Department of 

Agriculture 

Forest Service 

Southern Forest 

Experiment Station 

New Orleans, 

Louisiana 

Resource Bulletin 

SO-85 

October, 1982 

The Forest Resources 

of Puerto Rico 

Richard A. Birdsey and Peter L. Weaver 
ACKNOWLEDGEMENTS 

The assistance of the organizations listed below, and of the individuals in 

them, is gratefully acknowledged: 

Department of Natural Resources, Puerto Rico 

The University of Puerto Rico 

Southeastern Area State and Private Forestry, U.S. Forest Service 

Cover: 

Yourzp secorrdap forest in the t,zcrnl(v of tht 

Luqurllo Mounralrzs 
Contents 

Page 

HIGHLIGHTS .................................................................... 1 

THE FOREST EPJVIRONS1ENT .................................................. 2 

Major Forest Influences ......................................................... 2 

Geology and Physiography .................................................... 2 

Climate ...................................................................... 2 

Soils ......................................................................... 3 

Population and Land Use ..................................................... 5 

Description of the Forests ....................................................... 5 

Vegetation Classification and Forest Associations ............................... 5 

Forest Plantations ............................................................ 8 

Forest Resource Values ............................... .. ........................ 8 

Timber ...................................................................... 8 

Mangroves ................................................................... 9 

Water and Erosion Control .................................................... 10 

Rare and Endangered Plant Species ........................................... 11 

Wildlife ...................................................................... 12 

Recreation ................................................................... 12 

Overview of Research ......................................................... 13 

PREVIOUS FOREST SURVEYS AND ESTIMATES ................................ 16 

THE 1980 FOREST RESOURCE SURVEY ......................................... 20 

Survey Scope and Design ....................................................... 20 

Forest Ownership ............................................................... 21 

Forest Area .................................................................... 22 

Forest Land Increasing ....................................................... 22 

Timberland Increases Follow Retirement of Agricultural Land .................. 22 

Most Timberland in Rugged Mountain Areas ................................... 23 

Species Composition ............................................................ 25 

Species Represent Past Human Influence ...................................... 25 

Coffee Shade Forests Less Complex Than Secondary Forests ..................... 26 

Poor Tree Quality ............................................................ 27 

Timber Volume ................................................................. 27 

Most Volume in Abandoned Coffee Country .................................... 27 

Low Sawtimber Volume ....................................................... 28 

Commercial Prospects for Timberland ............................................ 28 

Management Opportunities ..................................................... 29 

Implications of this Study ....................................................... 31 

LITERATURE CITED ............................................................ 31 

APPENDIX ...................................................................... 35 

Survey Methods ................................................................ 36 

Reliability of the Data .......................................................... 36 

Definitions of Terms ............................................................ 37 

Standard Tables ................................................................ 39 

Unit Conversion Factors ........................................................ 57 

Metric Inventory Standards ..................................................... 57 

List of Tree Species Included in Standard Tables .................................. 58 
Teak planted along a roadside in the Rio Abajo forest. 
The F'G: st Resources of Puerto Rico 

Richard A. Birdsey and Peter L. Weaver 

HIGHLIGHTS 

In the spring of 1980 a forest inventory of Puerto Rico was initiated 

by the Southern Forest Experiment 

Station. The primary objective of 

this first survey was to assess the 

timber production potential of 

young secondary forests. The partitioning of the island into commercial and noncommercial survey regions and the concentration of fieldwork in potential commercial 

forests were major features of the 

survey. 

Forest area, timber volume, and 

species composition data were 

obtained by a sampling method involving a forest-nonforest classification on aerial photographs and 

on-the-ground measurements of 

trees at sample locations. The sample locations were at the intersections of a grid of lines spaced 3 kilometers apart. In the commercial 

survey region, 10,925 photographic 

classifications were made, 437 

ground locations were visited, and 

4,506 sample trees were selected. Field crews identified 189 tree 

species. 

Puerto Rico's forest area has increased dramatically in the last 30 

years, to 279,000 hectares. These 

young forests result from migration 

of the rural population away from 

marginally productive pasture and 

cropland, &lore than half of the 

forest land in Puerto Rico serves important nontimber needs, including 

watershed protection, wildlife habitat, and recreation. About 130,000 

hectares of forest land were classified as timberland, characterized by 

low volumes and stocking levels due 

Richard A. Btrdsey 1s Research Forester, Sout 

Research Forester, Southern Forest Experimf 

to past land abuse and unfavorable 

site characteristics. 

Much timberland occurs in rugged mountain regions with poor 

soils and high rainfall. Physical factors, especially steep slopes, can result in serious erosion if forest cover 

is removed. Deep volcanic soils in 

the dissected interior uplands, the 

favored coffee production area, support nearly half of the stocked 

timberland. 

Current species composition of 

timberland reflects prior land use. 

Most of the common species tallied 

were once used for coffee shade, 

fruit production, or ornament. Coffee shade forests generally contain 

fewer species than abandoned pasture or farmland and fewer small 

trees. Secondary forests have good 

management prospects because of 

potential timber species in the 

smaller diameter classes. The large 

timber species common in the mature forest are generally absent. 

Of the trees tallied, about half 

were classed as growing stock. In 

both coffee shade and other secondary forests, stands develop with 

many poor quality, open-grown 

trees. 

The highest timber volumes per 

hectare grow in deep volcanic soils. 

Sixty percent of the timber volume 

is in 10 species. Because of poor site 

quality, timber volume is generally 

less than 50 cubic meters per hectare. Sawtimber volume, averaging 

4 cubic meters per hectare, is less 

than one-tenth the timber volume. 

forest stands. Well-stocked poletimber stands offer the best opportunity for timber stand improvement, 

while nonstocked timberland and 

poorly stocked sapling-seedling 

stands could be planted with fast 

growing species. Enrichment planting of secondary forests and better 

management of coffee shade are 

alternatives for large areas of 

timberland. 

The data gathered in the survey 

can provide guidelines for an applied research program on secondary tropical forest management in 

Puerto Rico. The survey methods 

will also contribute to a developing 

body of knowledge on tropical forest 

inventory techniques, and should 

be valid for other tropical regions. 

Management opportunities are 

not clear-cut because of the diverse Limestone hilts near Arecibo. 

,hern Forest Experiment Statton, Forest Service-USDA, New Orleans, La. Peter L. Lveaver 1s 

?nt Station, Forest Service-CSDA, Inst~tute of Tropical Forestry, Rio Piedras, Puerto Rtco. 
THE FC <ST ENVIRONMENT 

Major Forest 

I[nf luences 

Puerto Rico is the eastern-most 

acd smallest of the Greater Antilles 

and is situated between 18"311 and 

17"55' N latitude and 65'37" and 

67"17' W longitude. The main island, about 160 kilometers long and 

55 kilometers wide, occupies about 

8,900 square kilometers including 

the offshore islands of Vieques, 

Culebra and Mona. The small 

mountainous island, lying directly in the path of the easterly 

tradewinds, shows a remarkable diversity in its physical environment 

(Pico 1974). The interrelations of 

local geology, physiography, climate, and soils influence the structure and composition of the forests. 

Nearly all forest areas have also 

been heavily influenced by man. 

Geology and PhysiographyThe geologic history of Puerto Rico 

began more than 100 million years 

ago during the Cretaceous period. A 

" - 

geosyncline elongated through the 

Antillean region, and active volcanism occurred until near the end of 

the Middle Eocene epoch, giving 

rise to predominantly submarine 

accumulations of volcanic rocks 

(Beinroth 1969). Limestones originated along with tuffaceous shales at 

this time. 

Extensive faulting and folding 

then occurred, accompanied by the 

emerging plutonic rocks which are 

now found in the vicinity of San 

Lorenzo and Utuado. The serpentine found in southwestern Puerto 

Rico probably intruded during the 

Cretaceous period. Later during the 

Middle Oligocene to Middle Miocene epochs, younger Tertiary 

limestones were formed. Slight uplift and tilting followed, about 15 

million years ago. 

The main island surface has 

several distinct regions (fig. 1). The 

Central Cordillera varies from 600- 

1340 meters elevation and runs 

from east to west, forming the principal hydrologic divide. It is located 

about 15 kilometers from the south 

coast and 40 kilometers from the 

north coast because of differential 

erosion. The Luquillo Mountains 

rise to 1074 meters in the northeast- - 

ern part of the island, and the Cayey 

Mountains, an extension of the Cordillera, rise to 900 meters in the 

southeastern part. The latter two 

are separated by the Caguas Valley. 

Foothills surround the mountains 

and merge into coastal lowlands. 

Forty-five percent of the land surface is above the 150 meter contour 

and half of that area has slopes 

greater than 45 percent. A quarter 

of the land surface is above the 300 

meter contour, and 60 percent of 

that area has slopes greater than 45 

percent (Wadsworth 1949). 

Climate-Daily and annual 

temperature fluctuations are minor 

because of the influence of the surrounding ocean, yet, because of rugged terrain, sizeable geographic 

variations occur in rainfall, temper1- 0 - 75 meters 1-1 75 - 150 meters Lm] 150 - 300 meters ...... ......, .. .,., 

300 - 600 meters 600 meters and up 

Figure 1 -Major physzograph~c features of Puerto Rice [adapted from Hunt 19671 

2 
Figure 2.-Mean annual preczp~tatzon for Puerto Rico (ComrnonuteaLth of Puerto Rico 1979) 

ature, wind speed and direction 

over relatively short distances (Calvesbert 1970). 

The island receives an average of 

1800 millimeters per year of rainfall, mostly orographic. Coastal 

areas receive from 750 millimeters 

per year in the southwest, or leeward part of the island, to 1500- 

2000 millimeters per year in the 

northeast, east and southeast, or 

windward part of the island. Areas 

of heavy rainfall, in excess of 2500 

millimeters per year, include the 

summits of Luquillo, Carite, Toro 

Negro and hlaricao forests (figure 

2). A relatively dry season occurs 

over most of the island from midDecember through the end of 

March. 

The lowest mean annual temperature is 18 degrees centigrade at 

Pico del Este and Cerro Maravilla 

and the highest, 27 degrees centigrade at Guayama on the South 

coast. The highest temperature 

ever recorded was 39" centigrade at 

San Lorenzo in August 1906; the 

lowest 4 degrees centigrade at Aibonit0 in March 1911. 

Seasonal variation in cloudiness 

at stations on the north coast shows 

a maximum during May-June and 

September-October, with the lowest daily average during March. 

Convective buildups cause somewhat higher daytime cloudiness in 

the interior (Briscoe 1966). 

The easterly trades are one of the 

most constant wind regimes, generally blowing from the ENE through 

ESE. The highest mean wind speeds 

occur during July and the lightest 

during October and November. Factors which interrupt trade wind 

flow include frontal passages, 

easterly waves and tropical disturbances. 

Puerto Rico also experiences 

occasional hurricanes, most of 

which pass through the Caribbean 

in August and September. In 1898, 

1928,1932, and 1956, storms passed 

over the island. During the 1928 

storm, known locally as San Felipe, 

San Juan experienced winds 

around 260 kilometers per hour. 

Storms of this magnitude cause destruction of roadside trees and 

changes in forest composition and 

growth rates i Wadsworth 1959a, 

Crow 1980). 

Soils-Differences in rainfall 

patterns, as well as geologic and 

geomorphologic condition in Puerto 

Rico, have given rise to a wide variety of soils. Initially classified 

according to environmental and external factors such as climate and 

topography (Roberts et al. 19421, 

soils were recently reclassified in 

terms of soil morphology and composition (Beinroth 1971; LugoLopez and Rivera 1977). Under the 

new system, 9 of the 10 possible soil 

orders were recognized in Puerto 

Rico, although 6 of these together 

occupy only 15 percent of the island 

(fig. 3). 

The most extensive soils are Inceptisols, occupying about 37 percent of Puerto Rico. This order is 

concentrated in the eastern half of 

the island, generally on slopes ranging from 20 to 60 percent. Erosion, 

particularly in cultivated areas, 

prevents the development of mature profiles. 

Next in areal importance, occupying about 27 percent of the island, are Ultisols, concentrated in 

the humid volcanic uplands of the 

Western Cordillera. They are re- 
Intense storms cause erosion and modify the 

forest. This landslide occurred in the Luquillo Mountains during the passing of hurricanes David and Frederick, 1979. 

stricted to humid climates, where 

they either occupy old surfaces or 

evolve in highly weathered alluvial 

sedimc-2nis. 

'it.lollisois, occupying 21 percent of 

the island, occur in 3 areas: tertiary 

limestones near Lares, southern 

foothills in the rainshadow of the 

Cordillera, and scattered alluvial 

fans and floodplains. MolIisols have 

a dark colored surface horizon of 

considerable thickness, high in 

base saturation and organic matter. 

For the purposes of plantation 

establishment, 19 soil associations 

were recognized on the island (Zambrana 1978). Tree species for wood 

production, windbreaks, shade and 

ornamentals were suggested according to soil association. For the 

purposes of this inventory, only four 

classes of soils were distinguished: 

deep volcanic soils, shallow volcanic soils, granitic soils, and limestone 

soils. More detailed studies of 

vegetation on the island need a 

more refined soil classification 

system. 

10 20 30 40 km 

SOIL ORDER 

MOLLISOLS 21.3 

. 13 lNCEPTlSOLS 36.7 OXISOLS 3.8 

-- /* 

-. . -.. _ _- -*- - 

Flgu_r, ' GGaltzed sozl map of Puerto Rrco r Bernroth 1971 1 
Population and Land UseTaino Indians, island occupants at 

the time of the 16th century conquest, either died or were driven 

away {Puerto Rico Public Affairs 

Administration 19791. Since then 

there has been a steady immigration of people from all over the 

world. Recently, Cubans and Dominicans have arrived, as well as a 

continual migration of Puerto 

Ricans back and forth from the U.S. 

mainland. The island's population 

reached 1 million at the turn of the 

20th century, passed 2 million about 1945, and currently stands at 

over 3 million, or about 400 people 

per square kilometer (over 1000 per 

square mile). 

During the 1920's and 1930's) two 

hurricanes and the depression 

brought a large part of the predominantly rural population to the brink 

of starvation. At that time, sugar 

was the dominant cash crop and 

accounted for two-thirds of the island's exports (Barton 1959). The 

decision in the 1940's to invest in 

other income-generating and financially self-supporting programs, including public utitilities and an industrial development company, 

paved the way for expansion of the 

island's industry. 

Land clearing for agriculture resulted in the deforestation of all but 

3400 hectares, including some 2200 

hectares in the Luquillo Mountains 

and lesser areas in Carite, Toro 

Negro, Guilarte, Maricao and a few 

scattered peaks in private ownership (Wadsworth 1950). Only in 

these isolated areas can remnants 

of the island's climax vegetation be 

found. The remaining forested 

areas are secondary, arising from 

abandoned coffee shade, pastures or 

croplands. 

In the comprehensive 1972 land 

use survey conducted by the Department of Natural Resources 

(table I), over 50 percent of the island is classified in agricultural 

uses, about 30 percent in forests including public and private, about 5 

percent water resources, and some 7 

percent as urban and rural residen- 

-- -" 

Table I.-Summary of land use rn Puerto Rer- :972' -- _ - '-._ 

Land use 

Agriculture 

Forests 

Water resources 

Wetlands 

Son-productive areas 

Resldent~al 

Outdoor recreation 

Public use 

Commercial use 

Industrial use 

Mining 

Communications 

Transportation 

- - +, - -- hectares * -'1 

376,000 ?&xed agriculture, rnonocuiture. inactit e areas 

264,800 Dense forest, secondary forest, public forest 

Canals, protected coastal waters, lagoons 

Mangroves and swamps 

Rocky areas, reefs, coastal sandy areas 

High, medium and low density, urban and rural 

All types -. 

All types 

Hotels and commercial centers 

Light and heaw ~ndustry; industrial parks 

Sand and gravel extraction; salt and minerals 

Generating plants, substations; antennae 

Airports; port fac~littes; roads 

'Data summarized from Department of Natural Resources Inventory, 1972. 

'Does not agree with total used elsewhere due to inclusion of coastal waters, reefs, etc. 

tial areas. The agricultural classification includes coffee shade. 

Description of the 

Forests 

Many descriptions of Puerto 

Rico's forests are available 

(Gleason and Cook 1926; Cook and 

Gleason 1928; Beard 1944, 1955; 

Stehle 1945; Ewel and Whitmore 

1973). Some emphasize the forest 

formations in the Luquillo Mountains (Wadsworth 1951; Dansereau 

1966). 

Vegebtion Classification and 

Forest Associations-The most 

recent classification of the vegetation of Puerto Rico (Ewel and Whitmore 1973) uses the Life Zone system (Holdridge 1947, 19671, which, 

among other benefits, provides a 

means of comparison among tropicForestry and agriculture In the Toro ~Vegro 

Forest Reserue durlng the mld-1960's (photo 

by Wadsworth 1. 
a1 forests based on climatic data. 

The Subtropical Moist Forest occupies the largest area, covering over 

58 percent of the island (fig. 4). Next 

in importance is the Subtropical 

Wet Forest covering about 23 percent, and the Subtropical Dry 

Forest occupying about 18 percent 

of the island. The last three Life 

Zones occurring on the island 

account for a little over 1 percent of 

the land area. 

The Subtropical Dry Forest receives from 600- 1100 millimeters of 

rainfall per year and is characterized by deciduous vegetation. 

Leaves are often small and succulent or coriaceous, and spines or 

thorns are common. Tree heights on 

zonal soils do not exceed 15 meters 

and the crowns are typically broad 

and flattened with sparse foilage. 

Coppicing is common. Growth rates 

are slow in woody species, and the 

wood usually hard and durable. Extensive areas of Subtropical Dry 

Forest overlie limestone, and some 

low alluvial areas contain saline 

soils. I'vlangroves are found in coastal bays and inlets. 

The Subtropical Moist Forest receives from 1000-2200 millimeters 

of annual rainfall, and is characterized on zonal soils by trees up to 20 

meters tall with rounded crowns. 

Many of the woody species are deciduous during the dry season, and 

epiphytes are common. Grasses, 

both in natural and improved pastures, form the dominant landscape 

in the Life Zone today. The limestone hills on the north coast have a 

catena of associations which correspond to a moisture gradientmoist on the gentle north slopes, 

more humid still on the steep southwest slopes, and xeric on the summits. Stem density is greater in this 

-association. and stem size smaller. 

The serpentine-derived soils, found 

in southwestern Puerto Rico, support a unique vegetation which contains a number of endemics. Trees 

are commonly slender and under 12 

Subtropical Dry Forest in the vicinity of the 

Guanica Forest Reserue iphoto by Wadsworth). 

et al. 1970). Mangroves are also ceives more than 3800 millimeters 

found along the coast where they of rainfall per year, which leaves 

appear to grow taller than in the the soil at the field capacity 

Subtropical Dry Forest. Just inland throughout the year. Runoff is profrom the mangroves are alluvial duced every month. The species in 

soils that once supported an im- this Life Zone are the same, generpressive forest. Remnants of swamp 

forests dominated by Pterocarpus 

officinalis are evident today near 

Humacao, Dorado, Vacia Talega, 

and La Boquilla north of Mayaguez. 

The Subtropical Wet Forest receives from 2000-4000 millimeters 

of annual rainfall, and soil moisture 

drops below field capacity for only 3 

months during the year. Runoff is 

substantial. On zonal soils, the 

forest is impressive, containing 

more than 150 species of trees and 

forming a dark canopy at about 20 

meters. The abundant moisture is 

evident in the character of the vegetation; epiphytic ferns, bromeliads 

and orchids are common. Serpentine areas are also found, and in 

contrast to those in Subtropical 

Moist Forest, the vegetation is 

greener, denser, more lush, and contains more epiphytes. Where limesto~e is the parent material for 

meters tall. Most of the species are. sods, the vegetation is more ACrLUj phOtwruph Of iimelonr hLlis ,2m,- 

sclerophgllous and evergreen, and xerophytic than the zonal soil areas. c,,i,, by Purrto R~~~ Deporfnieni of 

species diversity is high (Tschirley The SubtrF;pco! Ram Forest re- P~~LC Works, 
GUAJATACA 

Figure 4.-L~fe Zones of Puerto Rico and location of public forests {adapted from Eroel and Whitmore 19731. 

% AREA LIFE ZONE 

ally, as those in the surrounding 

Subtropical Wet Forest. The high 

frequency of palm (Prestoea montanai and abundance of epiphytes 

are the main features which distinguish this Life Zone. All vegeta17.6 

58.4 

22.6 

0.1 

1.2 

0.1 

100.0 

tion is situated on clay soils. 

The Lower Montane Wet Forest 

occurs in both the eastern and central part of the island, extending 

from about 700 meters through the 

summits of most peaks above 1000 

meters. The mature vegetation is 

characterized by open-crowned 

trees, many with leaves grouped toward the ends of branches. The 

leaves are coriaceous and dark, giving the canopy a reddish cast. Three 

additional associations commonly 

appear within this Life Zone. The 

elfin woodland is characterized by 

gnarled trees less than 7 meters 

tall, high basal area, small diameters, high stem density, and slow 

n SUBTROPICAL DRY FOREST 

] SUBTROPICAL MOIST FOREST 

SUBTROPICAL WET FOREST 

SUBTROPICAL RAlN FOREST 

a LOWER MONTANE WET FOREST 

LOWER MONTANE RAIN FOREST 

growth. trees are evergreen and Tvpieal landscape rn the Subtropical Moist 

sclero~h~llous~ with leaves group- Forest L~fe Zone showing improved pasture, 

ing at branch ends. Decomposition ldle farmland, and scattered trees. 
is slow, and subsurface soils are 

clayey and oxygen deficient. The 

~afm brake, consisting of nearly 1 

pure stands of Prestoea montana, is 

found in this Life Zone, as well as 

the Subtropical Wet and Rain 

Forests. Finally, in the Maricao 

forest in the western Cordillera, 

serpentine soils are found. Species 

diversity is high and numerous endemic species occur Weaver 1979). 

The Lower Montane Rain Forest 

has vegetation similar to that of the 

Lower Montane Wet Forest, but 

epiphytes, palms and tree ferns are 

more abundant. The elfin woodland 

is the principal association, frequently found on windswept ridges. 

Stems are gnarled, laden with 

epiphytes and soil surfaces are covered with liverworts and bromeliads. Both superficial roots and aerial roots abound. Growth rates are 

slow. 

Forest PIantations - Forest 

plantations have had a significant 

role in reforestation and research 

with exotic and native species. 

According to Forest Service records 

(USDA Forest Service, Annual Reports), about 11,200 hectares were 

planted by public agencies as of 

1978, while private interests have 

planted about 27,000 hectares. The 

overall success of these plantations 

and the current area of plantation 

forests are not known. The major 

species planted was Caribbean pine 

(Pinus caribaea Morelet) with 

mahogany (Swietenia rnacrophylla 

King and S. mahagoni Jacq.), 

eucalyptus (Eucalyptus robusta J. 

E. Smith), and teak (Tectona grandis L. f.) also accounting for significant areas. Numerous other tree 

species, tested in a long series of 

adaptability trials, account for the 

remainder of the planted area. 

Forest Resource 

Values 

Nurnerous benefits and uses are 

derived from forested lands. Among 

them are production of timber; control of water quantity and quality; 

wildlife protection; recreation; and 

research opportunities. Forest survey data must address issues defined by these values. 

Timber-Puerto Rico originally 

included more than 500 species of 

trees in 70 botanical families. These 

occurred in extensive and luxuriant 

forests of which only scattered relics 

may be found today. Data from the 

least disturbed of remaining stands 

suggest that the island contained 

about 195 million cubic meters of 

wood (Wadsworth 1950). Good timber species with large dimensions 

were once common stand components. Today, most of the original 

forest has been replaced by agricultural and other land uses, or 

secondary forest where agficulturai 

activities have been abandoned. 

Dendrological descriptions of the 

species, their areas of occurrence on 

the island, their natural ranges 

within the hemisphere, and their 

potential uses have been documented (Little and Wadsworth 

1964; Little, Woodbury, and Wadsworth 1974). 

Mathre Subtropicczc \! ,7J F',~'~st 1t2 the LuquiIlo iMountalrzs 
Sixty species have been classified 

as potential native and plantation 

sawtimbers i Longwood 1961 I, many 

of which are found elsewhere in the 

Caribbean t Longwood 19621. A recent survey of native species. using 

size and wood characteristics as 

selection criteria, determined that 

the best use of 31 species was fbr 

cabinet woods, 8'7 as novelty woods, 

and 127 for roundwood. The remaining half of the island's tree species 

have little economic value except 

locally for fuel or fence posts. In the 

Subtropical Wet Forest of the Luquillo Mountains, some stands have 

been managed to enhance growth, 

improve species composition, and to 

increase the uniformity of tree size 

to sustain the yield of forest products (hfunoz 1968). Nearly 70 percent of the stems tallied in a 1962 

inventory were commercially important (table 11). Basal area averaged about 16.5 square meters per 

hectare, with volume approaching 

85 cubic meters per hectare, and net 

annual volume increment exceedifig 3 cubic meters per hectare. 

Other studies ofsimilar stands have 

shown that ff,,!sal areas of about 20 

square meters per hectare indicate 

vigorous stand conditions and saeisfactory growth rates. In contrast to 

these managed secondary stands, 

basal areas in virgin Subtropical 

Moist Forests range from 35 to !5Q 

square meters per hectare. Volumes 

range from 210420 cubic meters 

per hectare, and net annual volume 

increments are between 1.7 and 3.5 

cubic meters per hectare. 

Long-term diameter increment 

has been summarized for variously 

located stands, ranging from mangrove forest on the coast through 

Subtropical Wet Forest and Lower 

Montane Rain Forest in the Luqui110 Mountains to Subtropical Dry 

Forest in the southwest (Crow and 

Weaver 1977; Weaver 1979). These 

studies showed that significant differences in growth were found 

among species and crown classes, 

with the maj~rity of stems paralleling growth rates in temperate zone 

forests. Diameter increment also 

varied by life zone, with the slowest 

rate in the Subtropical Dry Forest, 

and the most rapid rates in secondary Subtropical Moist Forest including mangroves and an association on zonal soils. 

Mangroves-&fangroves extend 

to 29-30 degrees latitude in both 

hemispheres and cover from 60-70 

percent of the shoreline within the 

tropics. Their best development 

occurs within 23 degrees of the 

equator along protected shores. 

Mangroves have provided local 

wood products in the past; however, 

the area has declined dramatically 

and mangroves are no longer heavily exploited for timber. Mangroves 

have important non-timber values 

and their special significance is 

briefly outlined here. 

hlangroves provide shoreline protection by stabilizing soils against 

the pounding of waves and tidal 

A trad through the cloiid ;brei.t firmation 

(elfin woodland) In the higizer elet ation* of 

the Luqu~lLo ,Mountatns 
movements. They also support a 

myriad of fauna both as a substrate 

and - e through export of organic matter,P,*Paerto Rico. they protect rare 

and endangered bird species and 

serve as spawning areas for fish. 

Elsewhere, their high specific gravities, about 1 .O, provide fuelwood 

with a high caloric content. Some 

species also yield tannins for the 

curing of leather. 

Four species of mangroves r red, 

black, white, and button) may have 

once covered about 24,000 hectares 

in Puerto Rico (Wadsworth 1968). 

Mangrove coverage was reduced to 

6400 hectares by exploitation for 

fuel and wood during the Spanish 

period, a series of destructive hurricanes from 1825-1891, reclamation 

of mangrove areas for agriculture 

during the early 20th century by 

the sugar industry, and extremely 

destructive hurricanes in 1928 and 

1932 tcarrera 1975; Martinez et al. 

1979). By 1959, an increase in mangrove area to about 7200 hectares 

was observed [Wadsworth 1959a), 

the result of decreased cutting for 

fuel and recovery after hurricane 

damage. In the 1960's, urban development and industrialization 

caused new destruction. By 1968,13 

of 62 estuarine zones had been destroyed, and mangrove coverage declined to 6600 hectares. In 1979, a 

study of 18 mangrove areas provided an estimate of 5970 hectares 

for mangrove coverage (Martinez et 

al. 1979). 

Several different types of mangrove forest are recognized in Puerto Rico including overwash, fringe, 

basin, riverine and dwarf (Lug0 and 

Snedaker 19'741. All are dependent 

upon topographic variation and differences in flushing, and exhibit 

distinct species compositions, structure and patterns of productivity. 

Rapid diameter increments in 

secondary basin mangroves were 

observed i Weaver 19793 and annual 

volume production was estimated 

at 8.5 cubic meters per hectare 

high erosion potential, and rapid 

clearing and development of land 

for agriculture and other uses 

causes major erosion and sedimentation problems. The island's 

high population density and agriculturally-based economy during 

the 19th and early 20th centuries 

disturbed over 99 percent of the original forests, leaving only scattered 

areas of climax vegetation in the 

Central Cordillera and Luquillo 

Mountains t Wadsworth 1950 r. Concern for watershed protection 

prompted incorporation of tracts 

into the public forests of Toro Negro, 

Table I1 -lntentot?, of Subtropical Wet Forest in Luqurllo Expertrne~zi Forest Puerto R,co 

1962' 

Xiensuration statistic Furniture - - - - 

No stems~ha. 

17 5-24.9 cm dbhi 4 1 148 22 1 410 1'72 582 

(25+ cm dbhi 13 13 - - -- 

Total 54 161 22 1 

Basal area (m'lhai 

(7 5-24 9 cm dbh) 0 87 2.55 3.47 6 89 2 75 9 64 

(25 + cm dbh) 1 79 1.19 . . -2 98 - 3 86 6 84 _-- - - - 

Total 2 66 3.74 3 47 9 87 661 1645 

Volume (m3ihar 

17 5-24 9 cm.dbh) 3 71 11.31 1449 29 51 11 91 41 42 

(25 + cm.dbh) 12 49 6 49 . . 18 98 24 45 43 43 ----- 

Total 16.20 17 80 14.49 48 49 36 36 84 85 

'Adapted from Munoz 1968. 

f Wadsworth 1959b9. 

Water and Erosion Sawn lumber of tabonuco, Dacryodes excelSteep topography, heavy rainfall s,, ready at the road for shrprnrnt near V"'llaiand erodable soils contribute to a ba (photo by Wadsworth, 1945). 
The mangrove forest adjacent to the Sun 

Juan metropolitan region is visible in this 

high altitude color infrared photograph. 

Carite, Maricao, Susua, Ria Abajo, 

Guajataca and Guilarte from 1935 

through 1943. The first 3 of these 

areas, with about 2500 millimeters 

of annual rainfall at the summits, 

and the Luquillo Forest, which receives over 4000 millimeters per 

year at the summits (Weaver 1972), 

total about 35,000 hectares in these 

critical watershed areas. The major 

streams originate in the Central 

Cordillera, and only 7 have drainage areas in excess of 250 square 

kilometers t Department of Natural 

Resources 1974). The headwaters of 

these rivers supply most of the island's 25 major reservoir sites 

which yield water to meet domestic, 

industrial. and agricultural demands. 

Investigations of 7 of the reservoir sites showed that from 4 to 90 

percent of the storage capacities 

had been lost through sedimentation Department of Natural Resources 1974!, the higher figure for 

the Ch-nerio and Coamo reservoirs. 

Another, Guayabal, lost 50 percent 

of its capacity from 1913 to 1958. 

The crest height was then raised 5 

Urban development reduces the area of this 

valuable resource each year (photo by 

NASA I. 

meters, but no action was taken 

within the watershed to curtail erosion (Bogart, Arnow and Crooks 

1964). Studies conducted by the 

USDA Soil Conservation Service 

( 1968) showed that 48 percent of the 

land had severe erosion problems 

and 22 percent had moderate erosion. 

Production and transport of sediments is affected by intensity and 

duration of storms (Greer 1971). In 

the Tanama River, the discharge of 

sediments for 1 day in 1968 was 70 

percent of the total for the year, due 

to heavy rainfall (Lugo, Quinones 

and Weaver, 1980). Other rivers in 

Puerto Rico show similar trends. 

Prolonged drought leading to water 

rationing and severe flooding are 

recurrent problems on the island. 

Sedimentation of reefs and mangroves has damaged these coastal 

systems. 

Unpublished statistics from the 

Institute of Tropical Forestry indicate that 445,000 hectares on the 

island should remain forested. 

These include areas with slopes 

greater than 40 percent, areas 

which are principal sources of water, areas unsuitable for other 

crops, and those adjacent to reservoirs. 

Rare and Endangered Plant 

Species-The diversity of habitats 

has led to the establishment or 

evolution of many plant species on 

the island. However, the limited 

size of the land mass combined with 

rampant destruction of large areas 

for agriculture and other uses has 

decreased some species to dangerous rarity. Over 500 species of endemic and non-endemic plants, many 

in Commonwealth and Federal Forests, have been classified as rare, 

endangered, or poorly distributed 

(USDA Soil Conservation Service 

and Commonwealth Department of 

Natural Resources 1975). According to a recent Forest Service report 

(Little and Woodbury 19801, 13 rare 

endemic tree species are classed as 

endangered, and 22 endemic tree 

species are threatened with extinction, principally because of habitat 

destruction and disturbance. About 

100 tree species are listed as rare in 

Puerto Rico and the Virgin Islands, 
but are 1iste:- ,tive to other 

areas. 

Wildlife-Pue-L* ice's ~";;:~lve 

wildlife species are 1 irnited. ;,~SIdent native mammals include 15 

species of bats (Starrett 19621, and 

manatees and dolphins. Pigs and 

goats were introduced on Mona Island where they are feral, and deer 

on Culebra Island. The only other 

mammals of note are the mongoose 

and two species of rats. Of an estimated 200 bird species (Bond 1971, 

Leopold 19631, 14 are endemic, 107 

local breeders, 71 migrants, and 21 

strays. About 70 species of reptiles 

and amphibians are native to Puerto Rico (Rivero 1978) and 33 species 

of fresh water fish (Erdman 1972). 

The importance of the island's 

coastal, karst and montane forests 

in providing critical habitat for endemic species, as well as rare and 

endangered species is summarized 

in table 111. Puerto Rico currently 

has 27 species listed as very endangered, 29 species as endangered, and 15 species as on the verge 

of being endangered (USDA Soil 

Conservation Service and Commonwealth Department of Natural 

Resources 1973). Perhaps the Puerto Rican parrot best exemplifies a 

species dependent upon an island 

forest. During the early l90O7s, the 

species was common ranging from 

Arecibo to the southern part of 

Puerto Rico and east to the oflshore 

island of Vieques. By 1955, the 

population had dwindled to about 

200 birds, and by 1967 only 20 remained, all endemic to the montane 

forests of the Luquillo Mountains. 

Today, about 40 birds survive, 

mainly due to the efforts of the 

Forest Service and Fish and Wildlife Service. 

Other critical wildlife areas not 

included within the forest system 

are the Roosevelt Roads Navy Base 

and Mona and Monito Islands. The 

Navy Base has mangrove forest and 

freshwater swamp, which serve as 

critical habitat for 9 endangered 

bird species, and offshore Thallasia 

beds where the West Indian manatee has been seen repeatedly. 

Approximately half of the bird species of Puerto Rico are migratory 

visitors or residents on the base 

(Weaver, Nieves and Crow 1977). 

Mona Island, an elevated limestone block of 5,500 hectares, and 

adjacent Monito Island of 16 hectares, are located west of Puerto 

Rico about midway to the DominiRed Mangroue forest near Mayaguez, Puerto 

RLCO (photo by Cintroni. 

Watershed protection is a primary function of 

the Maricao Forest Reserve in the Central 

Cordillera. 

can Republic. Most of this scrub 

woodland serves as a refuge for 133 

species of plants and animals not 

found in Puerto Rico. In addition, at 

least another 29 species on the islands, including many sea birds, are 

so rare or endangered in Puerto 

Rico that Mona and Monito may be 

considered their last significant refuge (Junta de Calidad Ambiental 

1973). 

Recreation - Puerto Rico7s 

numerous beaches, coral reefs, 

waterfalls, canyons, scenic mountain roads, and limestone caves and 

cliffs, combined with year-round 

moderate weather, provide the 

basis for outdoor recreation, particularly in the well-distributed 

34,000 hectares of Federal and 

Commonwealth forests (table 111; 

fig. 2). Major activities include 

swimming, snorkeling, picnicking. 

boating, fishing, camping, hiking, 

water skiing, and driving through 

the forested areas. Any spot on the 

island is within an hour's drive of a 

major recreation area. Although 

some areas have excellent facilities, 

most are undeveloped (Department 

of Natural Resources 1974, 1976). 

Given t1re island's limited area and 
high popuiat:on denel- ;:be ex- . * isting fore>: -,:;stem .a1 resource for botr, resldt.,~~" xurists t Outdoor Recreationbi. .- r-ees 

Review Commission 1962 ).- 

Overview of Research-Puerto 

Rico's tropical forests have been a resonal focus for forestry and ecologca1 research throughout this century. 

The impact of this research extends 

far beyond the island itself. A few 

projects will illustrate the breadth of 

this research. 

The establishment of a tree 

nursery and the beginning of a 

large-scale research program of 

trial plantings with exotic and native tree species was begun in 1920. 

In 1934, a major reforestation program in public forests was initiated, 

and over the next 12 years, some 

7,800 hectares were planted with 53 

tree species, 28 of which were native. In 1939, the Tropical Forest 

Experiment Station (now the Institute of Tropical Forestry) was 

established and a site adaptability 

program was started in which more 

than 100 native species and over 

350 introduced species were tested. 

The mid-20's also brought American scientists into Puerto Rico to 

survey the natural forests (Gleason 

and Cook 1926; Cook and Gleason 

1928). In 11939, the first of 24 

volumes of the Caribbean Forester 

was published, covering both 

plantation forestry and investigation of natural forests. In 1952, the 

first island-wide forest inventory 

was undertaken by the Cornmonwealth Forest Service, and in 1972, 

the Commonwealth Department of 

Natural Resources initiated several 

research projects within the Commonwealth Forest Reserve, other 

forested areas, and the coastal zone. 

During the 1960's, several longterm studies of the climate, wildlife 

and vegetation of the Luquillo 

Mountains were initiated. Weather 

phenomena were documented and 

Endangered Puerto Rrcan Parrot In Loi~er 

,Ifonlane Wet Forest of the Luqu~llo 'Vfountams (photo by Wtleyj. 

compared with coastal sites in proximity to the mountains (Briscoe 

1966). The dwarf forest at the sum- 

"- was described in a series of 

arlic!es appearing in the Journal of 

the Arnold Arboretum from 1968 

through 1979, and the tabonuco 

forest at El Verde Field Station was 

investigated in detail (Odum and 

Pigeon 1970). Moreover, the colorado forest at intermediate elevations 

was studied in conjunction with the 

Puerto Rican parrot project, (Snyder 1978) which was begun in 1967. 

A record of forestry research and 

ecological investigations was recently compiled for U.S. Forest 

Service personnel in Puerto Rico 

t Lugo 19'791, and a bibliography of 

all forestry research on the island is 

anticipated.' Studies of plant ecology in Puerto Rico and elsewhere in 

the West Indies were also summarized t Rundel 1974). -. 

'Mosquera and F'eheley r in process). 
The Commonueaith Forest Reserr eh scat. 

tered throughout the ~siand proilde Lanous 

recreatton opportun~tles This IS the L\Ianiaci 

vzs~tor center 

Young, managed stands tn Subtroptcal Wet 

Forest (locally tabonuco forest) near the El 

Verde Field Statzon Ln the Luqutllo Mountains (photo by Wadsworthl. 
Table 111 of rccrea~z~fi and u ildlife r sin+ a J+ - ~re\tc, Pnerto Rtco, 1980 

Vegetd:~.. Forest ~rea E!evat~on Ld~d use and recreation 

8 ha) mi ~SSOCI~::CK-. ".* ;;.. - TLr i 

cc-,,4~rr~t FQRESTS 

9713 13-5 Siibtropical Dry Forest - Boating, fishlne, ptcnicklng; .~~quirre tidai flats and mangrove no faciiitres 

300 -5 Subtropical Dry Forest - Special use permits = 94 ha; BI qileron t~dal flats and mangrove, iwtmming, camping, hlk- 

-crub \+oodiand ing. ptcnicking, fishing, sailing, water skiing: cabins 

110 0-5 Subtropical Dry Forest - Boating Ceiba qait flats and mangrove 

Cuanica ~3880 0-228 Subtropical Dry Forest - Picnicking, swimming, hikmangrove; diverse scrub ing, beach facilities 

woodland; Flora - 48 endangered plant species, 16 

endemic to forest 

Pi nones 0-1 Subtropical Moist Forest - Special use permits= 12 ha; 

mangrove; beach strand swimming. picniclung, snorkeling, boating, fishing, water 

sluing; clandestine facilities 

LVlidiife assets 

60 bird specles, 3 endemic 

78 fish species; 50 b~rd species. 

some endangered C* 

Manatee habitat offshore 

Half of the island's land bird species; breeding ground for endangered whippoorwill 

38 fish species; 46 bird species, 

some endangered: phosphorescent lagoon 

KARST FCiRESTS 

Carnbalache 370 5-50 Subtropical Moist Forest - Special use permlts=6 ha; 45 btrd specles, d endemic to 

xeric forest on pepino hlll some hlk~ng, p~cnlcklng; no tsland; endemtc tree frog 

bottomlands, slopes and facilities 

summits 

930 130-300 Subtropical Motst Forest - Special use permits=3 ha; 35 bird species, 8 endemic to isassociations as above some hiking, picnicking; land 

limited facilities 

RIO Abajo 2270 200-424 Most Subtropical Wet Forest Speclal use permits = 34 ha; Probably similar to above 

Some Subtropical Pifoist Forest picnicking, camping 

350 5-50 Subtropical Moist Forest - Special use permits = 56 ha; Probably similar to above 

associations as above some hiking, picnicking; 

limited facilities 

SfCtNTAAN E FORESTS 

C',xrlte 2620 250-903 Most Subtrop~cal Wet Forest 

Small Lower Montane !Vet 

Forest - (tabonuco, colorado, palm, dwarf, early 

secondary 1 

?vI~r~cao 4150 15-675 Most Subtropical Wet Forest 

Small Subtroptcal SIoist 

Forest 

Small Lower Montane Wet 

Forest - assoctations as 

above; Flora - 845 specles, 

278 trees, with 123 endemic 

to Island and 20 to 5Iartcao 

Special use permits=42 ha; 30 bird species, 9 endemic, 2 

critical watershed; picnick- hawks; Lake Carite good bass 

ing, hiking; recreation fa- lake 

cilities 

Special use permits = 32 ha; 26 bird species, 16 breeding resicritical watershed; hiking, dents, 11 species endemic to ispicnicking; cabins - facili- land 

ties 
Life Zone. Ldnt: : s rpi:redti3n tVlldlife aksets 

s, unique flora - g 

Guilarte 1420 760-1205 Subtropical Wet Forest Specla1 use permits = 75 ha, Probably similar to above 

Lower Montane Wet Forest - crit~cai watershed; no facilassociations as above i ties 

Sulsua 1310 . 80-473 Subtropical Molst Forest - Special ust. pernuti= 12 ha. 

dry slope and gallery asso- uatet-shed Importance, some 

ciations, secondary forest, Ereation facilittes 

Flora - numerous endemic 

plants 

Tbro Negro 2730 440-1338 Subtropical Wet Forest Special use permits = 38 ha: Probably similar to above 

Lower Montane Wet Forest - critical watershed recrea- 

(tabonuco, colorado, palm, tion facllitles 

dwarf, early secondary) 

Luquillo 11300 120-1060 Subtropical Moist Forest 203 special use permits; criti- 25 bird species, some endemic; 

Subtrop~cal Wet Forest cal watershed; hiking, pic- endemic lizards, frogs, snakes 

Subtropical Rain Forest nicking; Visitor Informa- endangered Puerto Rlcan ParLower Montane Wet Forest tion Center, good facilit~es rot 

Lower Montane Ram Forest 

- associations as above -- - -- - 

Source: Department of Natural Resources 1974, 1976; Odum and Pigeon 1970. 

PREVIOUS FOREST SURVEYS AND ESTIMATES 

At the beginning of the 16th century, Puerto Rico was covered with 

mature forests containing a great 

variety of species with high quality 

timber. The forest formations were 

typical of the Caribbean region at 

the time of discovery (Little et al. 

1974, Durland 1929). 

In subsequent years, European 

settlers gradually cut the coastal 

and lowland forests for pasture or 

cropland. Removals for timber, 

charcoal, and fuelwood significantly modified the forest, but land 

clearing for agriculture was much 

- more destructive. By 1828 257,000 

hectares of pasture and 47,000 hectares of cultivated land represented 

34 percent of the total land area 

(Wadsworth 1950). 

Most remaining mature forests 

were removed in the 19th century as 

the population in~zased to nearly a 

million. By 189L3, pasture alone 

accounted for 55 percent of the land 1899). Many small farmers were 

area (Wadsworth 1950). The best successful only by practicing a sys-- 

agricultural land was held by large tern of shifting cultivation known as 

export-oriented farms, and about "conuco". When coffee became a ma22,000 small subsistence farms jor crop, Puerto Rico's natural 

were scattered on the hillsides (Hill forests declined further. Coffee was 

Table 1V.-H~stor~cal est~mates of forest area for Puerto R~co - - -- - - --- - - - 

Year of Forested area' Coffee shade Source of information 

estimate ---- -- - - - 

- - 

ca. 1500 

1828 

1899 

1912 

1916 

1931 

1940 

1948 

1960 

1972 

'Does not include non-stocked forest land. 

Murphy, 1916, and Wadsworth, 1950 

Wadsworth, 1950 

Wadsworth. 1950 

Murphy, 1916 

Murphy. 1916 

G1l1 1931 

Koenig, 1953 

Koenlg, 1953 

Englerth. 1960 

Department of Natural Resources. 1972 -- 
grown under planted shade trees in 

the interior highlands where other 

cash crops proved unsuccessful. 

Early in the 20th century, forests 

covered about 20 percent of the island, but only about one-third of 

this forest land could yield wood 

products other than charcoal or 

fuelwood I Murphy 1916). Later, 

Puerto Rico Department of Agriculture figures showed half the island 

to be forest, brush, swamp, and barren land, containing little timber of 

any value (Durland 1929). Other 

estimates concluded that 80 percent 

of about 400,000 hectares of forest 

land was devastated. 

The rate of forest destruction declined during the first part of the 

20th century. Only the most remote 

and marginally productive lands 

remained uncultivated. During the 

ensuing decades, pressure on land 

resources came from many directions: increasing population, expanding production of export crops, 

and fluctuating economic conditions. During periods of high unemployment people were forced to subsistence agriculture, encroaching 

on the remaining lands in the interior. 

During the late 1940's the natural forest area of Puerto Rico declined to a minimum of 6 percent of carvzng fuelivood fi 

the land area i table IV). Cropland $~~~~~~~:~~st9 Garrot 

and pasture each accounted for about 42 percent, with the remaining 

10 percent in buildings, roads, and 

wasteland (Koenig 1953). Thus 

Puerto Rico became one of the most 

severe1y.deforested and eroded regions in the world. 

Recent statistics show that the 

forests have been returning in the 

past 30 years. Privately-owned 

lands have reverted to forest as 

small hillside farms were abandoned. These degraded lands, unsuitable for cultivation, support the 

potential forest resource assessed in 

this study. 

.Vouch ofRzo Patillas at Pat~llas lake shoi~ Eng 

extenszr8e delta due to eroslon upstream 1 photo 

by Wadsworth, 19.27) 

-om Carnbalache 

chales (photo by 
I-l'hrp sau Eng lumber of tabonuco. Dacryodes 

excelsa. Esplr~tu Santo Valley (photo by 

LZudsiborth, 1947) 

Accelerated gully eroston on Martcao Forest 

Reserve durzng the late 1940's (photo by 

Wadsworth). 

Forest removal and overgrazzng result zn serlous erosion. Locatton and date ofphoto unknown 
Deforested htllstdes durtng the rntd-1940's In 

the vzc~ntty of Mayaguez (photo by Wadsworth). 

Fuelwood prepared for making charcoal, Rio 

Grande (photo by Wadsworth, 194 7). 
THE 1980 FOREST RESOURCE SURVEY 

Survey Scope And 

Design 

Although previous comprehensive assessments of Puerto Rico's 

forests have been attempted, the 

1980 survey was the first by a Renewable Resources Evaluation 

Unit of the C'SDA Forest Service. 

The survey was designed to be responsive to local data needs. The 

primary objective was to assess the 

timber potential of the island. 

Fieldwork was concentrated in 

areas with commercial potential; 

other regions were assessed remotely or through literature research. 

Survey methods (see appendix) 

were designed to assess timber 

quality, volume, areal extent, and 

species composition. Physical site 

characteristics were also recorded. 

This information will address other 

current issues which include research on the management of secondary tropical forests, and monitoring secondary succession on tropical forest land. Subsequent surveys 

will assess changes in forest area, 

volume, and species composition. 

The island was partitioned geographically to allow focus on regions with commercial potential. 

Land uses excluding intensive timber production were delineated on a 

base map t fig. 5). This noncommercial survey region accounts for 

nearly 51 percent of Puerto Rico's 

area (table V). These areas include 

the agricultural regions of the 

northern coast and interior valleys, 

and the dry southern coast. The 

highest mountain regions were also 

eliminated because of watershed 

values or excessive rainfall or slope, 

Noncommercial survey regions 

were eliminated sequentially, beginning with the Subtropical Dry 

Forest Life Zone. Subsequent categories do not include areas already - 

eliminated in a previous category 

(fig. 5, table VI. 

The potential commercial forest 

region, more than 400,000 hectares, 

excludes environmental extremes 

and the better agricultural land. It 

is located in the dissected uplands 

between the fertile valleys and the 

highest, most rugged mountain 

areas. Annual rainfall varies from 

1000 to 2500 millimeters. The 

potential commercial region encompasses only 2 of the 6 Life Zones 

found in Puerto Rico. Broad soil 

associations reflecting geologic origin (table V, fig. 6) form the basis for 

stratification of the data. Soils of 

volcanic origin divided into deep 

0 10 20 30 40 50 km 

SUBTROPICAL DRY LIFE ZONE (5 1,000 MMlYR RAINFALL) 

EXCESSIVE RAINFALL (2 2,500 MMIYR) 

n EXCESSIVE SLOPE (2 60 O/O) 

a UNPRODUCTIVE SOILS 0 HIGHER PRIORITY USES 

0 COMMERCIAL SURVEY REGION 

Figure 5 -Excius~ons fi-om 1980 cornrnerc~al sur~ej regton Shaded areas uerr remo~ed sequent~ally fo deferm~ne the area fir field zncestlgat~on 

'Mangro~es, slcarnps, allu~tai flats, rnetropolrtan regtons 
Table V -1.o td area by survey region, Pnerto Rrco, 1980 and shallow clays, comprise 'iO per- . - -- - -- - - - - -- - - - 

. -6 - -- cent of the potential commercial 

Cnmrnerctai 

Subtropical SIo~st Forest Llfe Zone" 

Deep voican~c solis" 

Shallow volcanic 50113 

Granite soils 

L~mestone soils 

Total Subtropical Mo~st Forest Life Zone 

Subtropical Wet Forest Life Zone 

Deep volcanic soils 

Shallow volcanic soils 

Granite soils 

Limestone soils 

Total Subtropical Wet Forest Life Zone 

Total commercial 

NoncommercialJ 

Subtropical Dry Forest Life Zone 

Critical watersheds 

Unproductive soils 

Alluvial and metropolitan 

Mangrove and swamp 

Noncontiguous Puerto Rico 

Total noncommercial 

Total land area ___-_ ------- __ - - - - - -- 

Area 

hectares 

area. The deep clays include the 

typical deep red latosols found in 

the tropics. Granitic intrusions, 

about 10 percent of the area, result 

in a sandier soil in the uplands. 

Limestone soil supports a unique 

forest vegetation and accounts for 

20 percent of the potential commrcia1 region. 

Ecological Life Zone and soil 

group are important parameters 

which, along with previous land 

use, topography, and other site factors, determine forest resource 

characteristics. These classifications are interrelated. For example, 

coffee is generally grown in high 

rainfall areas (Subtropical Wet 

Forest) on deep volcanic clay soils. 

Life Zone and soil group yielded the 

most important prior knowledge of 

the survey region. Forest area statistics were compiled using this 

stratification rather than the county-based system used in the U.S. 

' Life Zones according to Holdridge (1967), determined by Ewe1 and Whitmore 11973). 

'Soil groups defined and mapped by Zambrana (1978). 

.%reas were defined sequentially in the order presented. Forest Ownership 

The largest forested areas in pubThe untque Cartbbean Nutzonal Forest 

attracts more than a rntllron cts~tors each 

year, and supplres most of the water used tn 

~Vortheastern Puerto Rlco. 

- 

lit ownership are the Commonwealth forest system, the Caribbean National Forest, Mona Island, 

and Roosevelt Roads Navy Base. 

The Department of Natural Resources of Puerto Rico also holds 

several areas of smaller extent. The 

remaining forest lands, about 85 

percent, are privately owned (table 

VI) . 

The Commonwealth forest system includes 14 forests scattered 

throughout the island. The Caribbean National Forest covers most of 

the Luquillo Mountains in the 

northeastern part of the island. 

Tbgether the public forests protect 

valuable soil and water resources, 

wildlife habitat, and many rare tree 

species. They also provide recreation and research opportunities in 

all the major natural ecosystems 

found on the island. These areas include nearly all of the remaining 

virgin forests. 
SUBTROPICAL 

LIFE ZONES: 

WET MOIST 

DEEP VOLCANIC SOILS 

SHALLOW VOLCANIC SOILS 

GRANITIC SOILS 

LlMESTONE SOILS 

Figure 6.-Life Zones and soil groups in the potential commercial forest region, 1980 

Forest ~rea~ 

Puerto Rico's 890,000 hectares of 

land include 279,000 hectares of 

forest land.3 Nonforest land uses 

account for 69 percent of the total 

land area. Land classed as timberland amounts to 15 percent of all 

land. Most of the timberland is located in the western highlands in 

and around coffee growing and pasture regions. 

Forest Land Increasing-Long 

term trends (table IV) show that 

forest area has been increasing in 

the past 30 years4 Most of the forest 

- - 

-%efer to appendix tables for this and all 

subsequent analys~s Some information 

screened from the data is only available 

through special processing 

'The definitions of terms are an integral part 

of a forest survey Users of the data in this 

report are advised to study the definitions 

presented In the appendix 

4Direct comparison of forest area between 

thls survey and previous ones is not reliable 

because of definition changes 

land classed as timberland is composed of young forests. If these 

trends continue, it may be possible 

to develop small scale forest products industries based on managed 

secondary forests. Commercial timber removals have not been important recently, and the island satisfies most timber needs through imports (Wadsworth 1971 1. 

Non-timber forest resource uses 

are currently more important than 

timber in Puerto Rico, as indicated 

by the large amounts of forest land 

in the noncommercial survey region. More than 16 percent of the 

land area is covered with forests 

whose primary use is for watershed 

protection, recreation, and wildlife 

habitat. 

About one-quarter of this important noncommercial forest lsnd is 

under public ownership and protection. Privately-owned noncommercial forest land includes many critical watershed and habitat areas 

which are best conserved under continuous vegetative cover. Most of 

the timberland is also privately 

owned. Although little is known of 

these owners, they ultimately will 

determine any future timber production on the island. Timber harvesting on noncommercial forest 

land could also help support small 

forest industries, but other values, 

marginal timber productivity, or 

ecological hazards reduce the 

potential contribution of this wood 

source. 

Timberland Increases Follow Retirement of Agricultural Land-About 54 percent of 

Puerto Rice's timberland has resulted from abandonment of pasture and cropland. The remaining 

46 percent of the timberland has 

been, or is currently, managed as 

coffee shade. Nearly 12,000 hectares of timberland are nonstocked 

with trees. Much of this land is covered with brush or o~ner inhibleing vegetation. 

Coffee production has been aban- * 
Cclrnmonweaith krests 

Commonweaith ,siandsl 

Department of Nat'cirai 

Resources' 

National forest 

U S ?llsistary 

Total public 

Area Source of :nformatlon 

12,11113 Department of Satural Resources. 1976 

5.500 .Junta cie Caliciad Amblental. 1973 

2,000 Rusanowsky, 1978 

11,300 hlunoz, 1968 

1,900 C' S Fish and W~idlife Service. I978 

43,400 

Private: 

Total pr~vate 235,300 

"Ions and Monito ~slands. 

"ands previously purchased by the Conservatton Trust were turned over to the Department of 

Natural Resources in 1981. 

doned on 38,000 hectares of timberland. These forests characteristical- 

' ly have low stocking levels and 

numerous large, poor quality trees. 

The shade trees currently used on 

more than 21.000 hectares of coffee 

land could have an important contribution to the timber resource; 

however, timber production as complementary to coffee production is 

not currently practiced. 

Timberland is about evenly divided among sawtimber-size, poletimber-size, and sapling-seedling 

stands. More than half of the 

timberland classed as sawtirnber 

has a basal area less than 15 square 

meters per hectare. These poorly 

stocked stands reflect the presence 

of numerous open-grown trees, 

Some of the older abandoned coffee 

shade stands have basal areas of 15 

to %O square meters per hectare. 

Poletimber stands are considerably better stocked, including 

29,000 hectares with 10 to 20 square 

meters per hectare basal area, and 

10,000 hectares with more than 20 

square meters per hectare. This 

most extensive stand-size class is a 

promising area for management 

practices which would favor the 

most desirable species. 

Sapling-seedling stands are not 

common in coffee shade. In contrast, 

some young secondary stands are 

highly overstocked, especially in 

the limestone hills, where site conditions favor smaller tree sizes. 

Low stand volumes are common 

in Puerto Rico's timberland. Seventy percent of the secondary forest 

land has less than 50 cubic meters 

per hectare of timber volume, significantly lower than managed secondary stands in the Luquillo Nlountains. Abandoned coffee shade 

stand volumes are mostly in the 25- 

75 cubic meter range, with only 

small areas in high and low volume 

classes. Active coffee shade, if properly managed, seldom carries more 

than 50 cubic meters per hectare of 

timber volume. Only older secondary forests and a few abandoned 

coffee shade areas have more than 

100 cubic meters of timber per hectare. 

Low basal areas and timber 

volumes are typical in both active 

and abandoned coffee shade, and in 

the younger secondary forests. 

These conditions also reflect the 

generally poor site quality which 

has resulted from intensive land 

use. 

&Most Timberland in Rugged 

Mountain Areashlost stocked 

timberland occurs in areas with 

rough topography. About 60 percent of the area has slopes greater 

than 45 percent. These hillsides, 

subject to severe erosion in the absence of continuous vegetative cover, 

are made difficult to farm by the 

unfavorable working conditions. 

The land quickly becomes unproductive when cultivated. 

More timberland is found on deep 

volcanic soils in the Subtropical 

Wet Forest Life Zone than in any 

other stratum. This is the most irnportant coffee producing region:' 

Two important forested soil groups 

in the Subtropical Moist Forest Life 

Zone are the shallow volcanic soils 

and the limestone soils. These strata include extensive pasture mixed 

among the forests. Timberland 

found on granitic soils is about 

evenly split between the two Life 

Zones included in the commercial 

survey area. 

Timber stands on deep volcanic 

soils have characteristics similar to 

coffee shade forests: low timber 

volumes in sawtimber-size and 

poletimber-size stands, few saplingseedling stands, a~d low basal 

areas. About two-thirds of the area 

was abandoned less than 30 years 

ago. Nearly 28,000 hectares of 

timberland on deep volcanic soils 

were classed as poletimber. 

Timberland on shallow volcanic 

soils is stocked with sawtimber-size 

or sapling-seedling stands, with 

only a small area of poletimber. The 

sawtirnber stands are mostly 

associated with coffee shade, while 

sapling-seedling stands tend to cover the more recently abandoned 

pasture and cropland. 

Sapling-seedling stands dominate the timberland in the limestone hills region. Coffee shade is 

essentially absent. Unusual soil 

and topographic conditions are responsible for much of the land remaining forested with small timber, despite evenly distributed 

stand ages, ?ample plots fall either 

in stands with very little slope, or 

stands with more than 45 percent 

slope. These plots correspond to the 

sawtimber-size and sapling-seedling stands, respectively. A narrow 

band of sawtimber is often found on 

the concave lower slopes and bottomlands of the limestone hills. 
Coffee is grown under shade trees which are a 

potential source of timber. 

Ahandorzed coffee shade results zn o mutiire 

0.i "2-r shade trees and young saphngs. 

Recently abandoned pasture and cropland is 

often rapidly overgrown with ferns or brush. 

delaying establishment of a forest stand. 
Granitic soils support~~~re uniformystand-size distrlburk 9-yith a 

substantial area of ;(i;z:.sri 7ber. 

These young stands are-ppk- fslly 

the result of abandonment 9.r: pasture and cropland. 

Dangerous precipices, steep 

ravines, numerous boulders and 

other obstacles, and a generally uneven land surface characterize the 

eroded slopes on all soil groups. This 

rugged, marginal land should be 

carefully managed for its timber 

potential. Even the partial cover 

provided by coffee shade may not 

result in sufficient protection from 

weather extremes, as heavy rains 

recurrently inflict heavy soil losses. 

Species Composition 

There are 547 tree species known 

to be native to Puerto Rico, with an 

additional 203 species naturalized 

(Little et al. 1974). This approximates the number of native and 

naturalized species found in the 

continental United States t Little 

1979). Such a striking richness 

of tree flora within a small area is 

an important consideration in an 

assessment of Puerto Rico's forests. 

Species Represent Past Human Influence-Two factors influence the current species composition of Puerto Rico's timberland. 

First, most of the timberland has 

been farmed or cleared for coffee in 

the recent past. Second, a wide variety of site conditions exist on the 

island. 

Field crews tallied 189 different 

species and were able to identify 

more than 99 percent of the sample 

trees. Ten species account for 49 

percent of the basal area (fig. 7). 

Many species were encountered 

very infrequently: 142 species together account for 16 percent of the 

basal area. 

The current forests are substantially different from the original 

vegetation. Nine of the ten most 

common timberland species are 

used for coffee shade, fruit, or ornament (table VII). Four of the five 

Table V1I.-The most common trees and thetr characterzst~cs. Puerto R~co tlmberiand, 1980 

Species 

Csed for 

coffee 

shade 

Inga cera IVilld. X 

Guarea gurdonza t L. 1 Sleurner X 

Cecropza peitata L. 

Andtra tnermls IN Wrlght) DC X 

Inga fagtfol~a L.) Wllld. X 

Eugen~a jumbos L. 

Tabebuui heterophylla IDC.) Bntton 

Spathodea campanulata Beauv. 

.Mangzfera ~nd~ca L. 

Cztrus sinensss Osbeck 

Erythrzna poepplgrana t Walp.) 

O.F. Cook 

Dendropanax arboreus i L.) Decne. 

and Planch. 

D~dymopanax rnorototonc (Aubl.) 

Decne. and Planch. 

Coffea arabtca L. 

Ocotea leucoxylon (Sw.) Mez 

Prestoea montana t R. Grah.) 

Nichols. 

Calophyllum calaba L. 

Roystonea borznquena O.F. Cook 

Alchornea lat~folia Sw. 

Thoucnla strzata Radlk. 

Used for C=ea i'_: Csed for Potentla1 

fru~t or ornament fuel or timber 

product or shade posts only spec!esL -- --- - - 

'Based on past use in Puerto Ricoi or use elsewhere in the tropics for products other than 

specialty items. 

Tabinet quality. 

INGA VERA 

GUAREA GUlOONlA 

CECROPIA PELTATA 

ANOIRA INERMIS 

lNGk FAGlFOLfA 

EUGENIA JAMBOS 

TABEBUIA HETEROPHYLLA 

SPATHOOEA CAMPANU LATA 

MANGIFERA INOICA 

CITRUS SINENSIS 

179 OTHER SPECIES 

0 200 400 600 800 

THOUSAND SQUARE METERS 

Figure 7.-Basal area of the most common tree specLes, Puerto Rtco ttmberiand, 1980 
most common species are extensively planted for coffee shade, accounting for 30 percent of the basal area 

on timberland. Significantly, 6 of 

the '7 most common species are 

potential timber species and account for 38 percent of the basal area. 

hiany of the common species tallied are pioneers of abandoned cropland or pasture. These species regenerate freely and many have 

rapid early growth rates. Large 

trees of species used for timber in 

the past are only found in isolated 

patches of mature forest. Most large 

trees found today are old ornamentals or fruit trees. 

Some species occur with great frequency in the smaller diameter 

classes. These include 3 excellent 

timber species which can grow into 

larger size classes, Guarea guidonia, Andira inerrnis, and Tabebuia 

heteroph-ylla, and some species 

which are found only in the understory, such as Coffea arabica, 

Casearia guianensis, and Guettarda 

scabra. Common coffee shade trees 

(Inga spp. and fast growing secondary species, especially Cecropia 

peltata, are relatively scarce in the 

smaller diameter classes but common in intermediate classes. Large 

trees (diameter class 55 centimeters or more average only about 

2 per hectare, the most common 

being Guarea guidonia, Spathodea 

campanulata, Mangifera indica, 

Erythrina poeppigiana, and Spondias rnombin. Although some of 

these species can be used for wood 

products, the large, open grown 

trees common in Puerto Rico generally have poor form. 

Coffee Shade Forests Less 

Complex Than Secondary Forests-Abandoned coffee shade 

brests contain fewer than half the 

species found in other reforested 

areas. A smaller number of species 

accounts for a higher percentage of 

the basal area; the 10 most common 

species in secondary forests account 

Se~~eral forest types and rugged topography 

characterzze the wet lzmestone regzon of the 

RLO Abajo Forest Reserve. 

20 25 30 35 40 45 + 

DIAMETER CLASS (CM) 

for 3'7 percent of the total basal 

area, while accounting for 69 percent and 80 percent in abandoned U,gure 8 -Number of trees by tree ciass and dmrneter ciass, Puerto Rlco t~mberiand 2980 
forests are not far behind. Rough 

A uariety of species and a few older "wolf' 

trees are evident on this secondary forest 

land. 

and active coffee shade, respectively. Average basal area per hectare 

in active coffee shade is about 10 

square meters. 

Coffee shade forests are less complex because species used as shade 

trees now dominate the stand. Coffee has generally been grown on 

deep clay soils in the Subtropical 

Wet Forest Life Zone, a relatively 

uniform region compared to the site 

diversity of other reforested areas. 

Smaller diameter trees are less 

common in coffee shade forests. 

Cultivated shade trees occupy most 

of the growing space and account for 

the greater number of stems found 

in the middle and upper diameter 

classes. 

There are important species differences as well. More frequently 

encountered in secondary forests 

are the palms and two timber species, Tabebuia heterophylla and 

Calophy ltum calaba. Coffee shade 

forests include more coffee, fruit, 

ornamentals, and other planted 

trees. Inga uera and Cecropia peltata are common in all forest classes, 

and both Guarea guidonia and 

Andira inermis are common species 

which produce cabinet quality timber. 

The most promising timber species are found in the small diameter 

classes in young secondary forests. 

These stands have the potential to 

develop into desirable sawtimber 

stands since the rough trees which 

dominate the coffee shade forests 

are absent. Less management effort 

would be required to concentrate 

the growth potential of the site in 

young, vigorous, desirable timber 

specles. 

Poor Tree Quality-Good timber stands are now found only in 

isolated, protected areas. The 

forests of 1980 more typically include a high percentage of rough 

and open-grown trees above a fairly 

dense, complex understory. 

The basal area of rough and rotten poletimber- and sawtimber-size 

trees is about 46 percent of the total. 

The larger diameter classes tend to 

have a higher percentage of rough 

and rotten trees than the smaller 

diameter classes (fig. 8). Coffee 

shade forests have the highest proportion, about half, of rough and 

rotten trees, although secondary 

trees predominate on shallow volcanic and granitic soils. 

Some pioneer species with good 

form, such as Cecropia peltata, 

Tabebuia heterophylla, and Didy - 

mopanax morototoni, are good timber species. Coffee shade species 

and fruit trees, all essentially opengrown, tend to include a high percentage of rough trees. Rotten trees 

amount to only about 3 percent of 

the basal area. 

Timber Volume 

Puerto Rico's timberland has 

been influenced by a series of land 

uses common in the tropics: removal of valuable timber species, clearing for agriculture, erosion and degradation, and finally abandonment. 

The forests now beginning to reclaim the land are extremely valuable as vegetative cover, yet they 

carry low timber volumes and a 

rather unfavorable mix of species 

and quality. The merchantable 

sawtimber volumes per hectare are 

generally low. 

Most Volume in Abandoned 

Coffee Country- The timber 

volume per hectare (stocked 

timberland) averaged 53.1 cubic 

meters in abandoned coffee plantations, 44.4 cubic meters in secondary forests, and 36.3 cubic meters 

in active coffee growing areas. Timber volume is highest on deep volcanic soils, averaging '73.3 cubic 

meters per hectare in the Subtropical Moist Forest Life Zone and 56.1 

cubic meters per hectare in the Subtropical Wet Forest Life Zone. The 

lowest volumes are found on granitic soils, which were recently abandoned, and limestone soils, which 

include much scrub vegetation. 

 more than 60 percent of the timber volume is found on slopes greater than 45 percent. Site quality is 

poor, and timber volumes average 

less than 50 cubic meters per hectare. 

The species accounting for most of 
pi 

........... SAWTIMBER 

POLETIMBER 

ROUGH 8 ROTTEN TREES 

SECONDARY 

FOREST 

THOUSAND CUBIC METERS 

Figure 9.-Timber volume by class of timber and forest class, Puerto Rico timberland, 1980. 

the wood volume reflect past land 

use. Ten species comprise about 60 

percent of the timber volume, eight 

of which were commonly used for 

coff'ee shade, fruit, or ornament. 

Some species such as Coffea arabica, Thouinia striata, Casearia 

guianensis, Cyathea arborea, and 

Myrcia splendens rarely attain 

large size, and this decreases their 

contribution to timber volume despite their abundance. Some species 

grow to larger sizes and have a high 

ratio of volume to basal area. Examples are the palms (Prestoea rnontuna and Roystonea borinquena), 

Hymenaea courbaril and Dacryodes 

excelsa. 

Low Sawtimber Volume-The 

volume of sawtimber (International 

Y4 inch rule) is less than one-tenth 

the timber volume. Only about one 

quarter of all sound wood (timber 

volume) is found in the sawlog portion of sawtimber-size trees, compared to about half for the Southern 

U.S. Poletimber trees and rough 

trees each account for about as 

much volume as sawtimber trees 

(fig. 9). Most existing stands are not 

ready for a sawtimber harvest, but 

timber growth might be stimulated 

by removal of rough trees and unwanted species. 

Stocked timberland averages 

about 4 cubic meters of sawtimber 

per hectare. Ten species represent 

65 percent of the sawtimber 

volume. These are the most common species, however a few such as 

Cordia alliodora and Dacryodes excelsa, are less common but grow to 

large size and have good form. 

Erythrina poeppigiana has the most 

sawtimber volume in the larger diameter classes, but it is not a good 

timber species. 

These low sawtimber volumes indicate that extensive harvests for 

sawtimber are unlikely in the near 

future. Immediate returns from the 

forest could come from mixed hard - .' 

wood pulp, fuelwood, or a combination of wood products. 

Commercial Prospects 

For Timberland 

Commercial prospects for harvesting timber are generally limited by economic factors, such as 

volume per hectare of merchantable species, size of forest tracts, 

operability, and distance to existing - 

all-weather roads. Other factors 

such as ownership patterns and 

attitudes, and distance to highways, lakes, and rivers are also important (FA0 1978, Deal 1980, Lee 

1980). 

Information about these items 

can be used to identify timberland 

which is currently suitable for commercial removals. Two critical 

assumptions must also be made, 

however, concerning factors outside 

the scope of this survey. First, that a 

market exists for all wood products 

of acceptable quality, and second, 

that private owners of timberland 

are willing to manage their land for 

timber production. These two relatively unknown factors have a 

great deal of influence on commercial prospects. 

The area of timberland with the 

greatest potential for timber production can be determined by sequentially eliminating areas which 

cannot satisfy a set of constraints, 

using a screening technique described by Knight (1980). The constraints would vary with the value 

and nature of merchantable wood 

products and with the size and nature of the harvesting operation. 

For example, a small operator removing selected trees for specialty 

wood products would not be concerned with small tract sizes or low 

timber volumes per hectare. The 

constraints used here (table VIII) 

screen out all but the best timber 

stands, leaving those which wouid 

interest a small or medium size 

commercial enterprise. Characteristics of these stands can then help 

determine commercial prospects. 

Elimination of areas unsuitable 

Tor harvest under these constraints 

xsrnoves 3/4 of the timberland. Low 

,awtirnber volume is clearly the 
most important factor, followed by 

poor ~perating cs.3 Jitions. The best 

timberland contain3 about 250,000 

cubic meters of &$;tfrnber, or an 

average of 8 cubic meters per hectare. This volume is relatively high 

for Puerto Rico. Much of the wood is 

in valuable hardwoods. About 1/2 of 

this forested area is abandoned coffee shade. I 

Physical conditions on harvestable timberland are much the same 

as for timberland in general. Most 

stands are close to an all-weather 

road. The terrain is rugged, generally uphill or up and down to the 

road. Many stands are littered with 

obstacles which would adversely 

affect felling and skidding. About 

half of the area is on slopes greater 

than 45 percent, difficult or impossible for most skidding equipment to negotiate, especially on wet 

clay soils. Skidding would also be 

heavily damaging to the site, an unacceptable practice for the wet, 

steep terrain. Practical alternatives to skidding include cable harvesting or low technology operations such as a winch and tractor, 

gravity, or animals lPestal 1976, 

FA0 1977, 1979). 

Although the current situation is 

generally unfavorable for extensive 

harvesting, some good stands are 

developing. Most of the forests are 

very young and timber volumes 

should increase significantly in the 

more vigorous stands. Better management could also bring about improvements in stocking and species 

composition. Commercial prospects 

in the future will depend on the development of effective management 

strategies. 

Management 

Opportunities 

Natural tropical forests, because 

of their complexity and diversity, 

are not as readily managed as 

forests in the temperate regions. 

There are only a few instances 

where a management system, 

based on sound silvicultural practices, has been successfully applied 

to mixed tropical forests. A more 

common practice has been to replace the natural vegetation with 

fast-growing native or exotic 

plantation species. In the absence of 

proven natural forest management 

techniques, plantations are more 

likely to succeed and produce a profitable crop. Puerto Rico's secondary 

forests fall somewhere in between; 

that is, they are not plantations, yet 

have been heavily influenced by 

man. 

In mountainous tropical regions 

conversion to plantation forests 

Table VII1.-Timberland with currently unfavorable commercial characteristics, Puerto Rico, 

1980 

Limiting factor Maximum area Area sequentially 

removed 

C ~rrent sawtimber volume less than 

1 5 cubic meters per hectare 

Poor operating condit~ons 

obstacles. precipices, 

Tract size less than 5 hectares 

Dtstance to all weather road more 

than 1 ktlometer 

Tract within 50 meters of highway, 

lake, or river 

Total area eliminated 

Prospective harvest area 31,100 

timberland - 130,500 - 

nT:s:, be done carefully. Some 

vcg";tztive cover must be maintained to minimize erosion and protect the water ~i~pply. Accelerated 

erosion can also reduce site productivity drastically, thus directly 

affecting wood yields. This constraint is particularly significant 

for a large area of forest land in the 

noncommercial survey region - 

which protects critical watersheds 

for the island, Management on 

these and other forest lands in the 

noncommercial category should 

continue to be custodial to preserve 

important resource values such as 

watershed, recreation, and wildlife 

habitat protection. 

Natural forest management 

schemes have had limited success in 

the tropics. Puerto Rico's secondary 

forests exhibit many characteristics which hinder forest management: 

-Difficult working conditions 

-Numerous species 

-Diverse ecosystems and site 

characteristics 

-High percentage of poor quality 

trees 

-Low stocking levels 

-Variable stand structure 

Management attempts have also 

been limited by funding, technician 

availability, and transportation 

facilities. Despite these difficulties, 

the presence of numerous young 

growing stock trees of good timber 

species makes management worthy 

of investigation. Recent advances 

in understanding the tropical forest 

ecosystem may provide a reasonably sound scientific basis for developing successful management 

practices in Puerto Rico and elsewhere. 

Some practices commonly applied in both t-emperate and tropical 

forests can be suggested as alternative management opportunities for 

various categories of timberland 

(table 1x1. These opportunities 

illustrate a range of possible 

courses of action. Only some of the 

techniques have been studied extensively in Puerto Rico. The de- 
Table IX -llfanagemenf opportunrtles for : arlous tzmberiand categories - - -- - - -- - -- - - - -- 

Timberland category Area 

i ha. 1 

Characteristics 

- - - -- - - -- - - - - 

Prospectl% e harvest area 

I less actit e coffee and ee table VIII I 

sapling seedlingi 

Nonstocked timberland 11 .TO0 Brush and inhlbitlng 

vegetation present 

All sapllng seedllng stands 29,100 Timber species present but 

1 except active coffee shade I not majority, some rough trees 

Active coffee shade 

Abandoned coffee shade: 

Sawt~mber stands 

t less exploitable timb. 1 

Abandoned coffee shade: 

Poletimber stands 

i less exploitable timb. 

Secondary forests: 

Sawtimber (less 

exploitable timberland) 

2 1,400 Low basal area, many rough 

trees, few small trees, 

species less complex 

Medium basal area, many rough 

trees, few small trees, species 

less complex 

Medium basal area, some timber 

species present. many rough 

trees 

Low basal area. some rough trees, 

complex species, number of growing 

stock trees acceptable 

Secondary forests: 14.100 High basal area, many growiag stock 

Poletimber t less trees, complex species lnclude 

exploitable timberland) timber species 

'Cleaning, release, or other intermediate cutting. 

'Remove or kill all trees and regenerate. 

velopment of management practices appropriate for Puerto Rico's 

young forests is the critical element 

which would allow the island's timber production potential to be realized. 

Timber stand improvement via 

the removal or killing of undesirable trees or inhibiting vegetation 

offers promising results on a significant area of poletimber and sawtirnber. As long as the current stand 

contains adequate stocking of 

acceptable trees, this is one of the 

- easiest and most reliable ways of 

improving commercial prospects. 

Harvestable timber already present could also be removed to help 

defray the treatment costs. 

Site preparation and artificial regeneration would be appropriate on 

all of the nonstocked timberland, 

and on a large proportion of the 

poorly stocked sapling-seedling 

stands. About 30,000 hectares could 

be treated this way. 

Many of the low volume sawtimber stands not included in harvestable timber are stocked with poor 

quality large trees which should be 

killed or removed. Enrichment 

planting or a full conversion to 

plantation would then be necessary. These treatments are expensive, however, and they offer little 

immediate return other than fuelwood or wood fiber. 

More than 20,000 hectares of coffee shade forests could supply timber as well as coffee and fruits, if 

timber production were incorporated into land management objectives. Some prior research would be 

needed, however, to determine 

which tree species could provide 

optimum shade. 

Harsest and regenerate 

Commercial thinning 

Timberland Stand Improvementi 

Arttficlai regeneration after site 

preparation 

Leave for natural regeneration 

Art~ficlal regeneration after srte 

preparation 

Pre-commercial thinn~ng 

Intensify agro-forestry efforts bj 

maximizing timber production and 

coffee production 

Stand conversion2 

Enrichment planting and cleaning 

Stand conversion 

Enrichment planting and clean~ng 

Timber Stand Improvement 

(best stands only J 

Enrichment planting and cleaning 

Timber Stand Improvement 

Timber Stand Improvement 

No treatment 

A sawtimber harvest followed by 

regeneration would be possible on 

about 30,000 hectares, and a larger 

area could be harvested for fuelwood or fiber. Much of the area 

would supply only a small return or 

no return on investment at all. A 

more appropriate treatment might 

be a commercial thinning or a stand 

improvement cut. 

Tables VIII and IX constitute 

classifications which attempt to 

provide direction in a complex 

situation. A management program 

would have to consider also the 

different soils, Life Zones, and regions. This analysis is intended to 

establish very broad guildelines for 

the kind of research on management of secondary forests, and agroforestry, which is urgently needed 

in Puerto Rico, and elsewhere in the 

tropics. 

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Tree ferns rn the Caribbean Natronal Forest 
Appendix 
SURVEY METHODS 

The 1980 survey u7as primarily descriptive and exploratory. The main purpose was to assess the secondary forests of Puerto Rico. The data are used to describe both the timber resource in Puerto Rico and the 

ecological characteristics of secondary tropical forests. 

The survey also establishes the basis for a continuous 

assessment of Puerto Rico's forest resources. Subsequent surveys will build upon the existing data base. 

In order to focus the survey on areas with commercial potential, land uses which exclude intensive timber production were identified and delineated on a 

1:120,000 scale base map and excluded from the 

ground sample. The potential commercial region was 

stratified by ecological Life Zone and soil type. 

The data on forest acreage, timber volume, and species composition were obtained by a sampling method 

involving a forest-nonforest classification on aerial 

photographs and on-the-ground measurements of 

trees at sample locations. The sample locations were at 

the intersections of a grid of lines spaced 3 kilometers 

apart. Within the area of commercial potential, 10,925 

photographic classifications were made and 437 

ground locations were visited. The estimates of forest 

area obtained from the aerial photographs were adjusted on the basis of the ground check. 

The estimates of forest acreage and timber volume 

for areas excluded from the ground sample were developed using several data sources. Partial aerial 

photographic coverage enabled an additional 3,875 

forest-nonforest classifications to be made. Adjustments to these estimates of forest area were made by 

extrapolating ground truth information from similar 

regions visited in the ground sample. Regions without 

adequate photographic coverage were assessed using 

reference material. 

A cluster of 3 variable-radius plots was established 

at each ground sample location. Each sample tree on 

the variable-radius plot represented 2.5 square meters 

of basal area per hectare, or 0.83 square meters of 

basal area per hectare when the plots were clustered. 

Trees less than 12.5 centimeters in diameter at breast 

height were tallied on fixed-radius plots of approximately 40 square meters around the plot centers. 

Each sample location was classified by numerous 

site characteristics. Each sample tree 12.5 centimeters 

9nd larger was measured and assessed to determine 

wood volume and quality. Species was accurately determined for more than 99 percent of all sample trees. 

Ground sample locations were selected on U.S. 

Geological Survey topographic maps and transferred 

to aerial photographs. The center of each forest location was established on the ground by running a computed azimuth and distance from a selected starting 

int. Each plot at a sample location was marked so 

that future surveys can reestablish the plot and estimate growth, mortality, removals, and changes in 

land use. 

Specific measurements and estimates made at each 

sample location generally follow the procedures used 

to assess timber in the Southern U. S. (CSDA Forest 

Service, 1977). Modifications were made, however. to 

account for basic differences in the nature of secondary 

tropical forests as compared to southern forests. All 

procedures followed in Puerto Rico were assembled - 

into a handbook of field instructions. Important modifications included the use of the metric system for 

measurements, separate assessments of sound and unsound cull volume, and a tally of all sound wood in bole 

and branches to a minimum 10 centimeter diameter. 

RELIABILITY OF THE 

DATA 

Reliability of the estimates may be affected by two 

types of errors. The first stems from the use of a sample 

to estimate the whole and from variability of the items 

being sampled. This is termed sampling error; it is 

susceptible to a mathematical evaluation of the probability of error. The second type -often referred to as 

reporting or estimating error -derives from mistakes 

in measurement, judgment, or recording, and from 

limitations of method or equipment. The Forest Service attempts to hold it to a minimum by proper training, supervision, and precision. 

The Puerto Rico survey required a special team 

approach to satisfy fieldwork requirements for accuracy. In addition to the regular problems associated with 

measuring and estimating tree characteristics, the 

heterogeneous species composition required special 

knowledge of Puerto Rican dendrology. The approach 

teamed experienced timber cruisers from the Southern 

area with dendrologists and botanists from Puerto 

Rico. 

A one-week training session was held in Puerto Rico 

to familiarize the timber cruisers with the characteristics of tropical trees, to standardize measurements and 

estimates, and to develop working teams. A noted taxonomist was hired as a consultant to identify unrecognized tree species. 

Statistical analysis of the data indicates a sampling 

error of plus or minus 1.5 percent for the estimate of 

total timberland, and 7.6 percent for timber volume. 

As these totals are broken down by various strata, 

species, tree size, and other subdivisions, the possi bility of error increases and is greatest for the smallest 

subdivisions. The order of this increase is suggested in 

the following tabulation, which shows the sampling 

error to which the timber volume and area estimates 

are liable, two chances out of three: 
Sampling errors for tirnberlzd and timber volumes, 

Puerto Rico, 1980 

Timberland Sampling Tinber Sampling 

errori vo'iume error1 

thousand 

hectares percent cubic meters percent 

130,500 1.5 5433.8 7.6 

5 1,200 3.5 2519.7 14.0 

20,800 4.4 348.6 19.6 

8,900 9.9 . . . . . . 

'By random-sampling formula 

The sampling error for estimates based on extrapoIated or secondary information cannot be determined. 

These estimates should be considered less reliable 

than the estimates for timberland and timber volume. 

DEFINITIONS OF 

TERMS 

Forest Land Class 

Forest Land-Land at least 10 percent stocked6 by 

forest trees of any size, or formerly having had such 

tree cover and not currently developed for nonforest 

use. The minimum area for classification of forest land 

is ?Lz hectare, and the minimum width for forest strips 

is 35 meters. Unimproved roads and trails, streams, 

and clearings in forest areas are classed as forest if less 

than 35 meters in width. 

Timberland-Forest land that is producing or is 

capable of producing crops of industrial wood and not 

withdrawn from timber utilization. Forest lands with 

higher priority uses, yet not specifically withdrawn 

from timber utilization, are excluded from this class of 

forest land. These excluded lands were delineated on a 

base map. CofTee shade is included in this category. 

Noncommercial forest land-Forest land incapable of yielding crops of industrial wood because of 

adverse site conditions, forest land withdrawn from 

timber utilization through statute or administrative 

regulation, or forest land with higher priority use (except coffee shade). 

'Ten percent of "normal" stocking as defined for the Midsouth forest 

survey. 

Nonstocked land-Commercial fr !and less 

than 10 percent stocked6 with grow-. -, .:k trees. 

This includes areas covered by inhibitl-rls -e.;letation 

I brush, vines, ferns, etc.) classed as forest lar,d. 

Secondary forest land-Forest land resulting 

from the abandonment of cropland or pasture, and 

forest resulting from the regeneration of previously 

cutover or disturbed forest land. Abandoned coffee 

shade is excluded from this class. 

Coffee shade-A multi-story, multi-crop system 

used principally for the production of coffee. An upper 

story of shade trees is characteristic. 

Abandoned coffee shade-Secondary forest land 

resulting from the abandonment of coffee production 

under shade trees. 

Timberland Strata 

Subtropical Moist Forest-Forest occurring in an 

ecological Life Zone delineated by a mean annual rainfall of 1000 or 1100 millimeters to about 2000 or 2200 

millimeters, and a mean biotemperature between 

about 18 and 24 degrees centigrade (Holdridge 1967). 

Subtropical Wet Forest-Forest occurring in an 

ecological Life Zone delineated by a mean annual rainfall of about 2000 to 4000 millimeters, and a mean 

annual biotemperature between about 18 and 24 degrees centigrade (Holdridge 1967). 

Deep volcanic soils-Deep soils of the wet volcanic 

uplands, with clayey texture, typically red and acid 

(Zambrana 1978). The soil depth is generally more 

than 50 centimeters. 

Shallow volcanic soils-Shallow soils of the wet 

volcanic uplands, with clayey texture (Zambrana 

1978). The soil depth is generally less than 50 centimeters. 

Granitic soils-Shallow soils of the wet uplands 

with granitic origin, and with a typically sand clay 

loam texture (Zambrana 1978). 

Limestone soils-Shallow soils over limestone, 

found in the moist coastal hills (Zambrana 19781. 

Noncommercial Forest Strata 

Subtropical Dry Forest-An ecological Life Zone 

delineated by a mean annual rainfall of between 600 

millimeters and 1000 or 1100 millimeters, and a mean 

annual biotemperature between about 18 and 24 degrees centigrade (Holdridge 1967). 

Critical watersheds-Upland areas with an average slope greater than 60 percent or rainfall greater 

than 2500 millimeters per year. These areas require a 

continuous protective forest cover. Some timber removal would be feasible; however, much of the area is 

not highly productive. 
Unproductive soils-Soils incapable of .;leiding timber-size trees, and with poletimber basal area excrops of industrial wood. ceeding that of sawtimber basal area. 

Alluvial regions-River floodplains ~~th agrlcul- Sapling-seedling stands-Stands with at least 5 

tural land use. quare meters per hectare of basal area, with more 

31etropolitan regions-Regions with primarily than half of this basal area in saplings or seedllngs, or 

urban or residential use. stands with less than 5 square meters per hectare of 

Mangrove and swamp-Coastal wetlands with basal area. 

unique characteristics and values requiring special 

management considerations. 

Noncontiguous regions-Islands and other land 

bodies separated from mainland Puerto Rico. 

Class of Timber 

Growing stock trees-Sawtimber trees, poletimber trees, saplings, and seedlings: that is, all live trees 

except rough and rotten trees. 

Desirable trees-Growing-stock trees that have no 

serious defects to limit present or prospective use, are 

of relatively high vigor, and contain no pathogens that 

may result in death or serious deterioration before 

ratation age. These trees would be favored in silvicultural operations. 

Acceptable trees-Trees meeting the specifications for growing stock but not qualifying as desirable 

trees. 

Rough and rotten trees-Live trees that are unmerchantable for sawlogs now or prospectively because of defect or rot. 

Sawtimber trees-Growing stock trees, 22.5 centimeters and larger in dbh for softwoods and 27.5 centimeters and larger for hardwoods, and containing at 

least one 3.5 meter sawlog. 

Poletimber trees-Growing stock trees 12.5 to 22.5 

centimeters in dbh for softwoods and 12.5 to 2'7.5 centimeters for hardwoods, and of good form and vigor. 

Saplings-Growing stock trees 2.5 to 12.5 centimeters in dbh, and of good form and vigor. 

Salvable dead trees-Standing or down dead trees 

that are currently or potentially merchantable. 

Stand-Size Class 

Sawtimber stands-Stands with at least 5 square 

meters per hectare of basal area in sawtimber or pole- 

* timber-size trees, and with sawtimber basal area at 

least equal to poletimber basal area. 

Poletimber stands-Stands with at least 5 square 

meters per hectare of basal area in sawtimber or poleVolume 

Volume of sawtimber-Net volume of the sawlog 

portion of sawtimber trees in cubic meters, calculated 

according to the International rule, 0.635 centimeter 

inch) kerf. 

Volume of growing stock-Volume of sound wood 

(less cull volume) in the bole and branches of sawtimber and poletimber trees from stump to a minimum 10 

centimeter diameter outside bark or to the point past 

which a one-meter section meeting minimum qualifications can no longer be measured because of limbs 

or other cull. 

Volume of timber-Volume of all sound wood (including sound cull) in the bole and branches of growing 

stock, rough. rotten. and salvable dead trees 12.5 centimeters and larger in dbh, from stump to a minimum 10 

centimeter diameter outside bark. The minimum 

length of any section included is one meter. 

Miscellaneous Definitions 

Basal area-The area in square meters of the cross 

section at breast height of a single tree or of all the 

trees in a stand, expressed as square meters per 

hectare. 

Dbh (diameter at breast height)-Tree diameter 

in centimeters, outside bark, measured at 1.3 meters 

above ground. 

Log grades-A classification of logs based on external characteristics as indicators of quality or value. 

Logs are graded according to standards used for hardwoods in the southern U.S. Grade 1 logs have very 

little sweep, crook, cull, or other defects, are the 

largest, and are suitable for standard lumber. Grade 4 

logs need only be 20 centimeters at the small end, and 

are used only for ties and timbers. Grades 2 and 3 are 

between the two extremes. 
STANDAR.7: TABLES 

Forest Area 

Page 

1 .-Area by t and classes ........................................................................... 40 

2.-Forest area by Life Zone and forest class ........................................................ 40 

3.- Area of timberland by Life Zone, soil group. and forest class ...................................... 40 

4.- Area of timberland by stand-volume class and forest class ........................................ 41 

5.- Area of timberland by stand-volume class and soil group ......................................... 41 

6.- Area of timberland by stand-size class and forest class ........................................... 41 

7.- Area of timberland by stand-size class and soil group ............................................ 42 

8.-Area of timberland by stand age class and forest class ........................................... 42 

9.-Area of timberland by stand age class and soil group ............ , ............................... 42 

10.-Area of timberland by basal area class and forest class ................. , ......................... 43 

11 .- Area of timberland by basal area class and stand-size class ....................................... 43 

12.- Area of timberland by Life Zone, soil group, and slope class ...................................... 43 

Species Composition 

13.....Number of live trees by species and diameter class, ranked by basal area plurality ................ 44 

14.-Number of growing stock trees by species and diameter class, ranked by basal area plurality ....... 46 

15.- Number of live trees on stocked timberland by diameter class and forest class ..................... 48 

16a.- Basal area and number of live trees per hectare of stocked timberland for selected species, 

secondary forests .............................................................................. 48 

16b.-Basal area and number of live trees per hectare of stocked timberland for selected species, abandoned 

coffee shade ................................................................................... 49 

16c.- Basal area and number of live trees per hectare of stocked timberland for selected species, active 

coffee shade ................................................................................... 49 

17.- Basal area of poletimber and sawtimber trees by tree class and forest class ........................ 50 

18.-Basal area of poletimber and sawtimber trees by tree class, Life Zone, and soil group .............. 50 

Timber Volume 

19.-Volume of timber on timberland by class of timber and forest class ............................... 51 

20.- Volume of timber on timberland by Life Zone, soil group, and tree class ........................... 51 

21.- Volume of timber on timberland by species and diameter class ................................... 52 

22.- Volume of growing stock on timberland by species and diameter class ............................. 54 

C . 23.- Volume of sawtimber on timberland by species and diameter class ................................ 33 

24.- Volume of sawtimber on timberland by species and butt log grade ................................ 56 

25.- Volume of timber, growing stock, and sawtimber on timberland by stand-size class ................ 56 

26.- Volume of timber on timberland by Life Zone, soil group, and slope class .......................... 56 
Table 1 -Area bt land classes, Puerlo Rlco, 1980 - - - - - - - - - - - 

Land class 

Forest 

Commerc~al survey region 1 timberland) 

Publ~c 

Prlvate 

Total 

Noncommercial survey region 

Subtropical Dry Forest Zone 

Critical watersheds 

Other' 

Total 

Total Forest 

Nonforest 

Commercial survey region 

Cropland 

Pasture 

Other2 

Total 

Noncommercial survey region 

Table 2.--Foreai urea by L~fi Zone and forest land class, Puerto Rrco. 

l9h: - - 

Subtropical All Timberland Noncommerctai hectares Llfe Zone' forest land forest land 

8.200 .................... hectares ------------------- 

122,300 Dry Forest 40,500 . .. 40,500 

hlolst Forest 122,400 60,400 62.000 

130.500 Wet Forest 103,700 70.100 33.600 

Rain Forest 

Lower Montane 

Wet Forest 

Lower Montane 

Rain Forest 

Total 

'According to Holdridge system t Holdridge 1967 1 

Total Nonforest 

All land 

11 C nproductive soils, alluvial and metropolitan regions, mangroves 

and swamps, non-contiguous land areas. 

'Idle farmland, water, roads and rlghts of way, urban and industrial 

areas. 

Table 3.-Area of tzmberland by Lzfe Zone, sozl group, and forest class, Puerto R~co, 1980 - - - - - 

Forest class - -- - - -- -- - 

All Secondary Abandoned Active Nonstocked 

Life Zone and soil group classes forest coffee shade coffee shade areas 

Subtropical Moist Forest 

Deep volcanic soils 

Shallow volcanic soils 

Granitic soils 

Limestone soils 

Total 

Subtropical Wet Forest 

Deep volcanic soils 

Shallow volcanic soils 

Granitic soils 

Limestone soils 

Total 
Table ' .,-pa of timberland by stand-bolume class and Forest class, Pr~ertc R (rc. 1980 - - 

Timot-: , ne 

 cub:^ rrii"icr.5 

per hectare I 

---------------- ---------------- hectares ---- --.-----.--...-------------- 

Less than 25 52.700 27,200 17.200 8,600 11,700 

25 to 50 59,200 14,700 15,800 8,700 

50 to 75 16,400 3,700 9,500 3,200 

75 to 100 12.000 5,500 .5.600 900 . . 

llore than 100 10,200 8,100 - - - - - - - - 2.100 - . . ---- - - 

All classes 130,500 59.200 38.200 21,400 1 f ,700 

Table 5.-Area of t~rnberland by stand-tolume class and sod group, Puerto Rtco, 1980 - -- - - - 

Timber volume - -- - - - - -- - Soii group 

1 cubic meters All Deep Shallow Granitic L~mestone 

per hectare) groups volcanic volcanic 

..................................... hectares .................................... 

Less than 25 52,700 14,600 15,900 7,800 14,400 

25 to 50 39,200 19,900 7,400 7,600 4,300 

50 to 75 16,400 8,100 3,400 2,000 2,880 

75 to 100 12,000 9,000 1,900 1,100 ..... 

More than 100 10,200 - - 8,300 -- ---- ---- 1,900 . . . . . ..... -- 

All classes 130,500 59,900 30,500 18,500 21,600 

Table 6.-Area of t~rnberland by stand-s~ze class and forest class, Puerto Rico, 1980 -- -- - - - - 

Forest class - - - -- - - - - - - - -- - -- 

A11 Secondary Abandoned Active Nonstocked 

Stand-size class classes forest coffee shade coffee shade areas - - - -- ---- - -- --- -- -- -- 

..................................... hectares ..................................... 

Sawtimber 40,900 15,300 17,800 7,800 . . 

Poletimber 44,700 18,700 16,500 9,500 

Sapling and seedling 33,200 25,200 3,900 4,100 .... 

Nonstocked areas - 11,700 ... . .. .. .. 1 1,700 -- - -- - -- - -- - - - - - 

All classes 130,500 59.200 35.200 2 1,400 11,700 - - -- - - - --- - - -- - - - -- - - 
Table 7 -Area of t~mberland by statzd-stze class and sot1 group, Puerto Rtco, 2980 - --- - -- - -- - -- - - - -- -- 

S0ll group - - - -- - - - 

All Deep Sha1lo.r~ Gran~tlc Llme~tone 

Stand-slze class groups volcan~c voicanic 

................................... hectares .................................. 

Sawtrmber 40,900 2 1.800 9,700 5,000 4.409 

Potet~mber 44.700 27,900 5,600 8,300 2,900 

Sapling and seedling 33.200 8.200 10,800 4.100 10.100 

Xonstoeked areas 11,700 2.000 4,400 - --- - -- --- -- -- - - - 1,100 - 

4.200 

All classes 130.500 59,900 30,500 18.500 21,600 

Table 8.-Area of tzmberland by stand age class and forest class, Puerto RLCO, 1980 --- - -- - - - - -- 

Forest class -- - 

Stand age All Secondary Abandoned Active Nonstocked 

(years classes forest coffee shade coffee shade areas -- - -- - - - -- -- -- - 

..................................... hectares ..................................... 

Less than 30 86,300 42,200 16,900 15,500 11,700 

More than 30 38,000 14,900 18,100 5,000 . . . . . 

Mixed ages 6,200 2,100 3,200 900 ..... -- - - - --- - 

All ages 130,500 59,200 38,200 2 1,400 -- ---- -- - - 

11,700 

Table 9.-Area of timberland by stand age class and sod group, Puerto Rrco, 1980 - - - - - --- - -- - 

Soil group 

Stand age All Deep Shallow Granitlc Limestone 

(years) €CrOUPS volcanic volcanic 

..................................... hectares .................................... 

Less than 30 86,300 38,300 22,600 15,300 10,100 

More than 30 38,000 18,900 7,900 2,600 8,600 

Mixed ages 6,200 2,700 ..... 600 2.900 - -- --- - - -- - - -- - .- - 

All ages 130,500 59,900 30.500 18,500 2 1,600 
Table 10.-Area of tzmberland by basal area class and forest class, Puerto Rrco, 1980 

Basal area Forest class - -- - --

square meters A11 Secondary Abandoned Active Nonstocked 

per hectare) classes forest coffee shade coffee shade areas 

------------------- ------------------ hectares ...................................... 

Less than 5 21,100 8.000 1,400 11,700 

5 to 10 34,900 13,200 9 300 12,400 

10 to 15 52,600 15,800 10,500 6 300 

15 to 20 24,700 3,100 13,900 2,700 

20 to 25 8,700 6,500 2,200 

25 to 30 8,500 7,600 - - - - - 900 

All classes 130,500 59,200 38,200 21,400 11,700 

Table 11.-Area of timberland by basal area class and stand-size class, Puerto Rico, 1980 

Basal area -- Stand-size class 

c square meters All classes Sawtlmber Poletimber Sapling & N~r~stocked 

per hectare) seedling areas 

...................................... hectares - - - - - - - -- - - -- - - - - - - - - - - - - - - - - - - - - - - - - - 

Less than 5 21,100 ..... ..... 9,400 11,700 

5 to 10 34,900 15,500 5,400 14,000 ..... 

10 to 15 32,600 7,000 18,600 7,000 ..... 

15 to 20 24,700 12,700 10,600 1,400 ..... 

20 to 25 8,700 2,900 4,400 1,400 ..... 

25 to 30 -- 8,500 2,800 5,700 ..... -- ..... 

All classes 130,500 40,900 44,700 33,200 11,700 

Table 12.-Area of stocked timberland by LLife Zone, soil group, and slope class, Puerto Rico, 1980 

Life Zone and 

soil group 

Percent slope class -- 

All classes 0 to 10 11 to 25 26 to 45 More than45 

................................ hectares - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 

Subtropical Moist Forest 

Deep volcanic soils 7,700 1,900 ..... 1,900 3,900 

ShalIow volcanlc sods 16,900 2,900 2,200 5,200 6,600 

Granitic soils 9.600 .... 3,700 1,500 4,400 

Limestone soils' 17.400 3,500 ..... ..... 11,600 

Total 5 1,600 10,600 5,900 8,600 26,500 

Subtropical Wet Forest 

Deep volcanic soils 50,200 1.800 5,400 12,500 30,500 

Shallow volcanic soils 9,200 ..... ..... 2,300 6,900 

Gran~tic soils 7,800 ..... ..... 1,100 6,700 * 

Total 67,200 1,800 5,400 15,900 44,100 

All areas 118,800 11,400 11,300 24,500 70,600 

'Includes small area from Subtropical Wet Forest. 
- c =x33~q==wbC~?3 6ze==*W====- 

LC , 3d"- -- 3 

Lri 

C* 

5 

t+tO~~OWW~hCOW 63303P,%OZCC5 Lcrn=Oor-(Dm9 ~2-m~ rr ma 04 m ma* ?? 

C, 


.tirt rt,i,/~~,/~, ( h1-1 zopli, /lo~tft,s l'let 1 I* 

illI(}t~)~t'/i,'~cl/[~b (~~1/1#2/1.21.5 (Ldlll A f(.l~jl ex Wdl 

(1' utrci Irur o;lyfutt (Sw ) M~L 

Spottdlas rtto~rt b111 1. 

'ibrt~z lrtalla culuppa L 

Uyrsontmu cortucea (Sw. ) I.)( 

Ntvtattdra s~rltertlslr hle~ 

Zunthoxylurrt tt~urtitzu~er~.~t. ( L,dm ) UC. 

Artocurpus ultrlts t hrklnson) Fosbetg 

Muttgrferu lntlrcu L. 

Buchenauru cuprtutu iVahl) Eichl 

Neetandru trzerrtbrc~riacea (Sw.) Griseb. 

Phoebe elorzgatu (Vahl) Nees 

Quthea arborea (L.) J.E Smith 

Clus~u roseu Jaccl. 

Loncfiocurpus pentuphyllu:, (Poir. ) L)C. 

Buc~da buceras L. 

Syrrtplocos nzarttrz~censrs Jacq. 

Orr~~os~a krugrr Urban 

Meltosnzu herbertil Rolfe 

Dtphol~s sulic~fol~u (L.) A.D.C. 

Petztru dornz~tgenszs Jacq. 

Necturtdru cortaceu (Sw.1 Cr~setu. 

Mrcropholts garciriraefol~a Pierre 

Other specles (35) 

All species 

'l'otals may not add due to rounding. 
T&:e 1.5 -1Vumber of Zzue trees on stocked tzmberland by d~arneter class and forest class. Puerto Rrto 

1980 

Forest class 

Dtarneter - -- - -- -- - -- -- -- - - -- ---- - - 

class All Secondary Abandoned Actice 

(centimeters f classes forest coffee shade coffee shade 

- - 

5 

10 

15 

20 

2 5 

3 0 

3 5 

40 

45 

50 

55 + 

All classes 

----- trees per hectare ------- 

2,220 1,307 

3 10 191 

107 96 

5 5 49 

2 6 3 5 

16 24 

8 11 

5 7 

2 4 

1 2 '11 4 

2,752 1,728 

'Less than one tree per hectare. 

Table i6a.-Basal area and number of lrve trees per hectare of stocked ttmberland for selected speczes, secondary forests, Puerto RLCO, 19801 -- -- - - -- -- -- - - - - - 

Species 

code 

Scientific 

name 

Basal area - - - --- - . - -- - - 

Square meters Number of trees 

per hectare Percent per hectare 

Cecropza peltata L. 

Tabebuza heterophylla (DC.) Britton 

Guarea gutdonta (L.1 Sleumer 

Eugenul jambos L. 

Inga uera Willd. 

Andzra tnermts (W. Wright) DC 

Spathodea campanulata Beauv. 

Prestoea montana iR. Grah.) N~chols. 

Calophyllum calaba L. 

Mangtfera zndtca L. 

Roystonea bortnguena O.F. Cook 

Thoutnta strrata Radlk. 

Ocotea leucoxylon (Sw. I Mez 

Alchornea Latzfolta Sw 

Dtdymopanax morototonz iAubl J Decne & Planch 

Myrc~a splendens i Sw i DC 

Clus~a rosea Jacq. 

Terebrarza reslnosa (Vahl i Sprague 

Casearra gutanensts r Aubl. i Lrban 

lnga faglfolta iL 1 Willd. 

Tetrazyg~a eiaeagnotdes (Sw i DC 

Dzpholzs saltctfolta iL.1 A.D C 

Unidentified specles 

Guettarda scabra (L. 1 Vent. 

Psrdtum guajaca L 

Other specles ( 147 1 

All specles -- - - - - - 

'Totals may not add due to rounding. 

"otential timber species. 
Table 16b.-Basal area and numheroflli Q treesper hec: iked ttmberland for selected spectes, abandoned coffee shade, Puerto Rrco, 1980" - -- - -- -- - - - - --- - - - -- --- - - - - - - -- - --- - - 

Basal area 

Species 

code 

Sclentlfic 

name 

Guarea gutdonia L i Sleurner 

Inga .ern Wtlld 

Inga iSzgzblza f L., WI Ild 

Cecrop~a peEtota L 

Andlra incrrnts 1 W Wr~ght) DC. 

Erythrlna poepplgzana (Walp.) O F Cook 

Dendropanax arboreus f L. 1 Decne & Planch 

Cztrus sLnensLs Osbeck 

12fang~fera rnd~ca L. 

Spathodea campanulata Beauv 

Eugenza jumbos L. 

Drdyrnopanax morototont iAub1.i Decne. & Planch. 

Coffea arabtca L. 

Ocotea leucoxylon (Sw. Mez. 

iVectandra stntentsts Mez. 

Cordta sulcata DC. 

Cttharexylum fruttcosum L. 

Zanthoxylum marttn~cense t Lam.) DC. 

;Mtconta praszna i Sw.) DC. 

Cordta alltodora (Ruiz & Pav.) Oken 

Other species (61) 

All species 

Square meters 

per hectare Percent 

Number of trees 

per hectare 

'Totals may not add due to rounding. 

'Potential timber species. 

Table 16c.-Basal area and number of live trees per hectare of stocked timberland for selected species, actiue coffee shade, Puerto Rico, 1980' 

Basal area 

Species 

code 

Scientific 

name Square meters Number of trees 

per hectare Percent per hectare 

Inga vera Willd. 

Guarea gutdonta tL.1 Sleumer 

Andtra tnermcs (W. Wright) DC. 

Coffea arabtca L. 

Inga fagzfolza tL.1 Willd. 

C~trusznenscs Osbeck 

Cecrop~a peltata L. 

Dendropanax arbo~eus (L. 1 Decne. 6i: Planch. 

Anthocephalus chznensts (Lam.) A. Rich. ex Walp. 

Cyathea arborea iL.) J E. Smith 

'Vectandra rnernbranacea (Sw 1 Griseb. 

Cordta allzodora (Ruiz & Pav.1 Oken 

Ficus cltrtfolza Mill. 

Tabebu~a heterophylla (DC.1 Br~tton 

Coffea dewevrec Wildem. & T Dur. 

Cltdemla umbrosa r Sw f Cogn. 

H~btscus elatus Sw. 

Erythrzna poepptgtana {Walp.) O.F. Cook 

LMang~fera lndtca L. 

Cordla sulcata DC. 

Other specles (24) 

All specles 

"lbtals may not add due to rounding. 

'Potential timber species. 

,'Less than 1. 
Table 17.-Basal area of poletzmbtr and sau ttm her trees by tree class and forest class, Puerto R~co, 

1980 -- -- -- -- - -- - - - - - - - --- -- - 

Forest class - - - -- - - - -- - - - - - - - 

A11 Secondary Abandoned Active 

Tree class classes forest cofTee shade coffee shade -- -- - -- -- - - -- - - 

------------------- square meters of basal area ------------------- 

Polet~mber-size trees: 

Growlng stock 333,900 183,700 98,400 5 2,800 

Rough & rotten - 227,000 96,300 -- -- -- - - 

87 .OOO 43,700 - - - - -- - 

Total 560,900 280.000 185,400 - -- - - -- - - - -- - 

95,500 - - - ---- - - - - - - 

Sawtimber-sue trees: 

Growing stock 25 1.400 111,300 107.000 33,200 

Rough & rotten 265,400 103,100 120,300 41,900 - - - - - - - -- - - - ----- - 

Total 516,800 214,400 227,300 75 100 - - --- - - - -- -- - - - - - - -- - 

All growing stock 585,300 295,000 205,400 85,000 

All rough & rotten 492,400 199,400 207,300 85,600 - - -- 

All poletimber & sawtimber 1,077,700 494,400 412,700 170,600 - 

Table 18.-Basal area ofpoletmber and saqlmber trees by tree class, Llfe Zone, and soil group, Puerto R~co, 1980 -- -\- ---_I----- _ - _- -- --- - - - - - -- - 

Soil group Tree class - - 

and All Deep volcanic Shallow volcanic Granit~c Limestone 

Life Zone €TOUPS solls soils soils soils - -- - 

Subtropical Moist Forest 

Poletimber-size trees 

Growing stock 

Rough & rotten 

Total 

Sawtimber-size trees 

Growing stock 

Rough & rotten 

Total 

All growing stock 

All rough & rotten 

Total 

Subtropical Wet Forest 

Poletimber-size trees 

Growing stock 

Rough & rotten 

Total 

Sawtimber-size trees 

Growing stock 

Rough & rotten 

Total 

All growing stock 

All rough & rotten 

Total 

All Life Zones 

.............................. square meters of basal area .............................. 




Table 23.-Volume of sawttrnber on i~mberland by speczes and drarrr ' -s, Puerto Rrco, 1980' -- -- -- - - - - ---- - -- -- 

I>l-jrrt :. - - 1 centimeters~ - --- 

Specles All 3 0 ,3 5 40 43 50 55 and 

code Sc~entrfic name classes greater 

Inga Lera Wllld 

Guarea guidonla r L 1 Sleumer 

Crcropra peltata L 

Andtra tnerrnts W Wright) DC 

Inga fbgifol~a L Wtlld. 

Eugen~a jumbos 

Spathodea campanulata Beauv 

.tlang~fera indrca L. 

Erythrzna poepptglana (Walp 1 

0 F. Cook 

Dendropanax arboreus i L ) Decne. 

Sc Planch. 

Dtdymopanax morototont t Aubl. J 

Decne. & Planch. 

Calophyllum calaba L. 

Alchornea lattfolta Sw 

Cordta sulcata DC. 

Clldemza umbrosa (Sw.) Cogn. 

Unidentified species 

Cordta all~odora t Ruiz & Pav.) 

Oken 

Lonchocarpus pentaphyllus (Pox 

DC 

Nectandra stntentszr Mez. 

Cedrela odorata L. 

Spondras mombtn L. 

Mtcropholts chrysophyllotdes 

Pierre 

Zanthoxylum martzntcense (Lam.) 

DC. 

Byrsoncma corzacea iSw. DC. 

Artocarpus alttlts (Parkinson) 

Fosberg 

il.ltcon~a praslna (Sw ) D.C. 

Pouterta mult~flora (A.DC) Eyma) 

,Montezuma speccossLma Sesse 

& Moc. 

Magnolta portorzcensts Bello 

Hymenaea courbar~l L. 

Dacryodes excelsea Vahl 

Spondtas dulcts Parkinson 

~Wel~osma herbertzt Rolfe 

Sloanea bertertana Choisy 

itlammea amerzcana L. 

Buchenauza capttata (Vahl) Eichl. 

Terrntnalta catappa L. 

Sy mplocos martt ntcensts Jacq. 

liltex dtvarzcata Sw. 

Roll~nta mucosa tJacq.1 Baill. 

Nectandra membranacea (Sw.) 

Gnseb. 

Phoebe elongata iVahi Nees 

Polygala penaea L. 

Other species 

Totals 

--------------- thousand cubzc meters ------- 

22.1 12.3 12.3 6.1 

8.8 14.2 6.8 5.9 

26.9 22.1 11.9 4 8 

2.6 5.0 4.8 0.0 

19.3 6 2 5.4 4.6 

0 5 0.0 1.0 0.0 

7 1 4.2 3.3 0.0 

0.0 0.0 1.3 2.1 

'Totals may not add due to rounding. 
Table 24 -Volume of sawttmber on timberland by speczes and butt log grade. Puerto R~co. I980 -- - -- - -- - - - -- - - -- - - --- - --- - 

Species 

code Scientific name 

All - - 

classes 1 

Butt log grade' -- - Volume In 

2 3 4 ungraded portlon 

Irzga Lera Wlild 

Guarea guzdon~a {L, i Sleumer 

Cecropla peltata L 

Andrra rnermts IW. Wr~ghtl DC 

Znga fq;;Tblta iL.) Wllld. 

Spathodea campanulata Beauv 

Erythrina poeppLgtana tWalp ) O F Cook 

Dtdymopancu: morototon~ (Aubl. i 

Decne. & Planch. 

Calophyllum calaba L. 

,%ftconta sp. 

Cordra all~odora (Ru~z & Pav ; Oken 

Spond~as mornbzn L. 

Dacryodes excelsea Vahl 

,Vectandra membranacea (Sw 1 Griseb. 

Other species 

All Species 

thousand cubic meters - 

1.9 6.6 36.9 

1.8 11.6 23.9 

9.0 6.7 44.1 

1.6 3.4 4.1 

0.0 3.6 23.8 

0.8 0.8 14.2 

7.9 3.3 6.4 

'Graded by hardwood log grade standards used in the southern C.S 

Table 25.-Volume of ttrnber, grouctng stock, and sawt~rnber on 

ttmberland by stand -sLze class, Puerto R LCO, 1980 

Volume of Volume of Volume of 

Stand-size class timber growing stock sawtimber 

-------------- thousand cub~c meters -------------- 

Sawtimber 2,565 5 1,435.1 286.1 

Poletimber 2,519.7 1,584.7 179.1 

Sapling-seedl~ng 348.6 180.3 18.7 

All classes 5,433.8 3,200.1 484.7 

Table 26.-Volume of tzmber on tzmberland by Life Zone, sot1 group, and slope class, Puerto Rico. 1980 -- - - - - --. 

Life Zone and -- Percent slope class - - -- -- - - - -- -- - 

soil group All classes 0 to 10 11 to 25 -- - - --- - -- - - - - - - --- 

.................................. thousand cubic meters .................................. 

Subtropical Moist Forest 

Deep volcanic soils 

Shallow volcanic soils 

Granitic soils 

Limestone soils 

Total 

Subtropical Wet Forest 

Deep volcanic soils 

Shallow volcanic soils 

Granitic soils 

Total 

All Life Zones 5,433.8 543 0 490.2 1.074 7 3,325.9 
UNIT CONVERSION FACTORS 

Metric to English and English to Metric Conversions 

1 cm. = 0.393'7 in. 1 in. = 2.54 em. 

1 m. = 3.251 ft. 1 ft. = ,3048 in. 

1 km. = .6214 mi. 1 mi. = 1.6093 km. 

1 sq. m. = 10.7639 sq. ft. 1 sq. ft. = 0.0929 sq. m. 

1 sq. km. = 0.3861 sq. mi. 1 sq. mi. = 2.59 sq. km. 

1 ha. = 2.471 ac. 1 ac. = 0.4047 ha. 

1 cu. m. =35.3145 cu. ft. 1 cu. ft. = 0.0283 cu. m. 

1 sq. m. per ha. = 4.356 sq. ft./ac. 1 sq. ft.,ac. = 0.2296 sq. m.. ha. 

1 cu. m. per ha. = 14.29 cu. ft.,ac. 1 cu. ft.,'ac. =0.07 cu. m.:ha. 

METRIC INVENTORY 

STANDARDS USED IN 

THE 1980 SURVEY 

Item Pdetric standard 

Prism size BAF 2.5 

Grid spacing 3 km. 

Cluster point spacing 25 m. 

Fixed plot size 40 m.?r = 3.6 m.) 

15 m.2(r = 2.2 m.) 

Breast height 1.3 m. 

Stump height 30 cm. 

Diameter classes 5cm. = 2.5 to 7.5 cm. dbh 

10cm. = 7.5 to 12.5cm. dbh 

15cm. = 12.5 to 17.5cm. dbh 

20cm. = 17.5 to 22.5cm. dbh etc, 

Tree size classes 

Sapling 2.5 to 12.5 cm. dbh 

Poletimber !hardwood) 12.5 to 27.5 cm. dbh 

Sawtimber (hardwood) 27.5 cm. + dbh 

Sawtimber (softwood) 22.5 cm. 4 dbh 

Minimum top D.O.B. 

Cubic volume 10 cm. 

Hardwood sawlog 22.5 cm. 

Softwood sawlog 17.5 cm. 

Sapling 2.5 cm. 

Minimum D.I.B. sawlog 

Hardwood 20 cm. 

Softwood 15 cm. 

3linimum length 

Cubic section 1 m. 

Sawlog 2.5 rn. 

Sawtimber tree 3.5 m. sawlog 
LIST OF TREE SPECIES INCLUDED IN STANDARD 

TABLES 

Code 

number Scientific name Common name 

Cyathea arborea (L. J.E. Smith 

Prestoea montana (R. Grah.) Nichols. 

Roystonea borinquena O.F. Cook 

Artocarpus altilis (Parkinson I Fosberg 

Cecropia peltata L. 

Ficus Citrifolia Mill. 

ivagnolia portoricensis Bello 

Xectandra coriacea (Sw.) Griseb. 

Ocotea leucoxylon (Sw.) Mez 

Inga fagifolia (L.) Willd. 

Inga Vera Willd. 

Hymenaea courbaril L. 

Andira inermis (W: Wright) DC. 

Erythrina poeppigiana (Walp.) O.F. Cook 

Lonchocarpus pentaphyllus (Pair.) DC. 

Ormosia krugii Urban 

Citrus sinensis Osbeck 

ZanthoxyLurn rnartinicense (Lam.) DC, 

Dacryodes excelsea Vahl 

Cedrela odorata L. 

Guarea guidonia (L.) Sleumer 

Byrsonima coriacea (Sw.) DC. 

Alchornea latifolia Sw. 

Mangifera indica L. 

Spondias dulcis Parkinson 

Spondias rnombin L. 

Thouinia striata Radlk 

kleliosrna herbertii Rolfe 

Sloanea berteriana Choisy 

Montezuma speciossirna Sesse & Moc. 

CalophyLlurn calaba L. 

Clusia rosea Jacq. 

Mammea americana L. 

Casearia guianensis (Aubl.) Urban 

Casearia syluestris Sw. 

B uchenauia capitata (Vahl) Eichl. 

Bucida buceras L. 

Terminalia catappa L. 

Eugenia jambos L. 

iwyrcia splendens iSw.1 DC 

Psidium guajaua L. 

Miconia prasina (Sw.) DC 

Tetrazygia elaeagnoides (Sw.) DC 

Dendropanar arboreus (L.) Decne. & Planch. 

Didymopanm morototoni (Aubl.) Decne. & Planch. 

Dipholis salicifolia (L.) A.D.C. 

Micropholis chrysophyllo~des Pierre 

It;l~rropholis garciniaefolia Pierre 

p-,,.:: . :a multiflora (A.DC.) Eyma 

Helecho gigante, tree-fern .r 

Palma de sierra, sierra palm 

Palma real, royal palm, Puerto Rico royalpalm 

Panapen, pana de pepitas, breadfruit 

Yagrumo hembra, trumpet-tree 

Jaguey blanco, shortleaf fig 

Jaguilla 

Laurel avispillo, Jamaica nectandra 

Laurel geo 

Guama, "sweetpea" 

Guaba 

Algarrobo, West-Indian-locust 

Moca, cabbage angelin 

Bucayo gigante, mountain immortelle 

Retama 

Palo de matos 

China, sweet orange 

Espino rubial, white-prickle 

Tabonuco 

Cedro hembra, Spanish-cedar 

Cuaraguao, American muskwood 

Maricao 

Achiotillo 

Mango 

Jobo de la India, ambarella 

Jobo, hogplum, yellow mombin 

Ceboruquillo 

Aguacatillo 

Motillo 

Maga 

Maria, santa-maria 

Cupey, wild-mammee, copey clusia 

Mamey, mammee-apple 

Palo blanco, wild-coffee 

Cafeillo 

Granadillo 

Ucar, gregre, oxhorn bucida 

Almendra, Indian-almond 

Pomarrosa, Rose-apple 

Hoja menuda 

Guayaba, common guava 

Camasey 

Verdiseco 

Poll0 

Yagrumo macho, matchwood 

Sanguinaria, wild mespel, willow bustic 

Caimitillo 

Caimitillo verde 

Jacana 
LP;.'?:? OF TREE SPECIES INCLUDED J -. STANDARD 

TABLES-Continued 

Code 

number Scientific name Common name 

SympLocos martzn~censis Jacq. 

Cordia alliodora i Ruiz & Pav.) Oken 

Cordia sulcata DC. 

Citharexylum fruticosum L. 

Petitia domingensis Jacq. 

Vitex divaricata Sw. 

Spathodea campanulata Beauv. 

Tabebuia heterophylla (DC.) Britton 

Coffea arabica L. 

Guettarda scabra (L.) Vent 

Terebraria resinosa (Vahl) Sprague 

Rollinia mucosa (Jacq.) Baill. 

Nectandra mern branacea (Sw.) Griseb. 

~Vectandra sintenisii Mez. 

Phoebe elongata (Vahl) Nees 

Polygala penaea L. 

Hibiscus elatus Sw. 

Clidemia umbrosa (Sw.) Cogn. 

Anthocephalus chinensis t Lam.) A. Rich. 

Coffea dewevrei Wildem. & T Dur. 

Aceituna blanca, candlewood t 

Capa prieto, capa 

Moral, white manjack 

Pendula, pasture fiddlewood, Florida fiddlewood 

Capa blanco 

Higuerillo, white fiddlewood 

Tulipan africano, African tuliptree 

Roble blanco, "white-cedar" 

Cafe, coffee 

Palo de cucuban6; "greenheart," roughleaf velvetseed 

Aquilon 

Anon cimarron 

Laurel prieto 

Laurel amarillo 

Laurel avispillo 

.... *....a 

bfajo, mahoe 

Camasey 

ex 'CValp. Kadam 

Cafe excelsa, dewevre coffee