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Agricultural Handbook No. 370

U.S. DEPARTMENT OF AGRICULTURE FOREST SERVICE
ARTIFICIAL REFORESTATION PRACTICES

FOR THE SOUTHWEST

GILBERT H. SCHUBERT,

Principal Silviculturist

L. J. HEIDMANN,

Associate Silviculturisty and

M. M. LARSON,

Forest Physiologist

Rocky Mountain Forest and Range

Experiment Station

l.t. MfiklTMIT tf «UKNTMt

Agricultural Handbook No. 370 ISSUED MAY 1970

U.S. DEPARTMENT OF AGRICULTURE FOREST SERVICE

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

Washington, D.C. 20402 • Price 35 cents.
CONTENTS

Page

Introduction 1

Seed requirements 1

Seed source 1

Seed production 2

Seed collection 2

Seed storage 3

Seedling requirements 3

Nursery stock 3

When to lift nursery stock 3

Planting stock size and quality.. 3

Stock shipment 4

Stock storage 4

Wildling stock 4

Site preparation 4

Chemical site preparation 5

Mechanical site preparation 6

Fire for site preparation 8

Planting 8

Planting methods 8

Hand planting 8

Machine planting 9

Planting procedures 10

Where to plant 10

When to plant 10

What species to plant 10

How to hand plant 10

How to machine plant 11

How many trees to plant 12

How to measure success 12

Direct seeding 12

Direct seeding methods 12

Broadcast seeding 12

Page

Spot seeding 12

Drill seeding 13

Direct seeding procedures 13

Rodent control 13

Where to use direct seeding.... 15

When to use direct seeding 15

Species for direct seeding 16

Number of seeds to sow 16

Plantation care 18

Climate and environment 18

Fire 18

Biological factors 18

Diseases 18

Insects 19

Competition 19

Small animals 19

Browsing animals 20

Summary of main points 21

Seed requirements 21

Seedling requirements 21

Site preparation 22

Planting 22

Planting methods 22

Planting procedures 22

Direct seeding 23

Seeding methods 23

Seeding procedures 23

Plantation care 23

Climate and environment 23

Fire 23

Biological factors 23

Literature cited 24

11
ARTIFICIAL REFORESTATION PRACTICES FOR THE SOUTHWEST

GILBERT H. SCHUBERT, L. J. HEIDMANN, and M. M. LARSON^

INTRODUCTION

More than a half-million acres of burned and

cutover commercial timberland in the Southwest need to be reforested. Large-scale planting and direct seeding will be required to

restore these half-million acres and many

newly burned and cutover areas to full productivity. This handbook summarizes valuable

information that can be used by foresters and

land managers in establishing new stands of

trees.

Experience has shown that natural regeneration will not satisfactorily restock these idle

acres. Many areas, especially large burns, do

not have an adequate seed source. Even in

areas with an adequate seed supply, adverse

climatic and biotic factors have prevented effective natural restocking except during a few

years in the past half century.

Many of the factors that have rendered natural regeneration ineffective also jeopardize

planting and seeding. Drought during fall,

combined with abundant competing vegetation,

is foremost. Most Southwestern ponderosa

pine seeds germinate only during the summer

wet period. If drought delays germination into

August, the seedlings cannot establish deep

roots in the remainder of growing season.

Many of the shallow-rooted seedlings are then

heaved by frost during the fall and spring.

Attrition by soil insects, tip moths, birds, rodents, and browsing animals may be severe for

as long as 15 years after initial establishment.

1 The authors are located at the Forestry Sciences

Laboratory in Flagstaff, Ariz. The Laboratory is maintained in cooperation with Northern Arizona University, Flagstaff, Ariz. Central headquarters for the Station is maintained at Fort Collins, Colo., in cooperation

with Colorado State University.

Planting, the most successful method of artificial reforestation in Arizona and New Mexico,

has several advantages over direct seeding.

Seedlings are less subject to destruction by rodents and birds than seed. The larger root systems of the seedlings, placed deeply in the soil,

are less likely to suffer damage from a fastdrying surface layer. Furthermore, planted

trees (1) can begin their season's growth 2 to

3 months earlier, (2) start with a larger root

system which continues to develop faster, to

tap more moisture, and to resist frost action

better, and (3) can better withstand partial

loss of tops and roots by insects, rodents, and

browsing animals than seedlings started from

direct seeding.

This publication includes instructions in the

following areas :

1. Methods for production of planting

stock.

2. Site preparation.

3. Planting of nursery grown seedlings.

4. Broadcast sowing on the site to be reforested.

5. Plantation care and protection from

fire, insects, disease, rodents, and browsing animals.

SEED REQUIREMENTS

SEED SOURCE

The importance of seed source was officially

recognized by the U.S. Department of Agriculture in 1939 (McCall 1939) when a seed policy

was adopted directing planters:

1. To use only seed of known locality of

origin and nursery stock grown from such seed.

2. To require from a vendor adequate evidence verifying place and year of origin for all

seedlots or nursery stock purchased.
3. To require an accurate record of the

origin of all seedlots and nursery stock used in

forest, shelterbelt, and erosion-control planting.

4. To use seeds from local, natural stands

whenever they are available.

5. When local seed is not available, to use

seed from a region v^hich has the most similar

length of growing season, mean temperature

of the growing season, frequency of summer

droughts, latitude, and other environmental

characteristics.

6. To delimit, as early as practicable, climatic zones within which seed of each species

may be safely used for forest, shelterbelt, and

erosion control.

Some exotic species or hybrids grow better

than native species; however, nonlocal seed

sources are not recommended for reforestation

projects in the Southwest until their compatibility to local environmental conditions is proven. At Fort Valley, Ariz., all ponderosa pines

(Pinus ponderosa Laws.) from California seed

sources have died. Trees from Black Hills and

Colorado seed, while as hardy as stock from

local seed, are subnormal in size and have abnormal stem form (Larson 1966).

SEED PRODUCTION

Production of seed of the major commercial

conifers has been adequate for the needs of an

expanded reforestation program in the Southwest. Good ponderosa pine cone crops occur

every 3 or 4 years, with lighter crops in intervening years. Although large trees may occasionally yield 10 pounds of seed in a single

crop, they average 2 pounds (20,000 to 24,000

seeds) in *'good'' years and 3 or 4 pounds in

**bumper" years. Heavy ponderosa pine cone

crops have been observed on the Coconino and

Kaibab National Forests in 1913, 1918, 1927,

1936, 1942, 1945, 1954, 1956, 1960, and 1965.

Good crops of the other commercial conifers

occur at about the same frequency.

Potential cone crops occasionally fail to materialize. Immature seeds may be destroyed by

cone and seed insects. In winter and spring,

Abert squirrels (Sciurus aberti Woodhouse)

cut enormous numbers of small branches bearing immature cones. Beginning in early summer, the squirrels feed on green cones until the

seeds are shed in the fall. Adverse weather

also reduces seed crops. Late-spring frosts may

kill conelets, below-average spring temperatures inhibit formation of flower buds, and excessive rain reduces pollination.

SEED COLLECTION

Seed should be collected only from trees with

good form and vigor and free of insects or

disease. Poor form and excessive limbiness as

well as susceptibility to pests may be hereditary. Seeds from isolated dominant trees

should not be used because their seeds are very

likely self pollinated. Such seeds produce a

high proportion of poor-quality progeny. Wellformed trees in plantations that originated

from seed of a desired location are good seed

sources. Plantations of unknown or questionable seed origin should be avoided.

Cone collections should not be started until

the seeds are mature. The viability of mature

seeds is usually high and the derived seedlings

are normal. In contrast, the viability of immature seeds may be low, or many of the seedlings may be abnormal and worthless (Schubert 1956).

Specific gravity of the cones is one of the

most reliable indicators of seed ripeness. Maki

(1940) found that ponderosa pine cones were

mature when they would float in SAE-30

motor oil or kerosene. The cones were sufficiently mature on a tree when three or more

cones from a freshly picked sample of five

cones floated in the test medium. Cones on all

trees within a stand do not mature at the same

time, but tests of individual trees can be discontinued when four of five trees in a stand

pass the test.

The specific gravities of mature Douglas-fir

{Pseudotsuga menziesii (Mirb) Franco), true

firs, and spruce cones have not been determined.

Cones may also be collected from squirrel

caches and from trees cut during logging.

Cone collections from squirrel caches should

not start until late fall when the seeds are

known to be mature. Cached cones that have

opened, usually the top one or two layers,

should be discarded. Germination tests have

indicated a viability of at least 80 percent for

seeds collected from cones cached near Mormon

Mountain and the San Francisco Peaks.

Cones collected during logging should be as

mature as those collected from standing trees.

Since the cones lose moisture rapidly after cutting, the flotation test must be made within a

few hours after the tree is felled.

These standard practices should be followed :

1. Care of cones after collection. Send

cones to a seed extraction site as soon as possible after collection. Allow plenty of air space

between sacks, even when they are in temporary storage.
2. Care of cones during predrying. Cones

can be predried in a heated, ventilated shed

that is rodentproof. Spread cones in a thin

layer and turn frequently to prevent molding.

Cones can be predried outside if placed in burlap bags, hung from an overhead rack, and

protected from rain. Fully mature cones require the least predrying, and their seeds are

the least damaged during processing.

3. Extraction of seed. The quickest method

to dry and open the cones is to place them in a

cone kiln. The temperature of the kiln should

not exceed 130° F. Cones will also open if they

are left in a heated shed. Turn cones frequently to obtain uniform opening of the

scales. After thß cones have opened completely, place them in a tumbler or shaker to

extract the seed. Shake or tumble cones gently

to minimize damage and to maximize recovery

of seeds.

Cones have been successfully opened by

spreading them on a large canvas or platform,

or by hanging partly filled sacks on special

drying racks in the open to air-dry. Cones

dried by these methods should be turned

periodically and protected from rain, birds, and

rodents. When weather conditions are favorable, air-drying is cheap and practical. However, if rains are frequent, drying in a heated

shed or kiln is best.

4. Labeling as to seed identity. Each sack

of cones must be tagged to show at least five

facts: (a) Species, (b) geographic location

where collected, (c) elevation of collection area,

(d) date collected, and (e) collector's name.

This information must then be transferred to

the seed lot record card and to a seed identification tag.

The card becomes part of the permanent file

and must specify: (a) the number of pounds in

the seed lot, (b) date of seed extraction, (c)

method of seed extraction, (d) number of

separate containers holding the seed, (e) storage temperature, (f) seed moisture content,

and (g) record of viability tests.

The seed identification tag must be placed on

each seed container. A copy should also be

placed inside the container as a precaution

against loss of the outside tag.

SEED STORAGE

As much as a 4-year supply of seed may be

needed to keep long-term projects going between harvests of seed crops. Seeds are actually **in storage" from the time they reach

maturity until they start to germinate. Seeds

of most conifers can be kept viable during

storage if they are mature and properly handled. Ponderosa pine seeds have been stored

successfully for at least 10 years. The two

most important factors affecting viability of

mature seeds are moisture content and storage

temperature.

To maintain high viability, seed should be :

1. Dried to a moisture content of 4 to 8 percent.

2. Placed in airtight containers.

3. Stored at 32° F. or less (preferably at

0° F.).

SEEDLING REQUIREMENTS

NURSERY STOCK

There are no forest tree nurseries in the

Southwest. Therefore, stock must be grown

elsewhere. In any case, foresters should plant

only trees that are undamaged, vigorous, properly conditioned, and from the proper seed

source.

When to Lift Nursery Stock

Studies pioneered in California have shown

that planting stock must be in good physiological condition to survive well (Stone and Schubert 1959a, 1959b). Stock lifted too early in

the fall or too late in the spring have a low

root regenerating potential and survival rate.

Stock lifted in late fall and early winter after

the trees have "hardened on" or in early spring

before active growth starts have a high root regenerating and survival potential.

Nursery climate governs the time when seedlings are ready to be lifted. Since the climate

is usually different at each nursery, the best

time to lift stock also varies. The optimum

time has not been determined for nurseries

supplying planting stock for reforestation projects in the Southwest. Until specific guides

are published, the following guidelines should

be observed :

1. Stock for fall planting should not be

lifted before it has completely hardened off.

2. Stock for spring planting should be lifted

before top growth starts.

Planting Stock Size and Quality

All planting stock should meet established

size and quality specifications before it is

shipped to the field. A good plantable tree

should: (1) Have a stem diameter of at least

0.16 inch for the pines and true firs and 0.10

inch for Douglas-fir and the spruces, (2) have

a well-developed top and root system, and (3)

be undamaged and free of disease. The time
needed to produce a tree of this size will vary

according to the nursery climate and practices.

Trees that remain after proper culling will

have a good top-root balance and be of high

quality.

Stock Shipment

Trees may be shipped by truck, rail, or air—

in refrigerated or nonrefrigerated units. The

transportation method used will depend on distances and the availability of particular types

of equipment.

For short distances, trees are usually transported by unrefrigerated trucks. For long distances, the trees should be shipped by refrigerated trucks, rail, or air.

During transit, trees must be kept moist and

cool (ideally between 34° and 40° F.). These

conditions are met when trees are shipped

under refrigeration. When shipped by unrefrigerated truck, trees should be covered and

ventilation provided. Night shipments may be

desirable in hot weather. On long truck hauls,

the trees may require more water. If stops are

made enroute, the truck should be parked in

the shade.

All tree shipments must be carefully planned.

The departure time should be scheduled to permit proper disposition of the trees immediately

upon arrival. The shipping agent or truck

driver should notify the recipient promptly

when his trees arrive. The trees must then be

examined, watered if necessary, and placed in

a cool, moist place until planted.

Stock Storage

Ideal storage conditions require a well-ventilated room, a temperature range of 34° to 36°

F., and a relative humidity above 90 percent.

Unless good storage conditions are available at

the destination, trees should be left in storage

at the nursery until needed. Even then, only a

week's supply should be shipped to the planting

site at one time.

Cold storage with controlled temperature

and humidity is preferable for extended storage after delivery from the nursery. Trees can

be stored in nursery bales or in packages for

up to 1 week in a cool shed or for up to 2 or 3

weeks in a cool, moist cellar if properly tended

to prevent heating or drying. If other facilities

are unavailable, trees may be stored during

the planting season in heel-in beds. These heelin beds should be located in shaded, moist

areas, preferably on north-facing slopes. If

artificial shade is required, it should permit

adequate ventilation.

The number of trees removed from local

storage or from heel-in beds should be limited

to 1 day's planting needs. Special precautions

must be taken to minimize disturbance of the

trees during the storage period. Each additional handling increases the possibility of

damage to the seedlings.

WILDLING STOCK

Forest-grown seedlings (Wildlings) have

been used to some extent for fill-in planting in

understocked plantations or in small-scale

planting in New Mexico.

Wildlings are usually inferior to nurserygrown trees. They generally do not have the

compact root systems needed for successful

field planting. Unless the Wildlings are readily

accessible, easy to lift without serious damage

to the root system, and are close to the planting

site, they may cost more than nursery stock.

SITE PREPARATION

Neither newly germinated nor newly planted

seedlings can compete with an established vegetative cover. With few exceptions, new seedling crops on unprepared areas die during the

two seasonal droughts (fig. 1). The late spring

drought (May-June) is more detrin^ental than

the fall drought (October-November) because

it is more severe and it occurs when seedlings

are growing most rapidly.

A dense vegetative cover depletes soil moisture, intercepts light and precipitation, and

provides a favorable habitat for insects and

animals that feed on conifer seed and seedlings

(fig. 2). Overhead shade from tall grasses and

weeds is distinctly detrimental to ponderosa

pine seedlings. Furthermore, some kinds of

vegetation may inhibit seed germination and

seedling growth.

Some plant species compete more severely

than others for limited soil moisture. For example, Arizona fescue {Festuca arizonica Vasey) and black dropseed (Sporobolits interrupt

tus Vasey) grow during the spring drought

when moisture is critical. However, mountain

muhly (Muhlenbergia montana (Nutt.)

Hitchc), blue grama (Bouteloua gracilis

(H.B.K.) Lag.), and most weeds do not begin

rapid growth until after the start of the summer rains, when moisture is more abundant.

Site preparation involves removing or reducing established vegetation, preparing a seedbed, and removing obstacles to planting, and

renders the site less favorable for destructive
^

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4.01—

3.0 —

2.0 —

JAN. FEB. MAR. APR. MAY JUNE JULY AUG. SEPT. OCT. NOV. DEC.

Figure 1.—Fifty-year average monthly precipitation at Fort Valley Experimental Forest (1909-58).

insects and rodents. The most important reason for site preparation in the Southwest is to

conserve soil moisture for establishment of tree

seedlings and early rapid growth.

The need for site preparation increases with

each year's delay in reforesting after fire or

timber cutting. Chances for successful establishment of a new stand are greatest the first

year after timber removal if the area is not

seeded to grass (fig. 3). By the second year,

the chances are much less. After 3 years or

longer, plantings on unprepared sites are usually complete failures.

CHEMICAL SITE PREPARATION

In the Southwest, a dense, herbicide-killed

grassy area is superior to a mechanically prepared area for seedling survival. However,

because patches of compact, dead grass may

interfere with planting, these areas may be

more expensive to plant.

Dalapon, an inexpensive, grass-killing chemical, was successfully used to prepare sites

for planting at Fort Valley, Ariz. (Heidmann

1967). Dalapon applied in August as low as 5

pounds active ingredient per acre completely

killed Arizona fescue and mountain muhly. Soil

remained 2 to 10 percent more moist under

2 Identification and description of commercial products in this publication are solely for information

purposes. Endorsement of any commercial product by

the U.S. Department of Agriculture is not intended and

should not be inferred.

dead grass than on denuded plots, and 10 to 15

percent higher than on untreated plots (fig. 5).

Dead grass may also serve as a mulch to reduce

frost heaving and winterkill of new conifer

seedlings. Another advantage of chemical site

preparation is that one treatment is usually

effective for several years, while mechanically

treated areas are invaded by grasses and weeds

almost immediately.

Areas should be chemically treated during

the summer preceding planting or seeding to

allow the herbicides to break down in the soil.

By then herbaceous roots are partially decomposed, and more nitrogen may be available to

the pine seedlings. Dead grasses are a poor

habitat for harmful soil insects.

Most brush species can be killed with 2,4-D

or 2,4,5-T. Although dosages and application

schedules have not been determined for most

species in the Southwest, excellent control was

obtained in California with 2 to 4 pounds of the

acid per acre applied in the spring before

growth started or in the early fall when growth

was completed (Schubert 1962). The chemicals are usually applied with a power sprayer

or from aircraft.

The cost of site preparation with chemicals

depends upon the type of sprayer and condition of the planting area. It costs $10 to $20

per acre to treat most areas. Latest recommendations for chemical treatment should be

obtained and followed.
F-516085, 516086

Figure 2.—Dense vegetative cover {A, Arizona fescue and mountain muhly at Wing Mountain and 6, native grasses and

mullein at A-1 Mountain) competes with conifer seedlings

for moisture and light and provides a favorable habitat for

destructive insects and rodents.

F-515087, 516088

Figure 3.—A 1-year-old burn (A) at time of tree planting in April

1960. The area had been seeded with a mixture of grasses

immediately after the fire in 1959. In 1961 (B) a heavy

stand of orchardgrass overtopped the young trees. The

planting failed.

MECHANICAL SITE PREPARATION

Mechanical site preparation is preferred to

chemical site preparation in brush, which must

be removed or broken up to facilitate planting.

Areas to be planted by machine require more

thorough site preparation than areas to be

planted by hand.

Complete destruction of all competing vegetation over the planting site is preferred to

preparation of small, individual planting spots

(fig. 6). Earlier literature recommended clearing spots (16 to 24 inches in diameter) or narrow, scalped strips (Pearson 1940) (fig. 7).

However, trees planted in these small spots or

in narrow strips often failed to thrive. Tree

roots quickly outgrew the cleared spots or

strips, and roots from the surrounding vegetation rapidly reinvaded the small, cleared areas.

Complete eradication of the competing vegetation provides the trees with a longer period in

which to become established and a more favorable environment for growth.
F-516089

Figure 4.—Native grasses were completely killed by dalapon

treatment at Fort Valley, Ariz, in 1961.

Brush, particularly Gambel oak {Quercus

gambelii Nutt.) and other root-sprouting species, should be uprooted with a brush rake or

similar device to remove the root system -with a

minimum loss of top soil. At times, selective

herbicides or fire have been used to deaden the

brush or grass before mechanical eradication.

Mechanically cleared areas frequently require

at least one chemical treatment to kill the new

brush sprouts or seedlings.

When bulldozers are used, loss of top soil

can be minimized by frequent and sudden

jolting of the dozer blade to shake out loose

soil from the uprooted brush. This procedure

is particularly advisable when brush piles or

windrows are to be burned. Loss of top soil

may adversely aiïect growth of the newly

planted trees.

In California, complete mechanical eradication of grass and brush on slopes of 35 percent

grade and up costs from $25 to $35 per acre

(Buck 1959). Planting sites having slopes

should be contour furrowed to reduce erosion

and retain soil moisture.

Sites should be mechanically prepared during

late summer or fall, and seedlings should be

planted the following spring. Areas that are not

planted on schedule must be reworked to destroy

any new vegetation.

APR. MAY JUNE JULY AUG. SEPT. OCT

F-516061

Figure 5.—EfFeci of ground surface condition on soil moisture in 1962.
F-516067

Figure 6.—Mechanical site preparation on an area formerly

covered by dense brush. This area is now suitable for hand

or machine planting.

F-516062

Figure 7.—Ponderosa pine seedlings being planted in narrow

scalped strips in northern Arizona.

Planting sites should never be seeded to grass

except in special multiple-use situations where

timber is not of primary importance. In these

situations, trees and grass may be planted simultaneously.

FIRE FOR SITE PREPARATION

Fire is one of the least effective tools for site

preparation. Frequently, the heat generated

by the fire stimulates germination of weed and

brush seeds stored in the duff. Furthermore,

unless the fire is extremely hot root systems

and woody stems of perennial vegetation may

not be eliminated.

Fire is more effective when combined with

chemical or mechanical treatments. After

chemical or mechanical treatment, fire is sometimes used to consume dead grass or brush.

PLANTING

Planting forest trees is the most positive

way to start a new stand when and where one

is needed. However, even planted trees die

when the job is not done right. To establish

a successful plantation: plant only healthy,

vigorous trees that are adapted to the site;

plant them on well-prepared planting areas at

the right time and in the right way; and then

provide proper care and protection. When

these requirements are fulfilled, plantations

can be successfully established even during dry

years.

PLANTING METHODS

Planting may be done by hand or machine.

In hand planting, trees are placed by hand in

holes dug with handtools or a power-driven

auger. In machine planting, trees are placed

by hand in a slit in the soil that is opened and

closed by the machine. Whether planting is

done by hand or machine depends upon the

condition of the planting area and the availability of equipment.

Hand Planting

Most planting in the Southwest has been

done with handtools. Of the two methods used

—hole planting and slit planting—hole planting has several advantages: (1) All sizes of

planting stock can be used, (2) roots can be

spread out for better contact with undisturbed

soil, (3) doubling up of the roots is less probable, (4) moist soil can be packed better

around the roots, and (5) the method can be

used in any type of soil. The slit-planting

method can be used only in light or medium

soils. In light, sandy soils, the slit method is

faster than the hole method and can be just as

successful if done right.

Power-driven hole diggers have been used

sporadically for several years in the Southwest.

Some important advantages of using hole diggers rather than conventional handtools are:

(1) Reduced hand labor, (2) more uniform

holes, (3) better planting of trees, (4) faster

planting, (5) higher survival, and (6) lower

cost per surviving tree. However, there are

8
also several serious disadvantages that must

be corrected before power-driven hole diggers

are used in preference to hand methods. The

main disadvantage is that hole diggers cannot

operate on areas with many large rocks and

roots. Other disadvantages—noxious fumes

from the gas motor, frequent breakdowns, and

operator fatigue—^have been partly eliminated

in newer models.

Two types of hole diggers are used. One is a

"casilla" hole digger operated from a powertakeoff unit (fig. 8). The other is a post-hole

digger operated from a small, portable power

source (fig. 9).

The "casilla" hole digger was field tested in

California and found satisfactory on level

ground and on gentle slopes relatively free of

rocks, roots, and other debris (Schubert and

Roy 1959). However, the production rate was

only about 480 holes per 8-hour day. Tree

survival and growth were better than in handdug holes on unprepared areas. The digger

eliminates root competition within a 30-inch

circle, and the "casilla" traps extra water. The

"casilla" digger has been used in Arizona, but

no comparative tests were made with other

methods. It is not recommended for large

planting projects.

Machine Planting

Planting machines (fig. 10) are now used in

some parts of the Southwest, and greater use

F-516068

Figure 8.—Mechanical hole digger used to prepare "casilla" approximately 30 inches in diameter with a planting hole 9

inches across by 9 inches deep.

F-516069

Figure 9.—A 4-inch soil auger driven by a flexible cable attached to a gasoline engine carried on the operator's back

can be used to dig planting holes.

F-516063, 516064

Figure 10.—Two types of planting machines being used in the

Southwest; A, the Rocky Mountain planter and B, the

Whitfiield.
is anticipated. New models can be operated on

sites that previously were impossible to plant

by machine. On fully prepared areas, machine

planting is faster, cheaper, and surer than

hand planting. Under normal situations, from

2,000-3,000 trees can be planted per machine

day on cleared areas. However, machine efficiency decreases rapidly with an increase in

rocks, stumps, logs, and other debris. Difficulties are also encountered in attempts to plant

trees that are small or extra large, and in soil

with a heavy clay content—especially when it

is wet. These areas not specifically suited to

machine planting should be hand planted.

PLANTING PROCEDURES

Proper attention to details in planting may

be of greater importance than whether planting is done by hand or by machine. Wakeley

(1954) concluded that planting too shallow and

improper closure of the planting hole accounted

for more seedling mortality than all the other

"errors*' of planting. Still, many other details,

besides the physical planting of the tree, are

important for success. Some of these details

are: (1) Where to plant, (2) when to plant,

(3) what species to plant, (4) how to plant

and (5) how many trees per acre to plant. It

is also important to know how to measure success.

Where to Plant

The land manager decides which areas will

be planted. His decisions are based on: (1)

Up-to-date planting surveys, (2) timber sitequality maps, (3) soil vegetation maps, (4)

available planting stocks, and (5) allocated

funds. He usually will schedule work on the

best quality lands first, where invested money

and manpower will produce the greatest returns.

Specifications and guidelines for placement

of trees in a planting area should be prepared

by a competent forester who has had planting

experience. The following guidelines apply

mainly to hand planting, but these procedures

should be observed also in machine planting

where applicable :

1. Select a spot where the seedling may

benefit from the shade cast by a stump, log, or

rock.

2. Select a spot with good drainage, but do

not plant on a hummock. These small mounds

often have dry centers and poor moistureholding capacities. Depressions should also be

avoided, except in areas where drainage is

good. Trees planted in deep depressions may

be buried with silt.

When to Plant

Spring is the best season to plant in the

Southwest. The spring planting season normally extends from about April 14 to May 15.

In some years planting may be started earlier,

but it should not be extended much later than

May 15.

Planting during the summer rainy season is

not recommended. Air temperatures are too

high, vegetative competition is active, and the

amount and distribution of summer rains are

too uncertain for planting. Furthermore, nursery stock during summer is in its poorest

physiological condition for planting.

Fall planting has been successful on several

occasions, but failures are common. Fall planting should not be started until the trees have

completely hardened off and the fall rains have

wet the soil to a depth of at least 1 foot. Nursery stock lifted before the trees become dormant are in poor physiological condition and

have a low potential for root production.

The unpredictable fall and winter precipitation makes fall planting more difficult to schedule and less certain to succeed. Winterkill,

most common on south slopes, is usually quite

heavy in years when the newly planted trees

are not covered by snow.

The slope aspect should be considered in

scheduling planting in either spring or fall.

South- and west-facing slopes should be

planted first in the spring. These aspects are

the first to be free of snow and the first to become too dry for planting. The reverse schedule should be followed for fall planting; eastand north-facing slopes will be the first to become inaccessible.

What Species to Plant

The general rule is to plant those species

that are native to the planting site. Introduced species may not be adapted to the new

environment. Nearly all plantings in the past

have been with ponderosa pine for wood products. Future plantings may show an increased

use of other species for a variety of purposes.

How to Hand Plant

The following procedure is generally accepted as the best way to plant by the hole

method, the preferred method of hand planting. The procedure for the slit method differs

10
somewhat, but it requires the same attention

to details.

1. Prepare spot.—Clear litter and dry soil

from a spot 12 to 15 inches square. Omission

of this step permits dust and dry debris to

fall in the hole, a common cause of failure.

2. Dig hole.—Dig the hole deep enough to

accommodate the full length of the roots.

Roots must not be doubled up in the bottom

of the hole.

3. Remove one tree from the planting bag or

tray after the hole has been dug. If more than

one seedling is removed at a time, the fine

roots may dry out before the seedlings can be

planted. The seedling must be removed carefully from the container to prevent damage to

the roots. Keep the trees in the planting bag

or tray covered and moist.

4. Set tree.—Suspend the tree so the roots

are against the rear, vertical wall of the hole.

Hold the tree so that it will be planted at about

the same depth it grew in the nursery, and

spread the roots fanwise against the rear wall.

Planting a tree too high will reduce survival

more than planting a tree an inch or so deeper

than recommended.

5. Fill the hole.—Hold the tree in position

with one hand and use the other hand to fill

half the hole with moist soil and to firm the

soil. Complete filling of the hole with moist

soil and tamp firmly in place. Hand tamping

is recommended, especially for the lower half

of the planting hole. The upper half of the

hole can be tamped with the feet or a planting

tool, but care must be taken to avoid damaging

the tree.

6. Mulch.—Push loose soil or litter around

the base of the tree to help reduce evaporation

of soil moisture. If available, three rocks (fig.

11) or pieces of bark can be placed flat around

the tree to reduce moisture loss and to restrict

competing vegetation.

How to Machine Plant

Machine planting requires the same strict

adherence to detail as hand planting (fig. 12).

Some of the more important requirements are :

1. Prepare area.—Remove all herbaceous

vegetation, litter, slash, and other debris.

Vegetation uses moisture needed for tree

growth, and interferes with the proper operation of the planting machine. Litter, slash, and

other debris also cause improper machine

operation and planting.

Figure 11.—Three rocks placed around the base ot a

planted tree provide shade and retard loss of moisture

F-516090

base of a newly

2. Check soil moisture.—Soil should be moist

but not wet. Planting machines do not operate

properly on muddy soil.

3. Observe weather.—The weather should be

reasonably calm and humid. Greater care is

required to prevent damage to trees planted

on hot, dry days.

F-516070

Figure 12.—Trees planted with a planting machine on

a well-prepared site.

11
4. Set planting depth.—Adjust coulter and

trencher to set trees with roots fully extended.

5. Pack soil—Adjust packing wheels so soil

is packed firmly around trees.

6. Protect trees.—Remove no more trees

from the container at any one time than can be

planted before the roots show evidence of drying.

7. Protect trees in carrier on planting machine.—Insure that roots are kept moist. Excessive exposure to sun and dry air will kill

the trees.

8. Regulate spacing.—Place trees in a

trench at approximate specified spacing. Avoid

setting plants on rocks, roots, or other debris,

or in a shallow trench.

How Many Trees to Plant

The present stocking goal in the Southwest

is 340 trees with an average diameter of 5

inches per acre. This rate is based on the requirement for stands with an average basal

area level of 80 square feet when the trees approach pulpwood size. Current research on

stocking levels may suggest different future

stocking goals based on site quality and desired wood product.

To achieve this stocking goal, 680 trees per

acre should be planted at approximately 8- by

8-foot spacing. This recommendation is based

on the current 50-percent mortality experienced in the Southwest. If local success deviates appreciably from the 50-percent average, an adjustment should be made to achieve

the specified stocking goal.

HOW TO MEASURE SUCCESS

An accurate estimate of the "success" of

planting must be obtained to determine effectiveness of planting methods and whether replanting is needed to develop adequate stocking.

Several methods are used to measure survival. Whatever the method, it is most important that all major site differences and all

planters are represented in the sample. To obtain such representation, run the sample lines

obliquely to both contours and planting lines.

One method is to stake, immediately after

planting, all trees within 3.3 feet of each side

of a sample line to provide a basis for future

sampling—^preferably after the first and fifth

growing seasons. Sufficient lines should be run

so that the number of staked trees is 10 to

15 times the number of acres planted. For

small plantations, sample at least 100 trees.

After the first year, natural seedlings should

be counted if they stock spots where planted

trees have died. Natural seedlings that grow

within a 4.5-foot radius (about 64 square

feet) of the stake are tallied as stocking the

spot. Both survival of planted trees and the

percentage of stocked spots can be computed

from these data.

The same procedure may be followed to

measure success for direct seeding.

DIRECT SEEDING

Direct seeding, while more economical and

flexible than planting, is less reliable. With a

large seed bank, areas can be seeded promptly

when the need arises, whereas planting requires 2 to 3 years to produce planting stock.

Total costs for seeding generally average onefourth to one-half of planting costs.

DIRECT SEEDING METHODS

There are three general direct seeding methods: (1) Broadcast seeding (either from the

air or ground), (2) Spot seeding (sowing in

prepared spots), and (3) drill seeding.

Broadcast Seeding

In broadcast seeding, seed is simply scattered on the soil. It has been the least effective

of the three methods. The main disadvantages

are:

1. Broadcast seeding requires a large

amount of seed—about 2 to 10 times more seed

than the other two methods.

2. Losses of exposed seed to birds and rodents are high.

3. Seed germination is commonly poor—^the

surface soil dries out too rapidly, even during

the summer rainy season.

4. Much of the seed falls on unfavorable

spots—rocks, stumps, logs, trash, and other

poor microsites.

Broadcast seeding has two advantages over

the other two methods—it is easier and faster.

However, some disadvantages of broadcast

seeding can be minimized by adequate site preparation, rodent control, and seed coverage.

When causes of heavy seed and seedling losses

are minimized, broadcast seeding can be a

satisfactory method of artificial regeneration.

Spot Seeding

Spot seeding has been the most effective

method in the West. It has several distinct advantages over broadcast seeding:

12
1. Less seed is required—usually less than

5,000 per acre.

2. The seed can be placed in the most favorable spots—the shady side of rocks, stumps,

and logs, and where soil is moist.

3. The seeds are covered vi^ith soil, giving

them the best chance to germinate and develop

into thrifty seedlings.

4. Seed destruction by birds is virtually

eliminated since birds feed mostly on uncovered seeds.

5. Seeds are easier to protect against rodents because spots can be covered with wire

screens. Even if spots are not screened, seed

is more likely to be missed than when it is exposed on the surface. However, since rodents

are very adept at finding seeds under the soil

surface, seed coverage alone does not provide

adequate protection.

The main disadvantage of seed-spot sowing

is the time required. The method is not much

faster than planting.

Drill Seeding

Several types of heavy-duty seed drills can be

used to sow forest tree seed. A rangeland drill

(fig. 13) was successfully tested in California

(Schubert et al. 1960) and has shown promise

in the Southwest. Improved special seeders,

which may replace the rangeland drill, have

been developed in recent years. Drilling the

seed is faster and cheaper than spot seeding,

and requires far less seed than broadcast seeding. Also, drilled seeds are not as easily found

by rodents and birds.

Drills are not satisfactory for use on steep

slopes or on areas covered with rocks or debris.

DIRECT SEEDING PROCEDURES

The requirements for successful direct seeding have been fairly well established but have

not always been achieved. Many of these requirements apply to both planting and seeding

(see sections on seed requirements, site preparation, and plantation care). Also, methods

and techniques that can be used to improve

stocking on seeded areas have been developed.

This section applies mostly to spot seeding,

but also contains information useful in broadcast and drill seeding.

Rodent Control

Without effective control, rodents—(mainly

mice Microtus and Peromyscus spp.)—^may

consume most seed. Three methods are used

to reduce losses: (1) Distributing lethal baits

over the regeneration area to reduce the rodent population, (2) covering seed spots with

screen barriers to exclude rodents from seed,

and (3) treating seed with toxic or repellent

chemicals to reduce rodent population or to

repel rodents from seed.

Lethal bait.—Rodent populations can be reduced by lethal baits, but this method has

three undesirable features: (1) Birds and

other animals may be killed if necessary precautions are not followed; (2) rodents also eat

cutworms, white grubs, and other insects that

destroy seedlings, and (3) a population

vacuum that is soon filled by rodents from adjacent untreated areas is left.

Extreme precautions must always be taken

when lethal chemicals are used in direct seeding; proper clearance must be obtained from

local authorities.^

The most commonly used rodenticides are

sodium fluoroacetate (Compound "1080") and

thallium sulfate. These lethal chemicals are

used as a soaked bait or coating on grain carriers, usually wheat, oats, or corn. Recent studies on the Lincoln National Forest, N. Mex.,

showed rodent population reductions of 97 percent with "1080" treated oats, 90 percent with

endrin, and 94 percent with DRC-714 on 10-acre

plots.

The lethal bait is placed in selected spots,

such as under logs, stumps, rocks, and other

spots where rodents travel, but where the bait

' F-516071

Figure 13.—Rangeland drill used for sowing ponderosa pine seed.

Seed is sown through the two down drills, and is covered

with the chains dragged behind.

2 Personnel of the U.S. Department of the Interior's

Fish and Wildlife Service and especially the Service's

Bureau of Sport Fisheries and Wildlife have been most

helpful in treating the seeds, and they should be consulted for the latest information.

13
cannot be reached by birds, livestock, and game

animals. The lethal bait must never be left exposed. A buffer strip 200 to 300 feet wide

around the regeneration area is heavily baited

to intercept any migrants.

Eighty to 100 bait spots per acre must be

placed in the regeneration area, and 160 to 200

must be put in the buffer strip. Each bait spot

should have about one-half ounce of treated

grain.

The time of baiting is important. Some rodents hibernate (e.g., meadow mice and chipmunks), whereas others do not (e.g., deer

mice), but all feed on any available conifer

seeds.

The following schedule is suggested for baiting to protect a late-spring or early-summer

seeding. At least two bait treatments are

needed. The first treatment should be applied

about 1 week before seeding, and the second

when the seeds start to germinate. Both the

lethal chemical and grain should be changed at

each treatment date. For example, if the first

treatment is "1080" on wheat, the second treatment should be thallium sulfate on oats.

A fall seeding will require at least three and

sometimes four bait treatments. The first

treatment should be applied about 1 week before seeding; the second in early spring when

the area becomes accessible; and the third in

late June or early July about a week before

seed germination. A fourth treatment, if

needed, should be applied in early winter to

control deer mice, which do not hibernate during the winter.

Screen barriers.—Seeds can be protected

from rodents and birds by placing small hardware cloth screens over the seed spots (fig. 14).

The seedlings also appeared to benefit from the

shade cast by the screens.

Screen barriers are quite effective, but they

do not always insure success. Their effectiveness is often reduced with repeated use in the

same area. Large squirrels and other animals

will often knock over the screens, and small

animals will tunnel under them to get the seeds.

Screen barriers are also expensive to use

and, therefore, are used mainly on small-scale

operations. The screens, which cost from 75

to 90 cents each, must be (1) transported to

the area, (2) distributed to the seeding spots,

(3) worked into the soil about 1 inch, (4) removed at the start of the second growing season, and (5) transported back to the warehouse for reuse on the next project.

Seed treatment.—The ideal method to control rodents that seriously threaten the success

of a direct-seeding project is to pretreat the

conifer seed with an effective repellent or with

a sublethal dose of a systemic poison. However,

only a few of the several thousand chemicals

tried have shown promise, and none of those

marketable are effective as repellents.

Endrin-thiram is the most widely used seed

treatment.3 Endrin, a highly toxic insecticide,

has been effective as a seed treatment for mice

but not for the larger rodents. Thiram (tetramethyl thiuram-disulfide), commonly used

as a fungicide, was added (1) to improve the

effectiveness against chipmunks and ground

squirrels, (2) to repel birds, and (3) to reduce

loss from damping-off fungi. This combination of endrin-thiram has been effective [and

has been recommended for use] in the Southeast (Derr 1964). However, since the endrinthiram concentration needed for adequate seed

protection exceeds the amount permitted under

Forest Service policy, the endrin-thiram treatment cannot be recommended for use in the

Southwest.

Although endrin is an insecticide, it does

not protect the seedlings from insects when it

is used as described above. If cutworms, grubs,

and wireworms are troublesome in the area to

be seeded, the seed spots should be treated with

chlordane.

F-410399

Figure 14.—Conical screens for protecting seed spots.

3 Recently a new compound, designated as DRC-714

by the U.S. Department of the Interior's Fish and

Wildlife Service and the Service's Bureau of Sport

Fisheries and Wildlife, at Denver, Colo., facilities, has

shown considerable promise in trials on the Lincoln

National Forest, New Mex.

14
Where to Use Direct Seeding

Direct seeding is most successful on moist

mineral soil of north slopes where vegetation

has been killed or removed to minimize competition for moisture or light, at least during

the first growing season. Freshly burned and

logged areas sometimes do not require supplemental site preparation.

Rodent populations (particularly mice) are

lowest in uncut timber stands and highest in

old cutoVer or burned areas. Therefore, newly

cut areas should be seeded the first year before

rodent populations build up, and while herbaceous competition is low or absent. Older

burns arid logged areas should be seeded only

after complete site preparation, including destruction of rodent habitat.

Spots for seeding should be selected with the

same care used in choosing a spot for planting.

The best sites provide the best opportunity for

success. Rocky areas that are difficult to plant

are often favorable for seeding. The rocks protect the seedlings from frost heaving and animal browsing.

When to Use Direct Seeding

In the Southwest both temperature and

moisture are suitable for seed germination

only after the beginning of the summer rains

in July.

During April and May, there is still adequate soil moisture for germination, but the

temperature is usually too low (fig. 15). During June, if the temperature is adequate, the

surface of the soil is usually too dry.

Pearson (1950) stated that pine seed can be

sown any time between October 1 and the following July when site conditions permit. However, seed sown in late June germinated just

as soon as that sown earlier (Larson 1961).

Therefore, sowing earlier than necessary exposes the seed unnecessarily long to birds and

rodents.

Direct-seeding projects should be planned

so they are started as late as possible and are

still completed before the end of June. This

scheduling reduces the time seed is exposed to

rodents and birds, and requires less rodent

control for effective protection. It is important

I

90

80

70

60

50

40

30

20

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JAN. FEB. MAR. APR. MAY JUNE JULY AUG. SEPT. OCT. NOV. DEC.

Figure 15.—Mean temperature data for Fort Valley Experimental Forest, 1909-42.

Highest monthly

mean maximum

Monthly mean

maximum

Monthly mean

Monthly mean

minimum

Lowest monthly

mean minimum

15
to sow before the summer rains begin so that

seeds can germinate at the earliest possible

date. Larson (1961, 1963) observed that seedlings that started earliest survived best. Also,

seedlings that germinated during the week of

July 22 grew roots nearly three times as long

by November as seedlings that germinated during the week of August 26 (fig. 16).

The usual germination period for ponderosa

pine seed is 2 to 4 weeks. If rains are late or

deficient, germination may be delayed until late

summer or fall. When this happens, most seedlings die, and resowing will be necessary.

Species for Direct Seeding

Ponderosa pine is the most important timber

species in the Southwest ; in that area the type

constitutes 75 percent of the commercial forest

area. Within this pure timber type, it is not

difficult to select the species to seed.

In the mixed-conifer types, which occupy

about 20 percent of the land (13 percent is

Douglas-fir and 7 percent is spruce-fir), a

Germination Date

July 22

22 291 5 '^ '^ ^^1 2 9 Í6 23 30| 7 14 21 28| 4 12

JULY AUG. SEPT. OCT. NOV.

DATE OF TAPROOT MEASUREMENT

Figure 16.—Average cumulative toproot penetration of seedlings

germinating at different dates (Larson 1963).

choice must be made. The choice usually will

be based on ecological suitability for the specific environments and on economic desirability.

The most logical choice would be to seed the

species that already has performed the best

on the particular site.

Large-seeded species have been most promising. Among Southwest species, southwestern

white pine (Pintes strobiformis Engelm.) has

been seeded most successfully; ponderosa pine,

Douglas-fir, and true firs with intermediate

success ; and spruce least successfully.

Number of Seeds to Sow

The amount of seed required for direct seeding depends on many variables. Some variables, such as the number of seeds per pound

and viability, can be determined with reasonable certainty. However, the effect of weather

and biotic agents on seed germination and

seedling establishment must be estimated from

past performance. At best, these are only

rough guides, since the environmental conditions vary from place to place and from year

to year.

The amount of seed required also depends

on the sowing method. Drill sowing requires

more seed than spot seeding, but considerably

less than broadcast sowing.

Spot seeding.—Sowing rates previously recommended have been too heavy. Pearson

(1950) recommended sowing 10 to 15 seeds

per spot and Krauch (1936, 1938) recommended 30 to 40 per spot.

The number of seeds sown in each spot

should be just sufficient to insure that the desired number of spots will have at least one

seedling and that few will have many seedlings.

A guide was developed in California to determine the number of seeds to sow per spot

for different stocking levels (fig. 17). To use

the guide, one must know the expected germination and survival ratios. The germination

ratio is the number of germinated seeds divided by the number sown. The survival ratio

is the number of seedlings alive after two

growing seasons divided by the number initially emerged. To obtain nearly optimum effectiveness, the survival ratio should be based

on data collected over a period of many years.

If no data are available, assume a survival

ratio of 0.40 for the first seeding, and then adjust for future sowings.

Use the following procedure to determine

the number of seeds to sow per spot (see fig.

17) :

16
PROBABILITY OF SUCCESS (PERCENT)

Figur« 17.—Stocking curves for various proixibiiitios of success

and sowing rates in spot seeding (Schubert and Powells 1964).

1. Determine the seed germination ratio

and the seedling survival ratio.

2. Multiply the germination ratio by the survival ratio to find the probability of success.

3. Locate the probability of sucess on the

horizontal axis of figure 17.

4. Extend a vertical line from the probability of success to the acceptable stocking-level

curve.

5. Run a line horizontally from the intersection on the stocking level curve to the number of seeds axis.

For example, if the germination ratio is

0.80 and the survival ratio 0.50, the probability of sucess is 40 percent. If you want 95

percent of the spots to have at least one seedling, you should sow six seeds per spot. If you

would be satisfied with stocking of 80 percent

of the spots, you should sow only three seeds

per spot.

Three items must be considered in the application of the seeding guide. First, seed germination in the field may be 10- to 30-percent

lower than in the laboratory. If the difference

is known, the germination ratio should be adjusted. Second, complete stocking requires

two or more times as much seed per spot as 80-

to 90-percent stocking. Third, a high sowing

rate results in excessive seedlings in many

spots.

The survival ratio in the Southwest is likely

to be low. Thus, many seeds are needed per

spot to obtain a high percent of stocking, and

yet many spots (those with a high survival

rate) then have far too many seedlings. To

avoid these undesirable features, it is advisable

to accept a lower proportion of successfully

stocked spots, and to sow more spots per acre

with fewer seeds per spot. Forty-percent stocking is recommended. In other words, it is better to accept 40 percent of the spots with one

or more seedlings. If more than five seeds per

spot are required, a lower stocking percentage

should be accepted.

Number of seed spots per acre.—The initial

stocking for direct seeding should be the same

as for planting, usually about 680 spots per

acre. Acceptance of a lower stocking percentage requires additional spots to produce the

680 stocked spots. To add the extra spots, reduce the distance between spots in the row,

but maintain the 8 feet between rows. For example, for 50-percent stocking, the spots

should be set 4 feet apart in the rows. If the

recommended 40-percent stocking is accepted,

the distance between spots in the rows would

be 3.2 feet (8 X 0.40 = 3.2). The following

tabulation indicates the number of spots and

spacing for different stocking percentages :

Stocking Spots per acre Distance between spot

in rows S feet apart

(Percent) (Number) (Feet)

100 680 8.0

90 756 7.2

80 850 6.4

70 971 5.6

60 1,133 4.8

50 1,360 4.0

40 1,700 3.2

30 2,267 2.4

20 3,400 1.6

10 6,800 .8

The normal range in seed requirements for

spot seeding for the Southwest is 1,700 to 3,400

per acre. This range is based on an assumption of 25- to 40-percent probability of success,

when 40 percent of the spots are stocked. A

higher acceptable stocking for the same probability of success would require more seeds.

For example, to obtain 80-percent stocking,

2,550 to 5,100 seeds per acre would be required.

Drill sowing.—For drill sowing, 10,000-

12,000 viable seeds per acre are recommended

until experience indicates that a higher or

lower rate is needed. Drill sowing requires

more seeds than spot seeding because: (1)

Many seeds will be dropped on unfavorable

17
spots, (2) a high proportion of the seeds may

be buried too deep or too shallow, and (3) some

seeds may be damaged by the metering mechanism or by the packing wheel.

The distance between rows should be established by specifications. A single-drill unit can

be operated to space rows at any prescribed

distance. Some multiple-drill units have fixed

distances between drills, whereas others permit

adjustments within limits of the machine or

obstacles on the seeding area.

The sowing rate in each row will depend on

the distance between rows and on the probability of success. For drills set 8 feet apart,

the metering mechanism should be set to drop

seeds at double the frequency needed with 4

feet between drill rows. The seeds should be

sown about one-fourth inch deep; for ponderosa pine, they should never be sown more than

a half inch deep.

Broadcast sowing.—Seeding rates will be

governed by severity of site conditions. From

16,000 to 32,000 viable seeds per acre are recommended for moist, north slopes. On the

Dudley Lake burn, Sitgreaves National Forest, about 2 pounds (approximately 22,000

seeds) of ponderosa pine were sown per acre,

but stocking was adequate only on north-facing

slopes.

Much higher rates—possibly impractical ones

—^may be required for dry, south slopes. Suggested rates for south slopes are 32,000-48,000

viable seeds per acre. Heavy seedling mortality on south slopes results from high soil surface temperature and low soil moisture, which

often cannot be corrected economically. Intermediate aspects should be seeded with about

32,000 viable seeds per acre.

The recommended rates for north slopes reflect seedling to viable seed ratios of 1:8 to

produce the required 2,000 first-year seedlings.

This goal can be achieved only where: (1) A

moist mineral seedbed has been provided, (2)

competition has been eliminated, and (3) the

seeds are protected from birds and rodents.

Seeds should never be planted on unprepared

areas.

PLANTATION CARE

Successful seeding or planting is only the

first step in reforestation. New plantations

must receive care and protection. A mortality of 30 to 40 percent may be expected during

the first decade. Mortality may be caused by

such physical factors as climate and environment, including fire, or by such biotic factors

as insects, diseases, animals, or other vegetation. Proper management can greatly reduce

the adverse effect of many of these factors.

CLIMATE AND ENVIRONMENT

Young seedlings are particularly susceptible

to heat, drought, freezing, frost heaving, and

winterkill. Shade and litter can reduce seedling losses from all these causes (Krauch 1956,

Larson 1960, Pearson 1950).

The benefits of shade or litter depend upon :

1. Amount.—Light shade improves survival

of newly planted trees of all Southwestern

species. However, any kind of dense overhead

shade is harmful. Ponderosa pine ^seedlings

require less shade than Douglas-fir, white fir

(Abies concolor (Gord. and Glend.) Lindl.), or

Engelmann spruce (Picea engelmannii Parry).

2. Type.—Dead shade furnished by rocks,

logs, or stumps is better than live shade for

initial survival of ponderosa pine and Douglasfir seedlings.

3. When.—Both shade and litter are usually

beneficial, if not too heavy, during the first

few years. After the seedlings are well-established, the need for shade is reduced. >/

4. Where.—Shade is most beneficial for

seedlings on warm, south-facing slopes, especially at the lower elevational zones of the

species. Shade is less beneficial and even harmful on cold, north-facing slopes. At higher

elevations, new seedlings of many species must

have at least partial shade.

FIRE

Fire, even so-called light fire, is lethal to

seedlings and saplings of Southwestern conifers. Grazing, if carefully timed, may effectively reduce the fire hazard due to dry grass

without excessive pine browsing. Cattle cause

most damage during the spring and fall

droughts, and little damage during the summer

rainy season. Bunchgrasses grazed to a height

of 6 inches by the end of the season will maintain an adequate vegetative cover on moderate

slopes without contributing unduly to the fire

hazard.

BIOLOGICAL FACTORS

Diseases

The most important diseases of young conifers in the Southwest are dwarf mistletoe

(Arceuthobium vaginatum f. cryptopodum

(Engelm.) Gill), root rots (Armillaria mellea

(Vahl.) Quel, and Fomes annosus (Fr.) Cke.>,

and the western gall rust (Peridermium harknessii Moore).

18
Prevention, avoidance, and direct control

methods for these and other important diseases

vary considerably depending on several factors.

For this reason, advice and assistance by qualified pathologists should be requested as necessary.

Insects

Cutvs^orms, white grubs, and tip moths are

the most serious insect pests of young trees in

the Southwest. Cutworms (Noctuidae) and

white grubs {Phyllophaga spp.) are most

abundant on areas with a heavy cover of grass

and weeds. They feed on the roots of seedlings. Tip moths (Rhyacionia spp.) often kill

terminals and deform trees—^from seedlings to

small-pole sizes. Slower growing trees usually

are more seriously injured and deformed than

fast-growing trees.

These harmful insects can be controlled.

Cutworms and white grubs can be killed with

chlordane applied to the soil at a rate of 3

pounds per acre, or their number can be greatly

reduced by complete site preparation that eliminates their main food supply. Tip moths can be

killed by chemical sprays. Pine terminals should

be sprayed before May 1 with an emulsion containing 1 quart of Dimethoate (CYGON)

emulsifiable concentrate containing 4 pounds

per gallon in 100 gallons of water. Early detection and control are important.

Competition

Young trees compete with all other vegetation and with each other to obtain those items

necessary for survival and growth. Pearson

(1942) clearly demonstrated that competing

vegetation, particularly grass, is a major deterrent to the establishment of pine seedlings.

His studies strongly emphasize the importance

of adequate site preparation.

Spring-growing grasses, such as Arizona

fescue, compete more severely than summergrowing grasses, such as mountain muhly and

blue grama. Spring-growing grasses use much

of the available soil moisture during the severe

spring drought—a critical time for survival of

young tree seedlings. The competition for light

and nutrients was considered secondary to the

competition for moisture.

Some grass species produce chemical inhibitors (Jameson 1961) that reduce seed germination and seedling growth. The importance of

these inhibitors has not been fully evaluated.

Methods to destroy competing vegetation

were discussed in the previous section on "site

preparation." Regenerated areas may be grazed

to reduce the grass competition after the trees

are tall enough to be safe from browsing. Pines

taller than 3 feet are seldom browsed by cattle.

Small Animals

Many species of small animals seriously damage young forest trees. Mice, squirrels, rats

(Neotoma and Dipodomys spp.), and chipmunks destroy small seedlings. Pocket gophers

(Thomomys spp.) feed on their roots. Rabbits

(Lepus and Sylvilagus spp.) and porcupines

(Erethizon spp.) girdle and cut stems of larger seedlings (fig. 18). In fact, entire plantations have been destroyed or deformed by these

animals !

Control methods differ. Complete removal

of the vegetation before planting helps to reduce the number of small animals by lessening

their food supplies and cover. These animals

also may be killed by poison. Repellents, such

as TMTD and ZAC,* have been effective against

rabbits. Porcupine damage is most frequent

* TMTD = tetramethyl thiuram disulfide (arasan) ;

ZAC = zinc dimethyl dithio carbamate cyclohexylamine complex.

F-516074

Figure 18.—Young ponderosa pine recovering from severe

injury caused by porcupine.

19
along streams, around meadows, and in areas

adjacent to rock outcrops suitable for dens.

Trapping, shooting, and poisoning have been

used to reduce porcupine populations.

Browsing Animals

Cattle (fig. 19), sheep, and elk (Cervus spp.)

(fig. 20) have severely damaged and killed

young conifer reproduction in many localities

throughout the Southwest. On the Coconino

National Forest, Ariz., domestic livestock frequently have browsed or trampled up to 90

percent of the small trees in new plantations.

In a recent study, covering a 3-year period on

Figure 19.—Cattle damage to ponderosa pine seedling. Most

of the surviving trees in this plantation were browsed and

in poor condition a few months after planting.

F-516091

Figure 20.—Ponderosa pine seedlings badly "hedged"

by repeated browsing by deer.

three 40-acre plots from which domestic livestock was excluded, all ponderosa pine seedlings more than 3 years old and less than 4 feet

tall were browsed by deer.

Livestock damage on coniferous reproduction varies by (1) kind of animals, (2) season

of grazing, (3) intensity of grazing, and (4)

size of the trees. Sheep are by far more destructive than cattle or horses. Even under

light to moderate sheep grazing, conifer seedlings have suffered heavy damage. Pearson

(1950) reported that sizable areas of the 1919

reproduction suffered a loss of 50 to 75 percent

of the seedlings under 3 years old. After 5 or

6 years, very litle damage was caused by cattle.

In general, cattle seldom browse trees taller

than 3 feet, whereas sheep may seriously damage trees up to 5 feet tall.

Cassidy (1937a, 1937b) found browsing by

cattle and sheep were related primarily to conditions causing thirst. Damage was most

severe during the May-June drought, but it

also occurred during short, rainless periods in

the summer and drought during the fall. Livestock browsing during the May-June drought

was confined mainly to the terminal leaders;

during the fall drought, needles were eaten,

primarily by sheep (Parker 1948). Damage by

cattle and sheep could be appreciably reduced

by providing an adequate, accessible supply of

water, and by stocking only on the basis of the

volume of green feed.

Plantations should not be grazed for the first

5 or 6 years. Even after this initial period,

cattle grazing should be deferred until about

July 15, until seedling terminals are out of

reach. If grazing is deferred regularly until

mid-July, cattle could be used effectively in

older plantations to: (1) Utilize the bunchgrasses without seriously damaging the pines,

(2) encourage pine regeneration by relieving

grass competition, and (3) lower the fire hazard by reducing the volume of dry grass carried over into the succeeding fire season.

For sheep, Pearson (1950) suggested enforcement of a 1-night bedding rule, with bed

grounds at least one-half mile apart. Grazing

need not be deferred after seedlings have

grown 3 to 5 feet tall, which may be 10 to 15

years after planting.

Deer begin to browse pine shoots earlier than

domestic livestock. Heidmann (1963) found

that shoot damage can be greatly reduced by

treatments with either of two chemical deer

repellents, TMTD or ZAC (fig. 21). Only 8 or

9 percent of repellent-treated shoots were

20
F-516092, 516093

Figure 21.—Heavily browsed ponderosa pine seedlings {A)

treated with ZAC in 1958. Five years later (B) most terminals

are out of reach.

browsed, compared with 56 percent of untreated shoots (fig. 22). Since browsing occurred only during active terminal growth in

June and July, the repellent should be applied

in May before growth starts, until the trees

are out of the reach of deer. Planted or natural seedlings, 3 to 4 feet tall may be released

from deer browsing with one repellent treatment. Nursery stock may be treated before

lifting for about $0.80 per M.

SUMMARY OF MAIN POINTS

More than one-half million acres are in need

of reforestation in the Southwest. Both experience and research have demonstrated that

60

50

40 I

Ci

20

1

Check

/

(

ZAC ^

^•> TMTD

rr-r- ...-.-.

JUNE JULY AUG. SEPT. OCT. NOV.

Figure 22.—Cumulative percentage of ponderosa pine twigs

browsed by deer during the first year after treatment at

Fort Valley, 1958.

successful plantations are possible if the job is

done right (ñg. 23). This manual summarizes

the important points that should guide the

land manager in establishing new stands of

trees.

SEED REQUIREMENTS

Seed Source.—Use local seed when possible.

If none is available, use seed from a source with

a similar climate.

Seed Production.—Good seed years occur

about once in 3 or 4 years, and a bumper crop

occurs about once in 7 to 10 years. Potential

seed crops may fail to materialize due to the

activity of insects or squirrels, or to adverse

weather.

Seed Collection.—Maintain at least a 4-year

seed supply. Collect only mature seed from

trees with good form and vigor. Plantations

from a known seed source may be good collection areas.

Seed Storage.—Seed should be dried to a

moisture content of 4 to 8 percent, put into airtight containers, and stored at O"' F.

SEEDLING REQUIREMENTS

Lifting Nursery Stock.—Do not lift trees in

the fall until they are hardened off. Spring

21
F-516066

Figure 23.—Successful ponderosa pine plantation established in

1917 at Fort Valley Experimental Forest.

lifting must be completed before top growth

starts.

Size and Quality.—A plantable tree should

have a stem diameter of at least 0.16 inch for

the pines and true firs and 0.10 inch for other

species. It must be undamaged, have a welldeveloped top-root system, and be free of

disease.

Stock Shipment.—Trees must be kept cool

and moist, and must be shipped by the fastest

available means.

Stock Storage.—Trees should be stored in a

moist, cold room (34° to 36° F.) either at the

nursery or the forest headquarters, or in heelin beds at the planting site.

Wildling Stock.—Extreme care must be taken

to minimize damage to roots and to keep them

moist. Nursery-grown stock is preferred.

SITE PREPARATION

General.—For best results from seeding or

planting, all competing vegetation must be removed. Dense vegetation depletes soil moisture, intercepts light, and provides a favorable

habitat for some seed- and seedling-eating rodents and insects.

Chemical Site Preparation.—Brush can be

controlled with 2,4-D or 2,4,5-T, and grass can

be controlled with dalapon. Dead grass helps

conserve soil moisture. Follow recommended

dosages and timing to obtain the best kill. Be

sure to follow all precautions given on the container label.

Mechanical Site Preparation.—Complete removal of vegetation over large areas is preferred to small patch scalping. Sites should be

prepared in late summer or fall prior to planting.

Fire for Site Preparation.—It is not effective

when used alone, but it can be useful in combination with other methods.

PLANTING

Planting Methods

Hand Planting.—Most trees are now planted

in holes dug with handtools. Several types of

power augers are available for hole digging.

Use of these augers may speed the planting,

reduce the hand labor required, and improve

survival.

Machine Planting.—On suitable areas, machine planting is the easiest, quickest, and most

economical method of planting. The machines

operate best on level or gentle slopes where the

soil contains few large rocks, roots, stumps,

and other debris. Steeper slopes can also be

planted by machine if contour trenches are dug

before or during planting.

Planting Procedures

Where to Plant.—The most favorable areas

should be planted first. Select individual planting spots that offer the best chance for success: spots where there is no competing vegetation and where the soil is deep and well

drained. Also, take advantage of dead shade

from stumps, logs, and rocks, but do not plant

in vegetated places or in places closer to living

trees than one-half the height of the trees.

When to Plant.—Spring planting is better

than fall planting. Spring planting should begin as soon as the site is open and should end

about May 15. Fall planting should be delayed

until the ground is thoroughly moistened to a

depth of 1 foot and the trees have hardened

oflf. Plant south slopes first in the spring, and

north slopes first in the fall.

Species to Plant.—Plant only species known

to be adaptable to the site and climate.

How to Hand Plant.—Careful attention

must be given to the following steps: (1) Preparing the spot, (2) digging the hole, (3)

handling the seedling to prevent root dam22
age, (4) keeping the tree roots moist, (5) placing the tree in the hole, (6) filling the hole,

and (7) mulching the planting spot.

How to Machine Plant.—Strict adherence

must be given to the following steps: (1) Preparing the area, (2) checking the soil moisture, (3) planting when weather is reasonably

calm and moist, (4) setting the tree at correct

depth, (5) packing soil around the roots, (6)

keeping the roots moist, and (7) placing the

trees in the trench.

How Many Trees to Plant,—It is recommended that 680 trees per acre be planted on

an 8- by 8-foot spacing. This number is required to achieve present stocking goals of 340

trees per acre with an average diameter of 5

inches.

How to Measure Success.—Run simple lines

obliquely to both contour and planting lines.

Stake all trees within 3.3 feet of the sample

line. Make survival counts at least at the end

of the first and fifth growing seasons. Compute the percentage of survival and that of

stocked spots. The same procedures may be

followed to measure success for direct seeding.

DIRECT SEEDING

Seeding Methods

Broadcast Seeding.—Although fast and

flexible, broadcast seeding has been the least

effective method and has required the most

seed. However, if it is done on properly prepared sites, it may be the best way to seed large

areas to keep timberland productive.

Spot Seeding.—This has been the most effective method. It requires the least seed and

the seed can be placed in the best locations and

covered with soil to improve chances of germination and early survival.

Drill Seeding.—This method has not been

tried in the Southwest, but it has many of the

advantages of seed-spot sowing, requires less

seed than broadcast seeding, and is faster than

spot seeding.

Seeding Procedures

Rodent Control.—Rodents must be controlled

to make any method of direct seeding feasible.

The use of wire screens has been the only consistent way of protecting the seed on experimental plots, but the method is expensive. An

endrin-thiram repellent is widely used, but it

is not always successful. Poisoning has been

effective in many places.

Where to Direct Seed.—Fresh timber burns

and logged areas are most promising for direct

seeding. Frequently these areas can be seeded

without additional site preparation.

When to seed.—The best time to seed is during the last half of June. This is shortly before the summer rains needed for seed germination, and thereby lessens the time seeds are

exposed to damage by rodents and birds.

Species to Direct Seed.—The best species to

sow are ponderosa pine, limber pine, and Douglas-fir. The species should be adapted to the

area.

Number of Seeds to Sow.—Seeding rates will

vary considerably, depending on sowing

method, seed quality, and specific site. Peracre rates with good seed range from 1,700 to

4,800 for spot seeding; from 10,000 to 12,000

for drill seeding; and from 16,000 to 48,000 for

broadcast seeding on moist, well-prepared

areas.

PLANTATION CARE

Climate and Environment

Young seedlings are particularly susceptible

to excessive heat, drought, and cold. Light to

moderate dead shade has a beneficial effect on

seedlings and transplants during their period

of establishment. After trees are well established, shade is no longer required and may

even be harmful.

Fire

Provide an adequate firebreak, and reduce

the amount of heavy fuels on the regeneration

area. After trees are free from browsing danger, grazing may be used to reduce the amount

of grass fuel.

Biological Factors

Insects.—Cutworms, white grubs, and tip

moths are the most damaging insects to seedlings and young trees. Cutworms and white

grubs can be controlled through complete site

preparation and insecticide treatments. Damage by tip moths can be reduced by use of insecticides and by maintaining vigorous trees.

Diseases.—The most common diseases of

young plantations are dwarf mistletoe, two

sDecies of root rot, and western gall rust. All

dwarf mistletoe- and rust-infected trees should

be eliminated in and adjacent to the regeneration area before planting. Areas with root rot

should be avoided.

Competition.—Competing grasses can be

killed with dalapon without damage to ponderosa pine. Herbicides have been used in

other areas of the Nation to release conifers

23
from brush, but they have not been tested in

the Southwest. Generally, 2,4,5-T has been the

best to use.

Small animals,—Rabbits, gophers, and other

small rodents may destroy small trees by girdling the stem or by cutting the roots. Populations are controlled by poisoning or by removing their protective cover and food supply.

Porcupines girdle trees from seedlings to those

of pole size. Shooting and poisoning are the

most common methods of control.

Browsing animals.—^Livestock should be restricted from regeneration areas, especially

during droughts. However, grazing can be

used to reduce both the fire hazard and the

competition from herbaceous species. Deer

browsing can be reduced by spraying trees

with repellents.

LITERATURE CITED

BoYCE, JOHN SHAW.

1948. Forest pathology. Ed. 2., 550 pp.,

illus. New York: McGraw-Hill Book

Co., Inc.

BUCK, J. M.

1959. Site preparation for forest regeneration in California,* USDA Forest

Serv., Calif. Region, 26 pp., illus.

CASSIDY, H. 0.

1937a. How cattle may use cut-over ponderosa pine-bunchgrass ranges with

minimum injury to reproduction.*

USDA Forest Serv., Southwestern Forest and Range Exp. Sta. Res. Note 15,

3 pp. (Rocky Mountain Forest and

Range Expt. Sta., Ft. Collins, Colo.)

1937b. How to handle sheep on cut-over

ponderosa pine-bunchgrass ranges to

keep injury to reproduction to a minimum.* USDA Forest Serv., Southwestern Forest and Range Expt. Sta. Res.

Note 16, 2 pp. (Rocky Mountain Forest

and Range Expt. Sta., Ft. Collins, Colo.)

DERR, HAROLD J.

1964. New repellent formulation for direct seeding. J. Forest. 62: 265, illus.

HEIDMANN, L. J.

1963. Deer repellents are effective on ponderosa pine in the Southwest. J. Forest.

61: 53-54, illus.

1967. Herbicides for preparing ponderosa

pine planting sites in the Southwest.*

Rocky Mountain Forest and Range Exp.

Sta., U.S. Forest Serv. Res. Note 83, 4

pp., illus.. Ft. Collins, Colo.

JAMESON, DONALD A.

1961. Growth inhibitors of native plants

of northern Arizona.* USDA Forest

Serv. Rocky Mountain Forest and

Range Exp. Sta. Res. Note 61, 2 pp.. Ft.

Collins, Colo.

KRAUCH, HERMAN.

1936. Some factors influencing Douglasfir reproduction in the Southwest. J.

Forest. 34: 601-608.

1938. Use of protective screens in seedspot sowing found to serve two-fold purposes. J. Forest. 36: 1240.

Address requests for copies to the originating office.

1956. Management of Douglas-fir timberland in the Southwest.* USDA Forest

Serv., Rocky Mountain Forest and

Range Exp. Sta., Sta. Pap. 21, 39 pp.,

illus.. Ft. Collins, Colo.

LARSON, M. M.

1960. Frost heaving influences droughthardiness of ponderosa pine seedlings.

USDA Forest Serv., Rocky Mountain

Forest and Range Exp. Sta. Res. Note

45, 2 pp.. Ft. Collins, Colo.

1961. Seed size, germination dates, and

survival relationships of ponderosa pine

in the Southwest.* USDA Forest Serv.,

Rocky Mountain Forest and Range

Expt. Sta. Res. Note 66, 4 pp., illus., Ft.

Collins, Colo.

24
1963. Initial root development of ponderosa pine seedlings as related to germination date and size of seed. Forest Sei.

9: 456-460, illus.

1966. Racial variation in ponderosa pine

at Fort Valley, Arizona.* U.S. Forest

Serv., Rocky Mountain Forest and Range

Exp. Sta. Res. Note 73, 7 pp., illus..

Ft. Collins, Colo.

MAKI, T. E.

1940. Significance and applicability of

seed maturity indices for ponderosa

pine. J. Forest. 38: 55-60.

MCCALL, M. A.

1939. Forest tree seed policy of the U.S.

Department of Agriculture. J. Forest.

37: 820-821.

PEARSON, G. A.

1934. Grass, pine seedlings and grazing.

J. Forest. 32: 545-555, illus.

1940. Reforestation in the Southwest by

CCC camps. CCC Forest. Publ. 7, 14

pp., illus.

1942. Herbaceous vegetation a factor in

regeneration of ponderosa pine. Ecol.

Monogr. 12: 315-338, illus.

1950. Management of ponderosa pine in

the Southwest. U.S. Dep. Agr., Agr.

Monogr. 6, 218 pp., illus.

SCHUBERT, GILBERT H.

1955. Effect of storage temperature on

viability of sugar, Jeffrey, and ponderosa pine.* USDA Forest Serv., Calif.

Forest and Range Expt. Sta. Res. Note

100, 3 pp.

1956. Effect of ripeness on the viability

of sugar, Jeffrey, and ponderosa pine

seed. Proc. Soc. Amer. Forest. 1955:

67-69.

1962. Chemicals for brush control in California reforestation.* USDA Forest

Serv., Pac. Southwest Forest and Range

Expt. Sta. Misc. Pap. 73, 14 pp., Berkeley, Calif.

—, BUCK, JOHN M., and EVANKO,

ANTHONY B.

1960. Rangeland drill used in reforestation in California.* USDA Forest Serv.,

Pac. Southwest Forest and Range Expt.

Sta. Misc. Pap. 42, 4 pp., illus., Berkeley,

Calif.

and FOWELLS, HARRY A.

1964. Sowing rates for reforestation by

the seed-spotting method.* USDA Forest Serv., Pacific Southwest Forest and

Range Exp. Sta. Res. Note 44, 9 pp.,

illus., Berkeley, Calif.

SCHUBERT, GILBERT H., and ROY, DOUGLASS F.

1959. Tests of sandwich planting and the

mechanical planting-hole digger in California.* USDA Forest Serv., Pacific

Southwest Forest and Range Expt. Sta.

Res. Note 151,10 pp., illus.

STONE, EDWARD C, and SCHUBERT, GILBERT H.

1959a. Root regeneration by ponderosa

pine seedlings lifted at different times

of the year. Forest Sei. 5: 322-332,

illus.

and SCHUBERT, GILBERT H.

1959b. The physiological condition of ponderosa pine (Pinus ponderosa Laws.)

planting stock as it affects survival

after cold storage. J. Forest. 57: 837-

841, illus.

WAKELEY, PHILIP C.

1954. Planting the southern pines. U.S.

Dep. Agr., Agr. Monogr. 18, 233 pp.,

illus.

i^ U.S. GOVERNMENT PRINTING OFFICE: 1970 D 356—483

25
DISCLAIMER

Identification and description of commercial products in this publication are solely for

information purposes. Endorsement of any

commercial product by the U.S. Department

of Agriculture is not intended and should not

be inferred.

PRECAUTIONS

Pesticides used improperly can be injurious to man, animals, and plants. Follow the

directions and heed all precautions on the

labels.

Store pesticides in original containers under lock and key—out of the reach of children and animals—and away from food and

feed.

Apply pesticides so that they do not endanger humans, livestock, crops, beneficial

insects, fish, and wildlife. Do not apply pesticides when these is danger of drift, when

honey bees or other pollinating insects are

visiting plants, or in ways that may contaminate water or leave illegal residues.

Avoid prolonged inhalation of pesticide

sprays or dusts; wear protective clothing

and equipment if specified on the container.

If your hands become contaminated with a

pesticide, do not eat or drink until you have

washed. In case a pesticide is swallowed or

gets in the eyes, follow the first aid treatment given on the label, and get prompt

medical attention. If a pesticide is spilled

on your skin or clothing, remove clothing

immediately and wash skin thoroughly.

Do not clean spray equipment or dump excess spray material near ponds, streams, or

wells. Because it is diflicult to remove all

ttaces of herbicides from equipment, do not

use the same equipment for insecticides or

fungicides that you use for herbicides.

Dispose of empty pesticide containers

promptly. Have them buried at a sanitary

land-fill dump, or crush and bury them in a

level, isolated place.

NOTE : Some States have restrictions on the

use of certain pesticides. Check your State

and local regulations. Also, because registrations of pesticides are under constant

review by the U.S. Department of Agriculture, consult your county agricultural agent

or State Extension specialist to be sure the

intended use is still registered.

Endrin is being examined and reevaluated ;

do not use endrin unless it is cleared for a

specific project.