatsawed ; bottom,

quartersawed.

and crushing are troublesome in boring and mortising; and consideral)le scratching and fuzziness

occur in sanding unless a very fine abrasive paper

is used. However, tJie wood has good resistance

to screw splitting. The best machined surfaces

are obtained when very sharp and thin cutting

edges are used along with an increased spindle

speed and a reduced rate of feed.

Espino rubial is very susceptible to dry-wood

termites, pinhole borers, and other insects. It is

not Ijelieved to be durable in contact with the

ground, although specific information as to its

vulnerability to decay is not available.

Because of its plain appearance, difficulties in

seasoning, and only fair working qualities, espino

rubial is best suited for boxes, crates, general carpentiy, low-grade furniture, light construction,

concrete foi-ms, and similar uses. However, with

considerable care in seasoning and machining, the

better grades of this species could be used for

interior trim, doors, Avindow frames, and other

types of interior construction. It might also be

suitable for utility veneer and core stock.

EUCALIPTO

Eucalyptus robusta J. E. Smith (myrtle family, Myrtaceae)

Small to occasionally medium-size logs of

eucalipto, known as swamp mahogany or swamp

messmate in its luitive Australian habitat, are

available from the extensive i)]antings of this

species in the high mountainous rain forests of

Puerto Rico. Tlie tree is also known as beakpod

eucalyptus in some areas. Logs of other Eiieitlyi>-

fm species growing on the island may occasionally

be marketed in comljination with E. rohunta, and

they liave the same general properties and uses as

that species.

The lieartAvood of eucalipto is salmon to light

reddish l)i-own when seasoned (fig. 34), ofl"en

lîiottled with brown streaks and patches, and is

indistinct from the light-brown sapwood. Faint

growth rings are evident on the end grain. The

wood is coarse in texture, quite lustrous, and fairly

straight grained, although some interlocked grain

may occur. Tlie timl>er is hard, strong, stift', and

elastic, weighing 42 pounds per cubic foot when

air-dry. Green woocl weighs 69 pounds per cubic

foot at 115 percent moisture content.

Like most other eucalypts, this wood is difficult to season. Carefully stacked ll^-inch lumber

requires about tt months to reach an air-dry moisture content of 19 percent under cover in the San

Juan area. Considerable degrade develops during

seasoning, mostly from warp, although a small

amount of surface and end checking may occur.

The wood undergoes unusually great and uneven

shrinkage during seasoning for a wood of its

density. Green wood shrinks more than % inch

(3.5 percent) per foot in width across the growth

rings and slightly over li/g inches (9.7 percent)

per foot in width parallel to the growth rings in

seasoning to an air-dry moisture content of 15

percent.
PUERTO RICAN WOODS 53

The wood works easily with both hand and

macliine tools and gives fairly good results in

most operations. There is, however, a tendency

for the wood to crush and tear in boring and for

scratches to show clearly in sanding unless fine

abrasives are used. Eucalipto ¡possesses unusual

resistance to splitting when screws are driven,

and it should take nails equally well. After appropriate fillers are used, the wood can be finished

to a smooth, satiny appearance.

The wood is considered durable in the ground,

but it is very susceptible to attack by drj^-wood

termites in Puerto Rico. On the basis of experience with other closely related species, this

wood is probably highly resistant to the penetration of preservatives.

This species is used in Australia for general construction work, especially in contact with the

ground. It should be useful in Puerto Rico for all

types of posts, utility poles, and light and heavy

construction, and for other ¡purposes requiring a

strong, durable wood. The difficulty of seasoning

sawed material and its lack of attractiveness

indicate that the wood is most usable in the round

or squared form. Yet it appears to be suitable for

flooring, boxes, crates, and cheap furniture if satisfactory methods of seasoning can be developed.

The wood is sufficiently strong and durable for

piling in nonteredo areas, but it requires the use

of caps during driving operations. Round or

squared timbers would also be very serviceable for

supports and bracing in concrete construction

Avork.

f.'ífií tí I

, mm

1 inch

F—195341

FIGURE 34.—Eucalipto : Top, flatsawed ; hottom, quartersawed.

GRANADILLO

Buchenavia capitata (Vahl) Eichl. (combretum family, Combretaceae)

Granadillo is a very attractive timber of good

quality and many potential uses. The heartwood

(fig. 35) is light yellow to golden brown and

distinct but not clearly separated from the paleyelloAv sapwood. The wood has high luster,

straight to more frequently roey grain, medium

texture, and a faint odor and mildly astringent

taste when green. Dry wood is without distinctive

odor or taste. Growth rings are marked by narrow bands of darker pores, showing as an attractive ribbon stripe on quartersawed surfaces. It is

moderately hard and strong, weighing 46 pounds

per cubic foot when air-dry and 68 pounds when

green. Air-dry granadillo weighs about the same

as white oak and is similar to it in most strength

properties.

Green lumber air-seasons rapidly with only a

very small amount of degrade in the form of

slight bow and twist. Green lumber seasons to an

air-dry moisture content of 18 percent in slightly

less than 4 months under cover in the San Juan

area.

Granadillo shrinks very little during seasoning. Green lumber loses Vs ii^fl"^ (1-1 percent) per

foot in width across the growth rings and %6 i^^'^

(2.5 percent) per foot along the growth rings in

drying to an air-dry moisture content of 15

percent.

The wood machines with moderate difficulty because of its hardness, but it produces good surfaces in all operations even though some tearing
54 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 205

may result from irregular grain. It is reported

to tinish well and to take a beautiful high satiny

polish.

The wood is rated more resistant to dry-wood

termites than Honduras mahogany or cedro

hembra and is fairly durable in the ground. Sapstain fungi or insects are not troublesome during

seasoning.

Granadillo's uniform color, attractiveness, and

good machining properties make it highly acceptable for all types of furniture and cabinetwork. It is also recommended for house framing,

flooring, construction work of all kinds, plywood,

and railway sleepers after preservative treatment.

Because of its attractiveness, it is recommended for

decorative veneer and plywood. The wood should

also be suited for interior trim, boat building,

boxes and crates of all types, turnery, and many

other uses requiring a strong, attractive wood with

good durability.

1 inch

F—195342

FiGtTRE 35.—Granadino: Top, flatsawed : bottom,

quartersawed.

GUABA

Inga vera Willd. (legume family, Leguminosae)

Gualja is a wide spreading, low branching tree

that is planted extensively for shade and protection on cotîee plantations. It i)roduces short logs

of small to medium diameter. The wood is seldom

used excei)t for charcoal and fuel, but it has sufficient strength for many other uses. Also, it is

moderately attractive (Hg. 36) and machines well.

The heartwood is pale brown to golden brown

with longitudinal streaks or patches of darker

brown that in turn are frequently shaded with

hues of green or yellow. Tlie indistinct sapwood

is wliitisli ill color. The wood is coarse in texture,

fairly lustrous, straight to frequently roey grained,

and without distinctive odor or taste. Guaba is

comparable to Douglas-tir in density, weighing 44

pounds per cubic foot when air-dry and 62 pounds

ni the green condition. Compared to woods of

similar density, guaba is considered a moderately

hard, strong, tough wood with good resistance to

splitting and good bending properties.

(xuaba air-seasons rapidly with a moderate

amount of degrade, mostly in the form of bow.

(direful piling might eliminate most of this degrade. Green lumber air-seasons to about 19 percent moisture content in 3 months under cover in

the San Juan area, undergoing moderate and uniform shrinkage during the process. Green wood

shrinks at the rate of i/g inch (1.0 percent) per foot

in width across the growth rings and ^ inch (2.0

l^ercent) per foot parallel to the growth rings in

seasoning to 15 percent moisture content.

The wood saws and machines easily and with

good results in all operations except shaping.
PUERTO RICAN WOODS 55

Torn and raised grain is particularly troublesome

in this operation.

Guaba is very susceptible to damage by termites

and other insects and to decay when in contact with

the ground. Sap-staining fungi are apt to be

troublesome in the log or freshly sawed lumber.

Because of its good strength properties, generally good machining characteristics, and moderate

attractiveness, guaba is suitable for utility furniture, boxes, crates, light construction of all types,

and general carpentry. After preservative treatment, it should also be useful for railway ties,

posts, poles, bridge timbers, and other miscellaneous exterior uses.

inch

F^95343

FIGURE S6.—Guaba: Top, flatsawed ; bottom, quartersawed.

GUAJÓN

Beilschmiedia péndula (Sw.) Benth. & Hook. f. (laurel family, Lauráceas)

The heartwood of guajón is a pinkish brown,

often with widely spaced blackish lines at irregular intervals (fig. 37), and it is readily distinguished from the pale-brown sapwood. Numerous pores are visible as fine scratches on flat

surfaces, giving the wood a somewjiat attractive

appearance. The wood has medium texture,

straight grain, medium luster, and is without distinctive odor or taste. Growth rings are not

clearly defined. Guajón is moderately hard,

strong, and heavy, weighing 41 pounds per cubic

foot when air-dry and 64 pounds when green.

The wood air-seasons slowly with only a minor

amount of warping and no visible surface checkmg. In the tests, green lumber n/g inches thick

required 10 months or longer to reach an air-dry

moisture content of 20 percent. Guajón is accordingly the slowest to air-dry but one of the least

refractory of the commercial hardwoods growing

in Puerto Rico.

Shrinkage during seasoning is moderate and

uniform. Green wood shrinks at the rate of y^

inch (2.0 percent) per foot of width across the

growth rings and %6 ii^cli (3.6 percent) per foot

along the growth rings in seasoning to 15 percent

moisture content.

Guajón" works easily, but with varying results.

It is rated "good"' in planing and shaping; "fair"

in turning, mortising, and sanding; and "poor"

in boring. Rough surfaces result from torn grain

in turning; tearing and crushing occur along the

sides of the holes in boring and mortising; and

scratches are clearly visible in sanding unless a

fine abrasive paper is used. HoAvever, surfaces

well sanded with fine abrasives are very smooth

and take a good polish. The wood has good resist-
56

'firU.S. DEPT. OF AGRICULTURE HANDBOOK NO. 205

/

ance to splitting when screws are driven and presumably will take and hold nails satisfactorily.

Guajón is very susceptible to damage by drywood termites. Although it is generally considered to be highly durable when in contact with

the ground, authentic tests proving this point are

lackmg.

The wood is used for shipbuilding, general construction, flooring, furniture, cabinetmaking, and

carpentry. It is also recommended for decorative

plywood, handles, interior trim and paneling,

agricultural implements, and other uses for which

maple and birch are used.

*;

l_

1 inch F-495344

FIGURE 37.—Guajón : Top, flatsawed ; tottam,

qiiartersawed.

GUAMA

Inga laurina (Sw.) Willd. (legume family, Leguminosae)

Guama is one of the trees planted extensively

in Puerto Rico and other Caribbean areas to shade

and protect coffee plantations. Because of its characteristic low branching and the cotïee-growers'

preference for young thrifty trees, only short,

small- to medium-size logs are available. The

wood is seldom used except for fuel and charcoal,

yet it is as attractive and serviceable as many

recognized furniture woods.

The heartwood (fig. 38) is a pale reddish brown,

often streaked with a darker brown, and not clearly

distinguished from tlie lighter colored sapwood.

Luster is medium to high, and the texture is coarse.

The grain is straight to more frequently roey.

showing as ribbon stripes on flatsawed surface's!

Odor and taste are lacking in seasoned wood. The

wood is medium in density, weighing 46 pounds

when-iu)--dry as cominired with 48 pounds for

white oak and 44 pounds for sugar maple. Green

wood weighs 67 pounds per cubic foot. It is moderately hard, strong, and tough, comparing favorably in strength properties with other woods of

similar density.

Guama seasons rapidly with moderate degrade

in the form of very slight twist and crook and moderate bow. Green lumber air-seasons to about 18

percent moisture content in approximately 4

months under cover in the San Juan area. The

wood undergoes low and uniform shrinkage during seasoning and is stable after manufacture.

Green wood shrinks at the rate of about % inch

(1.6 percent) per foot in width across the growth

rings and y^ inch (2.7 percent) per foot in width

parallel to the growth rings in seasoning to 15

percent moisture content.
PUERTO RICAN WOODS 57

The wood Avorks easily and with generally good

results except that some torn grain occurs in

pieces Avith roey grain, particularly in planing and

shaping, wliere only fair results are obtained.

The wood finishes satisfactorily and takes lacquer,

varnish, or paint veiy well after a grain filler is

applied. It also has good resistance to screw

splitting, and it glues satisfactorily but is somewhat difficult to nail unless prebored.

Guama is very susceptible to termite damage and

decay. Logs are also quickly attacked by pinhole

borers if not converted into lumber soon after

felling. Sap-staining fungi are not troublesome

in either the logs or green lumber.

Guama is suitable for many of the same purposes as oak, such as furniture, cabinetwork, tool

handles, interior trim, general construction, crates,

boxes, and flooring. After treatment with preservatives, it should be useful for posts, railway

crossties, bridge timbers, and other exterior work.

It has also been recommended for both decorative

and utility-grade veneer and plywood.

1 -n1 . " ^

•J.. .V.

mm Mk

( * • -

il|. ÍI

: to"'' i'

1 inch

F—195345

FIGURE 38.—Guama : Top, flatsawed ; hottom,

quartersawed.

GUANO (BALSA)

Ochroma pyramidale (Cav.) Urban (bombax family, Bombacaceae)

Guano, also called balsa, is the lightest commercial wood used today. Good-quality lightweight wood of this species is increasingly more

difficult to obtain and correspondingly higher in

cost as the Central American supply is depleted.

Unfortunately the wood growing in Puerto Eico

is generally somewhat heavier than the export

grade accepted by importers; it is somewhat less

buoyant and not so efficient for insulation against

heat and sound as the export grade.

The heartwood is pale brown or slightly tinged

with red. The sapwood, which provides most of

the commercial wood, is nearly white or oatmeal

colored, often with a yellowish or pinkish hue.

The grain is very coarse (fig. 39), straight, and

uniform. The wood is odorless, tasteless, and has

a rather high, silky luster and velvety feel. In the

tests, wood from trees grown in Puerto Rico averaged 17 pounds per cubic foot when air-dry and

27 pounds when green as compared with 27 pounds

for air-dry western white pine of the United

States. The commercial grade of guano used by

industry weighs 8 to l-t pounds, with an average

of about K) pounds i^er cubic foot.

The Puerto Eican guano air-seasoned at a

moderate rate when closely piled, reaching a moisture content of about 17 percent in 5 to 6 months

under cover in the San Juan area. Moderate degrade occurs during seasoning in the form of

slight to moderate cup, slight bow and twist, and

a very slight amount of crook, surface checking,

and end checking. Casehardening was not evident

in the study.

The wood is reported to air-season satisfactorily

by end-racking in Ecuador where 4:V2"ii^cli thick

stock seasons below 20 percent moisture content

in 14 to 21 days. Guano is reported to be somewhat difficult to kiln-dry; is has a tendency to

split, warp, and caseharden ; and to be practically

toasted, in the kiln-drying i^rocess.

ixuano undergoes considerable shrinkage during

seasoning for a wood of its density ; afterwards it

loses or gains moisture quickly with changes in
58 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 205

FIGURE 39.—Guano

1 inch

(bal-sa) : Top,

quartersawed.

flatsawed ;

r—495346

hottom.

atmospheric conditions, but fortunately undergoes

relatively small dimensional changes. Waterpi-oofing treatments with paraffin, commercial

water repellents, varnish, or glossy paint are eiïective in reducing the hygroscopicity of the ^YOod.

The ratio of tangential to radial shrinkage is high,

indicating that considerable stress may occur

during seasoning, leading to the development of

seasonina' defects. Green wood shrinks at the rate

of l^ inch (1.3 percent) per foot in width across

the growth rings and %6 iri^h (4.7 percent) per

foot in width parallel to the growth rings in seasoning to 15 percent moisture content. The longitudinal shrinkage of 0.11 percent is also moderately high for wood of guano's low density.

Guano is easy to work with sharp, thm-edged

power or liand tools, with practically no dullhig

effect on cutting edges. Thin-gage saws are recommended because thick-edged tools produce wooly

surfaces and cause the wood to crumble, particularly in planing. In most machining operations

the wood is fairly difficult to work wàthout the occurrence of fuzziness and cnmibling. Guano takes

nails and screws readily but is too soft to hold them.

Inasmuch as the wood glues satisfactorily, this

is tlie most satisfactory method of fastening or

holding it in place. Guano can be stained satisfactorily and polished fairly well, but it absorbs

much of the material during the process. The use

of a filler is necessary if a good surface coating is

desired.

Termites, marine borers, and decay organisms

readily attack the wood and cause severe damage.

Despite its softness and porosity, guano is fairly

resistant to impregnation with preservatives, although both heartwood and sapwood can be

satisfactorily treated by either pressure or nonpressure methods. However, pressure treatment

often causes collapse of the cell walls.

The strength of guano varies directly with its

density. In general, the wood is stronger for its

weight than other timbers. The slow-growing

and consequently heavier grade of guano growing

in Puerto Rico is suitable for certain types of

fruit and vegetable containers, novelties, toys, and

temporary boarding or cement forms. Material

treated against termite attack should also be adeqiu\te for cores of flush doors and other light const ruction. In general, guano can be used for many

puri)oses for which the heavier grades of commercial balsa are commonly acceptable, and as a

substitute for white pine where high strength and

stability are not essential.

GUARAGUAO

Guarea trichilioides L. (mahogany family, Meliaceae)

ixuaraguao, also called American muskwood, is

frequently ])la)ited for shade and protection in

cortee plantations, pi'odncing short logs of medium

to large dianietei'. The very attractive heartwood

(fig. 40) is pinkish to red when first cut, turning

and exsai)wood is

distinrt hut not clearly demarcated from the heart-

« (jud. The luster is rather low. texti.uv is

medium, ;iii([ o-rain is straiglit. ÍTreen vrood is

a. light reddish brown

¡xj'-iiri'. The whitish to

lifter seasoning

brownish

aromatic, but no distinctive odor or taste is evident in sea.soned wood. It is a moderately heavy

wood, weighing 38 pounds per cubic foot air-dry

and 71 pounds green. Guaraguao is strong and

tough for its weight in comparison with other

woods of similar densit_y.

Lumber of this species seasons slowly, requiring

about 8 months under cover in the San Juan area

to air-season IVg-inch material to 19 percent

moisture content. Seasoning is accompanied by
PUERTO RICAN WOODS 59

a moderate amount of warping, and sap\Yood

pieces tend to distort more than heartwood pieces.

No surface checking was evident in tlie tests.

The wood undergoes moderately and fairly

uniform shrinkage during seasoning. Green

wood shrinks y^ inch (1.4 percent) per foot in

width across the growth rings and y^g iiich (3.7

percent) per foot in width parallel to tlie growth

rings in seasoning to 15 percent moisture content.

The wood is reputed to be stable after manufacture.

Guaraguao saws and machines easily and well

in all operations except boring. In this operation

it has a tendency to tear and crumble. Silica is

present in the wood but has no detrimental effects

on its machining properties. The wood takes a

high lustrous finish with eitlier varnish or

lacquer.

Guaraguao has good resistance to dry-wood

termites and is durable in the ground. The heartwood is considerably more resistant to dry-wood

termites than Honduras (Mexican) mahogany but

rates somewhat below West Indies mahogany in

this characteristic. The heartwood is highly resistant to impregnation with preservatives but the

sapwood responds well to pressure treatment.

Because of its attractiveness, good strength,

durability, and favorable working properties,

guaraguao is well suited for furniture and cabinetwork, tumeiy, interior trim, and general construction and carpentry. Guaraguao has strength and

working properties similar to those of white oak

and is suitable for most of the same purposes.

For veneer, the wood may be similar to other related species that are suitable but require considerable steaming for either rotaiy or slicing

operations.

1 i'v

' ' .'' * '.

:í

'l I » , flu

i\ ,'

j

1 inch

F—495347

FIGURE 40.—Guaraguao : Top, flatsawed ; hottom, quartersawed.

GUAYABOTA

Eugenia stahlii (Kiaersk.) Krug & Urban (myrtle family, Myrtaceae)

Guayabota is an attractive grayish-brown wood

M'ith a very mild and pleasant scent but without

distinctive taste. Growth rings are marked by

narrow bands of darker colored wood (fig. 41),

which shows on the quartersawed surface as closely

spaced, darker colored lines. The pinkish-brown

sapwood is clearly distinct from the heartwood.

The wood has fine texture, irregular grain, and

medium to low luster. It is very hard, heavy,

tough, and strong, weighing .57 pounds per cubic

foot air-dry and 72 pounds green.

The wood is moderately difficult to season.

Green lumber air-dries at a moderate rate, reaching 18 to 19 percent moisture content in 5 to fi

months under cover in the San Juan area. A moderate amount of warping and a small amount of

surface checkmg occur during seasoning.

High but uniform shrinkage occurs during seasoning. Green wood shrinks at the rate of 1/3 inch

(2.8 percent) per foot in width across the growth

rings and % inch (5.8 percent) per foot in width

parallel to the growth rings in seasoning to 15

percent moisture content. However, its longitudinal shrinkage of 0.06 percent is low for a wood

with irregular grain.

Guayabota is moderately difficult to work because of its hardness, but it machines to a very

smooth sui'face in all operations except sanding.

The wood is rated "poor" in sanding on the basis

that scratches show clearly unless very fine abrasi\-e paper is used. Yet a glossy-smooth surface

can be obtained when 4/0 or 5/0 grit paper is used.

Guayabota is extremely susceptible to screw splitting, rating lowest of the woods tested. Preboring
60 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

1 inch

FiGUHE 41.—Guayabota : Top, flatsawed ;

bottom, quartersawed.

proper size lead holes for screws or nails is very

essential in this wood. The smooth surfaces obtained in machining should finish and polish

satisfactorily.

Guayabota is very susceptible to dry-wood termites and is reported to be variable in decay resistance, with the darker colored specimens being

the most durable.

This wood is suitable for furniture, cabinetwork,

turnery, carving, interior trim, tool handles, agricultural implements, boat building, and both light

and heavy construction. Quartersawed material

is the most attractive and should be used where appearance is important. After proper preservative

treatment, guayabota would be acceptable for

posts, poles, piling, and other exterior uses above

and below ground.

HIGÜERILLO

Vitex divaricata Sw. (verbena family, Verbenaceae)

Higiierillo, or white fiddlewood. is closely related to teca and possesses many of the good features of that wood. The heart wood (fig. 42) is

tan to brown colored wlien freslily cut and generally variegated witli darker shades of tan or

brown. After seasoning and exi)osure, the heartwood l)ecomes gray brown to deep brown, often

with indistinct alternating narrow bands of

lighter or darker wood. Tlie fairly distinct SR\)-

wood is grayisli colored when green, turning a

light brown upon diying.

The wood has medium luster, fine texture, and

fairly well defined growth layers. Tlie grain is

irregular and interlocked, making it unusually

strong in resistance to splitting. Odor and taste

ai'e not distinctive in seasoned wood. Higiierillo

is a lieavy wood, weighing 47 pounds per rul.)ic

foot aii-diy and 7'2 pounds green.

Green lumber dries so slowly that it is impractical to air-season the Avood on a commercial scale.

In the study, higiierillo was not completely airdry after more than 1 year under cover in the

San Juan area. Degrade, which occurred during

the 1-year seasoning period, was confined to a

small amount of warping; there was no apparent

surface checking, end splitting, or casehardening.

Higiierillo undergoes moderately low and uniform shrinkage for a wood of its high density,

being considerably better in this respect than

manv other woods of similar weight. Green wood

shrinks at the rate of %6 "i^cli (1.6 percent) per

foot in width across the gi-owth rings and Vie

inch (3.5 percent) per foot parallel to the growth

rings in seasoning to 15 percent moisture content.

Its longitudinal shrinkage of 0.21 percent is nominal for a wood with interlocked grain.
PUERTO RICAN WOODS 61

Higüerillo sa^vs and machines easily with fairly

good results. It is an excellent wood to turn but

planes poorly because of the tearing and roughness

that develop in the numerous pieces having irregular grain. The wood gives good results in

shaping, boring, and mortising, but fine abrasives

are necessary in sanding to obtain good results.

It finishes satisfactorily and takes a high polish

but, judging by related species, it may be somewhat

difficult to glue.

The wood is moderately resistant to dry-wood

termites. Although specific information is lacking for higüerillo, closely related species are reported to have some resistance to marine borers

and fair resistance to fungal attack. Higüerillo

is a strong, hard, tough wood, comparable to white

oak in all strength properties.

A closely related species, Vitex gaumeri, of British Honduras, has been used successfully for polostick heads because of its high resistance to

splitting and denting. Higüerillo may be equally

useful for this purpose and for other purposes

such as golf-club heads, croquet mallets, other

sporting goods, and tool handles. It should also

be suitable for boat decking and planking, flooring, and general construction. In Central America, several other species of Vitex are used for

heavy and durable construction. 1 inch ^^^3,^

FiGUKE 42.—Higüerillo: Top, flatsawed ; bottom, quartersawed.

JACANA

Pouteria multiflora (A. DC.) Eyma (sapodilla family, Sapotaceae)

The heartwood (fig. 43) of j ácana is reddish

brown and not readily distinguished from the dull,

light-brown sapwoocl. The wood has uniformly

fine texture, generally straight grain, and medimn

to low luster. Growth rings are not evident, and

odor and taste are absent in seasoned wood. It is

very hard, firm, strong, and very heavy, weighing

59 pounds per cubic foot air-dry and 74 pounds

green.

Jácana is a difficult wood to air-season ; it dries

slowly, with considerable degrade. About 7

months is required to air-season the wood to 17

percent moisture content under cover in the San

Juan area. Moderate cup, bow, twist and surface

checking occur during the seasoning process, along

with very slight crook and slight end checking.

Surface checks and end splits are apt to be deep

whenever they occur and to widen and extend as

drying progresses. None of the defects is par596033 0—61 5

ticularly serious individually, but in the aggregate

they cause a considerable loss during seasoning.

High but uniform shrinkage occurs during seasoning. Green wood loses %6 inch (3.6 percent)

per foot in width across the growth rings and %

inch (5.4 percent) per foot along the growth rings

in drying to 15 percent moisture content.

The wood is fairly difficult to work because of

its high density, hardness, and silica. Yet it is

considered a good working wood except in i)laning. Considerable torn grain occurs in this operation when wavy or irregular grain is present and

to some extent in straight-gi'ained pieces. Because of its high density and straight, even grain,

the wood splits rather easily with screws or nails

but should finish and glue satisfactorily.

Jácana is moderately resistant to dry-wood termites and other insects, and it probably is slightly

to moderately resistant to decay when in contact
62 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

1

ü-íf*

1 inch

FIGURE 43.—.Tacana : Top, flatsawed : bottom

sawed.

F-495350

, quarterwitli the ground. Molds and sap-staining fungi

are not troublesome in the log or during seasoning.

The difficulty in seasoning jácana, plus its common appearance and only fair planing qualities, restricts its use to some extent. It is currently used

in other Caribbean areas for heavy construction,

house framing, bridgework, posts, and other uses

requiring a lieavy, hard, strong wood. It sliould

also be suitable for furniture, agricultural implements, some types of sporting goods, heavy flooring, piling in nonteredo areas, and boat timbers.

JAGUA

Genipa americana L. (madder family, Rubiaceae)

Jagua, or genipa, is an attractive timber suitable for many of the same uses as ash, maple, and

birch. The heartwood (fig. 44) is a very light

yello-vvish brown, occasionally with a slight pinkish- or purplish-blue overcast, merging gradually

into the cream-colored sapwood. Growth rings

are indistinctly marked by narrow bands of darker

colored wood which at times show on the quartersawed surface as faint lines, giving the wood an

attractive striped figure. Flatsawed surfaces frequently have a ribbon stripe.

The wood lias medium luster, ratlier fine texture,

and straight to irregular grain. Distinctive odor

and taste are not ap]:)arent in seasoned wood. The

wood is hard, heavy, strong, and resilient, weighing r>l ])ounds when nir-dry and ()4 ])ounds green.

Jagua air-seasons slowly, green fi^-inch lumber

requiring 7 to 8 months to reach 20 percent moisture content. However, only a minor amount

of warping occurs during seasoning, and virtually

no surface checking.

The wood undergoes moderate and fairly uniform shrinkage during seasoning and should stay

in place well after manufacture. Green wood

shrinks at the rate of about Vs inch (l.Y percent)

per foot in width across the growth rings and 1/2

inch (4.1 percent) per foot parallel to the growth

rings in drying to 15 percent moisture content.

Jagua works easily and with excellent results,

machining better than most other Puerto Rican

woods, and ranking well above mahogany, teca,

and other well-liked cabinetwoods. It has good

resistance to screw splitting, glues satisfactorily.
PUERTO RICAN WOODS 63

and should take all types of stains and finishes

without difficulty. The heartwood is very susceptible to pinhole borers, dry-wood termites, and

decay. Sap-staining fungi are seldom troublesome during seasoning.

Jagua is used for shoe lasts, plow beams, tool

handles, barrel hoops, chests, and many other

products requiring fine and uniform texture combined with high strength and resilience. The

wood is especially good for all types of bent work

and should be a very satisfactory substitute for

ash. Its excellent machining qualities, attractiveness, and uniform texture make it an excellent

material for furniture, cabinetwork, and turnery

of all types. It should also work well as flooring,

interior trim, and decorative veneer, and for most

purposes for which maple, birch, or ash are cur

rently preferred.

1 inch

F—195351

FIGURE 44.—Jagiia : Tot), flatsawed ; 'bottom,

quartersawed.

JAGÜEY BLANCO

Ficus laevigata Vahl (mulberry family, Moraceae)

This species is related to the common cultivated

fig. Ficus caHca L., and the rubber plant of the

florists, F. eJaaticd Roxb., from the Far East. The

tree and wood are known in Puerto Rico as jagüey

blanco. The English name is shortleaf fig. The

tree does not produce edible fruit.

Both the heartwood (fig. 45) and sapwood are

a uniform light brown. The wood is composed of

alternating bands of wood fibers and soft parenchyma, which shows on the flatsawed surface as

an irregular darker brown pattern and on the quartersawed surface as a very fine, closely spaced

striping. Surfaces having an appreciable amount

of the soft, darker colored parenchyma tissue are

correspondingly more difficult to machine.

The wood has low luster, coarse texture, and

straight gram. It is fairly light and soft, but

tough and strong for its weight. Air-dry wood

weighs 30 pounds per cubic foot and green wood

about 55 pounds.

The wood is heavily saturated with moisture

(119 percent) when first cut. It seasons slowly,

requiring 6 to 7 months to reach an air-dry moisture content of 17 percent in the San Juan area.

However, very little degrade occurs and even the

widest boards dry with a minimum of distortion.

Degrade is confined to slight bow and twist and

very slight cup and crook. Discoloration of the

sapwood by fungi is common during the early

stages of seasoning, and it is difficult to control

unless the lumber is immersed or sprayed with a

fungicide solution immediately after sawing.

Shrinkage is low and fairly uniform during seasoning. Green wood shrinks at the rate of i/g inch

(1.0 percent) per foot in width across the growth

rings and 1/3 inch (2.8 percent) per foot along the

growth rings in drying to 15 percent moisture

content.
64 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

1 inch

FIGURE 45.—.Jafíüey blanco ; Top, flatsawed

quartersawetl.

r-4953r)2

bottom,

Jagüey blanco works easily but with poor results, except in planing and sanding, in which

satisfactory surfaces are obtained. The wood

tends to pickup and fuzz in shaping and turning

and to crush and crumble in boring and mortising.

The preponderance of soft parenchyma tissue is

responsible for most of the machining difficulties.

It is also responsible for all surfaces being somewhat rough to the touch and requiring careful

sanding before polishing. Jagüey blanco has excellent resistance to screw splitting, and it is reported to take and hold nails firmly and finish

smoothly with paint or varnish.

The wood is very susceptible to damage by termites and other insects, decay-causing fmigi, and

probably marine borers. But, judged by its appearance and structure, jagüey blanco should be

easily impregnated with preservatives to combat

these destructive agencies.

The various Ficu^ woods are generally considered to have limited commercial value on the

export market, though they are suitable for many

everyday purposes if seasoned before they can decay. Air-dry jagüey blanco can be used for boxes,

crates, interior construction, general light carpentry, and temporary concrete forms. After proper

preservative treatment, it would also be suitable

for numerous outdoor uses wliere a light, easily

nailed, moderately strong wood is acceptable.

JOBO

Spondias mombin L. (cashew family, Anacardiaceae)

Jobo, or yellow luomhin, is a soft, lightweight

wood of common appearance ( fig. 4fi ). When first

cut, the heartwood is but!' colored and indistinguishable fi'oni the sapwowl, hut when seasoned it

turns a golden hrown and is readily distinguished

from the cream-colored sapwood. Hoth lieart wood

and sai)wood are often turned to a hUie-gray color

hy sap-staining fungi during the early stages of

seasoning. Jobo weighs about .'50 pounds when

air-diy aiul (iO pounds when green at VoZ percent

moisture content.

The wood has straight to slightly interlocked

grain and coarse texture. Numerous pores, barely

visible on end surfaces, appear on the longitudinal

surfaces as distinct gi-ooves or as somewhat darker

lines or scrntclies against llie ligliler background.

The vvoíKÍ ])ossfsses no cliuractei-ist ic odor oi' taste.

Jobo is moderately easy to season. Green wood

li/s inches thick air-dries to a moisture content of

about If) percent in 6 months under cover in the

San Juan area. Moderate degrade occurs during

seasoning in the form of very slight cup, moderate

bow, slight twist and crook, and very slight end

and surface checking. Heavy mold occurs on both

sapwood and heartwood unless the wood is immersed in a fungicide soon after it is sawed.

Low and uniform shrinkage occurs duiing the

seasoning process. Green wood shrinks at the

rate of y^o inch (0.9 percent) per foot in wñdth

across the growth rings and %2 ii^ch (1.8 percent)

per foot parallel to the growth rings in drying to

a moisture content of 15 percent.

The wood is easy to work but has rather poor

machining properties unless handled carefully.
PUERTO RICAN WOODS 65

It is an excellent wood to plane but develops rough

and torn surfaces in other machining operations

that use conventional hobby-shop size machines

and tools. However, the wood sands fairly well

and has good resistance to screw splitting. Jobo

is very susceptible to decay, termites, and other

insects; logs left in the woods are soon attacked

by pinhole borers.

Jobo possesses moderate strength properties, being somewhat harder on the end and sides than

many woods of comparable density ; in general,

it is tough and strong for its weight. Jobo is used

for soft-drink cases, packing boxes of all types,

interior construction, and match splints. It has

been recommended for utility plywood. It will

produce a good yield of pulp that is suitable for

making a strong, white printing paper. With

special care in machining, the wood could also

be utilized in the cheaper grades of furniture and

cabinetwork, and it is quite suitable for light construction of all types when protected from insects

and decay. Because large cuttings take root

readily, sections of young stems and limbs of large

trees are used extensively for live fence posts.

1 inch

F-495353

FIGURE 46.—.lobo: Top, flatsawed; Jjottom, quartersawed.

JUSILLO

Calycogonium squamulosum Cogn. (melastome family, Melastomataceae)

Jusillo, also commonly known as camasey negro,

is one of several species of the genus Calycogonium that are endemic to Puerto Rico. The

pinkish-brown to pale-brown heartwood is

characterized by irregular, widely spaced black

streaks of varying widths, giving the wood an

unusual and somewhat attractive appearance (fig.

47). The sapwood is bright yellow and fairly

well distinguished from the heartwood. The

wood has fine texture, generally straight grain,

and good lustre, and it is odorless and tastless and

without distinctive growth rings. It is hard,

heavy, and strong, weighing about 56 pounds per

cubic foot when air-dry and 76 pounds when

green.

The wood seasons at a moderate rate witli a

moderate amount of degrade. Green lumber airdries to about 18 percent moisture centent in 6

months under cover in the San Juan area. Degrade is limited to a moderate amomit of warp and

some very light surface and end checking. A

small amount of casehardening may also occur at

times.

Shrinkage is moderate and uniform during

seasoning despite the wood's high density. Freshly sawed lumber shrinks i/4 inch (2.2 percent) per

foot across the growth rings and nearly 1-2 inch

(3.9 percent) per foot along the growth rings in

seasoning from the green condition to 15 percent

moisture content. Longitudinal shrinkage is also

moderate.

The wood's hardness and density make it moderately difficult to saw and machine, but it can

be worked to a glasslike surface in all operations

except planing. The frequent occurrence of torn

grain makes this operation difficult. In sanding,

the wood will show scratches unless a very fine
66 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

rrvmrwi~m'mmîm

F-49535-l

FIGURE 47.—.Tusillo: Top, flatsawed : hottom,

quartersawed.

abrasive is used. Jusillo is also very susceptible

to splitting by nails or screws unless it is prebored or adequate-sized lead holes are employed.

It should glue satisfactorily and finish exceptionally well with all types of coatings.

8 The heartwood is very susceptible to dry-wood

termites and of doubtful durability in contact

with the ground or in teredo-infested waters.

Pinhole borers will also attack the wood before

and after it is sawed.

The wood is considerably heavier, harder, and

J probably stronger than sugar maple or yellow

birch. It is suitable for the same purposes as

these woods, except where the pinkish to palebrown color or the unusual and characteristic pattern of black lines would be objectionable. The

figure is of a type that might be quite acceptable

for some purposes and quite objectionable in

otliers.

Judged by its physical properties, the wood is

suitable for furniture, pattemmaking, veneer and

plywood, agricultural implements, tool handles,

heavy-duty flooring, turnery, boat parts, and vehicle frames. It would also give good service for

heavy construction, bridge timbers, and piling in

nonteredo areas. After preservative treatment, it

should also serve well for railway ties, posts,

poles, and other products that would be in contact

with the ground.

LAUREL AMARILLO

Nectandra sintenisii Mez (laurel family, Lauraceae)

Laurel amarillo is a rather light, moderately

soft wood resembling yellow-poplar {Liriodendivn tulipifera) of the T'nited States in superficial

appearance (fig. 48). The heartwood is a pale

greenish yellow, merging gradually into a slightly

lighter colored sapwood. The luster is satiny, the

texture medium, and the grain straight to more

frequently interlocked. Odor and taste are not

distinctive in seasoned wood. Air-dry wood

weighs about 41 pounds per cubic foot and green

wood 54 pounds per cubic foot.

The wood air-seasons satisfactorily without excessive degrade. It air-dries at a moderate rate,

reaching about 17 percent moisture content in 6 to

7 months under cover in the San Juan area. Moderate degrade occurs during seasoning in the form

of very slight cup, end checking, and crook, and

slight twist and moderate bow. Surface checking

wiis not evjdpnt in the tests.

Laurel amarillo is easy to work and produces

good surfaces in all operations except planing,

where the frequent roey grain causes considerable

torn and fuzzy surfaces. The species of Nectandra^

as a group, are considered to glue and paint well

and hold nails satisfactorily. Laurel amarillo is

probably similar to other members of the genus

in these properties.

Low to moderate shrinkage occurs during seasoning. Green wood of this species shrinks at the

rate of Vs "^cli (1.1 percent) per foot across the

growth rings and i/4 inch (2.0 percent) per foot

along the growth rings in drying to 15 percent

moisture content. The wood is extremely resistant to moisture absorption and holds its place exceptionally well after manufacture.

Laurel amarillo is very susceptible to attack by

dry-wood termites, marine borers, and sap-staining

fungi. Like other closely related species, it may
PUERTO RICAN WOODS 67

be moderately durable in tlie ground. Tlie heartwood is extremely resistant to impregnation witli

preservatives, though the sapwood is easily

treated.

The wood is somewhat lighter than white oak,

but tests of other s^iecies of the genus indicate that

it should be comparable to white oak ha most

mechanical ])roperties except resistance to splitting, in which it is only 60 percent as strong as oak.

It is a moderately good bending wood.

The woocl of laurel amarillo is suitable for general construction, boxes, crates, carpentry, millwork, flooring, and interior trim. Although it is

not particularly attractive, it should be suitable

for some types of furniture and cabinetwork ; however, the wood's poor planing qualities would

necessitate considerable sanding of exposed surfaces prior to finishing. Other similar species of

Nectandra have been recommended for tool handles, instruments, crossties, and boat construction.

L

\ inch

F-495355

riGURE 48.—Laurel amarillo ; Top, flatsawed, Tjoitom,

quartersawed.

LAUREL AVISPILLO

Nectandra coriácea (Sw.) Griseb. (laurel family, Lauraceae)

Laurel avispillo, or Jamaica nectandra, has

pinkish-colored heartwood (fig. 49), which merges

gradually into light-brown sapwood. The wood

appears to have zones of tension wood composed of

soft gelatinous fibers that are similar to tlaose occurring in Mexican maliogany ; they appear as

slightly darker colored bands or stripes on flatsawecl surfaces. These areas give the wood an

attractive configuration but present trouble in

most machining operations because they develop

considerable fuzziness.

The grain is straight to irregular and tightly

interlocked, the texture is medium, and the luster

is medium to high. The wood is moderately soft

and light, weighnig 36 pounds air-dry and 51

pounds green per cubic foot.

The wood air-seasons easily and satisfactorily

except for a moderate amount of wai-ping. Surface and end checking are not troublesome. Green

lumber air-seasons to about 17 percent moisture

content in 6 months under cover in the San Juan

area. Shrinkage is moderate and uniform during

seasoning. Green wood shrinks i/g inch (1.4 percent) i)er foot across tlie growth rings and i\^^ inch

(3.3 percent) per foot parallel to the growth rings

in drying to a moisture content of IT» percent. All

species of Nectandra are reported to be stable

after manufacture.

Tlie wood is easily machined with good results

in all operations except turning and sanding.

Torn and fuzzy grain develop in turning and

severe fuzzing cluring sanding wlierever there is a
68 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

FIGURE 49.-

1 inch

F-495356

-Laurel avispillo: Top, flatsawed ; hottom,

quartersawed.

tension-wood zone. However, with extra care the

wood can be finished to a very smooth, paintable

surface and Avhen properly sanded is equal or

superior to Mexican mahogany in attractiveness.

Laurel avispillo takes and holds screws and nails

satisfactorily, glues well, and can be painted or

varnished with good results. Grain fillers are not

required as in laurel prieto.

The heartwood of laurel avispillo is v^ry susceptible to dry-wood termites and otlier insects, and

the logs are readily attacked by pinhole borers.

Both logs and green lumber are fairly resistant

to sap-staining fungi. The heartwood of other

species of Nectandra is moderately durable in the

ground but is very resistant to impregnation with

preservatives while the sapwood is not durable and

is easily treated. Laurel avispillo may have similar cliaracteristics in these respects.

The wood is suitable, with considerable care in

machining, for furniture, cabinetwork, interior

trim, paneling, toys, novelties, turning, and other

uses requiring an attractive wood of moderate

strength and durability. It is also well qualified

for general carpentry, interior and exterior construction, and possibly for decorative veneer and

plywood. The wood is also satisfactory for boxes,

crates, toys, boatbuilding, and other miscellaneous

uses.

LAUREL GEO

Ocotea leucoxylon (Sw.) Maza (laurel family, Lauraceae)

Laurel geo is a moderately soft, light wood.

The heartwood (fig. 50) is uniform light golden

brown witli medium luster, and generally it is

not sliarply delineated from the pale yellowishbrown or cream-colored sapwood. The wood has

medium texture, straight to more frequently interlocked grain, and lacks distinctive odor or taste

when seasoned. The lack of figure and the wood's

dull-brown color give it a rather common appearance. Air-dry wood M'eighs ^U pounds per

cubic foot and green wood 5f) pounds per cubic

foot.

Laurel geo is difficult to air-season. The wood

dries at a moderate rate, reaching an air-dry

moisture content of Ifi percent in about 5 months

under cover in the San Juan area. There is severe

degrade during aii'-seasoning in tlie form of cup,

liOAv, twist, and crook, Imt no ai>i)ivciable end or

surface clieckinu'.

Moderate and uniform shrinkage occurs during

air-drying. Green wood shrinks %2 ii^^h (L2

percent) per foot in width across the growth rings

and % inch (2.4 percent) per foot along the

growth rings in drying to an air-dry moisture

content of 15 percent. As judged from tests of

other s])ecies of Ocotea. laurel geo should be stable

after manufacture and should withstand exposure

well without the protection of paint.

Laurel geo saws and machines easily with little

dulling eft'ect on cutting edges. Machined surfaces are acceptably smooth, except for a tendency

toward fuzziness in sanding and frequent crushing

and tearing of the wood in boring. Other similar

species of Ocotea are known to take good finish

with ])aint, stain, or varnish, to glue well, and to

hold nails satisfactorily except on the end grain.
PUERTO RICAN WOODS 69

The wood is moderately resistant to dry-wood

termites, and observation of closely related species

indicates that it may be moderately resistant to

decay. The heartwood of other species is highly

resistant to impregnation with preservatives while

the sapwood is easily treated. Sap-staining fungi

are troublesome in freshly cut logs and lumter, and

pinhole borers often attack logs soon after felling.

Laurel geo is suitable for inexpensive grades of

furniture and cabinetwork and for interior trim,

general capentry, and light interior and exterior

construction. It may be one of the better local

woods for boxes and crates, plywood, sheathing,

concrete forms, and other products where a

moderately light, easily worked, yet moderately

strong wood is required. It does not possess sufficient attractiveness for decorative purposes to

compete with a number of other local woods.

1 inch

F-49Ó35T

FIGURE 50.—Laurel geo : Top, flatsawed ; hottom,

quartersawed.

LAUREL PRIETO

Nectandra membranácea (Sw.) Griseb. (laurel family, Lauraceae)

Laurel prieto logs are generally small in

diameter but of good quality. The heartwood is

yellowish brown to golden brown in contrast to the

fairly distinct grayish-colored sapwood. The

wood lacks attractive figure except for the presence of faint ribbonlike stripes (fig. 51) in those

pieces having fairly distinct growth rings. Open

pores on the encl grain appear as elongated

scratches on flatsawed surfaces, giving the wood

a somewhat rough texture. The wood has straight

to occasionally wavy grain, medium texture, and

medium luster. Air-dry wood weighs 84 pounds

per cubic foot and green wood 46 pounds per cubic

foot.

This timber air-seasons at a moderate rate and

satisfactorily, reaching an air-dry moisture content of about 16 percent in 6 months under cover

in the San Juan area. A minor amount of degrade occurs in the form of slight bow and very

slight cup, twist, and crook. Surface checking

and casehardening are not a problem.

Shrinkage is moderate and uniform during

seasoning. amouiUing to %2 ii^t'h (1.3 percent) per

foot in width across the growth rings and i%2

inch (o.O percent) per foot parallel to the growth

rings from green to an air-diy moisture content

of 15 percent. Seasoned wood holds its place well

after manufacture.

Laurel prieto saws and machines easily, but it

has a tenctency to tear and develop fuzziness during sawing. Good results are obtained in planing,

shaping, and mortising ; torn grain is quite troublesome in tuniing and boring ; and fine scratches are

evident in sancting. If fine abrasives are used, the
70 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 205

'V .\r

'4

V

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wood can be finished to a smooth, uniform

surface. The wood takes all types of finishes satisfactorily after its characteristic open grain has

been properly filled. It should nail and glue without difficulty.

The heartwood of laurel prieto is considered

very susceptible to dry-wood termites and may

be vulnerable to decay-causing organisms. Logs

and lumber are both subject to sap-staining fungi.

The heartwood of other species of Nectandra is

reported to be very resistant to impregnation with

preservatives. This species may be similarly resistant.

Laurel prieto's wood is moderately soft and

light but, if similar to other closely related species,

should possess good strength properties. It lacks

attractiveness and good working properties for

use in furniture and cabinetwork, but it is suitable for boxes, crates, interior trim, and possibly

plywood. The wood is sufficiently stron,g for general carpentry and light construction of all types,

particularly for studding, sheathing, wall partitions, and similar iises.

1 inch

F-495358

FiGUKf; ~i\.—Laurel prieto : Top, flatsawed ; bottom,

qiiartersawed.

LAUREL SABINO

Magnolia splendens Urban (magnolia family, Magnoliaceae)

Laurel sabino is limited to Puerto Rico, where

it is one of the most highly regarded woods for

furniture and cabinetwork Short logs of medium

to frequently large diameter are obtained from

the very old ci-ooked-growing trees found scattered in the higli rain forests of the eastern

mountains.

Freshly cut heartwood (fig. 52) is an unusual

and very attractive olive green, turning medium

to dark brown upon seasoning and exposure.

Growth I'ings are marked by fairly distinct lines

of lighter coloi-ed wood wliich appear on the

quartersawed surfaces as longitudinal stripes and

on ñatsawed surfaces as wavy lines, giving the

wood a very attractive figure. Frequent dark

streaks give the wood additional figuration. The

s:ii)Vii)o,l is wliilish wlien freslily i-iit, liecoming

somcw'iKit duri<cr upon seasoning and exposure.

The grain is straight to more frequently wavy,

texture is fine and uniform, and odor and taste are

not evident. The wood is moderately heavy,

weighing 44: pounds per cubic foot air-dry and

72 pounds green.

This wood is easy to air-season, drying rapidly

with only minor degrade in the fonii of very

slight bow and slight twist. Other fonns of warp

and surface checkhig were not apparent in the

Puerto Rican tests. Green lumber IVg inches

thick air-seasons to about 17 percent moisture

content in ?> to 4 months under cover in the San

Juan area.

Shrinkage is mcKlerate in all directions and

somewhat below that of other woods of similar

density. Green wood shrinks at the rate of Yie

inch (1.5 percent) per foot in width across the
PUERTO RICAN WOODS 71

growth rings and s/ig inch (2.6 percent) per foot

along the growth rings in drying to 15 percent

moisture content. Molds and sap-staining fungi

seldom develop during seasoning. The wood stays

in place well after manufacture.

Laurel sabino saws and machines easily. However, in planning, considerable tearing occurs as

a result of the irregular grain. In the Puerto

Rican tests, the wood gave fair results in planing;

good resiüts in shaping, turning, boring, mortising, and screw splitting; and fair results in sanding. A fine abrasive paper should be used to overcome scatching. The wood is moderately resistant

to dr}^-wood termites but very susceptible to decay

when in contact with the gi'ound.

Laurel sabino is moderately strong, comparing

favorably with other woods of similar density.

It is used extensively in Puerto Rico for furniture and cabinetwork. The wood has a number

of desirable qualities and should be suitable for

utility and decorative veneer and plywood, millwork, turnings of many types, durable construction, boat planking, and general interior and exterior construction and carpentry. LTnfortunately, the exceptionally attractive bright

olive-green color in freshly worked wood disappears through an oxidation process that leaves

the wood a pleasing but less attractive brown.

mm !

1 inch

F—195359

FIGURE .52.—Laurel sabiuo ; Top, flatsawed ; bottom;

quartersawed.

MAGO

Hernandia sonora L. (hernandia family, Hernandiaceae)

Mago is a firm, soft, lightweight wood resembling the heavist grades of guano (balsa). The

heartwood (fig. 53) and sapwood are indistinguishable, both grayish white in color with

occasional faint olive-colored streaks. Numerous

large darker colored pores are visible on the end

grain and appear on longitudinal surfaces as

numerous brown dots or scratches, giving the

wood a characteristic but not particularly attractive appearance. The wood has low luster,

medium to coarse texture, and straight grain.

Air-dry wood weighs about 21 pounds per cubic

foot and green wood 35 pomids per cubic foot

as compared with 9 to 12 pounds for the commerical grade of air-dry guano.

The wood air-seasons satisfactorily. It dries

at a rapid rate with only minor degrade in the

form of very slight cup and crook, slight bow and

twist, and without any apparent surface or end

cliecking. Green IVs-incb lumber air-seasons to

about 17 percent moisture content in slightly over

4 months under cover in the San Juan area.

Shrinkage is moderate and uniform. Green

wood shrinks i^e i^'^'^'li (l-'i percent) per foot in

width across the growth rings and %2 inch (2.4

percent) per foot parallel to the growth rings

in drying to an air-dry moisture content of 15

percent.

Mago works easily with eitlier hand or power

tools but develops fuzziness in most operations

and is reported to dull saws and knives rather

quickly. Tlie use of very sharp and thin cutting

edges is recommended. Mago is rated poor to

very poor in all machining qualities but, because

of its softness and straight grain, takes both nails

and screws without splitting. Finishing and

polishing is difficult ; this is due to the soft, porous

nature of the wood.
72 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 205

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1 inch

F—195360

FIGURE 53.—Mago : Top, flatsawed ; 'bottom, quartersawed.

Mago is very susceptible to termites and other

insects, marine borers, and decay-producing

organisms. It probably is penetrated readily by

preservatives and could be made acceptable for

many uses by preservative treatment.

Because of its light weight, softness, and low

strengtli properties, mago is restricted to such

uses as light boxes, crates, fishing floats, temporary

boarding, and interior construction. It has been

recommended for utility plywood and could be

used as a substitute for the heavier grades of

guano (balsa). The wood is also used in British

Guiana for flooring and native canoes in addition

to most of tlie above uses.

MAMEY

Mammea americana L. (mangosteen family, Guttiferae)

Mamey wood is obtained from trees better

Ivnowii for their fruit, the mammee apple, than

for their wood. The wood is not plentiful and

is very difficult to season, ))ut it is quite attractive

and works very well.

Seasoned heartwood (fig. 54) is a reddish

brown, merging gradually into the dull, slightly

lighter colored sapwood. The surface of both

heartwood and sapwood are often flecked with

small, dark-colored oily exudations. The grain

is straight to more frequently irregular and interlocked, and the texture and luster are medium.

Odor and taste are not distinctive in seasoned

wood. Mamey wood is hard, heavy, and strong,

weighing 54- pounds })er cnlnc foot air-dry and

71 poinuls green.

Tlie wood is difficult to season, requiring about

5 mouths to air-dry to ±2 percent moistui-e content

and undergoing considerable degrade during the

process. Severe cup, twist, and surface checking,

and moderate bow, crook, and end checking

develop during seasoning. Moderate to severe

collapse and casehardening were also noted in the

Puerto Rican study in which at least 50 percent

of the volume was lost through seasoning defects.

Mamey undergoes exceptionally high shrinkage during seasoning and is quite unstable after

manufacture. Green wood shrinks %_ inch (5.4

percent) per foot in width across the growth rings

and nearly IV2 inches (12.1 percent) per foot

parallel to the growth rings in drying to 15 percent moisture content. A longitudinal shrinkage

of 0.08 percent is also high for the wood's density,

usually indicating unfavorable seasoning characteristics.
PUERTO RICAN WOODS 73

Mamey is moderately easy to saw and machine

and produces satisfactory results in most operations. The wood gives some trouble in sanding,

because of the small scratches that occur when

ordinary sanding belts are used. A sanding grit

of A/O grade or finer is required to obtaiii scratchfree surfaces. The numerous small "resin" ducts

may also cause trouble when certain types of

finishes are desii'ed. For a wood of its density,

mamey is unusually resistant to splitting by screws

or nails. It is very susceptible to damage by drywood termites but is moderately durax)le in the

ground.

Because of its poor seasoning characteristics,

heavy shrinkage, and lack of stability after manufacture, mamey is not suitable for furniture and

similar uses. It is used principally for fence

posts, fuel, and miscellaneous domestic purposes.

But it may be useful for turning and novelty items

in which its attractive and somewhat unusual appearance would be of value. The wood could also

be utilized for some types of general construction

and carpentry.

> '

F—195361

FIGURE 54.—Mamey: Top, flatsawed ; hottom, quartersa\Yed.

MANGO

Mangifera indica L. (cashew family, Anacardiaceae)

The mango tree is better known for its savory

fruit than for its wood, which is moderately attractive but quite difficult to work.

Seasoned heartwood (fig. 55) is a pale yellowish

color and not clearly distinct from the creamcolored sapwood. The wood is characterized by

numerous large open pores, which are readily

visible on the end grain and show as straight to

frequently wavy light-broAvn scratches on the longitudinal surfaces, givmg the wood a somewhat

stippled appearance. Growth rings are fairly

well marked by narrow bands of darker colored

wood. The wood is lustrous, medium in texture

has straight to wavy grain, and is without pronounced odor or taste after seasoning. Air-dry

wood weighs 41 pounds per cubic foot and green

wood about 59 pounds per cubic foot.

Mango is fairly easy to air-dry. The wood

seasons at a moderate rate with only minor degrade, drying to below 19 percent moisture content in about 5 montlis under cover in the San

Juan area. Green li/g-inch lumber air-dries without any appreciable surface checking and only a

minor amount of warping. Discoloration from

sap-staining fungi is not aptto occur when lumber

is stacked soon after sawing.
74 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 205

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1 inch

F—195362

FIGURE 5.5.—Mango : Top, flatsawed ; hnttom, quartersawed.

The wood undergoes fairly low and uniform

shrinkage. Green wood loses 140 i"ch (0.8 percent) per foot in width across the growth rings

and %2 inch (2.3 percent) per foot parallel to the

growth rings in seasoning to 15 percent moisture

content.

Mango works easily but with only fair results.

Torn grain and fuzziness are common in planing,

shaping, and turning. In sanding there is a tendency for scratches to show unless very fined abrasives are used. Only occasional roughness and

torn grain develop in boring and mortising.

The wood is moderately resistant to dry-wood

termites. It probably is rather low in resistance

to decay and to attack by marine borers.

Mango lacks the attractiveness and workability

for furniture and similar products, but it appears

to be well adapted for most types of construction

and other u.ses where a moderately heavy, strong

wood of low to moderate durability and fair

machining quality is acceptable.

MARÍA (SANTA MARÍA)

Calophyllum brasiliense Camb. (mangosteen family, Guttiferae)

This wood is known in Puerto Rico as both

maria and santa maria. The heartwood (fig. .56)

is variable in color, ranging from light pinkish to

recldish brown, often with fine darker colored

striping. Tlie sapwood is light brown, usually

distinct from the heartwood. Tlie grain may be

straight, but it is more frequently interlocked, the

latter type producing an attractive ribbon figure

on tlie quartersawed surface. The luster is

medium and the texture moderately coarse. The

wood is without distinctive odor and taste.

Growth rings are not evident to the naked eye.

Maria is sometimes mistaken for Honduras mahogany, being somewhat similai- in color and often

showing good figure. It is lieavier and stronger

than, maliogany and is more dui-able for some uses.

Air-dry wood weighs i?> pounds per cubic foot

and green wood (U; pounds at !)2 percent moisture

<;*Mitei)t.

Maria is very difficult to air-season. Green

lumber IVs inches thick requires 6 months or more

to reach 18 pei'cent moisture content in the San

Juan area. Seasoning is accompanied by severe

bow, twist, and crook, a moderate amount of cup,

and slight end checking. Although end checks

and splits are extended during seasoning, surface

checking was not evident in the Puerto Eican

study. Except for a tendency for moisture to remain in the center of heavy planks, quartersawed

material is reported to kiln-dry satisfactorily

when low-temperature/high-humidity kiln schedules are used.

Maria undergoes above-average shrinkage for

a wood of its density but stays in place well after

manufacture. Green wood loses % inch (3.0 percent) per foot in width across the growth rings

and %6 iiT^cli (4.6 percent) per foot along the

growth rings in seasoning to 15 pei'cent moisture
PUERTO RICAN WOODS 75

content. A longitudinal shrinkage of 0.03 percent is low for a wood having interlocked grain.

In the green condition, maria is stronger than

white oak in most strengtii j^roperties and equal or

superior to most other woods of similar density.

When air-dry, the wood is comparable to the appreciably Iieavier white oak in all strength properties except modulus of rupture, crushing

strength, hardness, and cleavage. Except for a

slight deficiency in strength parallel to the grain,

maria possesses average or better strength properties for tropical woods in its density class.

The wood is fairly easy to work and, except

for occasional dark-streaked material that contains deposits of calcium carbonate, has little dulling effect on cutting edges. The machined surfaces are generally good in shaping, mortising, and

sanding but rather rough in boring and turning.

Chipping and tearing is fairly common on surfaces with interlocked grain, especially in planing

and shaping. Cutting edges of 20° or less have

been recommended to reduce such tearing to a

minimum. Crushed and torn surfaces are also

fairly common in boring. Maria has good resistance to screw splitting. It glues, stains, and

finishes satisfactorily, requiring about the same

amount of filler as Mexican mahogany.

The heartwood is verj' susceptible to attack

by marine borers and dry-wood termites, but it

has been reported moderately resistant to subterranean termites. Generally, it is moderately durable in contact with tlie ground. The sapwood

is easily impregnated with preservatives by either

pressure or open-tank bath methods, but the heartwood is extremely resistant under pressures up to

140 poimds per square inch.

Maria is as attractive as ^Mexican mahogany and

can be used for many of the same purjjoses, but it

is considerably more difficult to season and work.

It is used for furniture, cabinetmaking, flooring,

shingles, interior construction, shipbuilding, house

framing, agricultural implements, handles, and

:¡ ^

1 inch ,_„,3,3

FIGURE •^6.—¡Maria: Top, flatsawecl : dottom.

quartersawed.

many other purposes ^^here a fairly strong,

moderately durable wood is required. It gives

fair service as railway ties and other products that

must contact the soil. The wood makes an attractive veneer, but it is seldom used for this product

because it tends to flake during tlie cutting

operation.

MARICAO

Byrsonima coriaceum (Sw.) DC. (malpighia family, Malpighiaceae)

Maricao is a moderately hard, heavy wood, resembling redgum (Liqitidmnhor Htyradfua) of

the United States in appearance and physical

properties. The heartwood (fig. .57) is reddish

brown with a purplish cast and is generally

marked by darker colored stripes, which impart a

stippled effect on the lighter colored background.

The gray to reddish-brown sapwood is distinct

from the heartwood. The luster is medium the

grain straight to slightly roey, and the texture

fine. Growth rings are not distinct. Distinctive

odor and taste are not evident in seasoned wood.

Air-dry wood weighs 48 pounds per cubic foot and

green wood 67 pounds per cubic foot.

The wood ajr-seasons fairly well, drying at a

moderate rate with moderate degrade : very slight

cup, moderate bow, and slight crook and twist.

End and surface checking are minor. Green

himber air-seasons to Ki percent in approximately

H months under cover in the San Juan area.

Shrinkage is moderate for the wood's density.

Green wood shrinks at the rate of Vie i'^^l^ (1-5
76 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

A

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1 inch

F-49Ó36Í

FIGURE .57.—Maricao : Top, flatsawed ; bottom, quarter-

.sawed.

percent) per foot across the growth rings and %6

inch (3.5 percent) per foot along the growth rings

in seasoning to 15 percent moisture content.

Maricao works fairly easily with both hand and

power tools. Good to excellent surfaces are produced in all operations. Proper size lead holes

must be prebored before screws are driven or the

wood splits ratlier badly. The wood requires

some filling before finishing.

Maricao is very susceptible to dry-wood termites and other wood-destroying insects, only

slightly resistant to decay, and fairly immune to

sap-staining fungi. However, it seems to be more

immune than most other local woods to pinhole

borers. The wood is not regarded as having any

appreciable resistance to marine borers.

Both the lieartwood and sapwood of Maricao

are recommended for fancy furniture and cabinetwork, turning, flooring, interior trim, and other

decorative uses. The wood is also suitable for

general carpentry, house framing, and heavy construction. It has been recommended for plywood

and veneer.

MASA

Tetragastris balsamifera (Sw.) Kuntze (bursera family, Burseraceae)

Masa is a high-quality wood resembling yellow

birch of the United States, and it is suitable for

the same uses. The heartwood (fig. 58) is a light

reddish brown when first cut, becoming orange

brown upon seasoning and exi)osnre. Tlie sapwood is sharj)]y demarcated, white when first cut

and later becoming a yellowish brown upon drying and exposure. The grain is irregular to very

roey, luster medium, texture uniformly fine, and

growth layers indistinct. Seasoned wood is

mildly fragi'ant but has no distinctive taste. The

wood is quite heavy, weigliing about 48 pounds per

cubic foot air-dry and 60 pounds green.

Masa is very easy to air-season, losing its moisture rapidly «ith only a very minor amount of

degrade. Green lumber fi/s inches thick seasons

to about 17 percent moisture content in less than

4 nioutl'is under cover in the San .fnati area. Degrade ocrtu-riiLu- during seasoniu"; is limited to

very slight bow and twist. Other forms of warp,

surface checking, and interior defects did not develop in the Puerto Kican tests.

Masa undergoes moderate shrinkage for a

wood of its density and should be reasonably stable

in use. Green wood shrinks at the rate of i/4 inch

(2.1 percent) per foot in width across the growth

rings and % inch (8.4 percent) per foot along the

growth rings in seasoning to 15 percent moisture

content.

The wood is moderately easy to saw and machine, producing clean, snrooth surfaces in all

operations except planing, in which considerable

tearing develops in pieces having roey grain.

Masa takes both nails and screws poorly uidess it

is properly prebored: it sands to a smooth surface,

and it is reported to polish very well with all types

of finishes.

The heartwood is very susceptible to damage

by dry-wood termites and marine borers, but it
PUERTO RICAN WOODS 77

is generally durable to very durable in contact

with the ground. The lumber is seldom discolored by mold during seasoning.

Masa is a hard, compact, tough wood with

strength properties commensurate with its high

density. It exceeds strong woods like yellow birch

and shagbark hickory (Oarya ovata) in most

strength properties, and it is exceptionally sti'ong

in resistance to splitting.

The wood lias no distinctive Hgure, but it ñnishes

much like sugar maple and yellow birch and is

suitable for manj' of the same uses as these very

popular woods. It is used for high-grade furniture, cabinetwork, paneliiig, interior construction, and oars. Other recommended uses include

millwork, light and heavy construction of all

types, house and factory flooring, and outdoor

uses where decay resistance is required.

1 inch F—195365

FiGUBE 58.—Masa : Top, flatsawed ; bottom, quartersawed.

MOCA (ANGELIN)

Andira inermis (W. Wright) H.B.K. (legume family, Leguminosae)

Moca is a hard, heavy, coarse-textured wood

that resembles palm or pitch pine {Pinu-s rígida)

in superficial appearance-. Other names for the

tree and Avood are angelin and cabbage angelin.

The heartwood (fig. 59) is yellowish brown to

dark reddish brown and clearly delineated from

the pale-brown to grayish-yellow sapwood. Soft

lighter colored tissue appears on the end grain as

wavy bands and on flatsawed surfaces as featherlike wavy bands of light-colored tissue. These

alternate bands of dark and light fibers give the

wood its unusual and decorative appearance. The

grain is straight to slightly irregular, and the

luster is rather low. Air-dry wood weighs about

47 pounds per cubic foot and green wood 74

pounds per cubic foot.

Moca air-seasons at a moderate rate without

serious degrade. Most seasoning defects occur as

596033 O—61 «

very sliglit cup and a moderate amount of bow.

Other tyj^es of seasoning- defects are slight. Green

lumber li/g inches thic-K air-seasons to about 17

percent in 5 months under cover in the .San Juan

area.

Moca undergoes low to moderate shi'inkage

during seasoning and is moderately stable after

manufacture. Green wood shrinks about VQ inch

(1.2 percent) per foot in width across the growth

rings and Vs VL\C\\ (2.5 percent) j^er foot along

the growth rings in seasoning to an air-dry

moisture content of 15 percent.

The wood works easily with both hand and

machine tools. Good to excellent surfaces are

obtained in all operations except shaping, in which

raised and torn grain are common because of the

bands of soft parenchyma tissue. A fine, ridgy

appearance—raised grain—is also likely to occur

in planing when dull knives are used. The wood
78 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 205

inch

FIGURE .59.—Moca : Top, flatsawed ;

.sawed.

hottoni,

F-495366

quartertakes nails well, glues satisfactorily, and finishes

well, but lacks lustei". Moca compares favorably

with woods of similar weight in most strength

properties except for a tendency to be somewhat

fissile. Some difficulty is encountered in French

polisliing, because the soft tissue absorbs polish

much more readily than the hard tissue.

The sapwood parts of logs and freshly cut lumber are highly susceptible to discoloration by sapstaining fungi. The wood is moderately resistant

to attack by dry-wood termites and is durable in

contact with the ground. It is also moderately

resistant to marine borers but contains no appreciable amount of silica, which is often associated

witli resistance to this marine animal.

Moca's high figure and attractive coloration

causes it to be used extensively for high-grade

furniture and cabinetwork and for many fancy

turned articles, such as billiard-cue butts, umbrella

handles, walking sticks, and police truncheons.

The wood has virtually no resonance, making it

particularly suitable for radio and television cabinets. It is also ixtilized in the Caribbean area for

heavy construction, bridge timbers, house framing,

and sheathing. Its good resistance to decay and

dry-wood termites should make it useful for poles,

posts, and other similar uses where durability is

important.

MOTILLO

Sloanea berteriana Choisy (elaeocarpus family, Elaeocarpaceae)

Motillo (fig. 60) is a very hard, heavy, strong

multicolored wood. The heartwood may be grayish, grayish yellow brown, yellowish brown, or a

uniform pinkish brown to cliocolate brown.

Heartwood is usually distinct from the yellowishcolored sapwood. Indistinct darker brown stripes

occur at irregular intervals in some specimens.

The wood has medium texture, low luster, irregular grain and it is without distinctive odor

or taste. It is not particularly attractive and

would be difficult to use for furniture because of

its many colors. However, the wood of a uniform

brown color would be suitable for many decorative

purposes. Air-dry wood weighs (U pounds per

cubic foot and green wood Tf) pounds per cubic

foot at 51 percent moisture content.

The wood air-seasons moderately well, drying

at a moderate rate Avith a moderate amount of

'leyrade. Green luml>er U/g inches thick airseasons to 16 percent moisture content in 4 to 5

months under cover in the San Juan area. A

slight to moderate amount of warp and surface

checking occurs during the seasoning process.

Shrinkage is moderate and uniform during seasoning. Green wood shrinks about %o "^ch (2.4

])ercent) per foot across the growth rings and %6

inch (4.5 percent) per foot along the growth rings

in seasoning to 15 percent moisture content.

Motillo works fairly well and produces good

to excellent surfaces in all machining operations.

But it takes screws and nails poorly, requiring

lead holes when screws are used and preboring

before nailing.

The wood is moderately resistant to dry-wood

termites, rating slightly below Honduras mahogany in this respect. It is probably not durable

in the ground nor resistant to marine borers, although definite information is lacking.
PUERTO RTCAN WOODS 79

While the wood lacks the attractiveness for furniture and cabinetwork, it is sufficiently hard,

heavy, and strong for all types of heavy construction, farm implement parts, handles, heavy-duty

flooring, boat parts, and piling in areas free of

the wood-eating teredos.

41

'il^

I '''IM lilt

^íñMi

1 inch

F—495367

FIGURE 60.—Jlotillo : Top, ñatsawed ; 'bottom,

quartersawed.

NEGRA LORA

Matayba domingensis (DC.) Radlk. (soapberry family, Sapindaceae)

Negra lora is an attractive, very hard, strong

wood. The heartwood (hg. 61 ) is a uniform pinkish brown and not easily distinguished from the

lighter colored sapwoocl. The wood is fine-textured and moderately lustrous. It has a distinctive foul odor. The grain is usually irregular

and interlocked. Growth rings are not easily distinguished. It is a heavy Avood, weighing .54

pounds per cubic foot air-dry and 72 pounds in

the green condition.

The wood seasons slowly but fairly well. Green

li/g-inch lumber air-dries to 19 percent moisture

content in about 7 months under cover in the San

Juan area. Slight cup, bow, and crook, and moderate twist, surface checking, and end defects develop during the slow seasoning process

Shrinkage is uniform but greater than the average for woods of similar density. Green wood

shrinks 1/3 inch (2.7 percent) per foot in width

across the growth rings and %e ii^cli (4.8 percent)

per foot along the growth rings in seasoning to

the air-dry condition. Sap-staining fungi are

seldom a problem in seasoning this wood.

Xegra lora is moderately difficult to saw and

machine and has an appreciable dulling efl'ect on

cutting edges. Machined surfaces are of good

quality in all operations except planing, in wliich

the irregular grain causes considerable coarse fuzziness and tearing. Despite its roey grain, negra

lora splits rather easily when screws are driven.

It should glue well and take all stains and polishes satisfactorily. The wood is very susceptible
80 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

1 inch

F 4-3536

FiGUüE 61.—Xpsra lora : Top, flatsawed ; hottom,

quartersawed.

to damage by dry-wood termintes and other

insects.

Negra lora is well suited for furniture, cabinetwoi-k, turnery, interior trim, flooring, and other

products which recjuire an attractive wood that

works well but that need not be durable. The

wood should also be useful for handles, agricultural implements, cartwrights' work of all types,

cart and vehicle bodies, and other uses where its

hardness and strength are a consideration. It

would also be suitable for both light and heavy

construction of all types where durability is not

a factor and, after preserv^ative treatment, for

posts and poles.

NEMOCÁ

Ocotea spathulata Mez (laurel family, Lauraceae)

Xemocá is characterized by an unusual array

of coloration and figure and is easily the most

unusual and perhaps the most attractively figured

commercial wood that grows in Puerto Rico (fig.

62). Color of the heartwood may be light pinkish

brown, yellowish brown, or greenish brown, interspersed with areas of dark brown to black stripes,

scratches, spots, or wavy irregular lines. This

intermingling of darkei- and lighter areas is so

complete that no two pieces of heartwood are

exactly alike.

The clearly defined sapwc^od varies from a yellowish brown on the outer edge to a pinkish brown

towards tlie interior; it lacks the dark markings

and variegated cliai-K-teristics of the heartwood.

The wood lias line textiu'e, medium luster, and

generally interlocked arain. firowth riri<rs are

not distinct. The wood has no odor or taste.

Nemocá is hard, heavy, and strong, weighing 47

pounds per cubic foot when air-dry and 62 pounds

gi'een.

The wood is moderately difficult to air-season.

Green lumber air-seasons at a moderate rate,

reaching 17 percent moisture content in 5 to 6

months under cover in the San Juan area. Moderate degrade occurs during drying in the form

of vei-y slight cup and surface checking, slight

to moderate twist, and moderate bow and crook.

Degrade is more severe in the darkest colored

wood coming from the heart of the tree. Shrinkage, i)articularly for a wood of nemocá's density,

is moderate and fairly uniform. Green wood

shrinks at the rate of %o "^ch (1.8 percent) per

foot in width across the growth rings and y^o

inch (o.-l percent) per foot along the growth
PUERTO RICAN WOODS 81

rings in drying to 15 percent moisture content.

Nemocá is moderately difficult to work because

of its hardness and interlocked grain, but it gives

good to excellent results in all machining properties except planing, in which there is considerable pickup and tearing. The roey grain, which

is responsible for the difficulty in planing is,

however, what gives the wood good resistance to

screw splitting. Nemocá can be sanded to a very

smooth surface; it will take all types of finishes

and polishes satisfactorily.

Certain other species of Ocotea are highly resistant to insects and decay, but on the basis of recent tests nemocá is very susceptible to dry-wood

termites. Its durability in the ground and in

teredo-infested Avaters is unknown. Pinliole

borers are not a serious problem in the logs, and

sap-staining fungi are not troublesome during

seasoning.

The heartwood possesses the attractiveness,

good working properties, and favorable technical

properties for furniture, cabinetmaking, paneling,

turnery, boat planking, farm implements, handles,

heavy construction of all types, bridge building,

and piling in nonteredo areas. The rather wide

uniform-colored sapwood could be used for flooring, interior trim, millwork, and other products

for which a light-colored uniform wood is preferred. The heavily variegated wood should

make unusually attractive tuimings and novelty

items.

,' ,Vr M •:'S: -.

t\

1 inch F-49Ó359

FIGURE 62.—Xemoeá ; TOIL flatsawed ; 'bottom,

qnartersawed.

NUEZ MOSCADA

Ocotea moschata (Meisn.) Mez (laurel family, Lauraceae)

Nuez moscada logs are of medium to large size,

good length, and exceptionally free from knots

and other defects. The Avood (fig. 63) resembles

nemocá in general appearance and density. The

heartwood is extremely variable in color and figuration, ranging from a medium brown to dark

brown with irregular darker bi'own to black

streaks or patches. The sapwood is yellowish

to light brown and fairly distinct from the heartwood. The unusual appearance of the heartwood

gives the wood an attractiveness that should make

it higlily acceptable for certain decorative

purposes.

The wood has medium to fine texture, interlocked grain, medium luster, and is Avithout distinctive odor or taste Avhen dry. GroAvth rings

are distinct. Air-dry Avood weighs about -14

pounds per cubic foot and green Avood 60 pounds

per cubic foot.

Xuez moscada air-seasons satisfactorily. Green

IVï^-inch lumber di'ies rapidly under coA'er in the

San Juan area, reaching 18 percent moisture content in about 4 months after piling. A small

amount of warping develops during seasoning,

l)ut no surface checking. Tlie heavy, dark-colored

Avood from the center of the tree appears to be

most susceptible to degrade.

Shrinkage is moderate and uniform during

sea.soning, but after manufacture the AA'ood tends

to twist if not held securely in place. Green

wood shrinks at the rate of ^2 inch (1.8 percent)

per foot in Avidth across the groAvth rings and

3/s inch (o.l percent) per foot along the growth

rings in seasoning to 1.") percent moisture content.

Nuez moscada is moderately easy to saAv and

machine, with good to excellent results in all operations except planing, in which considerable pickup

occurs because of interlocked grain. It takes
82 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

i '¡•if

screws and nails well without splitting, sands to

a smooth, even surface, and can be painted or

varnished satisfactorily without the need of

fillers.

Dry-wood termites readily attack this w'ood,

and it is presumably very susceptible to other

insects, decay-causing fungi, and marine borers.

Sap-staining fungi are not troublesome during

seasoning or in the logs.

Xuez moscada is recommended for turning,

furniture, cabinetmaking, novelty items, and other

uses requiring an attractive wood that'has good

strength and satisfactory working qualities. It

should also be satisfactory for both light and

heavy construction, bridge timbers, heavy crating,

and packing boxes. The highly figured heartwood should be acceptable for interior trim, paneling, and similar products where an unusual and

highly figured wood is desired. Wood that is

uniform in color may be useful for the same purjîoses and possibly for flooring.

1 inch

F-4Í15370

FIGURE 6.3.—Nuez moscada : Top, flatsawed ; bottom,

quartersawed.

PALO COLORADO

Cyrilla racemiflora L. (cyrilla family, Cyrillaceae)

The huge, centuries-old palo colorado trees of

the upper mountain rain forests provide a limited

volume of short but exceedingly large and generally hollow logs. The hollow trees are favorite

nesting places of the native Puerto Rican parrot.

Tlie wood is very attractive but develops exceedingly severe degrade durnig seasoning. which

limits its utility as a commercial wood. The most

common English name for this wood is swamp

cyrilla.

Seasoned heart wood (fig. 64-) is an attractive

dark reddish bl'own, with the most deeply colored

specimens being somewhat oily. The sapwood is

lighter brown and not clearly demarcated from the

heartwood. The wood has fine and uniform texture, lieaA'ily interlocked grain, and moderate to

low luster. Growtli rings, which are formed

;in)iually, are distinct. Distinctive odor and taste

uie lacking in seasoned wood. On the basis of

rough determinations, air-dry wood weighs about

59 pounds per cubic foot and green wood 72

pounds per cubic foot at 118 percent moisture

content.

Palo colorado seasons very slowly and undergoes exceptionally severe degrade. In the San

Juan area, green lumber li/g inches thick requires

10 months or longer under cover to reach an airdry moisture content of 19 percent. Even with

slow seasoning, exceedingly severe warp, surface

checking, end splitting, casehardening, collapse,

and honey combing develop in each piece during

the process. Degrade is so severe that air-dry

lumber is unfit for most commercial uses.

The wood also undergoes exceptionally high

shrinkage during seasoning. Measurements made

on a large number of severely distorted samples

indicate that green lumber shrinks %o ii^^h (5.0

percent) per foot in width across the annual rings
PUERTO RICAN WOODS 83

and 11^ inches (10.3 percent) per foot in width

parallel to the annual rings in drying to 15 percent moisture content. Its longitudinal shrinkage

of 0.31 percent is also unusually high, even for a

wood with interlocked grain, which is an indication of poor seasoning.

Palo colorado is relatively easy to saw and

machine unless severe casehardening or other internal defects are present. Except for scratches

that show in sanding unless fine abrasive paper is

used, the wood gives good to excellent results in

all machining properties. It is also very resistant

to screw splitting, because of its fine and tightly

interlocked grain. Machined surfaces are glossy

smooth, and the darker pieces often have a somewhat waxy or oily feel.

Palo colorado is very susceptible to dry-wood

termites and presumably other insects. It is considered durable in the ground, although specific

data are lacking. Because of the wood's extremely

poor seasoning characteristics and its heavy and

uneven shrinkage, its most satisfactory use is in

the green condition, and then only in submerged

places or other locations where drying will not

take place. This includes such uses as submerged

or buried piling, underwater parts of docks and

wharves, posts, and heavj^ construction on or beneath the ground. However, if some satisfactory

seasoning method could be found, this species

would be useful for many purposes requiring a

decorative wood that has good machining

characteristics.

1 inch

F—195371

FIGURE 64.—Palo colorado : Top, flatsawed ; iottom,

quartersawed.

PALO DE HUESO

Haenianthus salicifolius Griseb. (olive family, Oleaceae)

Palo de hueso (formerly known as Haenianthus

ohovatus Krug & Urban) belongs to a small genus

of two or three species limited to the Greater

Antilles of the Caribbean area. It is an extremely

hard, heavy, strong wood, and somewhat bizarre

in appearance (fig. 65).

The heartwood is golden brown to chocolate

brown, with wide alternate light and dark colored

stripes showing on quartersawed surfaces. The

sapwood is lighter in color and merges gradually

into the heartwood. The wood has fine texture,

fairly high luster, and usually interlocked grain.

Growth rings are not distinct. Seasoned wood has

no characteristic odor or taste. Air-dry wood

weighs 61 pounds per cubic foot and green wood

about 77 pounds per cubic foot at 52 percent moisture content.

The wood seasons at a moderate rate. Green

lumber air-dries to about 17 percent moisture content in 6 months under cover in the San Juan area

Very slight cup and crook, slight twist, and moderate bow occur during the air-seasoning process.

A minor amount of surface and end checking also

develops.

Palo de hueso undergoes moderate and unusually uniform shrinkage during seasoning for

a wood of its density. The shrinkage of 14 inch

(2.2 percent) per foot in width across the growth -

rings and % inch (3.5 percent) per foot in width

I^arallel to the growth rings in seasoning from

green to air-dry is considerably below the values

for many other commercial woods of similar

density. Its longitudinal shrinkage of 0.096 percent is also nominal for a woocl having interlocked grain.

Palo de hueso is rather difficult to woi'k because

of its density and hardness. Results in the different machining operations vary. The wood is difficult to plane; frequent long, continuous strips

of torn fibers and coarse fuzziness develop in many
84 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 205

îlîi

;'

Í

mi

Í [y'^'i

11 ¡. 'I ,t Í :

; 1 I'. , I

H,ih:t'', .MS :i'

s^isaiilfr«'! Vri''

L J

1 inch F-495372

FIGURE 6.5.—Palo de hueso : Top, flatsawed ; bottom,

quartersawed.

pieces. The presence of tension wood and its

gelatinous fibers, much like the condition found

in Honduras mahogany, accounts for the difficulty

in planing. For the same reason, the wood gi^^es

only fair results in shaping, but it is a good turning wood, and produces excellent results in boring

and moi'tising. It is a fairly good wood to sand

and lias fair resistance to screw splitting. Wherever defects are not present, the machined surfaces are exceptionally smooth and can be sanded

to a glass-like finish.

Dry-wood termites attack and destroy palo de

hueso without diíRculty, and pinhole borers attack

the sapwood of logs but are not apt to damage the

Jieartwood. Neither logs nor freshly cut lumber

are subject to discoloration by sap-staining fungi.

Judging from closely related species, the wood

probably is fairly resistant to decay in the ground.

Palo de hueso is well suited for uses where an

exceptionally heavy, strong, hard wood is required.

It should be most suitable for turnings, novelty

items, handles, machine parts, heavy construction,

boat frames, heavy-duty flooring, work benches,

bridge timbers, and piling in nonteredo areas. It

is not particularly good for furniture and cabinetwork because of its heaviness, poor working

qualities, and rather unattractive appearance.

PALO DE MATOS

Ormosia krugii Urban (legume family, Leguminosae)

Palo de matos is a medium-weight, somewhat

coarse-textured wood. The heartwood (fig. 66)

is a uniform salmon color with occasional darker

colored streaks, and it is not distinct from the

yellowish sapwood. Unfinished wood has moderate luster, and feels somewhat coarse or rough to

the touch. The wood has moderately coarse texture, generally coarse and irregular grain, indistinct growth rings, and is without distinctive odor

and taste. Large open pores that occur in rows,

groups, and singly are visible to the naked eye on

the end grain. Air-dry wood weighs .37 pounds

per cubic foot and green wood 70 pounds at 124

percent moisture content.

The wood air-seasoned slowly, requiring about

6 nioiitlis to i-eacli an air-dry moisture content of

16 percent in

1111

the Sun Juan area. Seasonina: is

;ux'0)ii])auiea by moderate degrade in the form of

modérât« bow, slight cup and twist, and very

slight crook, surface checking, and end splitting.

Directional shrinkage is moclerate but relatively

uneven. Green wood shrinks at the rate of %

inch (1.1 percent) per foot in width across the

growth rings and % inch (3.0 percent) per foot

parallel to the growtli rings in seasoning to 15 percent moisture content.

Palo de matos saws and works easily in machining operations, with fair to good results. Although the wood is rated good in planing, shaping,

and sanding on the basis of smoothness of cut, the

machined surfaces are somewhat rough and difficult to finish. It is only a fair wood to turn, bore,

and mortise because of its tendency to tear and

crush in these operations. It has good resistance

to screw splitting and probably takes and holds

nails well. It finishes and polishes satisfactorily
PUERTO RICAN WOODS 85

but requires considerable sanding and the use of

a filter before application of varnish or other

finishes.

The Avood is very susceptible to damage by drywood termites, and it probably is also quite susceptible to decay and marine borers. Sap-staining

fungi are not particularly troublesome during

seasoning.

On the basis of limited tests of a closely related

species growing in Brazil, palo de matos is considered fairly strong, hard, and tough for its density and may possess good bending properties.

The Puerto Rican species is quite attractive after

finishing and should be suitable for furniture, millwork, interior and exterior construction, boxes,

crates, concrete work, general carpentry, and

possibly for bent items and utility veneer.

'^'•^^ÍM.^í'

lpj[m'^ ^'^ ~ "? ''\mw^'^'^ '\ \

F—49537S

FiGUBE 66.—Palo de matos : Top, flatsawed ; bottom,

quartersawed.

PANAPEN

Artocarpus altilis (Parkinson) Fosberg (mulberry family, Moraceae)

Panapén, or breadfruit, is a very soft, lightweight wood, yet quite firm and strong for its

weight. The seasoned heartwood (fig. 67) is

golden colored, sometimes flecked with orange, and

clearly distinguished from the light-yellow to

yellowish-brown sapwood. Numerous large, open

pores are visible on the end grain and show on

the side surfaces as closely spaced lines or scratches,

giving the wood a coarse, uneven appearance. Although the w^ood's luster is low, well-sanded surfaces are fairly smooth, resembling oak in texture,

and they are quite attractive because of their

pleasing golden color. The grain is irregular and

at times interlocked. Growth rings are not apparent. There is no characteristic odor or taste.

Air-dry wood Aveighs 20 pounds per cubic foot.

The amount of moisture in green wood increases

from the sapAvood towards the center of the tree.

Material averaging 124 percent moisture content

in the Puerto Rican tests weighed 38 pounds per

cubic foot.

The high moisture content of the green Avood

makes it moderately difficult to season. Freshly

cut AYOod air-seasons at a moderate rate, reaching

19 percent moisture content in 5 months under

coA^er in the San Juan area. Well-seasoned material frequently contains pockets of moisture Avell

above the moisture content of the surrounding

AYOod. A moderate amount of Avarping occurs

during air-drying, but no noticeable surface or

end checking. Shrinkage is moderate and someAvhat uneA^en. Green Avood shrinks at the rate of

Vg inch (1.0 percent) per foot in Avidth across the

grain and 1/3 inch (2.7 percent) per foot parallel

to tlie grain in drying to 15 percent moisture

content.
86 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 205

^, ...,.,,..^,^

4'

1 ;w

t

I

I : '

1 inch

F—195374

FIGURE 67.—Panapen : Tot), flatsawed : hottom, quarter-

.sawed.

Panapen works easily with either power or hand

tools, but with generally poor results. Sawed

surfaces are inclined to be fuzzy, particularly in

ripping, although seasoned wood saws more easily

and with less fuzziness than green wood. In the

Puerto Rican tests, panapen gave only fair results in planing, because of frequent torn grain

and fuzzy surfaces; poor results in sanding because of the visible scratclies and fuzziness that

occur; and very poor results in shaping, turning,

boring, and mortising because of the extreme ease

with which the wood cruslies, tears, and fuzzes in

these operations. However, with special care and

using thin cutting edges and reduced spindle

speed, tlie wood should work satisfactorily. Moisture pockets probably are responsible for some of

the machining defects.

Panapén's resistance to attack by dry-wood

termites is very low. It probably is also veiy susceptible to decay and to attack by marine borers.

Logs sliould be removed from the forest soon after

felling to avoid damage by pinhole borers and sapstain. Fungi will also quickly discolor the sapwood of lumber unless it is either surface-dried

immediately after sawing or treated with a

fungicide.

The wood lacks the strength, hardness, and attractiveness necessary for cabinetmaking, furniture, and similar uses. However, it is suitable for

boxes, crates, interior sheathing, light construction, toys, and similar products. After preservative treatment, the wood could be used for sheathing, siding, and other exterior uses for which a

light, easily nailed wood of moderate strength

is acceptable. It miglit also be suitable as a substitute for the lieavier grades of guano (balsa)

if special techniques were developed to improve

its machining characteristics.

ROBLE BLANCO (ROBLE)

Tabebuia heterophylla (DC.) Britton (trumpet-creeper family, Bignoniaceae)

This wood is called roble blanco, or I'oble,

meaning oak and white oak in Spanisli, because

of its superficial resemblance (fig. 68) to plainsawed oak, although the wood lacks the characteristic wide rays of the oak group.

Tlie heart wood is light brown with a grayish

or somewhat golden hue. Fine lines of browncolored parenchyma provide the wood with a distinctive and characteristic figure on quartersaw^ed

surfaces and an attractive featherlike pattern on

flatsawed surfaces. The sapwood is so similar in

color to the heartwood that it is very difficult to

separate the two.

The grain is straiglit to interlocked, with a distinct ribbon stripe showing on quartersawed surfaces wliere interlocked grain is present. The

textine is inrdium to coarse, the luster is low to

medium, and no distinct odor or taste is apparent in seasoned wood. The wood is comparatively

heavy, weighing 42 pounds air-dry and 59 pounds

green.

Roble blanco is a fairly easy wood to season.

Green wood air-seasons rapidly with only moderate bow and very slight twist. Other forms of

warp and surface checking were not evident in the

Puerto Rican tests. Green li/g-inch lumber

reaches an air-dry moisture content of about 17

percent in 4 months or less under cover in the San

Juan area. The wood is also reported to kiln-dry

with little degrade. Sap-staining fungi are not

apt to be troublesome during seasoning.

The wood undergoes moderate and unusually

uniform slirinkage during seasoning. Green
PUERTO RICAN WOODS 87

wood shrinks at the rate of Vs inch (1.2 percent)

per foot in widtli across the growth rings and %«

inch (1.6 percent) per foot parallel to the growth

rings in seasoning to 15 percent moisture content.

Its longtitudinal slirinkage of 0.18 percent is normal for a wood with interlocked gram.

Roble blanco saws and machines easily with

very satisfactory results in all operations except

planing, in which the interlocked grain causes

considerable pickup. It has fair resistance to

screw splitting, takes nails fairly well, and glues

easily. The wood accei^ts mahogany and oak

stains satisfactorily or can be finished naturally

with excellent results. A high polish can be obtained with all types of finishes.

Roble blanco is considered an excellent wood for

veneer, but it recjuires careful and thorough boiling before slicing or turning. Considerable care

must also be taken to avoid torn and rough surfaces during the veneering process. Quartercut

veneers have an exceptionally attractive mottled

figure, dry evenly to a ñat, smooth surface, and

possess good gluing properties.

The wood is tough and strong for its weight.

It is similar to white oak and ash in all mechanisal properties, particularly in stiffness, hardness,

shear, cleavage, and shock resistance.

Roble blanco is moderately durable in contact

with the ground, but it is very susceptible to attack

by termites and marine borers. It is rated only

fair in weathering characteristics; the unpainted

wood loses its smooth surface and develops considerable checking upon exposure to weather,

though it does remain free from warp.

In general, roble blanco is suitable for the same

uses as white oak and ash. Because of its good

working properties and attractiveness, the wood

is used extensively for furniture, cabinetwork, interior trim, and face veneer. It is also well suited

for use as flooring, millwork, boat decking, frames

and planking, handles of all types, sporting goods,

agricultural implements, and both light and heavy

FIGURE

' ?" ~T " "

,1 ''

Í.

I

i^«

inch

F—195375

1.—Roble blanco : Top, flatsawed ; bottom, quartersawed.

construction. The lower and less valuable grades

are suitable for boxes, crates, concrete forms, and

similar items. Roble blanco's moderate durability

in the soil results in a limited use for posts, poles,

and other products where durability is a factor.

SAMAN

Pithecellobium saman (Jacq.) Benth. (legume family, Leguminosae)

Samán is a moderately attractive wood that has

some favorable characteristics, but it is often

valued more as an ornamental than for its wood.

The tree is often known as the rain-tree. It is

not native to Puerto Rico but has become widely

naturalized after extensive planting over many

decades.

Freshly cut samán heartwood (fig. 69) is a dark

chocolate brown and distinct from the yellow to

light-cinnamon colored sapwood. Diy heartwood is light to golden brown with darker streaks,

resembling butternut {Juglans cinérea) of the

United States. The grain may be either straight

or irregular: wood from slow-growing trees tends

to be more cross grained and have a darker color

than that from fast-growing trees. The texture

is medium to coarse, the luster is medium, and

there is no distinctive odor or taste. Samán is

soft and light, weighing 33 pounds when air-dry

and 68 pounds when green at 145 percent moisture

content.

Because of the wood's very high moisture content, about 6 months is required to air-di-j- green

wood to 17 percent moisture content in the San
88 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

• %, 4* f'y*y '

L

'f.

«v;

il,

1 inch

F—195376

F'lGUKE 69.—Samán : Top, flatsawed : hottom,

qnartersawed.

.Iiiaii area. It also seasons rather poorly, Avitli

considerable degrade : moderate to severe bow and

crook, slight twist, and very slight cup. But surface checking or end splitting were not observed in

the Puerto Rican tests. Sap-staining fungi may

also develop on freshly sawed wood.

Samán undergoes uniform and exceptionally

low shrinkage during seasoning. Green wood

shrinks y^o inch (0.7 percent) across the grain

and Vg inch (1.2 percent) along the grain per foot

in width in drying to an air-dry moisture content

of 15 percent.

This wood saws and machines easily but usually

develops torn grain and fuzziness in pieces containing irregular grain. In the tests, samán was

rated poor in turning, fair in shaping and boring,

and moderately good in planing, mortising, sanding, and screw splitting. It would probably machine satisfactorily with special handling and the

use of more suitable machining techniques. Wellprepared material glues satisfactorily and takes

an excellent finish with laccjuer or varnish.

Samán is rated durable to very durable in respect to decay and is resistant to attack by drywood termites, rating well above Mexican mahogany and slightly above teak in this respect.

Though the tree is valued mainly for its beauty

and shade and to some extent for its sweet pods,

wdiich make excellent cattle feed, the lumber possesses an attractive grain and color. It is suitable

for some types of furniture and cabinetwork, and

for light construction, boxes and crates, house

framing, and millwork. Samán's good resistance

to decay and insects makes it suitable for special

uses where these qualities are important. Its light

weight and low, even shrinkage may also make

it suitable for patternmaking. It has been recommended for decorative veneer and plywood, interior trim, and paneling.

TABAIBA

Sapium laurocerasus Desf. (spurge family, Euphorbiaceae)

Tabaiba, or manzanillo (fig. 70), is a soft, lightweight wood of uniform pale-brown color

throughout. The texture is rather fine except for

the fairly numerous large inores, whicli are visible

to the naked eye on the end grain and appear as

fine scratches or stip])le marks on flatsawed surfaces. The grain is sometimes straight, more frequently tightly interlocked. The luster is medium.

Growth rings are not visible, and characteristic

odor and taste are not evident in seasoned wood.

Air-dry wood weighs 28 pounds per cubic foot and

green wood 46 pounds at i)B percent moisture

content.

The ^\-ood is moderately diificult to season.

(Trciiii lumber P^ inches thick air-seasons to r.bout

17 percent moisture content in 6 months under

cover in the San Juan area. A small amount of

degrade occurs in the form of very slight twist and

crook, slight cup, moderate bow, and slight surface checking. No end checking or casehardening were noted in the study. Green wood shrinks

about i/ie inch (0.6 percent) per foot in width

across the grain and %2 ii^cli (1.8 percent) per foot

along the grain in drying to 1.5 percent moisture

content. Sap-staining fungi are almost certain

to discolor freshly cut wood unless it is immediately immersed in a fungicide or allowed to

become surface-dry soon after conversion.

Tabaiba saw-s and works easily with either hand

ov power tools, with results vai-ying from excellent in planing to very poor in sanding. Sawed
PUERTO RICAN WOODS 89

surfaces tend to be woolly, especially along the

grain. Frequent tearing, crushing, and fuzziness

occur in all cutting operations except planing,

with fair to poor surfaces resulting under conventional machining conditions. Better results

could no doubt be attained if more favorable machining conditions were used particularly thinedged knives and saws and reduced spindle speeds.

The wood shows scratches readily in sanding

but works to a vei-y smooth surface when fine

abrasive paper is used. It has good resistance to

screw splitting. Gluing, staining, and polishing

should not be troublesome with well-sanded material.

Dry-wood termites and other insects, decaycausing fungi, and marine borers attack and

quickly damage this wood, thereby resistricting

it to uses where good durability is not essential.

Tabaiba is recommended for boxes, crates, interior

construction, and other uses requiring a light, soft,

moderately strong wood. The wood has been recommended for paper pulp and plywood and, after

preservative treatment, should be suitable for siding and other exterior uses.

U i í fi,

!-í ; uó

III tim f iifí

.¡n

'

., i '

\ '^'1^

1 inch

F—Í95377

FIGURE 70.—Tabaiba : Top, flatsawed ; bottom, quartersawed.

TABONUCO (GOMMIER)

Dacroydes excelsa Vahl (bursera family, Burseraceae)

Tabonuco, occasionally called candlewood,

is the best known and most extensively used wood

in the Puerto Rican forests. It is one of the most

plentiful timber species on the island. Long,

clear logs of large diameter are harvested from

centuries-old, hurricane-resistant trees in the rain

forests.

The heartwood (fig. 71) is a uniform brown

color with an overall pinkish cast when first cut,

turning a pinkish brown when seasoned and later

a lustrous brown when exposed. The narrow,

indistinct sapwood is an attractive grayish color.

The texture is fine to medium, and uniform. The

grain is more or less roey and commonly interlocked, creating an attractive ribbon stripe on the

side surfaces. The luster is high, sometimes satiny

in appearance. Growth rings are not distinct.

There is no distinctive odor or taste in seasoned

wood.

The wood is moderately heavy, weighing 40

pounds per cubic foot air-dry and 52 pounds

green. It is appreciably heavier than Mexican

mahogany but somewhat lighter than j-ellow

birch, which it resembles superficially.

Tabonuco air-seasons easily and satisfactoi'ily.

Green wood 1% inches thick air-dries rapidly

with only minor degrade in the form of ver\'

slight cup, slight bow, twist, and end checking,

and with no a2Dparent surface checking or casehardening, (ireen lumber will air-season to about

17 percent moisture content in 4 months under

cover in the San Juan area.

The wood undergoes moderate and uniform

shrinkage during seasoning and holds its place

well after manufacture. Green wood shrinks at

the i-ate of % inch (l.-t percent) per foot in width

across the growth rings and % inch (2.7 percent)

per foot along the growth rings in seasoning to 15
90 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 20 5

1 inch

F—405378

FIGURE 71.—Tabonuco : Toij, flat.sawed ; hottovi,

quartersawed.

percent moisture content. The heartvvood is not

particuliU'lj' susceptible to sap-staining fungi, but

the sapwood is often turned to a bluish gray by

fungus action.

Tabonuco is a moderately good machining

wood. It cuts and saws easily but, because of an

abundance of silica, rapidly dulls saw teeth and

other cutting edges. Fairly good surfaces are obtained in planing, mortising, sanding, and shaping. Turning and boring are more difficult; torn

grain and occasional fuzziness occur in specimens

having roey grain. The wood is easily glued and

holds nails well. Mechanical tests show tabonuco

to be moderately hard, tough, and strong, comparing well w'ith Mexican mahogany and yellow

birch. The wood takes stain well and finishes

beautifully with varnish or lacquer; it is very difficult to distinguish from mahogany when finished

to resemble that Avood.

Tabonuco is only slightly resistant to decay,

lasting 3 years or less in the ground, and it is very

susceptible to attack by both dry-wood and subterranean termites. Despite the presence of silica,

the wood was cjuickly desti'oyed by marine borers

in the Atlantic Avatei'S along the north coast of

Puerto Kico. Unfortunately, tabonuco is difficult

to impregnate w'ith preservatives by either pressure or nonpressure methods.

In Puerto Rico, tabonuco is used for all types

of furniture and for cabinetwork, interior trim,

and general construction and carpentiy. In other

areas of the Caribbean, it is used for crates, boxes,

shingles, and small boats. It should be suitable

for soft-drink cases, fruit and vegetable containers, and similar uses, and it has been recommended

for decorative veneer. The AVOOCI is used extensively in Puerto Rico as a substitute for mahogany

in furniture manufacture and could be substituted

for that wood in many other products.

TECA (TEAK)

Tectona grandis L.f. (verbena family, Verbenaceae)

Teca, teak in English, is one of the best known

and most highly valued timbers in the world.

The tree is native to southeastern Asia and Malaya

but has been planted successfully in Puerto Rico

and other areas in the American tropics.

Freshly cut lieartwood (fig. 72) is olive green

when freshly cut, becoming a golden brown upon

seasoning and exposure. The sapwood is yelloAvish to white in color and sharply demarcated from

the heartwood. Growth rings are distinct and,

except for occasional false rings, are of annual

occurrence. They show on the side surfaces as

narrow broAvn lines that are darker than the rest

of the heartwood.

Teca has unusually straight grain, uniformly

fine texture, an oily feel, and a strong, characteristic fragrance wlien fi-eslily cut. Seasoned wood

retains its oily feel but possesses only a faint fragrance and no detectable taste. Plantation-grown

wood from Puerto Rico averages 40 pounds per

cubic foot when air-dry and 62 pounds green.

The wood air-seasons easily and satisfactorily.

It also seasons rapidly, reaching 17 percent moisture content in 17 weeks under cover in the San

Juan area. A minor amount of Avarping occurs

during air-seasoning, but no surface checking or

casehardening. Teca kiln-dries sloAvly but A^ery

well, Avith little tendency to check, split, or Avarp.

HoAvever, considerable variation occurs in the drying rate of individual boards.

The wood is Avell known for its IOAV and uniform

shrinkage and excellent stability after manufacture and, accordingly, is the only Avood acceptable

for decking on aircraft carriers and other large
PUERTO RICAN WOODS 91

vessels. Green wood shrinks approximately i/ie

inch (0.5 percent) per foot in width across the

growth rings and about Vs inch (1.1 percent)

along the growth rings in seasoning to 15 percent

moisture content.

Teca is, in general, comparable to white oak

in strength. Plantation-grown wood is equally

as strong as forest-grown wood. Air-dry wood

averages'about 10 to 20 percent stronger in bending and stiffness than oak but is inferior in hardness by a like amount.

Plantation-grown teca works easily with both

hand and power tools, but it contains silica which

dulls cuttnig edges. Special carbide or other

high-quality steel cutting edges are recommended,

although ordinary good-quality knives are used

successfully with reduced spindle speeds.

In the tests, teca gave good to excellent results

in all operations except sanding, in which very

fine abrasives are required to prevent visible

scratching of the woocl. Under ordinary conditions there is a tendency for roughness to occur

on the end grain in shaping operations. Teca

takes nails fairly well, glues moderately well

despite its oily nature, ancl can be varnished and

polished with good results. It is a moderately

good wood for steam bending, but it is likely to

buckle on the concave surface if bent to a small

radius of curvature.

The heartwood is resistant to attack by dry-wood

termites, being comparable to West Indies mahogany [Svietenia mahagoni) in this respect. It is

also moderately resistant to subterranean termites

and A'ery durable in the ground, but it is readily

attackecl by marine borers. The sapwood shares

none of the durability properties of the heartwood,

being readily attacked by all the above-named

organisms in addition to being vidnerable to

damage by pinhole borers.

The heartwood is extremely difficult to impregnate with preservatives, because only the vessels

absorb the solution. The sapwood is not difficult

to treat and can be impregnated successfully by

the open-tank process. Treating the outer sapwood layer of small round or split posts by this

method adds considerably to their service life.

Unpainted wood possesses excellent weathering

characteristics and is almost entirely free from

warp and checking when exposed without the

protection of paint.

1 inch

F—195379

FIGURE 72.—Teca : Top, flatsawed ; iottom, quartersawed.

Teca is best known for its extensive use in ship

decking, for Avhich no other wood is its equal. It

has many other uses, including flooring, joinery,

interior trim, dural)le outdoor structural work,

door and window frames, carvings, furniture,

doors, interior paneling, and fancy turned items.

The wood's low and even shrinkage, stability, and

durability suits it exceptionally well for tanks and

vats. Because of its high resistance to acids, the

wood is also very useful in laboratories and chemical plants for l:)enches and other fixtures. Thinnings from teca plantations are often split and

used in the manufacture of wire fencing, squared

for house framing, treated and used as round

posts, or sawed into lumber for furniture.

UCAR

Bucida buceras L. (corabretum family, Combretaceae)

Ucar is also known in English as oxhorn bucida.

Short logs of medium to large diameter are obtained in limited numbers from the semiarid

forests along the south coast of Puerto Rico.

The wood of ucar is very hard, heavy, and

strong. The attractive heartwood (fig. 73) frequently has a roey grain. It is a dark greenish

brown clearly demarcated from the yellowish to

light-brown sapwood. Longitudinal stripes are

freciuent as a result of the roey grain, giving the

wood an attractive figure on the side surfaces. The

wood is moderately fine in texture, very lustrous,
92 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 205

A- ÎPÇfH^« ä|' '/ \f %'»' »íl^tó*.

i M

f ,

;f , t

1 inch

F-495380

FIGURE 7.3.—Ucar : Top, flatsawed ; bottom, quartersawed.

and without distinct growth rings. Althoug'li

green wood lias a tarry odor, seasoned wood has no

characteristic odor or taste. Air-dry wood weighs

about 69 pounds per cubic foot and green wood

about 79 pounds per cubic foot, making it one of

the heaviest woods available for general use on

the island.

The wood is moderately easy to season; it airdries satisfactorily for a timber of its high density.

Green li/g-inch lumber air-seasons to Í7 percent

moisture content in 6 months under cover in the

San Juan area. A moderate amount of warping

and surface checking and a minor amount of

end checking occur during the seasoning process.

Shrinkage is unusually low and uniform for a

wood of its density. Green wood shrinks %2 ii^ch

(1.3 percent) ¡Der foot across the growth rings

and %2 inch (2.3 percent) per foot along the

growth rings during seasoning to an air-dry

moisture content of 1.5 percent.

Ucar is rather difficult to saw and machine with

power tools and is very hard to work with hand

tools because of its very high density and hardness.

However, very smooth glasslike surfaces are obtained in all operations except planing, in which

torn grain is troublesome in pieces containing

roey grain.

Although good, clean holes can be cut in boring

and mortising, the bits tend to heat and char the

interior of the holes. If sufficient power is available, charring can be prevented by an increased

rate of speed. Because the wood is easily split

by screws or nails, it is necessary to prebore sufficiently large lead holes to reduce splitting toan

acceptable minimum. Well-sanded wood takes an

excellent polish with all types of finishes.

Ucar is resistant to dry-wood termites and durable in contact with the ground, but it is not considered resistant to marine borers. Its resistance

to impregnation with preservatives is probably

high. Sap-staining fungi, pinhole borers, and

other insects are not troublesome in either the logs

or sawed lumber.

Ucar is a poor bending wood, but it is otherwise an exceptionally strong w-ood, resembling

greenheart (Ocotea rodiael) in both weight and

strength properties. It is sawed into lumber and

planks in Puerto Rico and is used in carts, gates,

wooden fences, and occasionally for the construction and repair of farm buildings. Ucar is also

particularly well suited for heavy-duty flooring,

work benches, machinery platforms, and heavy,

durable exterior construction of all types. The

wood is not suitable for decorative purposes in

furniture and cabinetmaking and is too difficult

to work for general building purposes. Because

of its great strength and good durability, ucar is

used in other countries for railway ties, piling in

nonteredo areas, house posts, and to some extent

for bridge timbers. The wood may be suitable for

certain machinery parts and sporting goods requiring a heavy, hard, and extremely strong wood.

Its technical properties also indicate that it might

be useful as a substitute for greenheart except for

marine use in teredo-infested waters.

YAGRUMO HEMBRA

Cecropia peltata L. (mulberry family, Moraceae)

Yagrumo hembra is one of the lightest woods

growing in Puerto Rico, but it is especially tough

for its weight. The tree grows rapidly and is short

lived, producing small to medium-size logs with a

cliaractei'istic hollow between the nodes. It is

frequently called trumpet-tree in English.

The wood (fig. 74), which appears to be all

sapwood, is whitish when freshly cut, becoming a

pale-brown to oatmeal color upon exposure. It

is soft but fairly lustrous, coarse textured, and

generally straight grained. Green wood, containing 125 percent moisture content, weighs 41
PUERTO RICAN WOODS 93

pounds per cubic foot. Air-dry wood at 15 percent moisture content weighs about 22 pounds per

cubic foot as compared with an average of K

pounds for guano growing in Puerto Rico.

The wood seasons rapidly, reaching a moistnre

content of about 17 percent in 14 weeks when

piled under coA^er in the San Juan area. In the

initial tests, air-seasoning was accompanied by

rather severe bow and twist, and moderate cupping and crook." However, it usually seasons

without noticeable surface checking or end splitting. Some difficulty is encountered with sapstaining fungi if the lumber is not treated with

a fungicide or allowed to become surface-dry immediately after sawing.

Yagrumo hembra underwent moderate but exceptionally uneven shrinkage during the initial

seasoning tests. Shrinkage from green to ovendry averaged 14 ii^ch (2.0 percent) across the

grain and % inch (6.2 percent) parallel to the

grain per foot in width. The better than 3 to 1

ratio of tangential to radial shrinkage is unusually

high and accordingly subject to question.

Shrinkage from green to air-dry is normally about

one-half of these values.

Dry, seasoned wood is very easy to saw and

machine compared with green wood, which adheres to the face of circular saws. Because of

yagrumo hembra's soft wood, surfaces tend to tear

and fuzz in shaping and turning, and to crush or

crumble in boring and mortising. However, it

takes screws and nails readily, holds them firmly,

and gives good results in planing and sanding.

Trouble is often encountered in obtaining a

smooth finish with varnish or lacquer, because of

the soft, porous nature of the wood and a tendency for fuzziness to develop during the finishing

process.

Yagrumo hembra is very susceptible to decay,

termites, pinhole borers, and other insects and is

considered nondurable in contact with the ground.

It is used for match sticks, boxes and crates, excelsior, interior boarding, and other uses for which

° Later tests indicate that yagrumo hembra can be airseasoned quickly and without excessive degrade under

some conditions. This would also indicate a more favorable ratio of tangential to radial shrinkage than the

values listed here.

FIGURE 74.-

1 inch

F-459381

-Yagrumo hembra : Top, flatsawed ; 'bottom,

quartersawed.

a soft, easily worked wood of low durability and

strength is acceptable. The wood should be entirely acceptable as a substitute for guano in the

manufacture of toys, models of all types, and

other commercial products for which the moderately heavy grades of balsa are acceptable.

Yagrumo hembra is used for paper pulp in some

areas.

This wood is used in Puerto Rico for the manufacture of excelsior and, in combination with

cement, is made into a type of insulation board

suitable for certain light interior construction and

partitions.

YAGRUMO MACHO

Didymopanax morototoni (AUDI.) Dec. & Planch, (ginseng family, Araliaceae)

Yg,grumo macho, or matchwood, is a small to

medium-sized tree found only in the rain 7 -list in

openings created by clearing, hurricanes, or other

catastrophes. The wood (fig. 75) is a palebrownish color throughout, without distinction

between heartwood and sapwood. It is lustrous,

lias fairly fine texture and straight grain, and it is

soft and firm yet quite brittle. Air-dry wood

596033 o—61 7

weighs about 28 pounds per cubic foot and green

wood about 40 pounds per cubic foot at 81 percent moisture content.

Tlie wood seasons rapidly but with considerable

degrade. Green lumber li/g inches thick airseasons to about 16 percent moisture content in 14

weeks under cover in the San Juan area. Degrade

occurs as moderate to severe warping, but without
94 U.S. DEFT. OF AGRICULTURE HANDBOOK NO. 2 05

1 inch

F-159382

FIGURE 75.—Yagrumo macho : Top, flateawed ; lottom,

quartersawed.

apparent surface checking or end splitting. (îreen

lumber is discolored quickly after sawing by sapstaining fungi unless the surface moisture is lost

within a few hours or the wood is immersed in a

fungicide.

A rather high rate of shrinkage occurs during

seasoning for a wood of yagrumo macho's density,

l)ut this shrinkage is fairly uniform in the radial

and tangential directions. Green wood seasoned

to air-dry condition shrinks at thß rate of % inch

(3.1 percent) across the growth rings and % inch

(5.6 percent) along the growth rings per foot in

width.

Yagrumo macho works easily with either hand

or power tools. Good results are obtained in

planing, shaping, and sanding except for occasional fuzziness in some pieces. However, the

wood is difficult to turn, jjore, or mortise; excesSíA'C tearing and crushing of the fibers occurs during these operations. The use of very sharp and

thin cutting edges and reduced feed rates would

have improved the quality of the machined surfaces. The wood takes nails and screws very well

without splitting. Polishing is somewhat difficult,

wnth a tendency for woolliness to occur during

rubbing and after application of the finishes.

Yagrumo macho logs are very susceptible to

damage by pinhole borere unless removed from

the forest and converted into lumber soon after

felling. Seasoned lumber is A'ery susceptible to

termites and otlier insects, decay, and marine

borei-s; it requires ¡)reservative treatment for use

in exposed locations or in contact Avith the ground.

Yagrumo macho is an excellent wood for boxes

and crates, and it has been I'ecommended for match

splints, interior construction, utility grade i^lyAvood, and toys. It may also liaA'e good pulping

properties and should be suitable for many of the

same purposes as tlie heavier grades of guano

(balsa).
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1,116 pp. Belize.

LANG, W. G.

19.54. FOREST UTILIZATION IN SAINT LUCIA, BRITISH WEST

INDIES. Tropical Woods 1.5 : 120-123.

LONGWOOD, F. R.

1955. INDUSTRIAL WOOD IN PUERTO RICO. U.S. Forest

Serv. Caribbean Forester 16: 64r-97.

MIAMI UNIVERSITY MARINE LABOBATOBY.

1953. MARiNf. BORER CONFERENCE REPORT. Univ. Miami

Marine Lab. Rpt. ML-4719, [n.p.], illus.

[Processed.]

MURPHY, L. S.

1916. FORESTS OF PORTO RICO : PAST, PRESENT, AND FUTURE.

U.S. Dept. Agr. Bui. 3.54, 99 pp., illus.

PILLOW, M. Y.

1950. PRESENCE OF TENSION WOOD IN MAHOGANY IN RELATION TO LONGITUDINAL SHRINKAGE. U.S. FORest Prod. Lab. Rpt. 1763, 6 pp., illus.

RECORD, SAMUEL .1., AND HESS, ROBERT W.

1943. TIMBERS OF THE NEW WORLD. 640 pp., illUS. NtW

Haven, Conn.

REíD DAVID.

1942. CREOSOTE PENETRATION IN TABONUCO WOOD AS AFFECTED BY PEELIMINARY' BOILING TREATMENTS IN

ORGANIC SOLVENTS. U.S. Forest Serv. Carribbean Forester 4 : 23-24.

REMBLE, B. J.

1938. COMMERCIAL MAHOGANIES AND ALLIED TIMBERS.

Brit. Dept. Sei. and Indus. Res. Forest Prod.

Res. Bui. 18, 45 pp., illus. Princes Risborough.

England.

SAKS, EDGAB V.

1954. TROPICAL HARDWOODS FOR VENEER PRODUCTION IN

MEXICO. U.S. Forest Serv. Caribbean Forester

15: 112-119, illus.

SURINAM FOEEST SEEVICE.

1955. SURINAM TIMBEES. Surinam Forest Service, Ed.

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SWABEY, CHRISTOPHEE.

1941. THE PEINCIPAL TIMBEES OF JAMAICA. Jamaica

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TEESDALE, LAUEENCE V., AND GIEAED, JAMES W.

1945. WOOD UTILIZATION IN PUERTO RICO. U.S. Forest

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[Processed.]

TROOP, BENJAMIN S., AND AVANGAARD, FREDERICK F.

1950. THE GLUING CHARACTERISTICS OF CERTAIN TROPICAL

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WANGAARD, FREDERICK F., AND MUSCHLER, ARTHUR F.

1954. PROPERTIES AND USES OF TROPICAL WOODS, HI.

Tropical Woods 98 : 1-190, illus.

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19.54. PROPERTIES AND USES OF TROPICAL WOODS, IV.

Tropical Woods 99 : 1-187, illus.

STERN, WILLIAM L., AND GOODRICH, STANLEY L.

1955. PROPERTIES AND USES OF TROPICAL WOODS, V.

Tropical Woods 103 : 1-139, illus.

WELLWOOD, R. W.

1946. THE PHYSICAL-MECHANICAL PROPERTIES OF CERTAIN

WEST INDIES TIMBERS. U.S. Forest Serv. Caribbean Forester 7: 151-189.

WOLCOTT, G. N.

1940. A LIST OF WOODS ARRANGED ACCOEDING TO THEIB

RESISTANCE TO THE ATTACK OF THE "POLILLA,"

THE DEY-WOOD TERMITE OF THE WEST INDIES

(CBYPTOTERMES BREVIS WALKER). U.S. Forest

Serv. Caribbean Forester 1: 1-9.

1950. AN INDEX TO THE TERMITE-RESISTANCE OF WOODS.

Puerto Rico Col. Sta. Bui. 85, 26 pp.

WOODS, R. P.

19.51. TIMBEES OF SOUTH AMERICA. 77 pp., illus. Timber

Development Assoc. Ltd., London.
INDEX TO TIMBER DESCRIPTIONS

Page

Achiotillo 35

Aguacatillo 36

Alchornea latifolia 35

Algarrobo 36

Almacigo. 38

Almendra 39

American muskwood 58

Andira inermis 77

Angelin 77

Artocarpus altilis 85

Australian-pine 46

Ausubo 39

Balata 39

Balsa 57

Beakpod eucalyptus 52

Beilschmiedia péndula 55

Breadfruit 85

Buchenavia capitata 53

Bucida buceras 91

Bursera simaruba 38

Byrsonima coriácea 75

Cabbage angelin 77

Caimitillo 40

Caimitillo verde 41

Calophyllum brasiliense 74

Calycogonium squamulosum 65

Camasey negro 65

Candlewood 89

Caoba hondurena 42

Capá blanco 43

Capá prieto 44

Caracolillo 45

Casuarina 46

Casuarina equiseiifolia 46

Cecropia peltala 92

Cedrela adórala 47

Cedro hembra 47

Ceiba 48

Ceiba peniandra 48

Central American cedar 47

Clusia rosea 50

Cordia alliodora 44

Courbaril 36

Cucubano 49

Cupey 50

Cyrilla racemiflora 82

Dacroydes excelsa 89

Didymopanax morotoloni 93

Espino, rubial 51

Eucalipto : 52

Eucalyptus 52

Eucalyptus robusta 52

Eugenia slahlii 59

Ficus laevigata 63

Genipa 62

Genipa americana 62

Gommier 89

Granadino 53

Guaba 54

Guajón

Guama

Guano

Guaraguao 1

Ouarea trichilioides

Guayabota

Guettarda laevis

Gumbo-limbo

Haenianihus salicifolius

Hernandia sonora

Higüerillo

Homalium racemosum

Honduras mahogany

Hymenaea courbaril

Indian-almond 39

Inga laurina 56

Inga vera 54

Jácana 61

Jagua 62

Jagüey blanco 63

Jamaica nectandra 67

Jobo 64

Jusillo 65

Laurel amarillo 66

Laurel avispillo 67

Laurel geo 68

Laurel prieto 69

Laurel sabino 70

Mago 71

Magnolia splendens . 70

Mahogany, Mexican. 42

Mahogany, Honduras 42

Mamey 72

Mammea americana 72

Mangifera indica 73

Mango 73

Manilkara bidentata 39

Manzanillo gg

María ~__ 74

Maricao 75

Martinique prickly-ash 51

Masa 7g

Matchwood 93

Matayba domingensis 79

Meliosma herbertii 35

Mesa 4Q

Mexican mahogany 42

Mexican white birch 3g

Micropholis chrysophylloides 40

Micropholis garciniaefolia 4]^

Moca _ 77

Motillo ' ' ] 7g

Nectandra coriácea __ Q7

Nectandra membranácea go

Nectandra sintenisii gg

Negra lora __~ 70

Nemocá ~ QQ

Nuez moscada -81

97
98 U.S. DEPT. OF AGRICULTURE HANDBOOK NO. 2 05

Paire

Ochroma pyramidale 57

Ocotea leucoxylon 68

Ocolea moschala 81

Ocotea spalhulala 80

Ormosia krugii 84

Oxhorn bucida 91

Palo colorado 82

Palo de hueso 83

Palo de matos 84

Panapén 85

Petitia domingensis 43

Pühecellobium saman 87

Pouteria mulliflora 61

Rain-tree 87

Roble 86

Roble blanco 86

Samán 87

Santa maria 74

Sapiuîn laurocerasus 88

Shortleaf fig 63

Silk-cotton tree 48

Spondias mombin 64

Sloanea berteriana 78

Spanish cedar 47

Paife

Swamp cyrilla 82

Swamp mahogany 52

Swamp messmate 52

Swietenia macrophylla 42

Tabaiba 88

Tabebuia heterophylla 86

Tabonuco 89

Teak 90

Teca 90

Teciona grandis 90

Terminalia calappa 39

Telragaslris balsamifera 76

Trumpet-tree 92

Ucar 91

Vitex divaricata 60

West Indian locust 36

White fiddlewood 60

Yagrumo hembra 92

Yagrumo macho 93

Yellow mombin 64

Zanthoxylum mariinicense 51

U.S. GOVERNMENT PRINTING OFFICE: 1961 O—596033