/

as FORESTATIO.

^RO

of STRIP- MIN i

in the Central States

United States Department of Agriculture

Forest Service • Agriculture Handbook No. 166
FORESTATION

of STRIP- MINED LAND

in the Central States

By G. A. Limstrom, forester

Central States Forest Experiment Station

Forest Service

Agriculture Handbook No. 166 Februarv 1960

UNITED STATES DEPARTMENT OF AGRICULTURE

Washington, D.C.

For sale by the Superintendent of Documents, U.S. Government Printing Office

Washington 25, D.C. - Price 35 cents
ACKNOWLEDGMENT

The information contained in this publication was obtained from

research started in 1937 and from a project begun in 194-5 to intensify the study of strip-mine reclamation problems in the Central

States. Organized and directed by A. G. Chapman, the project personnel included a number of other staff members wliose contributions

are gratefully acknowledged.

Cooperation, lai'gely in the form of laboratory analyses, from the

following State institutions is also appreciated: The Ohio Agricultural Experiment Station, the Purdue University Agricultural

Experiment Station, Illinois Agricultural Experiment Station, Kentucky Agricultural Experiment Station, Iowa State College Agricultural Experiment Station, Missouri Agricultural Experiment Station, Kansas State College of Agriculture and Applied Science,

and Oklahoma Agricultural and Mechanical College.

Assistance in conducting much of this research was provided by

the coal mining industry, chiefly : L. E. Sawyer of the Indiana Coal

Association, Larry Cook of tlie Ohio Reclamation Association, John

Reiser of the Ohio Power Companv, Tom Clieasley of the Sinclair

Coal Company, John Crowl of tlie Kentucky Reclamation Association, Inc., and A. J. Christiansen, L. S. Weber, and James W. Bristow of the Illinois Coal Stripping Association.

Ill
FOREWORD

Land recently strip mined for coal is not a pretty sight, nor is it

producing anything. This apparent desolation need not be permanent, however, because it is possible to reclaim most of this land—

improve its appearance and restore it to productivity.

One of the best ways to do this is to establish forest cover. However, because the artificially produced site conditions on mine spoil

banks are so unlike most natural planting sites, commonly accepted

principles and practices of artificial forestation are not always successful. In fact, it was because the coal mining companies ran into

so many new problems in getting plantations started on their stripmined land that public forest research agencies were called upon

to tackle the problem.

Personnel at the Central States Forest Experiment Station have

been engaged in this field of research since in;57. All this work was

done in nine midwestern States—Arkansas, Illinois, Indiana, Iowa,

Kansas, Kentucky, Missouri, Ohio, and Oklahoma. Although many

of the principles and procedures developed appl}" to forestation work

on any land stripped for coal, differences in topography, climate,

and vegetation in neighboring States may limit the application of

some of the results reported in this publication.

As research results became available, they were immediately made

known in publications (£ß) and progress reports, and by field demonstrations. There is perhaps no better example of quick acceptance

of forestry research than the speed with which these results were

adopted by the mining companies in reclaiming their land. The

early application of research results in this field reflects the need and

public demand for information of this kind.

This publication summarizes the knowledge gained during the past

two decades and is intended to serve as a guide for technicians engagerl in forestation of strip-mined land. It attempts to answer the

question: "Where, when, and how sliould tree planting be done on

such land? (^hief emphasis is placed on a detailed discussion of

site conditions that affect forestation on strip-mined land. After

that, the planting operation itself is described.

IV
CONTENTS

Page

Site conditions affecting forestation of strip-mined land 3

Physical characteristics 3

Amount of stone and soil 3

Texture 4

Aggregation " " 5

Classification f;

Chemical condit ions ß

Survival and growth g

Field tests and classification... 12

Nutrient availability 12

Topography I3

Vegetation 15

Origin of bank "site" 17

Parent material 18

Limestone 19

Sandstone . 21

Shale 22

Clay 22

Loess 22

Glacial material 23

Alluvium 24

Soil 24

Methods of mining 24

Grading 26

Types of grading 26

Grading and soil moisture and aeration 27

Grading and microclimate 31

Grading and survival and growth of plantations 32

Erosion . 34

Erosion and productivity 34

Erosion and forestation practice 34

The net effect 36

Establishing the forest 37

Natural forestation 39

Direct seeding 41

Tree planting 42

Choosing the species 42

Climate 43

Lisects and diseases 43

Seed sources, hybrids, and varieties 46

Planting stock qualitv 47

Care of stock ." 49

Planting seasons 50

Planting methods 51

Spacing 51

Pure or mixed planting 5z

Black locust as a "inirse" tree 53

Planting recommendations 5.)

Growth and yield ö3

Summary ö6

Literature cited 6'

Appendix ¡P

Common and scientific names of trees mentioned '0

Planting site evaluation record J.^

Sulfide tests i^

Materials needed i,^

Procedure '^

Acidity tests !^2

Materials and methods i^

Samphng procedure

COVER PHOTO F-485130

V
Forestation of Strip-Mined Land

in the Central States

By G. A. Limstrom

Strip mining for coal has become big business in the United

States. When this country entered the Second World War, coal

mined by stripping amounted to about 11 percent of the total production (-5-Í).' During the following 7 years this percentage more

than doubled. In the Central States region alone, the total area of

land strip mined for coal was nearly :^(H),()()() acres through 1947,

the last year for which reliable estimates for the region as a whole

are available (Hg. 1) (¿-9). There is no evidence that stripping has

declined during the last decade. In some States the total area strip

mined has more than doubled since 1947. Overall, the area atfected

is insignificant. In some localities, however, where the amount of

stripped land may exceed 5 percent of the total area in a county,

the restoration of stripped land to some productive use has, in turn,

become biff business.

' Italic numbers in parentheses refer to Literature Cited, page 67.

FIGURE 1.—Location and concentration of strip mining

for coal in the Central States.

Each dot represents not

more than 1,000 acres of

strip-mined land.
2 AGRICULTURE HANDBOOK NO. 166, U.S. DEPT. OF AGRICULTURE

By 1947 more thi\n ;>;5,()()() acres of stripped land supported wellestal)lished forest plantations. Since llnit time the tempo of reclamation Inis kept pace with the increase in strip mininjr. In some

States a liigh percenta<re of plantin«; stock produced in public

nurseries is allocated for the forestation of strip-mined land (If.3).

Tree planting; is not the only way to reclaim strip-mined land;

in some States much of the total strip-mined area is used for pasture. But tree planting does combine several benefits that some of

the other methods do not produce. P'irst, of course, trees will eventually produce a salable croj), whether it be in the form of Christmas trees, posts, pulpwood, or sawtimber. Not much is known about

the yields of the larjrer timber products, but, as will l)e shown later,

evidence so far indicates that trees planted on strip-mined land often

grow as fast as those planted on other land, and sometimes faster.

Then there is the well-recognized capacity of some tree species to

stabilize slopes. On some strip-mined land no other vegetational

cover is as effective a watershed management tool as trees. And

finally, forested strip-mined land nuikes good parks and wildlife

habitat, which in turn help to fill the ever-increasing demand for outdoor recreational facilities. The innumerable ponds and small lakes

formed by simple impoundment procedures in many parts of the

region have proved to be excellent water for game fish (fig. 2) {I^J^).

Along these watercourses many good camping and picnic grounds

have been established.

F-485117

FIGURE 2.—Tree planting can help convert strip mines to attractive recreation

areas such as this one.
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES ó

SITE CONDITIONS AFFECTING FORESTATION OF

STRIP-MINED LAND

Site conditions on strip-mined land are unique; they are so different from those on otlier land surfaces that a sejjarate classification

of factors influencino; tree growth is needed. The bi<r ditference

between site conditions for «rrowino- trees on strip-mined land and

on undisturbed land lies in the differences of the rootinc: mediiim.

On lands undisturbed by strip minin<>:, the soil is an organized natural body resultiufi' from the modification of parent materials near

the earth's surface; the rootin<r medium on strip-mined land is an

unorganized mass of liiaterial derived from any or all strata between

the earth's surface and the coal seam mined. Strip-mined surfaces

differ also from land surfaces made Ijarren by erosion and toxic

gases; in the latter situations the underlying strata have not been

moved while in the strip-mining operation they have been overturned and mixed. Depending on the number and kinds of strata

overturned, bank surfaces are sometimes rather uniform in character, but great variation even within small areas is more common.

To account for the behavior of tree growth on strip-mined land, an

understanding of the important site factors is essential.

PHYSICAL CHARACTERISTICS

The conditions that influence aeration and moisture of bank materials are the most important physical characteristics affecting plantation establishment and growth. These include the amount of

stone present, and the texture and aggregation of the soil. (In this

text, "soil" includes only mineral particles less than 2 millimeters in

diameter; particles smaller than 2 millimeters are sands, silts, or

clays; particles larger than this are called "stones.")

Amount of Stone and Soil

The relative amoimts of stone and soil on the surface of stripmined land have a bearing on readiness for planting, method of

planting, and planting success. Drainage would be so rapid and

M-ater retention so low on banks composed entirely of loose stones

that few planted trees would survive. Because of natural weathering processes and the common occurrence of some soil in the overburden, this condition seldom exists.

The minimum percentage of soil needed for planting vanes from

one kind of bank to another. Only a small amount of soil, however,

is needed. Good initial survi\al on banks with only 20 percent soil

has been reported by Bramble (6') and Clark (/J). At least part

of this success is attributed to moisture lodged in or adhering to

stones—a factor which until recently has been ignored m soil moisture studies. In a recent study of the moisture content of small

stone in several Piedmont soil^profiles, Coile (14) found that the

water supply in stones a\ailable to plants ^•aried with the size, concentration, and composition of stones present, and that stones contributed to the water supply available to plants.

513.374 O—60 2
4 AGRICULTURE HANDBOOK NO. 166, U.S. DEPT. OF AGRICULTURE

Thill water held by stones may account for frood survival on some

banks with a hif^h percentan;e of stone is borne out in observations

by Stiver US). He observed free water between the laminae of

siiale particles even durinji the dry month of Auojust. "On the

dull Idack shales, which are very loose in structure, free water has

been found in a dry Auo;ust at à 3-inch deptli. The water remains

in the shale because there is not a continuous water column in any

direction, the large pores in such a loose structure having no attraction for the water.''

The relative amounts of stone on bank surfaces have an important bearing on the methods of planting that can be used. Often

this factor alone will determine whether an area can be planted by

mattock, bar, or machine methods.

Texture

Texture—usually recorded as the relative amounts of sand, silt,

and clay in a soil—influences moisture and aeration conditions on

strip-mined land to about the same degree as in undisturbed soils.

The amount of stone on bank surfaces changes rapidly from year to

year because of weathering and erosion. As a result, the relative

amount of soil—and to some extent its texture—changes during the

rotation period of a timber crop. So in planning the reclamation of

stripped land by forest planting, only three broad textural classes

need be recognized :

1. Sand.—Soil containing less than 20 percent silt and clay. The

stones usually associated with this class are sandstones and sandy

shales.

2. Loan).—Soil containing less than 80 percent sand and less than

30 percent clay. Most of the stones associated with this class are

siltstones and silty shales.

3. f'Jay.—Soil containing more than 30 percent clay. Most of the

stones associated with this class are limestones, clay shales, and marl.

These classes can be easily recognized in the field. Field classification can be verified by mechanical analysis (^. 57). Because the

proportion of stone has an imj^ortant effect on drainage and aeration,

the soil textural class may be modified by adding "Stony", "Shaly",

or "Gravelly" wherever appropriate.

The various responses of trees on banks of different soil texture

are evident at an early age. Second-year survival and mean total

heights of trees planted on three strip-mined areas of different soil

textures show that, in general, early survival and growth are better

on the finer textured soils than on the sands (table 1). Excessive

drainage, resulting in droughty conditions, perhaps accounts for

most of the generally poorer survival and growth on the sandy area.

The clay soil, on the other hand, would be poorly drained but for

the fact that it contains 25 to 3.^) percent stones. This tends to

make drainage and moisture conditions nuich more favorable for

tree growth than in soils of this heavy texture without stones on

midisturbed land. For some species, liowever, such as the pines,

green ash, ])lack locust, cottonwood, and silver maple, early development on sandy areas appears satisfactory.
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES

TABLE 1.—Second-year surriral and total height oj trees planted on

strip-mined banks oj three different soil textures

Species

Eastern redcedar

Jack pine..

Red pine

Eastern white pine

Pitch pine

Green ash

Black locust

Black walnut seed

Eastern cottonwood- -

Silver maple

Black walnut

Soil texture

Sand

Survivnl

Percent

22

59

61

55

47

01

85

21

71

80

1

Height

Feel

0. 9

. 7

. 4

. 5

. 4

0

6

9

0

4

7

Stony loam

Survival

Percent

74

84

70

59

97

94

98

79

64

79

36

Height

Feet

0. 6

. 8

. 5

. 5

. 6

. 9

4. 5

. 7

2. 2

1. 5

Stony clay

Survival

Percent

59

94

94

81

84

97

95

53

70

93

21

Height

Feet

0.

2.

2.

' Tops of all trees partly dead.

Aggregation

In strip mining, the material overlying the coal is broken up into

fragments of various sizes and shapes. Piled on the banks more or

less at random, these fragments may, during the weathering process,

distintegrate into small aggregates or form larger ones. The degree of aggregation and the stability of the aggregates have an

important eti'ect on the water movement, erodibility, and productivity of strip-mined land. The kind and amount of aggregation in

strip-mine bank surfaces depend a great deal upon the structure and

consistence of the original strata occurring in the overburden before

stripping.

As pointed out by Baver (3), there have been a number of definitions and classifications of soil structure, all based on difl'erent

points of view and intended methods of application. Kegarded

usually as denoting the arrangement of soil particles, the structure

of soil is often described by such terms as "granular," "cubelike,"

"fragmentai," "platy," "blocky," and "single-grained."

Soil consistence includes such properties as resistance to compression and shear, friability, plasticity, and stickiness (J). Whereas

structure refers to the degree of aggregation of soil particles, consistence denotes the force by which soil particles are held together.

Soil consistence is often described by such terms as "loose," "compact," "friable," "crumbly," "plastic," "sticky," and "cemented." For

field classification of consistence, the procedure outlined in the Soil

Survey Manual (^6) appears practicable. It is based on the resistance

to change in shape under varying degrees of applied stress when

moistened enough to be at or slightly above field capacity. ^Yhen it

can be rolled to form a rod or wire of soil and much pressure is

required before deformation takes place, the soil is said to be very

plastic; if no rod is formable, it is nonplastic.
6 AGRICULTURE HANDBOOK NO. 166, U.S. DEPT. OF AGRICULTURE

]\Iiiieralo<iiciil unalyse.s may also be ]ie]])fiil. Soils made up mainly

from quartz and feldspar are apt to be nonplastic, Avliereas those

roui])osed mainly of kaolinite, talc, muscovite, or biotite will most

likely be plastie {.>). The montmorillonite clays are also highly

plastic.

Only a few plasticity tests of bank materials have been made up

to the present time. Those that have been made disclose such close

coi-relation with textuie that a separate consideration of this factor

in site evaluations for tree ])lantin<r on strip-mined land does not

appear necessary. Tlie si<;niHcance of structure and consistence in

the productivity of strip-mined land has, moreover, not been completely evaluated. For the present, then, the importance of these

two soil properties is recognized only by their relation to the aggregation of bank materials.

Only two types of aggregation, rather easily identified, are considered pertinent in classifying strip-mined land for tree planting:

1. Loofie bank materials.—"When holes are dug with a spade or

mattock, the exca^'ated material falls into a loose, unconsolidated

pile, either as individual (single-grained) mineral particles or as

aggregates usually smaller than 1 inch in diameter (fig. 3). Tf

large stones are present, little or no soil adheres to them. Holes are

easily dug with a spade. Footprints are clearly defined. Valleys

become U-shaped in a year or so (fig. 4, .1).

2. Compart hank material'^.—Excavated material falls into clods

or aggregates larger than 1 inch in diameter. If large stones are

present, soil particles adhere to them. Much pressure is needed to

insert the spade into the ground ; in fact, a pick or mattock is

almost always needed for digging holes. Footprints are scarcely

visible except when wet. Valleys remain V-shaped for many years

(fig. 4,^).

The effects of loose and comj^act bank surfaces on tree survival

and growth are difficult to separate from the eifects of other site

factors; the combined effects of many of these factors are discussed

in the section on "The Net Effect," page 36.

Classification

Strip-mined banks are classified into bank types as follows: (1)

sands, (2) loams, and (3) clays {25). In each bank type, classes

may be differentiated by the degree of aggregation, that is, loose

or compact. In many cases it is useful to recognize différent phases

of stoniness. These various criteria, already discussed, for classifying the physical characteristics of strip-mined banks are combined

to form descriptive terms considered useful in appraising such land

for tree planting. Some of the most common of these terms are

sands, stony sands, loose shaly loams, compact loams, compact stony

clays, loose shaly clays, and compact clays.

CHEMICAL CONDITIONS

The acidity or alkalinity of bank materials is an important site

condition to consider in reclaiming strip-mined land. It is, in fact,

very often the limiting factor for plant growth. In making site
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES

i.iT'W

r-485116, 485115

FicuRE 3.—Different kinds of aggregation; A, Loose, shaly clay, easily dug with

ordinary garden trowel;" B, " compact, ' stony clay, difficult to dig even with

hoes and mattocks. Note large clods in B.
8 AGRICULTURE HANDBOOK NO. 166, U.S. DEPT. OF AGRICULTURE

r-485114, 485123

FinuRE 4.—^1, Loose, shaly, clay banks have developed U-shaped bottoms in

less than 2 years; B, compact, stony clay banks retain their V-shape for many

years.
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES

appraisals on strip-mined lands in the region, the most practical

method for determining the range of acidity or alkalinity is by taking a number of pH determinations (33). A pH of 4.0 or less is

considered very strongly acid and generally indicates conditions

lethal to most plants. A pH of 4.0 to 5.0 is strongly acid; 5.1 to

6.9 is moderately to mildly acid; 7.0 is neutral. A pH liigher than

7.0 is alkaline (usually calcareous in the Central States).

Survival and Growth

Data are lacking on maximum and minimum pH values for the

survival and growth of a large number of tree species {4-7) However, Stiver (48) observed that Virginia pine on strip-mined land

in Indiana survived in media having a pH of 3.5. On three different strip-mined areas in Ohio, the total height of 2-year-old black

locust was almost twice as great on surfaces where pH ranged from

6.8 to 7.8 as on surfaces where the range was from 3.0 to 5.5 (32).

Stunted growth of Avhite pine, white ash, and yellow-poplar has

been observed in the transition zone between toxic areas having pH

values below 4.0 and areas of good growth having pH 4.5 and higher

(fig. 5; table 2).

Soil acidity in itself does not, within limits, influence plant growth.

Rather, it influences the availability of soil nutrients, chiefly in

affecting the solubility of minerals (ßi) for absorption by plant

roots, and in affecting the occurrence and abundance of soil microt^.f-fFiouRE 5.—Ten-year-old white pine plantation on strip-mined land in Ohio.

Barren area in right foreground (pH less than 3.8) was planted at the same time

as the remainder of the plot. Note stunted growth of pine in transition zone

between the highly acid area and the plantable area in background where pU

is generally more than 4.5.
10 AGRICULTURE HANDBOOK NO. 166, U.S. DEPT. OF AGRICULTURE

TABLK 2.—Eßect oj pH on hnght of 10-year-old planted trees on graded

banks in Ohio

Specit'.s pH 3.0-4.1 pH 4.2-4.6 pH 4.7-5.2

Yellow-poplar

White ash

Ea.stern wliite pine.

Feet

5. 3

7.2

Feet

14.0

2. 6

Feet

11. 5

6.7

or<ï!\nisins. For more .specific iiiforiiiation, liowever, it is necessary

to turn lo studies on afiricultural plants. In controlled laboratory

experiments, Arnon and Jolmson (2) tested the development of

tomatoes, lettuce, and Bermuda prass plants in media ran<;ing in

pll from 3.0 to !).() with all nutrients except sulfates at a constant

concentration. Tliey drew two principal conclusions from these

experiments: "P"irst, that fatal or profoundly adverse effects of

extei'nal reaction are encountered only at extremes of acidity and

alkalinity (pll 3.0 and 9.0) ; and second, that with certain reservations, fluctuations in hydroojen ion concentration pe?' se. within the

relatively wide ranoe of pil between 4.0 and 8.0, are not inimical

to the welfare of the plants so far studied." At pH 8.0 the plants

were unable to absorb calcium and phosphate, and at pH 9.0 phosphate absorption was drastically curtailed. In the pH range from

4.0 to 8.0 good growth was possible only when special safeguards

were taken to assure a good supply of nutrients.

Many kinds of bacteria, particvdarly those known to be nitrogenfixing, thrive in soil with pH values greater than 5..5. Some nitrification, liowever, takes place below a pH of 5.5. Certain species of

fungi, for example, "are able to effect those enzymic transfers" in

media with lower pH values (3ß). Sulfur-oxicíizing bacteria can

survive in media of extremely high acidity.

Even though acidity has an important effect on the relative

amounts of available elements, specific information on the optimum

range for each species is lacking. Much research in this field of

study is needed (55).

The pH determination is, however, a good indicator of several

forms of toxicity. In strongly acid soils, capable of dissolving

compounds of sulfur, iron, aluminum, and manganese, a plant may

absorb so much of these substances that it may be injured or die.

On strip-mined land most of the mortality attributed to toxicity is

associated with high concentrations of sulfuric acid in the bank

matei-ials. The most common source of the sulfuric acid on stripped

land is iron sulfide, which occurs chiefly as pyrite in the coal and

in certain rocks making up the overburden most commonly in the

roof coal, carbonaceous shales, and sandstone. As stripping proceeds,

some of these sulfides are expo.sed to air and water and, upon oxidation in the presence of oxygen and water, .sulfuric acid is formed.

Äficro-organisms, found even in banks devoid of vegetation {56),

no doubt influence the extent and duration of toxic materials on

strip-mined land. Oxidation processes are most likely accelerated

by sulfur-oxidizing bacteria. Reduction of the acid to hydrogen
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 11

sulfide by sulfur-reducing bacteria, on the other hand, may also

occur.

The strongly acid surfaces on stripped areas appear as dark, moist,

and somewhat greasy-appearing spots and are most easily observed

during warm, dry weather (fig. 6). The relatively high moisture

content of these spots is due mostly to hygroscopic action of the

acid. The extent and duration of strongly acid conditions on bank

surfaces depend on the amount of sulfur-bearing rocks i:)resent as

well as many interacting forces. AYeatliering, leaching, and runoff

gradually reduce the concentration of acid on bank siirfaces. However, on some erosive areas, the continual exposing of unoxidized

material tends to prolong conditions of high acidity.

All the factors that tend to reduce acidity of bank surfaces are

not yet known; such factors as climate, topography, the form of

compoimds in which the Sulfides occur and their concentration, and

the activity of soil micro-organisms are no doul)t important. From

four tests of highly acid bank surfaces in "West Virginia, Tyner and

Smith {51) reported that reductions of total sulfur content varied

from about 25 to 50 percent in 1 year. If the same rates of reduction continue, they estimated that in 3 to 5 years these surfaces

would support vegetation similar to adjacent bank surfaces with

pH values varying from 4.6 to 5.6. These authors have, on the

other hand, reported highly acid conditions on other bank surfaces

more than 20 years old, with only a remote probability of vegetation

developing unless limed {5£).

FIGURE 6.—A toxic, strip-mined area. The highly acid areas are darl<, moist,

and ''greasy" in appearance.

613374 O—60-
12 AGRICULTURE HANDBOOK NO. 166, U.S. DEPT. OF AGRICULTURE

Field Tests and Classification

Acidity conditions may vary greatly on some stripped areas; tlie

pll may, in fact, vary from 3.0 to 7.5 in spots only a foot apart.

In forestation practice, however, only the predominant pH range

for a given area should be considered. This can be determined by

making a nmnber of acidity tests, the number to be made depending

on the size of the area, the uniformity of acidity conditions, and

the degree of accuracy desired. Five classes of acidity are generally

recognized {S5) :

1. Toxic.—More than 75 percent of the area with pH values less

than 4.0.

2. Marginal.—50-75 percent of the area with pH values less than

4.0.

3. Acid.—More than 50 percent of the area with pH values from

4.0 to 6.9.

4. Calcareous.—More than 50 percent of the area with pH values

of 7.0 or above.

5. Mixed.—Acidity values so varied that the area cannot be classified as toxic, marginal, acid, or calcareous.

Toxic areas are considered nonplantable; planting on marginal

sites is considered desirable mainly for soil and landscape improvement. Banks classified as acid, calcareous, or mixed are plantable.

Marked increases in acidity liave been ol)served on some mine

banks over a number of years after stripping {18). This has been

attril^uted to the presence of many hard, slowly weathering rocks

containing a higli percentage of Sulfides. If acidity tests within a

year after stripping disclo.se doubt of the plantability of the area,

tests for Sulfides should also be made {4'2) (see p. 72). As a general

rule, however, acidity conditions improve on bank surfaces with the

passing of time. Some stripped areas in Ohio, for example, have

changed from "toxic'' to "acid" in the relatively short span of 8 years.

NUTRIENT AVAILABILITY

Although the nutrient requirements for many agricultural crops

are well known, the relation of soil nutrients to site quality in forestry is still rather obscure. Evidence to date indicates that nutrient requirements for tree growth are generally much lower than for

cultivated crops and that tlie requirements for conifers are usually

less than for hardwoods {35). Nevertheless, nutrient deficiencies for

some species do occur often enougli to warrant attention to them.

Nutrition studies liave pointed out the various requirements of a

few species for each element. Heiberg (Sí2) has shown the disastrous effects of potash deficiencies on the growth of certain conifers;

Mitchell and Chandler (4/) and Finn {'20) have correlated growtla

of a number of hardwoods witli varying amounts of foliar nitrogen,

phospliorus, potassium, calcium, and other elements.

Recent analyses of samples taken from strip-mined land in the

Central States reveal tliat amounts of potentially available phosphorus and potash may differ {21. SO. 1^5, 1^8). But in general the

amounts available have been greater than those found on adjacent

unmined land. Boron, for example, one of the so-called minor ele-
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 13

ments but necessary to plant growth, ^Yas found in "medium" and

"high" amounts on stripped land in Illinois {Jt9).

Although nitrogen is generally lacking in freshly mined material,

in a few years the quantity available increases enough to meet the

requirements of many trees. This increase comes mainly from rainfall and from leguminous plants {12). On ?>- to 5-year-old banks

planted to black locust, for example, foliar analyses conducted by

Finn ('20) disclosed available nitrogen as well as phosphorus, potassium, and calcium in amounts comparable to those generally found

on other land.

On a number of acid strip-mined areas low in phosphorus. Stiver

{.1^8) tested the effects of adding various amounts of lime and rock

phosphate on spots planted to Virginia pine. No discernible effects

on survival or growth were observed. In other plots on the same

banks, where ai^ abnormal yellow cast on 2-year-old Virginia pine

was observed, nitrogen fertilizer was used. The applications (80

pounds of ammonium nitrate per acre) Avere made on May 1 and

by June 1 the yellow cast hacl disappeared. Moreover, growth in

diameter of tlie new shoots Avas 2 to 3 times greater on the treated

plots than on the untreated.

Site quality for a number of tree species has been found to be

correlated with certain physical characteristics of the soil. The

preceding section showed that nutrient availability is affected by

acidity. It is apparent, tlien, that the main effects of soil nutrients

in promoting tree survival and growth are associated with physical

characteristics of the soil and its acidity. For these reasons, the

evaluation of initrient availability per se in the general classification

of strip-mined land for forest planting is not yet considered advisable or necessary at tliis time. As research progresses, however,

there is little doubt that nutrient deficiencies will be found to be a

limiting& factor on some sites.

TOPOGRAPHY

Topography influences survival and growth largely through its

effects on soil moisture, soil depth, light, temperature, erosion, and

protection from wind. Some of these effects in turn are affected by

physical characteristics of the bank materials.

Soil moisture studies on stripped land in Ohio and Kansas {28)

disclosed that, except for periods of prolonged drought, there is

only a little difference in moisture conditions between slopes of

different exposures. Although during dry periods in late summer,

slopes facing south and west tended to be drier than those facmg

nortli and east, moisture conditions during the period when most

of the height growth occurs (May and June) were about the same

on all aspects. Significantly better moisture conditions prevailed on

the lower slopes than on the upper, especially on the coarse, somewhat sandy banks.

Kesults from more than 30 planting experiments show little or

no differences in survival among aspects and between upper and

lower slopes. In Illinois slightly better survival of hardwoods was

found on lower slopes and northern aspects than on upper slopes

and southern aspects, but the differences were not great enough to
14 AGRICULTURE HANDBOOK NO. 166, U.S. DEPT. OF AGRICULTURE

have any practical application {30). The conifers were similarly

influenced by aspect, but their position on the slope had no effect

on their survival.

ï'urtherniore, all the.se experiments shoAv rather conclusively that

exposure (aspect) has little effect on height (,a-owth. This is perhaps due to the fact that severe drouo;hts rarely occur in the region

during the period of greatest growth in early summer. Differences

in height growth of trees planted on upper and lower slopes have

on the other hand been highly significant on some banks and not

significant on others. The erratic behavior of tree growth on upper

and lower slopes shows that factors other than position on slope

also influence growth ; the most important of these other factors are

erosion, texture, and aggregation. Striking similarity in total

heights for different exposures on the one hand and erratic response

among different topographic positions on the other, were brought out

in studies (13) of 11 species planted on 11 strip-mined areas in

Kansas and Missouri (table 3).

TABLE .3.—Six-year height growth of 14 impedes by aspect and topographic

position on strip-mined areas in Kansas and Missouri (13)

Species

Topographic position

Ridgetops Bottoms

Aspect

North and

east

South and

west

Black locust

Virginia pine

Loblolly pine

Green ash

Eastern redcedarPitch pine

Bur oak

Black cherry

Jack pine

Black walnut seed

Bur oak seed

Ponderosa pine

Sycamore ^

Shortleaf pine '

Feet

14.

5.

5.

5.

2

7

5

4

4. 6

4. 2

Feet

21.

5.

4.

5.

5. 4

3. 9

3. 8

5. 3

4.7

Feet

17. 5

5.9

7.0

5. 7

5.0

5. 4

4. 3

4. 2

3.9

2. 7

3. 3

2. 7

7.0

4. 2

Feet

17.8

5.9

5.8

6.2

5. 1

4.4

4.3

4 3

3.7

2.8

3.0

2.7

7.9

3,8

1 Planted in 1948, 5-year growth.

A survey of older plantations (15-2;") years) in Indiana confirmed

the results obtained in the younger plaiitations on the experimental

areas (17). In this survey it was also found that the total height

of the banks (relief) had a significant effect on the growth of trees

planted on the upper slopes and ridgetops, and that the differences

were greater on coarse, sandy soils than on silty, clayey soils.

From these results it appears best to classify topography of ungraded banks for tree planting simply on the basis of relief. Only

two relief classes need to be recognized: (1) Upper slopes, which

include the ridgetop and the upper two-thirds of the slopes; (2)

lower slopes, which include the lower third of the slopes and the
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 1 5

bottoms between slopes. If the average relief is less than 15 feet,

the entire area may be classed as lower slope. The bottoms between

ridges are, as a rule, slightly better sites than the lower slopes, but

the amount of area in bottoms is generally so insignificant that a

separate classification of bottoms seem impractical.

On some of the poorly drained, U-shaped bottoms that are covered intermittently by water, survival and growth have been very

poor (13). These bottoms, sometimes easily detected on old banks

by a dense cover of cattails and other aquatic vegetation, could very

well be omitted in planting (fig. 7).

VEGETATION

Although most strip-mined areas to be planted are barren, vegetation does exist on some strip-mined land at the time of tree planting. This can be both beneficial and detrimental. If not too dense,

natural vegetation helps protect seedlings from drying winds, improves soil conditions, and reduces losses from erosion. On the

other hand, natural vegetation competes Avith planted trees for soil

moisture and nutrients. Depending upon the species to be planted,

natural vegetation may permit too little, too much, or just the right

amount of light for good survival and growth. Its evaluation and

control are therefore important aspects of reclamation planning.

In preplanting surveys two broad classes of vegetation are generally recognized: (1) Ground cover, which includes all weeds,

grasses, shrubs, and tree seedlings; and (2) croum cover, which includes the larger trees. For tree planting on strip-mined land, only

two classes of ground cover need to be recognized: (a) Heavy,,

which completely shades or overtops 50 percent or more of the

planted seedlings during the first growing season; (b) light^ which

completely shades or overtops less than 50 percent of the planted

seedlings during the first growing season. Three classes of crown

cover should be considered: (a) Light, less than 10 percent of the

ground shaded by overhead cover; (b) moderate,, 10 to 75 percent

of the ground shaded by overhead cover; (c) heavy, more than 75

percent of the ground shaded by overhead cover.

Mortality and growth on sites with heavy ground cover will vary

with the density and character of the cover, Aveather conditions, and

species planted (fig. 8). Dense cover also encourages high rodent

and rabbit populations.

Two experimental areas in one locality in Illinois planted in 1947

serve as demonstrations of the eiïects of vegetation. One area supported a sparse, light ground cover, the other a dense, heavy coyer

of sweet clover. The average second-year survival of 17 species

planted was 61 percent in the light cover and only 27 percent m

the heavy cover. Ash and eastern redcedar were the only species

tested that survived well under the dense clover. The other species

planted in this test were black locust, cottonwood, yellow-poplar,

loblolly pine, jack pine, black walnut seed, black walnut seedlings,

eastern white pine, Osage-orange, red pine, shortleaf pme, silver

maple, Virginia pine, pitch pine, and SAveetgum.
16 AGRICULTURE HANDBOOK NO. 16 6, U.S. DEPT. OF AGRICULTURE

F-48in8, 485125

FiriTRE 7.—Yellow-poplar: .4, Oii loose banks, growth is generally much faster

in bottoms than on the slopes; B, on loose banks with poorly drained bottoms,

growth is better on the slopes.
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 17

FIGURE 8.—A dense stand of sweet clover has greatly retarded the growth of this

4-year-old Scotch pine.

The effect of crown cover on the survival and growth of underplanted trees likewise depends upon the character and density of

crown cover and the species underplanted. "Where the crown canopy

is composed primarily of leguminous plants, such as black locust,

these plants improve growing conditions by adding nitrogen to the

soil. This is brought about by nitrogen-fixing bacteria associated

with the root development of these species (12). A dense overhead

cover of any species, on the other hand, lias an adverse effect on the

survival and growth of most species underplanted. The response to

these environmental conditions varies according to the tolerance of

the underplanted species to shade and to their nutrient requirements,

particularly of nitrogen.

ORIGIN OF BANK "SITE"

Although it is important for the practitioner to be familiar with

the various site conditions that influence tlie survival and growth of

planted trees, it is equally important that lie know how tliese conditions came about. Site'conditions on strip-mined land depend in

general upon four things: (1) Parent material of the surface layer,

(2) methods of mining, (3) wliether or not the banks were graded

after mining, and (4) extent of erosion.
18 AGRICULTURE HANDBOOK NO. 16 6, U.S. DEPT. OF AGRICULTURE

PARENT MATERIAL

The parent niiiterial of soils developinfï on strip-mined land consists of one or more of tlie strata overturned in the minino; operation. Althoiijrh the surface of the Ijanks may be a random mixture of many of these strata, usually materials from only one or

two predominate. The future productivity of the land depends to

a great extent upon which strata provide tlie materials. Each differs from the others in physical and chemical properties, and therefore contributes different characteristics to l)ank surfaces (tables 4

and 5). The important differences are in acidity, soil texture, structure, rates of weathering, erodibility, and the relative amounts of

soil and stone.

Detailed physical and chemical analyses of individual strata in

several high walls adjacent to some strip-mined land in Illinois

were made by Thurn (JtO). His data indicate the wide variation in

physical and chemical properties among dilî'erent strata (table 6).

The data presented in this table do not represent average stratigraphic and bank-surface conditions in the region. Variations of

both are so great for each coal seam and locality that they cannot

TABLE 4.—Comparison of high-wall strata and bank characteristics 2

years after stripping, Harrison County, Ohio

HIGH WALL,

(Exposed overburden in final cut adjacent to banks)

Strata (top to bottom) Thickness Acidity Available

phosphorus '

Available

potash '

Topsoil _ .

Feet

1

3

15

1

27

3

1

20

6

pH

5. 9

5. 6

6. 6

5. 8

5. 2

Low

...do

Medium

_-_do

High

Medium

Low

Low.

Subsoil - Do.

Shale, clayey Do.

Do.

Limestone Do.

Shale - Do.

Coal, shaly _ . . Do.

Limestone

Shale 7.0 Low Do.

BANK SURFACE (4 samples)

Texture Acidity Amount of

stone '

Available

phosphorus

Available

potash

Clay

Clay

Clay

Clay

pH

6. 4

7. 6

7. 9

6. 7

Percent

44. 2

42. 2

50. 0

43. 0

High___.

Low

.__Do__.

Medium

Low.

Do.

Medium.

Low.

' As determined by extraction methods published by Arnold and Kurtz (/)•

2 As determined by extraction methods published by Bray (9).

' Based on ovendry weights.
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 19

TABLE 5.—Comparison of high-wall strata and bank charaderistics 2

years after strippin¡i, Columhiana County, Ohio

Hir.H WALL

Strata (top to bottom) Thickness Acidity Available

phosphorus

Available

potash

Topsoil

Subsoil

Feet

1/

l'"

1

5

13

22

pH

6. 3

5. 2

4. 7

4. 5

5. 8

6. 1

Medium

-_.do

Low

.-_do

Medium

High

Low.

Do.

Outcrop, coal Do.

Clay

Sandstone -. _. .

Do.

Do.

Shale Do.

BANK SURFACE (4 Samples)

Texture Acidity Amount

of stone

Available

phosphorus

Available

potash

Clay

Clav loam

Clay

Clay loam

pH

6. 2

6. 4

6. 4

Percent

61. 0

82. 0

57. 0

56. 0

High

_^.do

Medium

Low.

Do.

Do.

be presented fully here. I)et:\iled descriptions of these variations

have already been published {13. 17. 26. 27. 30. 32. 33. 3i. 37, Ji.5).'

An appraisal of these parent materials should therefore be a part

of any survey made to determine reclamation procedure. They can

quite often be isolated and sampled on bank surfaces. But usually

the most convenient place to do this is in the last cut or hi<ïh wall

separating stripped and unstripped areas (fi<r. 9). In these locations each stratum in the overburden can be identified, sampled, and

studied separately. These studies may also reveal ways to modify

current and future operations so that hijihly acid strata can be

buried and fertile materials (such as loess and calcareous shale) can

be placed on the tops of banks. The followino; descriptions of strata

commonly occurring on land strip mined in the (^entrai States are

given chiefly to aid the practitioner in evaluating sites for tree

planting.

Limestone

An abundance of limestone on bank surfaces generally means

favorable chemical reaction and high productivity. Limestone may

occur in the overburden in forms ranging from thick, massive strata

to small grains or nodules in other strata. Although it varies in

]iardne.ss, limestone usually weathers rapidly upon exposure to air

on bank surfaces. Unless "mixed in the stripping process with hard,

slowly weathering shales and sand, the soils formed from limestone

strata are almost invariably compact, plastic, cloddy clays.

513374 0—60-
20 AGRICULTURE HANDBOOK NO. 166, U.S. DEPT. OF AGRICULTURE

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FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 21

FIGURE 9.—High walls formed by strip mining are often good places to study

overburden characteristics.

Sandstone

Sandstones are commonly fonnci in strata overlyinn; coal seams.

They vary greatly in hardness and weathering characteristics. Some

are so liard and massive that they mal^e stripping difficult, whereas

others may be so soft that they can be crumbled between the fingers.

The hardness and chemical reaction of sandstoiie depend chiefly on

the kind and amount of material cementing the quartz particles together. The principal cementing materials are silica, calcium carbonate, hydroxides of iron and aluminum, calcium sulfate, calcium

phosphate, calcium fluoride, and barium sulfate (J5). There are,

then, siliceous, calcareous, and ferruginous sandstones, and their

chemical reaction depends mainly on which of these binding materials predominates. "Weathering rates are similarly affected; "Calcareous cements dissolve easily, iron cements dissolve less quickly

and easily, and sandstones with siliceous cements, especially the

quartzites, are very resistant to weathering" {19).
22 AGRICULTURE HANDBOOK NO. 16 6, U.S. DEPT. OF AGRICULTURE

The relative amount of sand and sandstone on the surface of banks

preatly influences the texture, structure, and consistence of the soils

formed. Soils containing; a hi^ïh percenta<re of sand have low waterholdinp^ capacity and hiph inñltration and drainage rates. Mixed

with silts and clays, sand makes resulting; soils more i)orous, less

plastic, and less cloddy. Except for the calcareous sandy banks in

northern Illinois, the sandy banks in the ref^ion are «generally acid in

reaction, often very highly acid.

Shale

Shales—close-grained, laminated rocks—are much more variable in

composition than the limestones and sandstones. They may be sandy,

silty, or clayey; thin-bedded or tliick-bedded. Acidity may range

from highly acid to highly alkaline, even in the same overburden.

As in other rocks, tlie rate of weathering varies according to the

hardness and cementing materials of the shales. Some are highly

weather resistant and may remain near bank surfaces for centuries.

Others are so soft that they disintegrate shortly after stripping.

With a few exceptions most of the highly acid shale occurs directly

over the coal seam. The roof coal, if shaly, is very often highly acid.

The calcareous shales connnonly occur under limestone strata, or, if

not associated with limestone, were no doubt formed by geological

processes similar to those by which limestone was formed.

Unless definitely sandy in texture, shales usually weather to clayey

soils. Tliey differ from the clay soils derived from limestones because they are generally less plastic, contain more slowly weathering

rocks, and liave better aeration and drainage than the limestonederived clays. Because of their platy, laminated structure, shaly

banks are easily planted by hand methods. The eventual acidity of

shale soils, on the other hand, is often difficult to determine, because

they usually contain more iron snlfides than the soils derived from

limestone.

Clay

Clay strata are connnon in coal overburdens. They are usually

found directly below the topsoil, limestone strata, "rider" coal seams,

or in stratigraphie positions where coal seams are expected but absent. Coals seams are almost invariably underlain by a stiff, plastic,

impermeable clay, which forms a watertight floor for lakes and

ponds in the "final cut."

Clays found directly beneath coal seams, or where coal seams are

expected, are usually highly acid and plastic; those beneath limestone strata are often calcareous but variable in plasticity. Clays

are very important constituents of bank materials; the productivity

of banks depends to a great degree upon the percentage of clay in

the surface mixture.

Loess

Perhaps no strip-mined land is more productive than that containing a high percentage of loess on its surface. Composed mainly of

silt, Avith small amounts of sand and clay and no stone, loess soils

appear to offer optimum conditions of aeration and moisture and
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 23

nutrient avaibibility for niiiny plants. SuHi soils are fjenerally neutral or calcareous in reaction. However, tliey do erode easily so, to

prevent serious <rullyin<j:, immediate revejj^etation after mining is

necessary (fio^. 10).

Thick mantles of loess are common on many strip-niinin<i- areas in

Illinois, and certain parts of Indiana, Iowa, and ^lissouri. Where

they occur, it is hio^hly desirable reclamation to modify mininij methods, if necessary, to place a large amount of loess on the surface of

the banks.

Glacial Material

Much of the strip-mined land in the country has been glaciated.

The character of glacial till is also rpiite variable. In texture it is

generally a stony sand, sandy loam, or sandy clay. Although reaction varies from highly acid to alkaline, most of the material is in

FiouRE 10.—This bank, composed mainly of loessal material, is very productive

but susceptible to severe gullying.
24 AGRICULTURE HANDBOOK NO. 166, U.S. DEFT. OF AGRICULTURE

the favorable range of pH. Because of its extreme varied character,

a carefiil appriiisal of tliis material in the high wall is desirable.

The thickness of the .soil mantle in the glaciated region varies

according to topography and the mimbei' of glaciers that have covered a given locality. In the glaciated section of the Ohio mining

region, for e.xamjile, glacial debiis is thin or altsent on the tops of

hills, and relatively thick in the valleys; glacial till is generally

thicker in the northern part of the mining region in Indiana, which

was covered by glacial material from at least two ice ages (the

Wisconsin and Illinoian), than farther south where there is evidence

of only the Illinoian glacial epoch.

Alluvium

Alluvium occurs in significant quantities only in the bottoms of

relatively narrow valleys. Most of the strip mining for coal in those

parts of the region characterized by hill and valley terrain is on

hillsides. Where mining does occur in valley bottoms, howe\'er, alluvium makes up a good deal of the overburden. It is generally fertile

material, ranging in texture from sand through sandy loam to silty

loam. Acidity conditions are usually but not always favorable.

Soil

The amount of the original soil in bank materials is usually very

small, in fact, almost insignificant. This is especially true in hilly

and gently rolling sections, where geologic erosion combined with

poor land use in the past has resulted in soil losses and impoverishment. Where soil does still exist, however, and is placed on the

tops of banks, it will add to the productivity of the land. Topsoil,

especially, contains a wealth of valuable micro-organisms that hasten

Aveathering and make the bank surfaces more fertile. Seeds and

plant parts contained in the topsoil may speed soil development.

Howe\'er, in localities where soils have been seriously eroded, growth

of trees, and even forage crops, on some banks where the topsoil has

been buriecl deeply, has compared so favorably with growth on adjacent unmined land that the value of topsoil in strip-mine reclamation in these localities has perhaps been overemphasized in some

current literature. The addition of soil to surfaces of strip-mined

land in England has in general resulted in no more plantation success than when it was not used {58).

METHODS OF MINING

Variations between high Avail and bank characteristics are due

primarily to the methods of mining employed to remove the coal.

The order in which the overburden is placed on the banks has an

important eti'ect on bank site quality and should therefore be carefully considered in reclamation plans.

ÍNIost strip mining today is done by power shovels and draglines,

used singly or in tandem (fig. 11). "The character of the material

placed on the surface of banks in stripping operations has an important bearing on the future productivity of this land. Consider, for

exami)le, the wide difference in survival and «rrowth that would be b'-
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 25

<^^.-'V.

'"^-^^ v^-*^

.->:': 1. s'

>^ ' '*',*

: ,*,'. ,.- ■■'

.1

-•^• i*'--;:..

.... • „-^:

.>•

''-ji",'' ^^"' i

- -'-¿i:>- ' 4^î^'

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/^ -/-^^

~;'i

,'«i

A>í:

«ar / ."^Sî

o-.-í"» '- S-'

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F-485129, 485127

ridURE 11.—Most of the strip mining for coal today is done with huge power

shovels {A) and draglines {B) operating singly or in tandem.
26 AGRICULTURE HANDBOOK NO. 16 6, U.S. DEPT. OF AGRICULTURE

expected between a toxic clay and a calcareous slialy loam. One

solution to the i)rol>leni is to so manage tlie strippin<r operation that

the material wliicli would make the best ])ossible medium for plant

jrrowth is placed on top of tjie l)anks. Tandem operations—where

the drap;line is located on the surface of the unmined land and the

shovel is located in tlie "pit" below—offer the greatest opportunities

to alter the order of placing different types of materials on the

banks. It is often easier, for example, to bury material from a

highly acid stratum by tandem mining than l)y tlie other common

stripping methods.

Alodii^ying mining procedures in this way increases costs, however,

and so perhaps should not be advocated except where definite and

exceptional improvement in growing conditions is needed and can

be attained. If plantable banks would result by modifying stripping procedures on banks that would otherwise be toxic, the change

in mining methods should be considered. It is desirable only in

those operations where (1) highly acid material would be placed on

the surface of banks, (2) the strata containing tho.se highly acid

materials can be identified and isolated, and (3) it is feasible to

bury all tjiis material in the banks.

GRADING

To grade or not to grade strip-mine banks is one of the most

pertinent questions in reclamation work. Required in some States

by legislation, and often motivated for esthetic reasons, it is usually

the most costly part of the job. There is no doubt that grading

plays a part in landscape improvement, Ijut, aside from esthetics, the

need for grading varies witli the intended land use. For example,

grading is desirable and usually nece.ssary for the production of

farm crops on strip-mined lands, whereas the need for grading on

lands to be planted to trees may not be of the same importance.

Some of tlie effects of grading are beneficial, others detrimental.

In the discussion following, only the effects of grading strip-mined

land on forestation are considered.

Types of Grading

Most of the grading on strip-mined laud is done by bulldozers and

draglines; on the larger operations carryalls are also used. Grading

can be classified as smootli or rough, depending on the surface

smoothness desired.

Smooth grading leaves a nearly uniform surface aiul buries large

stones; it is more expensive, and the necessarily more frequent movement of tractors and other heavy machinery over the surface compacts the soil and leaves it more impervious".

RougJi grading residts in a more uneven surface and leaves boulders on the surface. Less compaction takes jdace, and weathering

and sheet erosion .soon ameli.oi'ate the rough appearance.

Thei-e are also three general types of grading based upon the

topogra])hy desired:

CompJpte grading.—The entire stripped area except the final cutis

leveled or graded to the degree needed for the operation of farm

equipment (fig. 12). This usually leaves a gently rolling topog-
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 27

FiraiRB 12.~Mine banks graded to gently rolling topography, for production of

forage.

raphy, but it is the most expensive tj-pe of grading and results in

the most compaction of bank surfaces'.

Terrore grading.—Two or more sections of the area are graded to

different elevations, often separated by ungraded slopes. Tlie graded

sections may be level or gently sloping. On narrow strippings there

may be only one graded .section, sloping generally from an ungraded outside slope to the high wall (fig. 13).

Strike-off grading.—Only tlie tops of the ridges are graded to

widths usually varying from 10 to 20 feet (fig. U). The main

purposes of "strike-off" grading are to make the area more accessible and to flatten conical peaks of earth and serrated I'idges. This

IS the type of grading practiced on most lands to be planted to trees,

unless more complete grading is required by law.

Grading and Soil Moisture and Aeration

Experiments conducted during the past decade indicate that differences in moisture content of graded and ungraded strip-mined

land vary with the texture of tlie bank materials and become more

pronounced during periods of drought or excessive precipitation.

Preliminary tests on three different banks in Ohio disclosed a signihcantly higher moisture content in ungraded banks of heavy clay

tlian in similar graded banks after a 10-day period having less than

0.3 inch of rainfall. On banks with lighter, somewhat sandy texture,

the differences were not significant. Because of low infiltration rates

513374 O—60 5
28 AGRICULTURE HANDBOOK NO. 16 6, U.S. DEPT. OF AGRICULTURE

FinrRE 1.3.—On narrow stripping.s, the top of the shigle ridge may be graded to

slope inward toward the high wall.

F-485133

FifiuHE 14.—"Strike-ofif" grading. Only the tops of ridges are graded to improve

accessibility.
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 29

on graded banks, most of tlie precipitation was lost through evaporation and runoff. However, at the end of 10-day periods with

more than 0.6 inch of rainfall, the graded parts of the clayey banks

were wetter than the ungraded banks. This is because water percolates through graded banks so slowly that clayey banks tend to

become "water logged." On the lighter, sandy banks, no significant

diiTerences in moisture content between the graded and ungraded

parts were found at the end of these periods.

A more comprehensive study^ conducted in 1948 on three different

sites in Kansas and Ohio corroborated the results of the preliminary study in 1046 (fig. 15) (25). Two banks, one in Crawford

County, Ivans., and one in Harrison County, Ohio, had a heavy clay

texture. The other area, Columbiana County, Ohio, contained more

sand and a much lower percentage of clay. On each of the three

sites half of the area had been graded, the other half ungraded.

During the period of measurement in Kansas, there were prolonged

periods of drought and prolonged periods of much rainfall. In

Ohio, the precipitation on both areas was about normal for the entire period. The results of this study indicate that in general most

of the critical moisture conditions in the top 6 inches were due to

drought; at the 12-inch depth most of the unfavorable moisture

condition was caused by saturation.

The differences in moisture content of graded and ungraded banks

are attributed largely to differences in their rates of infiltration and

percolation. The lower infiltration and percolation rates of graded

banks are due largely to puddling, or "crusting-over" of the smoothed

surface, and to greater density and less pore space caused by the

compaction of banks in the grading operations. Several studies, carried out independently by different investigators, have disclosed an

amazing difference in the water infiltration rates between graded

and ungraded banks. In one study in Ohio, for example, the infiltration rate on ungraded banks was more than four times greater

than on the graded banks, and slightly greater than on an adjacent

old field (fig. 16). The differences reported by Merz and Finn (38)

are even more striking.

Vegetation also influences infiltration and percolation rates on

both graded and ungraded banks. On ungraded silty clay banks in

Illinois, Grandt (21) reported field percolation rates of 9.29 inches

per hour on barren areas and 1.3.57 inches per hour on areas of the

same texture but covered with vegetation for several years. For the

graded section of the same sites, the rates were only 0.89 inch per

hour on the barren part and 1.49 inches per hour on the part covered with grasses and legumes. From laboratory analyses of samples from six graded banks of similar texture but with various denzMoi.sture conditions were determined by electrical resistance methods as

devised by Bouyoucos and Mick (5). Resistance readings of 60,000 ohms or

higher at 70° F. were considered indicative of "dry" conditions and in the

range of permanent wilting of most plants. Resistance readings of 400 ohms

or less were considered indicative of "wet" or saturated conditions, and well

within the range of moisture held in excess of the so-called field capacity of

soils. The results shown are based on a total of 10,584 readings taken from 72

randomly chosen sampling stations in each of three test areas.
30 AGRICULTURE HANDBOOK NO. 166, U.S. DEFT. OF AGRICULTURE

60

50

40

^ 30 i

^ 20

I^ 60

Î

k

5

50

40

30

20

10

0

COMPACT

SHALY CLAY

CRAWFORD CO.,KANSAS

COMPACT

LIMESTONE CLAY

HARRISON CO,OHIO

LOOSE

SANDSTONE CLAY

COLUMBIANA CO., OHIO

Means for readings taken at 6-¡nch depths

Means for readings taken at 12-inch depths

GRADED NOT GRADED

DRY

WET

FinrRE 15.—Effects of texture and grading on extreme moisture conditions in

bank soils, 1918.
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 31

UNGRADED

BANKS

GRADED

BANKS

FinuRE 16.—Infiltration on graded and ungraded, strip-mined areas and an

adjacent old field, Ohio, 1945. (Tests made with a simulated ramfall device.)

sities of ground cover, Thurn (^9) found that the percolation rates

varied according to tlie amount of vegetation present from a low of

0.12 to a high of only 1.52 inches of water per hour.

Grading and Microclimate

Because grading alters the topography of a strip-mined area^ local

climatic conditions are also changed. The typical ungraded area

consists of a series of more or less parallel ridges. Only the ridgetops are exposed to drying winds from two or more directions.

Some slopes are shaded most of the day and are cool, while others

are exposed to direct sunlight and high temperatures; lower slopes

and bottoms are protected areas similar to "coves," which are so

favorable for the development of such species as yellow-poplar and
32 AGRICULTURE HANDBOOK NO. 166, U.S. DEPT. OF AGRICULTURE

blfic'k walnut. Graded Ijaiiks, on the other liand, are rehxtively uniform ill microrliniate; exposure to wind and sunlight are generally

similar over the entire graded ai'ea.

Grading and Survival and Growth of Plantations

For a given site and locality, each species responds differently to

the amount of water available for plant growth. Jack pine, for

example, may survive longer during periods of drought than white

pine. In a similar manner, some species may grow more rapidly in

saturated soils than others. Thus tliere is an upper and lower limit

of soil moisture content for the survi\al and growth of each species.

Between these limits is the range of optimum soil moi.sture conditions. The efl'ects of grading strip-mined land on the survival and

growth of plantations are related to the differences already noted

in moisture and aeration conditions.

A number of experiments involving a large number of species

have been established to study these effects, but conclusive data on

the ultimate development of plantations are not yet available. Initial survival and early growth—important factors in stand development—do, however, indicate trends. To date, these trends are the

only criteria available for comparing plantation development on

graded and ungraded banks. These results, for a number of typical

areas and species, are summarized (table 7). Differences in survival

Fir.uRE 17.—Ten-year-old white pine on a;raded banks composed of a mixture of

sandstone, shale, and clay in Colunibiana County, Ohio.
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 33

between ofraded and tnigraded parts of the two areas in Ohio, where

no prolonged droughts occurred, are not significant; the differences

for areas in Kansas and Illinois, where droughts did occur, were

significant. Height growth, on the other hand, was significantly

better on ungraded than graded parts for nearly all species on ail

areas tested.

Although some species are more adajjtable to graded banks than

others, the response will vary from one graded area to another depending upon other site factors. As an example, the average height

of white pine 10 years after planting Avas only 2.5 feet on the graded

part of one area "but (l.ti feet on the graded part of another (fi!g. 17).

TABLE 7.—Com])araiive -^urriral and total heújht oj trees planted on

graded and ungraded i^trip-mined land at Jour experimental areas in

Ohio, Illinois, and Kansas

Survival Total height

Plantation

Planting stock—

Site species and age

age class ' Graded Not

graded

Graded Not

graded

PerYears Percent cent Feet Feet

Limestone, sand- •4 Jack pine (2-0) 8 25 2. 6 2. 6

stone, shale and Eastern redcedar 51 53 2 2 2. 7

clay (Crawford (1-0).

County, Kans. ; Black locust (1-0). 72 93 10. 7 1.3.9

based on 600 trees Green ash (1-0) __. 45 59 2. 2 2. 8

of each species). Black cherry (l-0)_ 20 64 L 7 2. 1

Virginia pine (l-0)_ 20 51 2. 2 3.4

Pitch pine U-0)--- 18 43 1. 6 1.8

Bur oak seed 25 30 . 4 1.5

Sycamore (1-0) 16 54 1.6 2. 7

Shortleaf pine 34 48 . 9 1. 6

(1-0).

Limestone and clay 10 Black locust (1-0) _ 85 83 24. 2 25. 4

(Harrison County, White ash (2-0)..^ 85 97 8.8 11. 4

Ohio; based on Yellow-poplar 6 36 2.3 7. 6

1,350 trees of (1-0).

each species). Eastern white

pine (3-0).

60 67 2. 5 4. 2

Sandstone, shale, 10 Black locust (l-0)_ 97 93 29. 0 29. 0

clay (Columbiana White ash (2-0)--- 98 95 8.4 10. 6

County, Ohio; Yellow-poplar 72 72 4. 8 6. 7

based on 1,.350 (1-0).

trees of each Eastern white 90 60 6. 6 9. 0

species). pine (3-0).

Sandstone, lime- 10 Green ash (1-0).-- 83 78 13. 1 10. 8

stone, shale, and Black locust (1-0) _ 90 84 24. 3 24. 9

clay (Saline Sweetgum (1-0) — 51 66 11. 8 17. 7

County, 111.; Loblollv pine 21 61 10. 7 18. 8

based on 200 trees (1-0).

of each species). Eastern redcedar

(1-0).

62 68 11. 8 8. 7

Shortleaf pine 24 40 7.5 10. 5

(1-0).

' The fir.st number is the number of years seedling remains in nursery seedbed;

the second number is the number of years in the nursery transplant bed.
34 AGRICULTURE HANDBOOK NO. 166, U.S. DEPT. OF AGRICULTURE

Tlie first is a hifi;hly calcareous, compact, limestone, clay, whereas the

second is more acid and less compact, and is composed of a mixture

of sandstone, hard silty shale, and clay.

Conditions for plant growth are not very uniform on freshly

jjjraded l)anks. On those sections subjected to greater compacting

by the grading macliinery, growth on the "cuts" is much poorer

than on the "fills" {28).

EROSION

The susceptibility of newly strip-mined land to erosion depends

chiefly on topography and physical soil characteristics. As the

length and steepness of slopes increase, tlie amount of erosion increases. Loessal banks are highly erosive (fig. 10, p. 23). Sandy

and silty banks are more erosi^'e than tliose composed chiefly of clay.

Stone on the bank surfaces reduces erosion from raindrop splash.

Structure is also important : single-grain or granular materials

erode much more easily than cloddy materials. The formation of

flat-bottomed, U-shaped valleys, so common on l)anks consisting

mainly of soft shale, is due primarily to the ease Avith which soil

particles and aggregates are washed down the slope.

Erosion and Productivity

As erosion proceeds, soil particles and nutrients are waslied downward from ridgetops and upper slopes to lower slopes and bottoms.

Kohnke (23) has shown that alluvial bottoms have a higher pH

and contain more nitrogen, available phosphates, and available

potash than do adjoining slopes, and that the difference in nutrients decreases with depth. Soil and moisture depths are greater

on alluvial bottoms than on adjacent slopes. On highly erosive

banks, then, the productivity of the bottoms and lower slopes is

often better than on the upper slopes. So erosion accounts, at least

partially, for the differences in the growth of trees on the two topographic positions.

Erosion and Forestation Practice

Numerous planting experiments conducted on strip-mined land

have shown that mortality on the slopes may be caused by the washing aAvay of soil around the roots of seedlings (fig. 18), whereas

losses in the bottoms are often the result of siltation or smothering

(fig. 10). More losses from erosion occur on the lower slopes than

on the upper. Losses from siltation are generally much higher for

conifers tlian for hardwoods, so planting conifers in bottoms should

be avoided. Special studies in Illinois disclosed serious losses from

siltation for several species of pine, and eastern redcedar, and for

black walnut seed that was buried too deeply for good germination.

Of the si^ecies tested, black locust, ash, aiul cottonwood are the least

affected by siltation. However, to be safe, no direct seeding of any

spexMes should be attempted wliere much siltation is apt to occur.

On banks flanking silt-covered bottoms, growth of some hardwoods IS relatively poor. This is perhaps due to severe exposure of
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 35

i.--' -T* ' ■■■■■• - : - r

F-485110, 485109

FloiTRE 18.—White ash on loose, shaly, bank slope 10 years after planting.

Note: A, E.xtent of erosion in tliis "period; B, the widely distributed root

system.
36 AGRICULTURE HANDBOOK NO. 166, U.S. DEPT. OF AGRICULTURE

F-485108

Fir.uRE 19.—This 10-year-old white ash was planted in the flat bottom below

the slope (fig. 18). .\.t the time of phmting, the fork in the root at the bottom

of the picture was at the surface of the bank. Note the many adventitious

roots that have formed as a result of heavy siltatiou.

root systems, :i sliallower depth of soil for root development, low

mitrient content, and a more rapid loss of .soil-sized particles by erosion than the «jain by weatherin«; processes. On areas susceptible to

severe <;ullyin<r, an increase in the amount of lilack locust in mixed

planting:s may be helpful.

THE NET EFFECT

Althoufih the various site factors that aft'ect the survival and

«growth of trees on strip-mined land have been discussed separately,

the specific effect of any one of them usually cannot be isolated or

defined because of the combined effects of all the others. In other

words, the etiect of one factor may su])plement that of another, but

both may be counteracted by still a third. This makes it difficult

to predict just what the net eti'ect of all the site factors on a given

spoil bank will be on any one tree species. For example, in eastern

Oliio the hei<ihts of o-year-old trees planted on two different mine

])anks ran<reci from slightly more than 1 foot to nearly 23 feet dependinfr upon species, topo<rraphy, and kind of soil (fable 8).

Both areas are clayey in texture and were devoid of cover at the

time of plantinjr. However, they are different in de^rree of compactness and acidity : One is a shaly, loose, acid clay, and the other a
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 37

TABLE 8.—Ejfedn of some combinafions of site factors on the arereufe

heights of species in 5-year-old plantations on strip-mined land 'in

eastern Ohio

Species planted

White iish_ _ .

Yellow-poplar

Black locust.-

Shortleaf pine

Pitch pine

White pine

Acid, loose, shaly

davs

Ridgetops

Feel

3. t

2. 7

9. 5

2. 7

:5. 4

]. (5

Bottoms

Fed

4. 5

13. 7

4. 5

3. 9

3. 3

Calcareous, compact

clavs

Ridgetops

Feet

A. 1

1. (j

17. 1

3. 5

1.9

1. 2

Bottoms

Fcci

z. I

1. 9

22. 7

3.9

1. 6

]. 3

compact, limestone, calcareous clay. There has been nnich erosion

and siltation on the shaly area; practically none on the other.

Trees in the bottoms on the loose shaly clay are much taller than

those on the ridgetops {úg. '20). Trees in the bottoms on the compact clay, on the other hand, are only a little taller (sonaetimes even

shorter) than those on the ridgetops.

It is evident then that relief classes alone cannot he used as criteria for the choice of species on lower and upper slopes. On compact clay, growth of white ash is almost as good on the upper slopes

and ridgetops as on the l)()ttoms and lower slopes. On the loose

shaly clay, on the other hand, growtli has been twice as rapid on

the bottoms as on the upper slopes. Sorting out the factors accounting for these ditierences in height growtli on the two sites, it appears

that : (1) The loose shaly clay luis eroded nniclt more rapidly than the

compact clay, has thinner surface soil, and lias lost more soil nutrients by Mashing down the slopes to the liottoms. (2) The compact

clay has greater water-holding capacity, has a lower percolation

rate, and has lost little or no soil and nutrients on the slopes by

erosion.

Seldom do two different areas have the same combination of site

factors. Very often, however, one or two site characteristics may

he dominant," or limiting. High acidity, rapid erosion, or dense

cover, for example, could ea<'h preclude the choice of a certain species

on sites that would otherwise be suitable. Soil texture may also

influence the choice of species for planting. In making reclamation

plans all important site factors should be considered, and the dominant or limiting factors determined before species are selected.

ESTABLISHING THE FOREST

To get the most profit from striji-mine reclamation, careful planning is necessary. The first question to be answered is what parts of

the areas are to" be devoted to grazing, recreation, forestry, or other

general uses. Then tree planting plans slioidd l)e coordinated with

other developments on the entire area; the intensity of grading, for

example, may vary with ai-eas to be used for different purposes.
38 AGRICULTURE HANDBOOK NO. 16 6, U.S. DEPT. OF AGRICULTURE

^^^ê^^^^M:^$^MlÊm^iÊm

F-485119, 485107

Fir.uRE 20.—Ten yoars after planting: .4, On compact, calcareous limestone

clay, white ash on the ridgetops are almost as tall as those planted in the bottoms; B, on loose, acid, shaly clay, trees on the slopes are much shorter than

those in the bottoms.
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 39

Areas likely to be mined ao-ain, for coal in another seam, for clay,

agricultural limestone, mouldinrr sand, or other minerals, should not

be planted unless such crops as Christmas trees, posts, and mine

props can be <irown and harvested befoi'e restri])pin<i is beoun. The

location of proposed hi<>h\vays, roads, lakes, and oilier developments

should be mapped and excluded from the plantino; area. (îradin«!;

should be completed before detailed site evahiations and ])lantinii

plans are bejiun. Often adjacent old ñelds are ])lanted in the same

year as the stripped area; for frreater efficiency, crew ori>anization,

overhead, transportation, and care of stock in both operations should

be coordinated. The construction of access roads is hiohly desiraljle.

Properly located, they reduce cost of plantin«; and provide more

efficient plantation mana<>-ement and protection.

NATURAL FORESTATION

If adec[uate stands of forest trees would de\elop naturally on

typical strip-mine banks, there would of course be no forestatioii

problem. But so many elements are ao;ainst tliis ha])])enin<i' that very

few banks have ever been successfully forested in tliis way. First,

unless there is a «jood source of seed close at hand, very little if any

voluntary vej^etation will develop. Then, the site conditions found

on most mine banks are certaiidy not conducixe to the lodcinir and

germinating; of seed. Excessive rockiness of some l)anks and the

smooth, pavementlike surface of others often make it difficult for

seed to lod>ie ñrmly enoufrh to sprout and take root. And if seed

does ttnd a <rood restino; place, erosion is likely to wash it away or

cover it. As a result, volunteer veo;etation, if it occurs at all, is

often more abundant on the bottoms between rid<j;es than on the

slopes.

What natural seedin«;: that does occur is done by wind action, so

the light-seeded species such as sycamore and cottonwood are the

ones most likely to invade mine banks Hrst (hg. 21). On one 2-yearold strip-mine bank that was directly below a forested slope and

not more than 120 feet from the seed source, Merz and Plass (39)

found more than 8,000 seedlings per acre, chiefly sycamore, sugar

inaple, elm, yellow-poplar, and white oak.

At best, however, naturally seeded forests on strip-mine banks

are of doubtful commercial value. One natural stand on stripped

land in Indiana a])peaied very jjromising before a detailed inventory was conducted (17). The age of the trees varied from 1 to 30

years; scattered openings in the stand indicated revegetation was

still taking place. Averaging 4,(;ol trees per acre, this stand composed of hardwoods common to the region, included 4,r)Sl) seedlings

and saplings less than 4.5 inches in diameter at breast height, o7

poles 5 to 10 inches in diameter, and 14 larger trees. However, only

20 percent of the seedlings were desirable species, and those were

poorly formed. The sawtimber amounted to scarcely more than

1,000" board feet per acre and was of IOAV quality, not marketable

under current economic conditions.

A natural stand of sycamore on a strip-mined ai-ea in Oliio aj)-

pears to be little more promising (fig. 22). The trees. It; to 18 years

old, average 55 to 65 feet in total height and 5 inches in dnimeter
40 AGRICULTURE HANDBOOK NO. 166, U.S. DEPT. OF AGRICULTURE

Fifit'RE 21.—Cottonwood and sycamore are among the first tree species to invade

strip-mined land.

F-485106

FiGURK 22.—Natural stand of sycamore, 16-18 years old on strip-mined area

in Ohio. When good, natural stocking is evident within 2 years after stripping,

no planting is necessary.
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 41

at breast lieifïlit ; the density raiifres from 1,500 to -i,5()0 stems per

acre. However, even thouofh many of these trees are straiííht and

of good form, this stand cannot compare fa\-oral)ly in vohurie with

plantations on strip-mined hmd. Tlie average hasiil area is only 45

sqnare feet per acre, compared with tlie 90 to 120 S(piare feet"^ for

some plantations of this ao-e.

It is very evident tlien that ai-titicial forest at ion is the only sure

way to establisli fully stocked stands of desiral)le species on stripmined land (tig. 23).

F-485105

FiouRE 23.—This land was stripped for coal 35 years ago. Twenty years later

the area on the left was planted to shortleaf pine; the bare area on the right

has not been planted.

ill

DIRECT SEEDING

On the surface, direct seeding would appear to he the easiest and

cheapest way to artificially establish forests on strip-mined land.

However, comprehensive tests made during the past decade have

shown chances of failure to be so great that direct seeding is risky

at best. Although there are some examples of successful direct

seeding on strip-mined land, notably black walnut in Kansas (fig.

24) and to a lesser extent bur oak, this method of getting forests

started does not appear practical. For the best and most consistent

results, planting seedlings is recommended. A few statistics will

confirm this.

In 1947 seeds of black walnut, black cherry, and bur oak were

sown on 13 different sites in Missouri, Kansas, and Oklahoma. The

black cherry seeding was a complete failure. Six years after sowing the average survival for all sites was only 15 percent for black
42 AGRICULTURE HANDBOOK NO. 166, U.S. DEPT. OF AGRICULTURE

FioTiRE 24.—Stands established by direct seeding, such as this '20-year-old black

walnut stand in Kansas, are rare.

walnut and 24 percent for bur oak. Another sowing of black walnut seed in Kansas in 1950 resulted in 82 percent survival at the end

of 2 years. In still another study, l)lack walnut seed sown on 10

different sites in Illinois in 1947 varied in second-year survival from

6 to 67 percent, with an average of 31 percent. Tests made in

Ohio with 11 différent species on four sites also gave disappointing

results (table 9). Most direct seeding failures are caused mainly by

(1) drying out of germinating seedlings, (2) mice and other rodents

pilfering the seed (8), and (?>) erosion and siltation.

TREE PLANTING

The success of any planting on any given site is greatly affected

by (1) species planted, (2) quality of planting stock, (3) season of

planting, (4) method of planting, and (5) spacing. A wrong decision in any of these matters is perhaps more serious in strip-mine

planting than in ordinary held planting. In addition to considering

the site conditions just discussed, the prospective planter should consider each of these points carefully before beginning to plant.

Choosing the Species

After evaluating site conditions, perhaps the most critical question confronting the grower is what species to plant. To be considered are these important items: Climate; insects and diseases;

and seed sources, hybrids, and varieties.
rORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 43

TABLK 9.—Germination and first-year surriral after direct seedimj on

strip-mined land in Ohio, by s])ecies and site

Species

White ash

Black locust

Jack pine

Pitch pine

Black cherry

Shortleaf pine —

Loblolly pine

Eastern redcedar

Sycamore

Bur oak—

Black walnut

Germination

Calcareous

clav

North

slopes

Percent

0

17

10

22

. 5

12

2

5

2

50

33

South

slopes

Percent

0

15

21

13

0

6

3

0

0

48

43

Acid, shaly

clav

North

slopes

Percent

0

4

8

13

0

4

2

0

0

66

11

South

slopes

Percent

0

3

6

4

0

4

3

0

. 3

66

26

Survival (seed sjjots willi

one or more seedlings)

Calcareous

clav

North

slopes

Percent

0

20

22

30

0

18

8

0

17

50

33

South

slopes

Percent

0

22

40

22

"o

10

8

0

0

48

43

Acid, shalv

clav

North

sloi)es

Percent

0

I

1

0

0

0

CO

12

South

slopes

Percent

0

. 7

1. 5

2. 5

0

. 4

. 4

0

0

58

39

Climate

Climate, of course, definitely limits the species that can be grown

in any particular area. As a general rule, a species should not be

planted on banks out of its natural range unless the climate of the

area is very similar to that of tlie natural range. Some of the important elements that affect climate are latitude, elevation, nearby

bodies of water, and topography (54). They nmst be considered

when planning to translocate a species.

Many attempts to plant trees out of their natural climate have

failed." For example, shortleaf and loblolly pines usually have at

least a 50-percent survival when planted within their natural range.

However, when these species were planted on mine banks^ in northern Illinois and Indiana, less than 10 percent survived. Translocating tree species out of their natural range not only exposes them to

weatlier conditions to which they are not adapted, but it also makes

tlieni more susceptible to damage or destruction by insects and

diseases.

Insects and Diseases

Some tree species are more susceptible to disease and insect damage tlian otliers; and this susceptibility varies to .some extent in each

localitv. So one of the first considerations when selecting a species

to be planted on an area is its relative chance of escaping serious

damage, flave there been any recent infestations or epidemics m

the vicinity that would discourage planting of a certain species^

Is the species particularly susceptible to a specific insect or diseased

These questions should be answered before a final selection is made.
44 AGRICULTURE HANDBOOK NO. 166, U.S. DEPT. OF AGRICULTURE

F-258433

Fir.TîRE 25.—Black locust stem seriously damaged by the black locust borer.

Xo species is entirely immune to such attacks, but some species m

some areas sustain more tlian tlieir share of damage. To date only

;v few species on strip-mined hind have sustained serious losses from

diseases or insect attacks.

Tlie locust borer {MegaeyUetie rohiniae (Forst.)) is no doubt the

most serious pest on strip-mine plantations in the region. The host,

black locust, has been planted extensively and is usually seriously

damaged by borer attacks within 10 years after establishment. On
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 45

some sites, however, more of the trees could be utilized than is

generally realized, if they were cut as soon as they reach post or

mine-prop size. On some banks in Ohio tliat are not too compact

to allow good aeration, ncn- too loose to res\dt in serious ei-osion, for

example, suitable black locust posts are produced in S to 10 years.

In 12 to l.*! years, however, these trees l^ecome so seriously damaged

by the borer that they are no longer suitable for posts or mine props

(fi?. 25).

\oung shortleaf pines are often defoliated by sawflies [Neodiprion

spp.) and at the time of infestation appear to be killed. Fsually,

however, recovery has been good, witli no serious deformity or loss

in subsequent growth. Some young red pine ])lantations in eastern

Ohio have been so seriously attacked by the European ])ine slioot

moth {Rhyacionia huoliaim Schitf.) that tliis tree species is not recommended in this locality (ñg. 26). Tlie larvae of this insect are

killed by temperatures below -18° F., particularly in regions wliere

deep snows do not provide protective cover (15).

Ponderosa pine was found to be particularly susceptible to a

needlecast fungus on strip-mined land in southeastern Kansas ( ] >) ;

18-year-old plantations of this species in tliis locality—far to the

east of its natural range—were completely destroyed by this fungus.

The cedar blight, caused by Phomop-vf: juniperovoni Halm, has also

caused serious losses in young redcedar plantations.

Sometimes mammals damage planted trees. For example, on some

strip-mined land yellow-poplar saplings are seriously danuiged In'

/^-

FiGUHE 26.—Nearly every tree in this red pine experimental planting on stripmined land in Ohio has been seriously injured l)y the European pine shoot

moth.
46 AGRICULTURE HANDBOOK NO. 166, U.S. DEPT. OF AGRICULTURE

(lie coniiiion woodclinck {Mai'inotn. iiionax). Basal scars caused by

the ^niawiiii; of these rodents expose the inner bark and sapwood to

insects and fun<:i ; frequent <>;na^vinfí of the same tree often results

in defect reseinblin<i; a typical fire scar (ñ<í. '^7).

Seed Sources, Hybrids, and Varieties

A knowledjre of seed source or the availability of superior varieties and hyl)iids of desired species is important in plannin<>' a forestation ])i'oject. Oidy a few seed source or pro<reny tests have so far

been established on strip-mined land. Tlie results of tliese studies

at tiiis early date can serve oidy as prelimimiry fluides in the current j)lantin^ programs; tliey do, howevei', illustrate the potential

1% -Í f:^

F-486102

FIGURE 27.—Yellow-poplar is often severely damaged bv woodchucks. In this

tree the damage, continuing for a number of years, has resulted in a defect

resembling a fire scar.
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 47

benetits that may be <>'ainecl by applying; new findings in tliis field

of researcli.

In a test of IT difi'erent sources of jack pine from the Lake States

phmted on stripped land in Indiana, second-year survival and <j;ro\vth

of seedliufis from two sources—one from northern Wisconsin, the

(;ther from central Wisconsin—were far superior to that of others,

(xi'eat variations in fifth-year survival and growth have been noted

in a test of âO clones of hybrid poplars planted on strip-mined land

in Ohio. Average survival varied from 47 to 97 percent, while the

range in average total height was 3.8 to 11.1 feet (fig. ^H).

What does all this mean'í Simply that in the future we may have

a better knowledge of seed source and a wider selection of hybrids

and varieties suitable for specific site conditions and localities. This

will greatly reduce the risk still inherent in any strip-mine planting

operation.

F-485101

FinuRE 28.—Heights of variovis hybrid poplars on strip-mined land in Oliio

ranged from approximately 4 to 11 feet 5 years after planting.

Planting Stock Quality

The success or failure of a planting operation depends to a great

degree upon the quality of stock used. Because tlie development ot

planting stock varies greatly among nurseries—and with difterent

seasons in the same nursery—age alone is not an indicator of stock

quality. In the Central States, moreover, plantable stock ot many

species commonly planted is produced in one growing season.

Stock quality should be judged mainly on the basis of size and

balance. Stem diameter, and length and weight of roots m relation
48 AGRICULTURE HANDBOOK NO. 166, U.S. DEPT. OF AGRICULTURE

lo leiiiitli ¡UKI \vei<ilit of .shoots are generally considered the best

criteria for judginii stock quality. Root and top pruning, a common practice in nursei'ies to ada])t seedling size to various methods

of ])lanting, also affect stock quality.

Only a few specific studies have been made to determine grading

staiulards in tlie region. Chapman (//) in studying shortleaf pine

found that greater stem diameters meant better survival. Similarly,

yel]o\v-])oplar sur\ival increa.sed progressi\ely as stem diameter increased from ;>/-" to 0/^" inch (Jl). Survival declined in seedlings

larger tlinn this (liat liad been root pruned to S-inch lengths (fig.

- *)•

Top pruning has no significant effect on survival of yellow-poplar

or, a])parently, other hardwoods. And ])acking and shipping are

often cheai)er if hardwood seedlings are top pruned just after lifting

in the nursery. Moreo\er, more top-priuied trees can be carried in

planting trays.

In most planti)ig operations rcjots are pruned to standard lengths,

varying with the methods of planting employed. Roots are sometimes pruned to maximum lengths of only 6 inches when planting

bars are used; 8 inches when mattocks are used; and sometimes 10

inches when long-bladed grub hoes are used. Because the balance

-^ 100 ¡H Tops pruned to 5 inches

100

§

1 1 Tops not pruned

JS^ 90. 90

Q,

^ Ö°-

"

.80

'^ 1 ^H ::

ct: 70 ^ ^H 1 : 70

5i ^^1 ^^rr—

«0 m^ ^H ^1 ^1

Ct 60. H H i H^;;ii H .60

'Í : ^^1 ^^1 ^^1. :-. ^^1.

kj ^^H ^^H ^^H .'..": ^^1 - - V 50. ^H ^H ^H::: - ! ^1. 50

Ci ^H ^H ^H:í:Ií::í ^B ' ' ^ : ^1 ^H ^H::;::::: ^1

^ '*°- H H ; H'^;c^ H u40

Uj ^^1 ^^1 ^^1 '..:. ^^1

«^ H ^^H ^^1 ^^H ^^H:::::;:; ^^H ....

30 ^^1 ^^H ^^H:::.;::: ^^H - ^n

kj ^^B ' ^ ^^1 ^^H ^^H;;:::::: ^^1 ?S ^1 ^|: ^1';:;::!: ^1 - 5 20 I

H H' Hi^^H^: : 20

kj 1

^^1 ^^H ^^H::...::: ^^1

s: ^^1 ^^H. ^^H:::::::: ^^1

^ 10. 1 1 1 1 ^^H:-:'::-: 1

.10

3/20 4/20 5/20 6/20 7/20 Averog e

STEM DIAMETER CLASS (Inches)

Fir;rRE 29.—Second year survival of 1-0 yellow-poplar seedlings as related to

top-i)runing and stem dianieter classes. Roots pruned to maximum lengths

of 8 inches just before planting.
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 49

of physiological processes is involved, tlie degree of root-pruning

may greatly affect initial survival. Root systems of seedlings severely root pruned may not develop sufficiently before the onset of

dry weather to supply water when transpiration losses are higli.

To be accepted by practitioners, stock grading standards should

be simple and easily applied. Grading stock is an expensive and

time-consuming job. So if it is found that 80 percent of the stock

meets the prescribed standards, grading is unnecessary. Tlie planting stock grades recommended for species conuiionly planted on stripmined land in the Central States are based on specific studies and

on stock measurements taken from trees planted on more than 30

experimental areas well distributed throughout the region (tables 10

and 11). P'or conifers the standards are based on steni diameters

(at the ground line) and tlie relation of top lengths to root lengths

after pruning. For shortleaf pine, for example, the minimum stem

diameter recommended is 3/'2(lths of an inch; if roots are pruned to

()-inch lengths, the tops should be longer than two-thirds the length

of the roots (4 inches) and shorter tlian (S inches. For hardwoods,

the standards are based only on stem diameters; maximum stem

diameters are prescribed only if roots are pruned to lengths of 8

inches or less.

Care of Stock

Daily delivery of stock from the nursery to the planting site is

ideal. Because of efficiency, costs, and available transportation, however, this ideal is rarely attained. Planting stock is usually shipped

from nurseries to planting sites by railway express or truck. Shipments by freigilt should never be made. When sliipments are made

by truck, special precautions should be taken to protect the stock

from exposure to sun and drying winds. In an open truck, planting

stock should be covered completely by a canvas or plastic tarpaulin.

T.\BLE 10.—Plantimj stock (iraden for conijers planted <»i strip-mined

land in the Central States

Species

Shortleaf pine

Jack pine

Red pine

Eastern white pine

Pitch pine

Virginia pine

Loblolly pine

Eastern redcedar.^

Minimum

stem diameter at

sronnd line

Inrhes

3/20

2/20

3/20

3/20

3/20

2/20

2/20

3/20

.\llowable range in lengths

of tops

If roots are

pruned to C

inches

Inches

4-8

4-6

4-6

4-8

4-8

4-6

4-6

4-6

If roots are

not pruned

shorter than

8 inches

Inchfs

6-12

6-12

6-12

6-12

6-12

6-12

6-16

Ü-12
50 AGRICULTURE HANDBOOK NO. 166, U.S. DEPT. OF AGRICULTURE

TAHLE 11.—I'lantiiuj stock f/rades for luirdvMod plantiruj on strip-miiud

land in the Central States

Species

Stem diameter at ground

line

Maximum

Minimum (if roots are

pruned to 8

inches or less)

Inches Inches

2/20 7/20

3/20 8/20

3/20 8/20

3/20 8/20

3/20 8/20

3/20 8/20

2/20 7/20

4/20 7/20

5/20 7/20

Ash, green and white

Cottonwood

Maple, silver

Oak, bur, northern red, and chestnut

Osage-orangc

Sweetgum .

Sycamore

Walnut, black ,

Yellow-poplar

Stock should l)e jjlanted as soon as ])ossil)le. If it is necessary to

keep stock for .3 or 4 days l)efore plantinfr, moisten the iniopened

bundles or crates and store in a cool, shaded ¡dace. For longer ])eriods,

the bundles and crates should be opened, inspected, and moistened,

and the trees carefully heeled-in, or repacked and held in cold stora^ie at U° to ;^>8° F. '

If the correct temperature is maintained constantly and if the

proper precautions are taken, stock of most species can be safely

held in cold stora<re for at least '.'> weeks. The bundles or crates

should be opened at weekly intervals and the stock moistened but

not soaked. The bundles of stock or crates should be placed separately on shelves so that each can be removed without lifting the

others; they should be so arranged that the stock held in storage

longest is withdrawn for planting ñrst.

Planting Seasons

The best time of the year for planting strip-mined land in the

Central States is in late winter and early spring. Depending on

weather conditions, planting may begin anytime from the last week

HI February to the middle of March and" should be completed by

May 1. Where cold storage is available, the normal planting season may be extended safely for 2 or 3 additional weeks.

Fall planting usually results in much loss from frost-heaving. In

tests made by Chapman (10) the average survival and total height

of shortleaf pine planted on stripped land in Ohio, 7 years after

planting, were 38.6 percent and S.(; feet for fall-planted stock in

contrast to !)5.() percent and 11.0 feet for spring-planted stock. If

fall planting is necessary to distribute job loads in large operations,

or because of labor shortages in the spring, it should be restricted

to banks least susceptible to frost-heaving such as those with moderate to dense ground cover, and to barren areas that are sands or

loose, shaly loams.
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 51

Planting Methods

Despite modern trends toward mechanization, hand planting; will

probably continue to be used on strip-mined land for some time.

Plantiufr macliines have been used to a limited extent on some graded

banks that were not too stony or compacted. Such conditions, however, are rare on stripped land in the region.

There are two general hand-planting methods: (1) The slit

method, in which roots of trees are placed in slits and packed by

pressure from a bar or hoe thrust in the ground 2 to 4 inches from

the slit; and (2) the hole method, in which the tree is placed on

one side or in the center of a hole, and the roots are packed by

hand with loose material (J^O). Slit planting is faster. Planting

bars, mattocks, grub hoes, and spades are usually used in hand

planting {50). The bar is the most common tool used in the slit

method, and mattocks or grub hoes are most commonly used in hole

methods. The light, short-handled grul) hoe, sometimes known as

the "Rocky Mountain Planting Hoe,'' is becoming a po])ular tool for

planting certain types of stripped land. Used with a waterproof

canvas bag for carrying stock, it is particularly adaptable to the

rough, steep, and stony terrain so characteristic of many banks.

The choice of methods for planting strij^-mined land depends

mainly upon the physical character of the l)ank surfaces and the

type of equipment available. Tests nuide in Ohio disclosed little or

no signiftcant differences in early survi\-al and growth of yellowpoplar and white pine when planted by slit or hole methods {S2).

Large-scale plantings made by tlie bar-slit method on stripped land

in Indiana have been especially successful. If the bar can l^e easily

thrust into the ground with little or no foot pressure, it is the most

efficient handtool to use. When the ground is stony or very compact,

the mattock is best.

Planting crews of 8 to 10 planters, with one foi'eman, are recommended. Foremen should constantly check methods of |)]anting and

the condition of the trees in the planting boxes or bags. On dry,

windy days, it is especially important to keep trees moist until they

are planted. The crew should proceed in echelon (tig. oO) ; on

steep slopes, especially when there is danger of sliding rock, the

foreman should see that no planter is working directly l)elow another.

In large-scale planting o])erations a man or ci'ew specially assigned

should be trained to maintain the heeliiig-in bed or storage facilities, pack trees, and distribute them to the planting crews. This

insures proper care of stock from the time it is received to the time

it is given to the planter.

Spacing

Spacing of trees in plantations is no doubt one of the most controversial subjects in reforestation. Opfimvnn spacing varies with

such features as species, site, locality, and oltjectives. In general,

spacing should be wide enough to ])ostpone tlie first thinning until

merchantable products can be obtained, and close enough tf) nisure

good form and de\elopment. Conifers as a rule may be planted at
52 AGRICULTURE HANDBOOK NO. 16 6, U.S. DEPT. OF AGRICULTURE

FIGURE .30.—Part of planting crew, proceeding in echelon on an old strip-mined

area. Note use of bars and canvas planting bags.

slifilitl^v wider spacinps than hardwoods. No more trees should be

planted tlnm are necessary to meet the planting objectives. Experiments indicate that a spacing of 7 by 7 feet, now in general use is

perhaps the l)est for most planting on strip-mined land (7. 17). On

good sites conifers can probal)ly be planted safely at 8 by 8 feet. A

spacing of 6 by 6 may be satisfactory for hardwoods where erosion

control is a secondary oljjective.

Pure or Mixed Planting

Whether to establish mixed or pure plantations depends primarily on the species to be used, and the objectives of management.

Silvical characteristics, particularly growth rates and tolerance to

shade, and site productivity are factors to be considered. Both types

of plantings have their advantages and disadvantages. Pure plantings are easier to establish, manage, and harvest, but they are more

susceptible to damage from insects and disease. Certain hardwoods

grow faster when mixed with black locust.

In mixed pine plantations, certain species grow so much slower

than other species that they may all die before products can be harvested. Hence pure plantings of pine are favored over pine mixlures. If mixtures are desired, they slioidd consist of small groups

of rows or blocks of pure plantings. If planted in rows, groups

should consist of a minimum of 5 rows of one species, alternated by

5-row blocks of other conifers. With few exceptions (table 15, p.
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 53

60), hardwood pliintiii<is sliould consist of mixed ])l;nitiii<is, and for

some species a mixture with bhvck locust is desirable.

If a "öO-f)!)" mixture is used, the two species can l)e planted separately in alternate rows. If a mixture is to consist of 25 percent

black locust and 75 percent "other hardwoods", each row of "other

hardwoods" should be flanked \)y rows with l^lack locust planted in

alternate spots.

Black Locust as a "Nurse" Tree

Because black locust has proved to be so beneficial as a "nurse"

tree and soil improver in old-field plantations, the practice of interplantinji black locust with other species on mine banks warrants

special attention. The beneticial eti'ects of black locust in mixed

hardwood plantings on old fields have been clearly demonstrated

(7S). So far, the I'esults of planting sucli mixtures on strip-mined

land have been so obscure that acceptance of this practice as standard has at times been challenp;ed. The chief difKcidty stems from

the fact that black locust often <j;rows much faster on strip-mined

land than it does on old fields, so that it soon overtops the associated species (fig. ?>1). Therefore competition between black locust

L'ùè--<^'i::y'^irÀi!^

F-485131

Fir.uRB .31.—Four-vear-old biack locust planted on mine banl^s (background)

and on old field "(foreground) in Columbiana County, Ohio. Note difference

in height between trees on the two sites, and that crowns of trees on banks

have already closed at this early age.
54 AGRICULTURE HANDBOOK NO. 166, U.S. DEPT. OF AGRICULTURE

and iissoriiited species for lif;lit and moisture in mixed stands may

become ci'itical at a much earlier a^^e on strip-mined land than on

some old fields.

The decision whether (o use hlack locust-hardwood mi.xtures should

depend on the objectives of the reclamation j)roject. Where cover

is needed (juiclvlv to I'educe erosion, oi- where i-apid soil improvement

for frrowth of other trees is desirable, i>Ianfin<i black locust, pure

or mixed, is recommended. In dense stands of black locust, leaf

litter and orj^anic matter accumulate quickly (ñ<r. -^2), thereby impro\in<i soil aeration, increasing water iiiHltration, and addino^ to

the or<j:anic matter and niti'o^en in the soil.

Tlie beneñcial eífects of black locust on the <rrowth of some associated hardwoods are well illustrated by a ])lantinir experiment

established on a strip-mined area in southern Illinois. linual numbers of trees from the same nui'sery and seed source were planted

under a decadent black locust stand and in an adjacent open stand

of shoi'tleaf pine. Site conditions were similar at the time of the

ori<iinal planting of locust and pine. Twelve years later the meFiGURE 32.—A good cover of litter has already accumulated under this 6-vear-old

black locust plantation in Ohio.
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 55

(lian hei<xht of sevei'al species in tlie locust stand was two to three

times greater tlian in the pine stand (table 1:2). In achlition, most

trees growing in mixtures with black locust had better form (J(J).

During the past decade, many otlier experiments testing the value

of locust-liardwood plantings have been established. Success of the

planting depends upon many elements other tlian mixtures of hardwoods and black locust, all of whicli must be carefully evaluated.

These include tlie species planted, quality of planting stock, percentage of black locust used, rate of black locust decadence, site

conditions, and timing. Hy timing is meant whetlier tlie other

hardwoods are planted before tlie bhick locust or at the same time,

or are underplanted in the locust stand at a later date.

The most promising species for planting with black locust appear

to be red/and chestnut oaks, yellow-poplar, black walnut, sweetgum,

green and white ash, and sugar maple; the least promising, cottonwood and sycamore. Kedcedar is one of the few conifers tliat grows

M-ell under open black locust stands (fig. oo) until it reaches Christmas-tree size. Redcedar trees growing with and under black locust

appear to be a richer green in color during the winter than those

planted without locust, a factor worth considering in the production

of Christmas trees.

Quality of planting stock, often overlooked, is especially important where, competition with fast-growing black locust for soil moisture is great. To assure good survival, sturdy well-balanced seedlings with a minimum of root pruning should be selected (30).

'\Vliat percentage of the trees in a plantation should be black

locust? That depends on the other species to be planted, sites, and

the expected development of the black locust trees, as well as the

desired number of other hardwoods in the final stand, and whether

the owner can thin or release the plantations when necessary. SevTABLE 12.—Effect of pine and black locust on underplanted trees, 12

years ajter underplantinij

Overstory

Planting stock

species and age

Open shortleaf pine Decadent black locust

Survival '

Median

height 2

Range in

height

Survival

Median

height

Range

in

height

Yellow-poplar, 1-0

Black walnut, 1-0

Black walnut, seed

Silver maple, 1-0

Sweetgum, 1-0

Green and white ash, l-0_

Osage-orange, 1-0

Percent

68

79

3 71

63

87

84

67

Feet

9

13

10

6

13

7

7

Feet

2-26

3-23

3-20

2-13

2-23

1-12

2-16

Percent

48

73

54

64

* 21

56

46

Feel

30

32

30

18

11

8

12

Feet

1-41

3-36

4-37

6-40

3-24

1-18

6-21

aasis: 100 trees of each species planted on each site.

Half of the trees taller than median height; half shorter.

' Percent of seed spots with one or two living trees. ,„„(-;„„

* Most of the mortality caused by rabbits, within 2 years after planting.
56 AGRICULTURE HANDBOOK NO. 166, U.S. DEPT. OF AGRICULTURE

Fir.T'RE 33.—Eastern redcedar grown under open black locust stands in southern

Illinois seem to make better Christmas trees than when open grown. These

trees, 8 years old when photo was taken, were dead 4 years later; growth was

not rapid enough to compete with associated black locust and other hardwoods.

eral studies have been made involving various amounts of black

locust in strip-mine plantations. The results, liowever, have usually

been confounded by attacks of the locust borer, which have completely destroyed the locxist trees in some plantations and left them

untouched in others (ñg. o4). Nevertheless, indications are that if

too many locusts are planted (more than 50 percent of the stand),

some thinning may be necessary in 6 to 8 years provided the borer

does not open up the stand fírst.

In one area in Indiana two stands, one containing 25 percent

black locust and tlie other 75 percent, have been so badly infested

with the borer that most of the locust tops are dying and falling

down (table 13). Here interplanted yellow-popular has survived and

is growing well. In another part of Indiamx similar stands that

escaped serious borer damage developed such a compact closed canopy of locust that almost all the interplanted yellow-poplar trees

died within 11 years. ITnless no thinnings or release cuttings are

made in such stands, it is doubtful if a sufficient number of trees

will survive to form a good stand after the natural breakdown of

the black locust.
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 57

- O "^

5 g I

Ä 5"

.- o

^T3

o o

O

O (-

-^ 1> rv

¿-^ r^ 3 o C

S Ö O

»-^ +J> •"*

> - «

i; 5 t^

^^ —

? c3"C

o
58 AGRICULTURE HANDBOOK NO. 166, U.S. DEPT. OF AGRICULTURE

TABLK \'.i.—EJfect of rapid deterioration oj black locust on survival

and (jrowth oJ other interplanted species, 11-year-old plantations on

acid, silty shale in Indiana

Black locust deterioration and interplanted speciesAmount

of black

locust

Interplanted species

Survival Trees

per acre

Percent Nu mher

12 81

15 33

51 344

50 112

1 4

0 0

58 394

61 136

Height

Fast deterioration of black locust (more

than 50 percent dead tops) : Yellow-poplar

Northern red oak

Slow deterioration of black locust (less

than 10 percent dead tops) ".

Yellow-poplar

Northern red oak

Percent

25

75

25

75

25

75

25

75

Feet

21

20

21

19

10

17

7

Basis: 3 plots of 200 trees of each mixture on both sites.

Underplanting in black locust stands has been more successful

than simultaneous mixed plantings. This is probably due to improved site conditions and a shorter elapsed time from date of planting to date of natural deterioration of the locust overstory. However, success of either type of planting depends mainly upon these

two factors. Tests in stands where the black locust breakdown is

almost complete 11 years after planting show promising results for

most species (table 14). But on similar plots where the black locust

had not yet begun to deteriorate, luiderplanted yellow-poplar, sweetgum, cottonwood, and sycamore failed completely. If planting is

delayed until a dense ground cover has developed under the locust,

poor survival may result i3£).

In mixed simultaneous plantings, survival and growth of the other

hardwoods at spacings of 7 by 7 feet have been much better with

25 percent locust than with higher percentages of that species. Such

a mixture (usually one row of other hardwoods alternating with rows

having 50 percent black locust) permits a wide choice of species,

and the costs of later release are greatly reduced, if not eliminated

entirely.

Planting costs are increased, perhaps doubled, when black locust

is hrst planted and then later underplanted. In general practice,

when high-qmility planting stock of the desired species is used, mixed

sinudtaneous plantings containing 25 percent locust should give satisfactory results. Where erosion control or soil improvement is the

predominant, innnediate objective, pure plantings of black locust

appear to be the best practice. ()ther hardwoods may be planted

later when the locust is cut for posts, or when the locust is beginning to deteriorate from borer attacks.
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 59

TABLE 14.—Surviml and height of O-year-old trees planted under decadent 1Í-year-old Ktandu of .900 black locust trees per acre in Indiana

Black locust deterioration and species

Fast deterioration of black locust (more than

70 percent dead tops, 9 years after underplanting) :

Yellow-poplar

Black walnut:

Seedlings

Seed

Silver maple

Sweetgum

Green and white ash

Slow deterioration of black locust (15 percent or less dead tops, 7 years after underplanting) :

Black walnut

Chestnut oak

Sweetgum

Cottonwood

Sycamore

Survival, trees

per acre

rcent Number

30 270

70 (530

60 540

Ü3 567

57 513

80 720

88 792

82 738

0 0

0 0

0 0

Height

Feet

13

9

12

12

10

11

PLANTING RECOMMENDATIONS

The species reconinieiuled for pliuitin<r on strip-mined land in the

Central States are given in table 15. Tlie major site conditions and

the locality of tlie plantin«; areas, and the natural ranjies of the

listed species were considered in makintj: these recommendations.

All the species recommended liave been planted on many areas in

the region. The reconnnendations are based on studies of large-scale

and experimental plantings of tliese and many otlier species. Several other species, including basswood, l)aldcypress, tamarack, European and Japanese larches, and Bnisman ehn (a .selection of Tlmus

carpinifolla), may l)e snitalile for planting on some strip-mined land

in the region. Another species, European alder {Alnv-^ glutinosa

(L.) (îaertn.), appears to be a promising nurse-crop tree. ITowever,

until more information is available on survival and growtli, only

small-scale plantings of these species sliould be made.

The table is divided into two sections, according to l)road soil

texture and aggregation classes. Tlie tirst section includes species

recommended for l)anks tliat are sandy or loose loams and clays;

the second section is for banks that are composed mainly of compact

loams and clays.

The following notes may be helpful in using tal)le 15:

:^peries.—T\\e species marked by an asterisk (*) in tlie table are

preferable for large-scale plantiïig, as well as for stand development and quality of the products. Those not marked witli an asterisk are nevertlieless satisfactory, and some may be the most desirable for special products. Scotcli pine, for example, may be the

most desiralile for Christmas trees, while Osage-orange may lie the

best choice for fence posts.
60 AGRICULTURE HANDBOOK NO. 166, U.S. DEPT. OFAGRICULTURE

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62 AGRICULTURE HANDBOOK NO. 166, U.S. DEPT. OF AGRICULTURE

Tlie site re(iuireineii(s speciHed for l)liU'k locust apply only when

this species is phuited tV)i- wood production. Tliey iieed not he considered wlien this sj)ecies is desired as a mii'se crop, for soil improvement, oi- for ei'osion control.

AchViiy nnigc.—Tlie predominant pll ran<ie of tlie soil on the

area to l)e planted should l)e determined (])roced>ire described on p.

72). If toxic, tlie ai'ea is nonplantahle; if iriarffinal, only such

species as hlack locust, silver ma])le, Virofinia pine, and sycamore

shoidd I)e jjlanted, maiidy for soil improvement and erosion control.

Numl)ers in parentheses are the preferred pll ranj^es for the species;

the number l)efore the parenthesis represents the lowest pH plantable for the species; the number after the i)arenthesis represents the

hi<ihest pIT considered i)lantab]e. Maximum and minimum pH

ranjjes were determined larjrely by field observation of the species

on strip-mined land in tlie re<rion. The preferred ranjres are based

partly on these Held ob.servations and, where these are lacking, from

data reported by Spurway (If7).

Topogrdphi/.—As discussed in ii ])recedin<r section (j). l-S), topography is considered simply as the followin<i relief classes: (1)

Upper slopes, including ridgetops and the up])er two-thirds of slopes

with total relief of more than l;-> feet; ( .;) lower slopes, including

all ungraded banks with total relief of less than 1;") feet, or the

bottoms and lower third of slopes with total relief greater than 15

feet; and (?>) all graded bank surfaces. The slopes created by

"terrace" and "strike-ort" grading are classified as ungraded banks.

(rivioul carer.—As classified in a preceding section (p. 15).

FicuRE 35.—Strip-mine planting zones in the Central

States.
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 63

Crown cover.~On\y areas tliat liave li^rl,t aiul moderate densities

ot crown rover are considered plantahle. Areas with lieavy crown

cover should l,e tliinned at least (o moderate densitv within 2 years

atter plantin<r. I nderplantin<i dense, unmerchantable black locust

stands should be deferred until about 2 years before extensive dieback ot tops occurs. This can be detern.ined by close observation

ot the stands or by comparison witli otlier stands on similar sites

l>l(irl- lontsf mirfiirr.—Thh column refers to the ]-ecommended

proportion of l)lack locust to be planted witji the species. See discussion on black locnst as a "nurse" ti'ee (]>. 5o).

Sfnp-mhe planting ,;o/i^,v.—Tlie si)ecies are recommended for

planting only in the zones indicated (ti<>:. ;*,5).

GROWTH AND YIELD

Althoufrh precise yield data are available only for short-rotation

crops, there is some evidence that trees i)lanted on strip-mined land

M-ill eventually produce sawtimber as well. Tlie ajje at which these

crops can be harvested depends upon <rrowinir conditions on each

site and on the desired size of the product, (liristmas trees, posts,

and mine props can be produced in 5 to IT) years; small poles and

pulpwood can be produced in '20 to 30 years. Sawtimber will, of

TABLE 16.—Growth and rjield of IS dijferent plantations on strip-mined

land in Indiana {17)

Species Age

White pine, white spruce

.lack pine

Jack, red pine

Scotch, Austrian pine

Scotch, Jack pine

Ked, Scotch pine; black walnut- _.

Red, Scotch, Jack, white pine;

black walnut

Scotch, Austrian, rod pine; black

locust, black walnut

Scotch, Austrian, Jack pine

Jack pine

Scotch, Austrian, Jack pine; northern white-cedar, white spruce

Scotch, Austrian pine; black walnut

Scotch pine

Years

22

22

22

21

21

21

20

20

19

19

Stocking per acre

Trees

Niimlier

525

i,o:«

200

488

6:í3

8:53

1, 149

966

884

583

760

925

600

Basal

area '

Sq. file

97

97

72

51

60

112

84

93

44

108

93

74

Merchantable

volume 2 per acre

Cubic

volume

Cii. ft.

640

1, 105

1, 117

968

498

412

998

704

770

704

1, 226

1, 169

640

7!^-foot

posts

Ahimber

640

1,583

1, 533

961

733

450

1, 240

766

900

766

1, 140

1, 358

583

' Does not include intermediate or suppre.s.sed trees less than 17 feet tall, or

natural reproduction.

^ Volume of planted trees only; based upon a minimum top diameter of 3 inches,

inside bark.
64 AGRICULTURE HANDBOOK NO. 166, U.S. DEPT. OF AGRICULTURE

course, take niucli longer. A few examples will give .some indicafioii of wliat can he expected.

Tliiiiniiigs made in a 7-yciir-old black locust plantation on hanks

in Oklahoma ])roduced more than 'VPA> fence posts per acre; the

residual stand and the \igorous sprout growth that followed the

tirst cutting suggested tluit another salable crop might be harvested

after 5 more years (4-5). A lO-year-old black locust plantation in

Ohio yielded (iOO to 7(H) posts per acre. Part of a 20-year-old plantation of Scotch and Japanese red pines on mine l)anks in Indiana

was clear cut in 1!)51 to make way for expanding industrial facilities

(fig. 3f;) ; the staiul cut yielded 'À,d7-i lineal feet of posts and poles

from ().!> ai're, which sold on the market for %'-M)2. Although immature when cut, this plantatioji gave a gi'oss return of $17 per acre

per year (17).

Early growth on strip-mined land of species commonly used to

produce long-rotation cro])S (piling, sawtimber) appears quite good

(table l(i). For example, at age 20 some species of pine on banks in

Indiana were 8 to 14 feet taller than their counterparts in plantations in their native Lake States habitat (//). The growth of most

red and white pine plantations on strip-mined land in Indiana was

about equal to that on old tíelds of average site quality.

Ivogers (4-5) found on mine banks in Missouri 30-year-old black

walnut trees about 18 inches in diameter at breast height and 50

r-4S5099

FIGURE 36.—Part of this 23-year-old Scotch and Japanese red pine plantation

on strip-mined land in Indiana yielded 3,973 lineal feet of posts and poles on

0.9 acre.
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 65

feet hifili tliat liad good form and were <íro\vÍM<r fastei- than the

averag'e rate for tliis species on iinniined huid in the vicinity. Yellow-poplar trees planted on a stripped area in Indiana were attaining! small sawtimlier size at 30 years (fi<r. oT). The evidence to

date, therefore, indicates that the rotations reqnired to o;row sawtimber on mine banks in the re<iion are no longer than for many

adjacent old ñelds. Growth rates will perhaps vary more amon<i

sites on each of these two land types than between the avei'age

«rrowth rates of each.

FIGURE 37.—Yellow-poplar in this 30-year-old mixed hardwood stand on stripmined lamd in Indiana is reaching small sawtimber size.
66 AGRICULTURE HANDBOOK NO. 16 6, U.S. DEPT. OF AGRICULTURE

SUMMARY

Strip mining for roul in the Central States refjion of tlie United

States lias created a new type of land snrface, with many unique

problems related to its I'ehabilitation and use. One of the best ways

to reclaim strip-mined land is by fore.station. Most of tliis land is

suitable for the plantin<i of trees and tlie production of some forest

crops, includinjr Christmas trees, posts, mine timbers, pulpwood,

poles, and possibly pilinij; and sawtimljer. Otiier beneñts of forestation include soil and water conservation and improvements for recI'eational use.

Forestation usually means plantin^r Ijecause neitlier natural forestation nor direct seediiifr have proved to be successful ways to e.stablish forest cover on strip-mined land. The soils created by strip

mining, generally consisting of material from many rock strata

overtui'ued in the mining, are more variable and complex than normal soils derived from a single kind of parent material.

So, to grow trees successfully on strip-mined land, one nuist carefully evaluate each site and select species that are suitable. Some

of the important site factors directly aifecting establishment and

growth of trees on strip-mined land are the following:

1. Phy-'iicdl rhararferi-sfie,'! of bank maferidh.—Tliese characteristics include the percentage of stone and the soil texture, structure,

and consistency.

2. Chemietd reaction.—Acidity of bank surfaces, commonly expressed as pH, sometimes limits survival and growth of trees. A

pH of less than 4.0 generally indicates that the area is nonplantable.

3. Topography.—Exposure or aspect has little effect on early survival and growth ; but on many areas growth is Ijetter on lower

than upper slopes.

4. Vegetation ov coxier.—A dense ground cover reduces survival

and growth of many pines and some hardwoods planted on stripmined land. Overhead cover, sometimes favorable for establishment and early growth, may l)e a deterrent to later development.

These site conditions in turn are determined and influenced by

.several things, such as the parent material, methods of mining, grading, and ei'osion. In addition to the site conditions one must consider susceptibility to insects and diseases, seed source, quality of

planti)ig stock, and season of planting.

The use of black locust in mixed plantings, if carefidly planned

with res[)ect to proportions used and cidtural measures needed, will

result in better growth of many associated species, such as yellowpoplar, black walnut, red oak, sweetgum, green and white ash, and

eastern redcedar. Specific reconnnendations for planting 23 species

are listed.

Growtli and yield data for trees growing on strip-mined land are

lacking, but indications are that trees planted on such sites will

produce salable crops in as short a time as comparable old-field

plantations.
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 67

LITERATURE CITED

(1) ARNOLD, OCHARLES Y., anrl KVRTZ, TOUBY.

1946. PHOTOMETER METHOD FOR DETERMrNINfl AVAILABLE PHOSPHORUS IN

SOILS. III. Agr. Expt. Sta., Depts. A^TOTI. and Hort., Mimeo. Cir

AC! 1300, ,5 pp.

(2) ARNON, D. I., and ,JOH\SO,\, C. M.

1942. IN'FLITENCE OF HYDROCE.X ION CONCENTRATION ON THE OROWTH OF

HI(¡HER PLANTS UNDER CONTROLLED CONDITIONS. Plant Phvsiol

17: ,525-539, illus.

(3) BAYER, L. D.

1948. SOIL PHYSICS. Ed. 2, 398 pp., ilhis. New York, London.

(4) BouYoiicos, GEORCE JOHN.

1951. A RBCALIBRATION OF THE HYDROMETER METHOD FOR .MAKINO MECHANICAL ANALYSIS OF SOILS. Joiir. Afiron. 43: 434-438 ilhis

(5) and MICK, A. H.

1940. AN ELECTRICAL RESISTANI^E METHOD FOR THE CONTINUOUS MEASUREMENT OF SOIL MOISTURE I'NDER FIELD CONDITIONS Micll Agr

Expt. Sta. Tech. Bui. 172, 38 pp., illus.

(6) BRAMBLE, WILLIAM C.

1952. REFORESTATION OF STRIP-MINED BITUMINOUS COAL LAND IN PENNSYLVANIA. Jo\ir. Forestry 50: 308-314, iihis.

(7) BRAMBLE, W. C, COPE, H. N., and CHISMAN, H. H.

1949. INFLUENCE OF SPACINO ON ííROWTH OK RED PINE PLANTATIONS.

Jour. Forestry 47: 726-732, illus.

(8) and SHARP, WARD M.

1949. RODENTS AS A FACTOR IN DIRECT SEEDINC, (IN SPOIL BANKS IN

CENTRAL PENNSYLVANIA. Jour. Forestrv 47: 477-478.

(9) BRAY, R. H.

1945. PHOTOMETER METHOD FOR DETERMININO AVAILABLE PF)TASSIUM IN

SOILS. Ill, Agr. Expt. Sta., Dept. Agron., Minieo Cir. AG 1275,

9 pp.

(10) C^HAPMAN, A. G.

1944. FOREST PLANTING ON STRIP-MINED COAL LANDS WITH SPECIAL

REFERENCE TO OHIO. U.S. Forcst Serv. Cent. States Forest

Expt. Sta. Tech. Paper 104, 25 pp., illus.

1948. SURVIVAL .\ND OROWTH OF VARIOUS CRADES OF SHORTLEAF PINE

PLANTINO STOCK. lowa State Col. Jour. Sei. 22: 323-331.

(12) and LANE, R. D.

1951. EFFECTS OF SOME COVER TYPES ON INTERPLANTED FOREST TREE

SPECIES. U.S. Forest Serv. C;ent. States Forest Expt. Sta. Tech.

Paper 125, 15 pp., illus.

(13) CLARK, F. BRYAN.

1954. FOREST PLANTING P(JSSIBILITIES ON STRIP-MINED LAND IN KANSAS,

MISSOURI, AND OKLAHOMA. U.S. Forest Scrv. Cent. States Forest

Expt. Sta. Tech. Paper 141, 33 pp., illus.

(14) CoiLE, T. S.

1953. MOISTURE CO.NTENT OF S.MALL STONE I\ SOIL. vSoil Sci. 75: 203-

207, illus.

(15) CRAIOHEAD, F. C.

1950. INSECT ENEMIES OF EASTERN FORESTS. U.S. Dept. Agr. Misc. Pub.

657, 679 pp., illus.

(16) DBITSCHMAN, GLENN H.

1956. OROWTH OF UNDERPLANTED HARDWOODS IN BLACK LOCUST AND

SHORTLEAF PINE PLANTATIONS. L^.S. Forest Serv. Cent. States

Forest Expt. Sta. Note 94, 2 pp.

(17) and LANE, RICHARD D.

1952. FOREST PLANTING POSSIBILITIES ON INDIANA COAL-STRIPPED LANDS.

U.S. Forest Serv. Cent. States Forest Expt. Sta. Tech. Paper

131, 57 pp., illus.

(18) and NECKERS, J. W.

1953. IDENTIFICATION AND OCCURRENCE OF SULPHIDES ON LAND STRIPPED

FOR COAL. U.S. Forest Serv. Cent. States Forest Expt. Sta.

Tech. Paper 136, 21 pp., illus.
68 AGRICULTURE HANDBOOK NO. 16 6, U.S. DEPT. OF AGRICULTURE

(19) EMERSON, FREDERICK V.

1928. AGRICULTURAL fiEoLOfiY. Ed. 2 rev. by John E. Smith. 383 pp.,

illus. New York, London.

(20) FINN, RAYMOND F.

1953. FOLIAR NITROGEN AND OROWTH OF CERTAIN MIXED AND PURE

KOREST PLANTINGS. .Jour. Forestry 51: 31-33.

(21) CRANDT, ALTEN F.

1952. THE POTENTIALITIES OF REVECETATINn AND UTILIZING AGRONOMIC

SPECIES ON STRIP MINED AREAS IN ILLINOIS. IH. Agf. Expt. Sta.

and 111. Coal Strippers Assoc. (5th yr. prog, report), 56 pp., illus.

(22) HEIBERG, SVEND ()., and WHITE, DONALD P.

1951. POTASSIUM DEFICIENCY OF REFORESTED PINE AND SPRUCE STANDS

IN NORTHERN NEW YORK. Soll Sci. Soc. Allier. Proc. (1950) 15:

369-376, illus.

(23) KoHNKE, HELMUT.

1950. THE RECLAMATION OF COAL MINE SPOILS. Advances in Agron. 2:

317-349, illus,

(24) KRAMER, PAITL J.

1949. PLANT AND SOIL WATER RELATIONSHIPS. Ed. 1, 347 pp., iUus.

New York, Toronto, and London.

(25) LiMSTROM, G. A.

1948. EXTENT, CHARACTER, AND FORESTATION

STRIPPED FOR COAL IN THE CENTRAL

Cent. States Forest Expt. Sta. Tech.

POSSIBILITIES OF LAND

STATES. U.S. For. Serv.

Paper 109, 79 pp. Illus.

(26)

(27)

(28)

1950. OVERBURDEN ANALYSES AND STRIP-MINE CONDITIONS IN NORTHEASTERN OHIO. U.S. Forest Serv. Cent. States Forest Expt.

Sta. Tech. Paper 114, 44 pp.

1950 OVERBURDEN ANALYSES AND STRIP-MINE CONDITIONS IN MIDEA6TERN

OHIO. U.S. Forest Serv. Cent. States Forest Expt. Sta. Tech.

Paper 117, 33 pp.

1952. EFFECTS OF GRADING STRIP-MINED LA.NDS ON THE EARLY SURVIVAL

AND GROWTH OF PL.'^NTED TREES. U.S. Forest Serv. Cent. States

Fore.st Expt. Sta. Tech. Paper 130, 35 pp., illus.

(29)

1953. A BIBLIOGRAPHY OF STRIP-MINE RECLAMATION. U.S. Foiest SerV.

Cent. States Forest Expt. Sta. Misc. Rel. 8, 25 pp.

(30) and DEITSCHMAN, G. H.

1951. RECLAIMING ILLINOIS STRIP COAL LANDS BY FOREST PLANTING.

111. Agr. Expt. Sta. Bui. 547, pp. 201-250, illus.

(31) , FINN, R. F., and DEITSCHMAN, G. H.

1955. PL.ANTiNG STOCK GRADES FOR YELLOW-POPLAR. Joui. Forestry 53:

28-32, illus.

(32) and MERZ, R. W.

1949. REHABILITATION OF LANDS STRIPPED FOR COAL IN OHIO. U.S.

Forest Serv. Cent. States Forest Expt. Sta. Tech. Paper 113,

41 pp., illus.

(33) and MERZ, R. W.

1951. OVERBURDEN ANALYSES AND STRIP-MINE CONDITIONS IN THE NORTHWESTERN DISTRICT OF THE OHIO COAL-MINING REGION. U.S.

Forest Serv. C:ent. States Forest Expt. Sta. Tech. Paper 124,

36 pp., illus.

(34) and MERZ, R. W.

1951. OVERBURDEN ANALYSES AND STRIP-MINE CONDITIONS IN SOUTHEASTERN OHIO. U.S. Forest Serv. Cent. States Forest Expt. Sta.

Tech. Paper 127, 61 pp., Ulus.

(35) LUTZ, HAROLD J., and CHANDLER, ROBERT F., JR.

1946. FOREST SOILS. 514 pp., illus. New York, London.

(36) LYON, T. LYTTLETON, and BUCKMAN, HARRY O.

1943. THE NATT'RE ,\ND PROPERTIES OF SOILS. Ed. 4, 499 pp., iHUSNew York.

(37) MERZ, ROBERT W.

1949. CHARACTER AND EXTENT OF LAND STRIPPED FOR COAL IN KENTUCKY.

Ky. Agr. Expt. Sta. Cir. 66, 27 pp., illus.
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 69

(38) MERZ, ROBERT W., and FINN, RAYMOND F.

1951. DIFFERENCES IN INFILTRATION RATES UN ORADED AND UNORADED

STRIP-MINED LANDS. U.S. Forcst ScTv. Cuiil. Stales Forest

Expt. Sta. Note 65, 2 pi).

(39) and PLASS, W. T.

1952. NATURAL FORESTATION ON A STRIP-MINED AREA IN OHIO. U.S.

Forest Serv. Cent. States Forest Expt. Sta. Note (18, 2 pp illns

(40) MiNCKLER, LEON S., and CHAPMAN, ARTHUR G.

1948. TREE PLANTINf! IN THE CENTRAL, PIEDMONT, AND SDUTHERN APPALACHIAN REiiioNS. U.S. Dept. Afir. Farmers Uni. 1994, 39 pp

ill us. '

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1952. FIELD TEST FOR ACTIVE SULFIDES IN SOIL. Soil Sci 74' 467-470

illus.

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1954. ANNUAL REPORT, 1953-1954, 271 pp., iUuS.

(44) RILEY, CHARLES V.

1953. STRIPLANDS CAN PRODUCE WILDLIFE. Ohio Conserv Bui June

pp. 2-3, 30-31, illus.

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1951. STRIP-MINED LANDS OF THE WESTERN INTERIOR COAL PROVINCE

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1949. REVEGETATION OF STRIP COAL SPOIL BANKS OF INDIANA. Illd. Coal

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1953. THE POTENTIALITIES OF REVEGBTATING AND UTILIZING AGRONOMIC

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1942. SEEDING AND PLANTING IN THE PRACTICE OF FORESTRY. Ed. 3,

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1945. THE RECLAMATION OF THE STRIP-MINED COAL LANDS OF WEST

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(52) , SMITH, RICHARD M., and GALPIN, SIDNEY L.

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(53) U.S. DEPARTMENT OF INTERIOR, BUREAU OF MINES.

1954. MINERALS YEARBOOK, 1951. 1,694 pp., illus.

(54) VISHER, STEPHEN SARGENT.

1954. CLIMATIC ATLAS OF THE UNITED ST.í.TES. 403 pp., illus. Cambridge.

(55) WILDE, S. A.

1954. REACTION OF SOILS: FACTS AND FALLACIES. Ecology 35: 89-92.

(56) WILSON, H. A., and STEWART, GWENDOLYN.

1956. THE NUMBER OF BACTERIA, FUNGI, .AND ACTINOMYCETES IN SOME

STRIP-MINE SPOIL. W. Va. Agr. Expt. Sta. Bui. 388T, 15 pp.

(57) WINTERMYER, A. M., WILLIS, E. A., and THOREEN, R. ('.

1931. PROCEDURES FOR TESTING SOILS FOR THE DETERMINATION OF THE

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12: 197-207, illus.

(58) WOOD, R. F., and THIRGOOD, J. V.

1954. SURVEY OF TREE GROWTH ON COLLIERY SPOIL HEAPS. Great Britain

Forestry Commis.sion, Report on Forest Research for the Year

Ending March, 1953. Pp. 43-47. London.
70 AGRICULTURE HANDBOOK NO. 166, U.S. DEPT. OF AGRICULTURE

APPENDIX

COMMON AND SCIENTIFIC NAMES OF TREES MENTIONED '

Common name Scientific name

Aklor, European Aluus ¡ilutinosa fL.) Gaorti;.

Ash, grt'cn Fraxinu-s jjenn.sylmutca Marsh.

Ash, white F. americana L.

Cherry, bhick Frunus .serótina Ehi'h.

Cottoiiwood, eastern Fopulun deltoides: Bartr.

Ijoeust, black Robinia pseudoacacia L.

Maple, silver . Acer sa.ccharinnm L.

Maple, sugar A. saccharum Marsh.

Oak, bur - (Juercus macrocarpa Michx.

Oak, chestnut 0- prinus L.

Oak, northern red 0- rubra L.

Osago-orange Alaclura pomifera (Raf.) Schneid.

Pine, Austrian Fiïiu-s n¡(/ra Arnold.

Fine, eastern white F. strobus L.

Pine, jack F. bankniana Lamb.

Pine, Japanese red ^ F. densiHora Sieb.

Pine, loblolly F. taeda L.

Pine, pitch F. riijida Mill.

Pine, ponderosa F. ponderosa Laws.

Pine, red /-". resinosa Ait.

Pine, Scotch F. sylrestris L.

Pine, shortleaf F. echinata yiiW.

Pine, Virginia F. rir<jiniana Mill.

Redcedar, eastern Juniperus rinjiniana L.

Spruce, white Ficea (¡lauca (Moench) Voss

Sweetgum Liquidambar styraciflua L.

Sycamore, American Flatanus occidentalis L.

Walnut, black Juijlans n i/jra L.

White-cedar, northern Thuja occidentalis L.

Yellow-poplar_ Liriodendron tulipifera L.

' Little, Ellbert L., Jr. Check li.st of native and naturalized trees of tlie United

States (including Alaska). U.S. Dept. Agr. Handb. 41, 472 pp. 1953.

2 Not listed in check list of official names.

PLANTING SITE EVALUATION RECORD

Planting site No. State

(Acres)

(•ounty Sec. Tshp.

Name and address of owner

Possible conflicts tinth other drvclopmcnts:

Will future strii)ping cover up jjart of present surface?

Any highways, roads, or lakes to be located ou area? .
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 71

Acidity (Placo a dot in the appropriate column for each pll deternuuatioii.)

Less than 4.0 4.0-4.5 4.fi-5.0 5.1-(5.0 6.1-0.9 7.0-7.5 7.6 +

Estimated percent of surface witli pH less than 4.0 _ %; 4 to 6 9 %

and 7.0 or liinher %. Acidity class: _\_\__'

(Toxic, Marfiinal, Acid, Calcareous,

(jr Alixerl)

Phi/sical characlcrinlics:

Estimated percent stone (of which % is .shale, % sandstone, % limestone, and % glacial).

Texture of soil fraction (underline one): Sandy, loamy, clayey.

Aggregation (underline): Loose, compact.

Slabilily and Topographi/: Relief (feet)

(Alax.) (Älin.)' (Áv.)

Estimated percentage of area in each relief class:

% % %

(Upper slopes and ridges) (Lower slopes and bottoms) (Graded)

Estimated gradients: % %

(Slopes) (Graded areas)

Is loose material sliding down the slopes? Is there danger of part or

entire mass slipping downward?

Is erosion slight, moderate, or severe (underline one)? Are valleys between

ridges U-shaped or V-shaped (underline one)? Is there evidence of permanent or intermittent ponds in bottoms?

Vegetation:

Ground cover classes (check one): Light Heavy

Principal species

Crown cover classes (check one): Light Moderate Heavy

Principal species

Planting recommendations: Year to plant

Species, spacing, and percent mixture:

On outside slopes

On upper slopes

On lower slopes

On graded areas

On other areas (specify)

Planting stock needed:

Species Number of

trees

Stock specification

Access roads: Are more needed to handle the planting job efficiently?

Remarks:

(Examiner) (Date)
72 AGRICULTURE HANDBOOK NO. 16 6, U.S. DEPT. OF AGRICULTURE

SULFIDE TESTS ^

Materials Needed

Geolofrist's pick (for obtaining imweathered rock samples).

Wide-nosed pliers (for crushing the samples).

12 test tubes (20 x 150 mm.).

1/4 pound of granular C.P. zinc (20-30 mesh).

Spiral of wire (a bent paper clip will do).

4-ounce bottle of fi X. hydrochloric acid (with eye-dropper).

Box of filter paper (Whatman No. 1, 5.5 cm.).

-l-ounce bottle of O.fl N. lead acetate solution (with eye-dropper).

Procedure

Crush 2-3 grams of the material to be tested and place in a test

tube. Add about 1 gram of zinc and mix. Insert the spiral of wire

part way down the tube to disperse bubbles tliat otherwise might

rise to the top of tlie tube and spoil the test by contact with the

test paper. Add 2-3 ml. (1 eye-clropperful) of hydrochloric acid.

Wait about 5 seconds for the fumes to displace the air in the test

tube and then cover the mouth of the tube with a small filter paper

freshly moistened with 2 or 3 drops of lead acetate solution. Remove tlie filter paper after 5 seconds. The color and appearance of

the deposit produced on the filter paper indicate the amount of

potentially active sulfide in the sample, as illustrated in figure 38

and described below.

Color Sulfide concentration

Slight tan coloration Very low.

Tan Low.

Brown with tan margin Moderate.

Dark brown High.

Black with silvery cast Very high.

ACIDITY TESTS

Materials and Methods

Relatively simple acidity tests can be made by using a soil testing

kit. This test, colorimetric, is applicable to soils ranging in pH

from 4.0 to 9.0. Single roll dispensers give sharp color changes for

each half pH unit from 0.0 to 14.0. A test for carbonates—indicators of calcareous reactions—can be made by simply placing a few

drops of dilute hydrochloric acid on the material to be tested:

elfervescence indicates presence of carbonates. Toxic reactions can

be detected by the use of a 10-percent solution of potassium sulfocyanate (KCNS) : if pH is below 4.0, a deep red color appears.

Sampling Procedure

The number of acidity determinations to make depends on the size

of the area and the variability encountered. First, tests on a few

spots having apparent differences in surface color and texture should

be taken to indicate the probable variability of chemical reaction.

' Procedure recommended by Deitschman and Neckers (18).

s
FORESTATION OF STRIP-MINED LAND IN THE CENTRAL STATES 73

1^ \ á)&'*y>^

U\ \lery Low/

—'^^r

«

Hait\r^i\

y~:-

:^

FicTRE 38.—Test filter papers showing the relative coloration produced by very

low to very high sulfide concentrations. The margin of the filter paper disk

can also be used to record pertinent field notes, as shown.

Very often this will suffice for areas less than 5 acres, and on larger

areas where uniform acidity conditions are evident. Where extreme

variability is encountered, samples should be taken on strips 400 to

'iOO feet apart extending across tlie original contour of the land;

on graded areas sample determinations should be made at intervals