PACIFIC NORTHWEST FOREST AND RANGE EXPERIMENT STATION

U. S. DEPARTMENT OF AGRICULTURE FOREST SERVICE

About This File: 

This file was created by scanning the printed publication. Misscans identified

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Abstract

This report supplements a slide-tape presentation of 

the same title. Part I of the report describes the current practice of nitrogen fertilization of Douglas-fir

forests in western Washington and Oregon and the effects

of this fertilization on tree growth and water quality.

Part II discusses factors that affect costs and revenues

from investments in forest fertilization. The appended

tables, figures, and work sheet enable the user to prepare a break-even economic analysis for fertilization

projects. This information should be useful in selecting

stands for fertilization and in preparing Environmental

Assessment Reports.

Metric Equivalents

1 acre = 0.40469 hectare 

1 cubic foot = 0.0283 cubic meter

1 pound = 0.4536 kilogram
Contents

Page 

PART I. BIOLOGICAL BASES AND EFFECTS OF NITROGEN 

FERTILIZATION . . . . . . . . . . . . . . . . . . . . . 1

YIELDS FROM DOUGLAS-FIR FORESTS . . . . . . . . . . . . . . . . 1

Unmanaged Forests . . . . . . . . . . . . . . . . . . . . . 1

Managed Forests . . . . . . . . . . . . . . . . . . . . . . 2

FERTILIZATION TO INCREASE YIELD . . . . . . . . . . . . . . . . 3

The Current Practice. . . . . . . . . . . . . . . . . . . . 3

What We Know . . . . . . . . . . . . . . . . . . . . . . . 3

Is Fertilization a Suitable Tool? . . . . . . . . . . . . . 5

HOW RELIABLE IS FOREST FERTILIZATION? . . . . . . . . . . . . . 5

Probability of Response . . . . . . . . . . . . . . . . . . 5

Effects of Nitrogen Fertilizer on 

Douglas-fir Growth . . . . . . . . . . . . . . . . . . . . 6

Improving Reliability . . . . . . . . . . . . . . . . . . . 6

HOW ENVIRONMENTALLY SAFE? . . . . . . . . . . . . . . . . . . . 7

Results From Stream Monitoring . . . . . . . . . . . . . . . 7

Avoiding a Potential Problem . . . . . . . . . . . . . . . . 9

Energy Trade-Offs . . . . . . . . . . . . . . . . . . . . . 9

SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

PART II. HOW ECONOMIC? . . . . . . . . . . . . . . . . . . . . . 10

TREATMENT COSTS . . . . . . . . . . . . . . . . . . . . . . . 10

Initial Costs . . . . . . . . . . . . . . . . . . . . . . 10

Interest Charges . . . . . . . . . . . . . . . . . . . . . 12

REVENUE . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Volume Gained . . . . . . . . . . . . . . . . . . . . . . 13

Stumpage Price . . . . . . . . . . . . . . . . . . . . . . 14

REVENUE REQUIRED TO BREAK EVEN . . . . . . . . . . . . . . . . 17

What Break-Even Volume? . . . . . . . . . . . . . . . . . . 17

What Break-Even Price? . . . . . . . . . . . . . . . . . . 19

OTHER FINANCIAL CONSIDERATIONS . . . . . . . . . . . . . . . . 21

Effect of Income Taxes . . . . . . . . . . . . . . . . . . 21

Cash Flow Management . . . . . . . . . . . . . . . . . . . 21

Cash Flow Effects. . . . . . . . . . . . . . . . . . . . . 21

SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

LITERATURE CITED . . . . . . . . . . . . . . . . . . . . . . . . 22

APPENDIX A . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

APPENDIX B . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

APPENDIX C . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Preface

Fertilizing Douglas-fir Forests1/

This report is in two parts. In Part I, we will discuss some

of the biological bases of forest fertilization and describe the

current practice of operational fertilization. We will then discuss both the reliability of fertilization for increasing tree

growth and its environmental impacts. In Part II, we will show

how to evaluate the economics of forest fertilization.

After reading and referring to this report, you should be able

to:

1. Describe the current practice of fertilizing Douglas-fir

forests, i.e, fertilizer prescription and stand selection.

2. Describe the effect of N fertilizer on Douglas-fir growth.

3. Cite evidence about some environmental impacts of N fertilization and use this information to prepare Environmental Assessment Reports.

4. Enumerate and discuss factors that affect the costs and

revenues from investments in forest fertilization.

5. Use the accompanying worksheet to prepare a break-even

analysis for your fertilization projects.

1/ This General Technical Report supplements a slide-tape presentation titled,

Fertilizing Douglas-fir Forests. This slide tape (772.1-.2 S-T) is available for

rent or purchase from The Forestry Media Center, School of Forestry, Oregon State

University, Corvallis, Oregon 97331.
PART I. Biological Bases and Effects of 

Nitrogen Fertilization

Yields From Douglas-fir Forests 

UNMANAGED FORESTS

Douglas-fir is the predominant

tree species in nearly one-half of

the commercial forests in western

Washington and Oregon. Yield from

natural, unmanaged stands varies

greatly and largely depends on the

number of trees occupying a site 

and the inherent productivity or

quality of the site. For example,

harvesting of all live trees from 

a normal site quality V stand at 

60 years would provide about 3,500

cubic feet per acre (McArdle et al.

1961) or enough wood to build one

typical three-bedroom house (fig. 1).

In contrast, harvesting all live

trees from a normal 60-year-old,

site I stand would yield about

12,500 cubic feet per acre or enough

wood to build nearly four typical

houses:

The two solid lines in figure 1

represent trends in gross yield.

Gross yield is the volume of live

trees plus mortality, i.e., the

cumulative volume of trees normally

lost through competition, insects,

and disease. This mortality volume

averages about 20 percent of the

total or gross growth of unmanaged,

well-stocked stands of Douglas-fir.

Reducing or salvaging this mortality

volume can increase usable yields

from our forests.
2

MANAGED FORESTS

Most volume normally lost in

unmanaged forests can be recovered

in managed forests. By precommercially thinning young stands, foresters eliminate excess trees that

will not reach merchantable size 

and thereby concentrate growth onto

future crop trees. By commercially

thinning older stands, dead trees 

of merchantable size are salvaged 

as part of the thinning operation.

In addition to controlling numbers and sizes of trees which share

the site, foresters can increase site

productivity by improving environmental conditions. Some environmental factors can be manipulated 

with relative ease, but others like

temperature and precipitation are

difficult to change. Moreover,

correcting the initial growth-limiting

factor will increase growth until 

some other factor becomes limiting.

This principle is illustrated by the

barrel analogy (fig. 2).
3

Consider this barrel a forest

site we want to improve. Each

stave of the barrel represents a

productivity factor. The level of

production obtainable at this site

is limited by the factor with the

lowest opening in the barrel. In

this example, the amount of available nitrogen is the first growthlimiting factor. If we remedy this

by applying nitrogen fertilizer,

we plug this weakness and increase

production to the next factor in

short supply. This next factor

may be a physical property of the

soil like compaction or stoniness.

We can readily improve compaction

in the surface soil by mechanical

means, but correcting stoniness is

usually too costly. Therefore, on

this theoretical site--as in a

practical field situation--we would

add nitrogen until production was

limited by some factor beyond our

control.

Fertilization to lncrease Yield

THE CURRENT PRACTlCE

Forest fertilization is developing into a practical means for increasing yields of Douglas-fir

forests of western Washington and

Oregon. This commercial practice

was preceded by numerous field

trials where fertilizer was spread

uniformly over the soil and trees

were carefully measured for growth

in diameter and height. These

trials have provided direct evidence

that nitrogen fertilizers can increase growth of established stands;

direct evidence led to large-scale

applications.

The first operational fertilization was in 1965 when 1,500 acres

of Douglas-fir on Crown Zellerbach’s

holdings near Molalla, Oregon were

treated with urea prills, small,

white spheres of nitrogen fertilizer.

For the l0-year period of 1965

through 1974, nitrogen fertilizer

was applied to at least 825,000

acres in western Washington and 

Oregon.2/ About 90 percent of this 

2/Personal communication with Robert

T. Bergland, former Fertilization Forester,

Washington State Department of Natural

Resources, Olympia, Washington, on

October 22, 1975.

acreage was industry-owned forests.

Helicopters were used almost exclusively to fertilize these forests.

Generally, the prescribed treatment

was 150 or 200 pounds of elemental

nitrogen per acre, applied as urea

prill or larger forestry-grade granules.

WHAT WE KNOW

Although fertilization has joined

traditional management tools like

planting and thinning to increase

wood production, researchers and

land managers are continuing to

improve gains from fertilization.

We currently have general answers

to questions concerning which

nutrient elements, dosages, and

fertilizers should be used, and when

and how they should be applied. Refining these general answers will

increase the gains from current

practices.

Which nutrients?--Current applications of nitrogen are based on

past observations that nitrogen

fertilizers frequently increase

growth of Douglas-fir at a wide

range of locations. Other elements

such as phosphorous, potassium, and

sulphur have also been tested in combination with nitrogen; but these

elements seldom improve the gain

achieved from applying nitrogen alone

in the Pacific Northwest (Gessel 

et al. 1965, Crossin et al. 1966,

Steinbrenner 1968, Heilman 1971,

Miller and Reukema 1974).

Douglas-fir, like other plants,

requires relatively large quantities

of nitrogen compared to most other

elements. For example, productive

stands annually require 40 to 100

pounds of nitrogen per acre. Most

of this annual requirement is met

by the roots which extract inorganic

nitrogen from the soil and forest

floor; however, some of this requirement is provided by internally recycling N extracted in previous

years. Although soils of commercial

Douglas-fir forests contain 2,000

to more than 20,000 pounds of nitrogen per acre (Gessel et al. 1972),

most of this nitrogen is trapped 

in living organic matter or organic

residues. Each year, only a small
4

Which source of N?--Most nitrogen

fertilizer currently applied to

Douglas-fir forests is urea. Urea 

is used primarily because of Its relatively low initial cost per pound 

of nitrogen and because its higher

concentration of nitrogen (46 percent)

provides a greater net payload than

other nitrogen fertilizers like 

ammonium nitrate (34 percent) (table 1).

fraction is mineralized into inorganic

nitrogen and made available:to trees,

other plants, and micro-organisms, 

all of which compete for this limited

nutrient. Rates of N turnover in

many stands are frequently inadequate

to,meet tree requirements, as shown 

by the response that usually follows

fertilization with 150 or more pounds

of nitrogen per acre.

How much?--The biologically and

economicaLLy optimum fertilizer dosage

for established.stands of Douglas-fir

probably lies between 150 and 300

pounds of nitrogen per acre. Lesser

amounts may fail to provide measurable effectS. Larger amounts may 

provide slightly more volume and

longer duration of response (fig. 3),

but in some locations can lead to

increased mortality (Lee 1974) or

snow;or winter breakage brought on 

by sudden stimulation of foliar 

growth (Miller and Pienaar 1973).
5

Application of urea during periods

of dry, warm weather should be

avoided because such climatic conditions could lead to gaseous losses

of nitrogen and reductions in the

amount available for growth (Watkins

et al. 1972). The performance of

urea and other sources of N is 

being compared under forest conditions; currently, however, we cannot

specify circumstances where specific

fertilizers will provide the greatest

response per pound of nitrogen applied.

Stand age?--Biologic and economic

considerations determine when to

fertilize Douglas-fir stands. Fertilization at time of tree planting

has seldom been beneficial (Austin

and Strand 1960). Adding fertilizer

pellets to the planting hole has 

not proved cost-effective,and broadcast applications of nitrogen to

seedlings usually increase competition from other vegetation and

reduce seedling survival.

Because nutrient demands are 

usually highest when annual rates 

of wood production and crown expansion are highest, it is biologically

desirable to fertilize initially

when the Douglas-fir stand is between 15 and 20 years old. Although

this timing is likely to provide

large gains in wood volume, it may

not provide greater economic gains

than fertilizing at a later period

when the trees have reached a merchantable size. As we explain in

Part II, the period of time between

the fertilizer investment and the

harvest of volume gained from this

investment strongly influences 

economic benefits of fertilization.

IS FERTlLlZATlON A SUlTABLE TOOL?

Land managers can use several

criteria to judge the merits of 

fertilization. Specifically they

want to know how reliable forest

fertilization is, how environmentally

safe it is in the forested watershed, and how much economic return

it will provide. In the remainder

of Part I, we’ll see how well fertilization meets the criteria of

reliability and environmental impact.

In Part II, we’ll examine the economics of forest fertilization.

How Reliable is

Forest Fertilization?

Foresters want a tool that will

enhance growth over a wide range of

forest conditions, and they want a

high probability of getting improved

growth after using this tool.

PROBABlLlTY OF RESPONSE

some indication of the reliability

of nitrogen fertilization is provided

by results from the cooperative regional fertilization trials conducted

at numerous locations in western

Washington and Oregon by University

of Washington researchers (Atkinson

1974). Of 87 unthinned stands of

Douglas-fir tested, 72 percent responded with increased volume growth

of at least 10 percent within 2 years

of being fertilized with 200 pounds

of nitrogen per acre applied as urea

(Regional Forest Nutrition Research

Project 1975b). Moreover, the percentage of stands that showed at

least a l0-percent response to nitrogen was somewhat greater in lower than

higher site qualities:

This broadly based sample indicates

a 72-percent chance of obtaining at

least a l0-percent growth improvement

if nitrogen is applied to well-stocked

stands of Douglas-fir. These odds

can be improved if land managers can

identify the most and least profitable

acres for fertilization. Then, fertilizer expenditures can be programmed

selectively to increase reliability

and profits. Several means to increase reliability will be discussed

after describing some general effects

of nitrogen fertilization on Douglasfir.
6

EFFECTS OF NlTROGEN FERTlLlZER 

ON DOUGLAS-FIR GROWTH

Fertilized Douglas-firs usually

increase growth in diameter and 

volume during the first growing

season after treatment. Foliage of

trees with a severe nitrogen deficiency darkens, lengthens, and remains

on the tree for 1 or more additional

years. These changes in foliage and

greater branch growth indicate a

more rapid build-up of tree crown

and a greater potential for future

growth.

Response in volume growth generally peaks between the 3d and 5th

year after fertilization. Although

duration of response varies with

location, stand, and nitrogen dosage,

current data suggest that response

gradually approaches zero within 10

to 15 years after treatment.

Field trials during the past 25

years have demonstrated that addition of nitrogen usually increases

growth of Douglas-fir over the full

range of site qualities, sites I

through V. Initial results from 

the previously mentioned cooperative

trials in western Washington and

Oregon show that application of 200

pounds of nitrogen per acre to low

quality sites can provide a greater

cubic foot gain than the same application on higher quality sites

(Turnbull and Peterson 1976). During a 4-year observation period,

average yearly gains from fertilized

Douglas-fir stands ranged from 27

cubic feet on site I, through 91

cubic feet on site IV (table 2).

Thus far, an average of 108 to 364

cubic feet of extra wood was produced

by treatment; and these gains will

probably double during the future

growth of most of these stands.

The finding that low quality

sites provided a greater cubicfoot gain from 200 pounds of nitrogen per acre than higher quality

sites to the same dosage fits the

barrel analogy discussed earlier.

The most limiting growth factor on

these lower quality sites was evidently insufficient amounts of

available nitrogen. Fertilizing

with nitrogen temporarily removed

this limitation and, therefore,

increased stand growth. Conversely,

less response to fertilization

occurred on the naturally more productive sites, probably because

amounts of available nitrogen were

not limiting growth as severely.

lMPROVlNG RELlABlLlTY

As suggested by results from the

cooperative trials and earlier trials,

site index of Douglas-fir stands in

western Washington and Oregon is a

basis for predicting response to nitrogen fertilizer. Response is greater

and more likely on site IV land than

on progressively higher site qualities.

On site V and lower quality lands,

however, the likelihood of response

is less predictable for two reasons.

First, from an empirical standpoint,

fewer trials exist on such low sites

to establish a reliable prediction.

Second, from an intuitive standpoint

and based on the barrel analogy,

there is a greater likelihood that

several factors besides available

nitrogen will be at marginal levels

and therefore will limit growth.

A second option is also available

for predicting likelihood of fertilizer response. Chemical analysis of

soil or foliage from proposed treatment areas has been used successfully

in some agricultural crops and forest

types to predict need for fertilizer.

If close relationships exist between

growth and the content of nitrogen 

in foliage or soil, then one can
7

reasonably predict that increasing

the content of nitrogen by fertilization will enhance growth. Although such diagnostic techniques

are being developed by several 

scientists for use in Douglas-fir

(Lavender and Carmichael 1966

Shumway and Atkinson 1977),3/ they

are not yet sufficiently developed

for practical use.

Finally, the surest way to select

responsive areas for operational

fertilization is to match stand and

soil characteristics of successful,

experimental field trials (table 3).

Having assembled experience data, 

a land manager can increase his 

certainty of achieving similar gains

by fertilizing similar stands and

soils. The closer the match, the

more likely it is that similar gains

will be obtained.

How Environmentally Safe?

The evaluation of probable effects

of fertilization on the environment

should precede the decision to 

fertilize. As stated by Tamm (1973,

3/ Ian George Morison. Foliar nitrogen range and variability in a secondgrowth Douglas-fir forest and its relationship to certain stand and tree characteristics. Doctorate Dissertation. University

of Washington, Seattle. 268 p. 1970.

temporary increases in road and air

traffic and in audio and visual impacts are inherent to operational

fertilization. The predominant 

concern, however, is excessive nitrogen in surface and ground waters.

Specifically, increases in total

nitrogen concentration can increase

eutrophication, a natural but frequently nuisance growth of phytoplankton, algae, and aquatic weeds.

Moreover, concentrations of nitrate-N

exceeding 10 parts per million indicate the water is unfit for human

consumption (NAS-NAE 1973).

RESULTS FROM STREAM MONlTORlNG

Shortly after operational fertilization began in the Pacific Northwest,

stream waters flowing from several

forested watersheds in western Washington and Oregon were sampled before

and after applications of 150 or 200

p. 306), “There is no simple answer

to the question whether a forest 

fertilization improves or decreases

the environmental quality of a site.

Pros and cons have to be evaluated

and weighed at each site.”

Beneficial effects of fertilizing

Douglas-fir forests include temporary

improvements in vegetative color and

growth of trees and associated vegetation and faster rates of nutrient

cycling between the soil and the

Douglas-fir stand (Miller et al.

1976). Negative environmental impacts

are also probable. For example,
8

pounds of nitrogen per acre as urea

fertilizer. Initial results from

this monitoring were summarized in 

a 1972 report of the Environmental

Protection Agency (Groman 1972, 

p. 3):

“A continual process of collecting and evaluating forest

fertilization-water quality 

studies is required to supplement and refine current knowledge. The few studies conducted

to date indicate no substantial

or long-term detrimental effects

on the environment associated

with the practice....”

Water quality continued to be checked

and results from 22 fertilized watersheds in Douglas-fir forests were

reported by Moore (1974). He concluded that the maximum concentration of urea-, ammonia-, nitrite-,

and nitrate-nitrogen in streams that

were repeatedly sampled after forest

fertilization easily met published

standards for public water supplies.

The effects of increased nitrogen

on stream habitat and esthetics are

less definite. Thut and Hayden (1971)

concluded that these increases in

various forms of N found in streamwater after fertilization were well

below toxic levels for aquatic life;

they predicted that forest fertilization could increase aquatic productivity in nutrient-poor streams.

Since most streams in forest watersheds of the Douglas-fir region are

nutrient poor, this increase in

nitrogen concentration and aquatic

production could be considered environmentally desirable. Yet, 

fertilization could contribute to 

an undesirable condition outside 

the watershed, because increases 

in nitrogen concentration could

increase eutrophication after 

mountain streams enter warmer, 

slower-moving streams or lakes at

lower elevations. Clearly, the

extent of fertilization in a watershed and the stream characteristics

and land use downstream are key 

factors controlling the ultimate

effect of forest fertilization on 

the aquatic environment.

Direct measurements of nitrogen 

in streams suggest that forest fertilization is compatible with accepted

standards of water quality (NAS-NAE

1973). When reasonable precautions

were taken to minimize direct application of fertilizer to major streams,

increases in nitrogen content of the

water were primarily from fertilizer

that was inadvertently dropped into

small streams. Moore (1974 and 1975)

provided typical results from three

studies in stand conditions ranging

from old growth to a young plantation

(table 4). Helicopters applied 200

pounds of nitrogen as urea. Repeated

stream sampling during 29 and 52 weeks

after fertilization showed the equivalent of less than one-half of 1 percent of the applied nitrogen was 

lost to streams.
9

Nitrogen losses from fertilizer

landing on the soil or forest floor

are of less concern. Leaching losses

through soil to streams or ground

water occur primarily when nitrogen

is in the nitrate-ion form; therefore,

leaching may occur where ammonium or

urea fertilizers are converted to

nitrate by soil bacteria or if

nitrate-containing fertilizers are

applied. Although a laboratory

study showed that many forest soils

of the Pacific Northwest convert

fertilizer nitrogen and organic

nitrogen to nitrate ions (Heilman

1974), field investigations have

detected only small quantities of

nitrate in stream water after fertilization with urea (McCall 1970,

Burroughs and Froehlich 1972, Moore

1974 and 1975). Correspondingly 

low nitrate concentrations were

measured at the one location where

ammonium nitrate fertilizer was

applied (Moore 1974). Presumably,

applied or biologically converted

nitrate is readily taken up by soil

organisms and vegetation.

AVOlDlNG A POTENTlAL PROBLEM

Although additional information

is needed about the effects of

repeated fertilization to the same

area and about using fertilizer

solutions as foliar sprays (Norris

and Moore 1976, Miller and Young

1976), available information suggests that little environmental 

damage is likely if nitrogen 

fertilizer is carefully broadcast 

at current dosages and intervals 

on forested land. When undertaking

current operational practices, 

however, desirable precautions

include: (1) maintaining untreated

buffer areas along major streams;

this buffer should be recognizable

by the pilot and sufficiently wide

to reduce accidental drift of small

fertilizer particles, (2) avoiding

applications when spring snow melt

or heavy storms greatly expand small

tributary streams, and (3) suspending

operations whenever wind or reduced

visibility could lead to significant

losses of fertilizer from the target

area (Norris and Moore 1971)

ENERGY TRADE-OFFS

When fertilizing forests with

nitrogen, we expend nonrenewable

energy (fossil fuels, especially

petroleum and natural gas) to increase photosynthetic efficiency 

and thus wood production. For 

example, a conventional fertilization

requires the equivalent of about 50

gallons of oil to produce, transport,

and spread 200 pounds N per acre as

urea by helicopter. Conversely, we

can burn the additional wood gained

from fertilization to produce energy

or substitute this wood for metal 

or plastic products derived from 

nonrenewable resources. Several

authors discuss these energy tradeoffs and the means and economics of

obtaining them (Grantham and Ellis

1974, Grantham et al. 1974, Evans

1974, Boyd et al. 1976)

Reifsnyder and Lull (1965) and

Smith and Johnson (1977) maintained

that growing wood, especially in

conifer forests, is one of the most

efficient ways to use energy to 

capture more energy. Assuming a

return of 2 cubic feet of wood per

pound of N applied as urea fertilizer,

Smith and Johnson (1977) estimated

a gross return of about 12 units of

energy for each unit invested in 

fertilization of Douglas-fir forests.

This gross return is converted to 

net return by subtracting the energy

necessary to harvest (Dykstra 1976)

and supply the final product (National

Academy of Sciences 1976)

For example, assuming (1) 200

pounds of N/acre produces an additional 400 cubic feet/acre of Douglasfir roundwood and (2) each 100 

cubic feet of green roundwood is

equivalent to 3.3 barrels or 139 

gallons of fuel oil (Hartman et al.,

n.d.), then the gross energy return

from fertilization is 556 gallons 

of oil. Further, assuming 5.16 

gallons of oil to harvest 1 cord of

roundwood (American Pulpwood Association 1975) at 85 cubic feet of

solid roundwood per cord, then harvesting this extra 400 cubic feet

would require 24 gallons of oil and

thus reduce the net energy return 

to 532 gallons of oil-equivalent 

for expenditures of 50 gallons to

produce, transport, and spread 200
10

pounds of N per acre by helicopter.

Therefore, the net ratio of energy

gain in this example is 10.6.

Summary

The four major points of Part I

follow:

1. Fertilization with nitrogen

is a reliable means for increasing

wood production in most Douglas-fir

forests.

2. Current operational fertilization is based on past research

findings. From 1965 through 1974,

at least 825,000 acres of established

stands of Douglas-fir in western

Washington and Oregon were fertilized.

The usual treatment consisted of 

150 to 200 pounds of elemental nitrogen per acre applied as urea by 

helicopter during late fall through

early spring.

3. Experimental trials indicate

that land managers can reasonably

expect from 200 to 800 additional

cubic feet of stem wood per acre

from fertilizing commercial forests.

Results from cooperative trials 

show that gains in cubic volume 

from fertilizing Douglas-fir stands

are inversely related to site quality.

Thus, application of 200 pounds of 

N per acre to site IV and III stands

can provide a greater cubic-foot

gain than the same application on

higher quality sites. Continuing

efforts by researchers and land 

managers can improve volume and

financial gains from forest fertilization.

4. Environmental damage is unlikely if fertilizer is carefully

broadcast to minimize direct application into major streams.

PART II. How Economic?

Forest managers want a financial

gain or profit from their investments in fertilization. This goal

is reached when revenue gained from

fertilizing exceeds the total costs

of fertilizing. In this section,

we shall first show how various 

factors influence economic returns.

We will then present a break-even

analysis to show how many cubic feet

of extra growth are required and what

stumpage prices are necessary to pay

for assumed costs of fertilization.

Finally, we’ll discuss other financial considerations affecting fertilization decisions.

Treatment Costs

Costs of fertilizing clearly affect

the profit from this silvicultural

practice. The total cost has two

components--the initial cost of fertilizing and the interest charges 

for carrying this investment.

lNlTlAL COSTS

The initial costs of fertilizing

include the contract costs (supplying

the fertilizer, transporting it into

the forest, and applying it to specified areas by helicopter), and the

costs of administering the contract,

providing access roads and heliports,

and in some instances, assessing

water quality and tree response.

Since the cost of fertilizer is 

usually 60-70 percent of the total

treatment costs, the price of fertilizer strongly influences the initial

cost of treatment.

Past costs of fertilization varied

widely from year-to-year and from

job-to-job. In 1970, the total cost

of applying 200 pounds of nitrogen

per acre averaged about $23. By 1974,

when worldwide fertilizer and petroleum shortages developed, average

costs more than doubled to about 

$57 per acre. On the income side of

the financial ledger, however, stumpage

prices increased by an even greater

amount during the same period, so

fertilization appeared to be a more

attractive investment in 1974 than 

in 1970 (fig. 4)

One can minimize costs of a fertilization contract in at least two ways.

As with most goods and services, the

seasonal price for both fertilizer

and application reflect supply and

demand. Due to seasonal demands in

agriculture, fertilizer prices are

usually 3 to 5 percent lower in fall

and winter. Application costs, however,
11

are generally much lower in spring,

because many helicopters are contracted in fall for forest fire 

suppression. The net result is that

fertilization contracts usually cost

slightly less in spring.

second way to reduce costs is 

to include as many acres as possible

in the contract. Costs of fertilization per acre generally decline

as the size of the contract increases.

One experienced Northwest contractor 

estimated that his bid per acre

would be 20 percent less in a 2,000

ton contract involving 9,200 acres

than in a 100-ton contract involving

460 acres.

In the economic analyses that

follow, an average initial treatment

cost of $60 per acre will be used.

This approximates the cost of applying 200 pounds of nitrogen per acre

in the form of 435 pounds of urea

fertilizer on 7,400 acres of the
12

Willamette National Forest in 1976.

To illustrate the effects of a lower

initial cost, a $40 per acre treatment cost will also be used.

INTEREST CHARGES

The compound interest costs of

carrying the initial investment

strongly affect profits gained from

fertilization and other intensive

management practices. As consumers,

we know that such carrying charges

are based on interest rate and

duration of the loan. Although the

market rate of interest may be 12

percent, the real rate of interest

is less because the rate of inflation

must be subtracted from it. For

example, if one borrows money at 

the market rate of 12 percent and

the annual rate of inflation is 5

percent, then the real rate of interest is only 7 percent.

During a l0-year period, a fertilization cost of $60 borrowed at a 

real rate of 7 percent almost doubles

to a cost of $118 (fig. 5). If 

carried 20 years, it doubles again 

to $232 or almost four times the 

initial cost. Therefore, to break

even, the increase in value of wood

harvested from the fertilized stand

must equal $118 if harvested in 10

years and $232 if harvested in 20

years.

In the economic analyses that 

follow, we selected 10 and 20 years

as investment periods. We assumed

that most of the volume gained from

fertilization would be accumulated 

in 10 years and that this extra 

volume could be cut and sold at that
13

time. But harvesting trees 10 years

after treatment is only reasonable

if fertilizer is applied to a stand

that is merchantable or nearly merchantable. If smaller trees are

fertilized, then a longer investment period is necessary until crop

trees reach merchantable size.

Figure 6 shows the total cost of

fertilization when initial costs of

$60 and $40 per acre are compounded

at 7-percent interest. Notice that

the total or cumulative cost for a

$60 initial cost is 1-1/2 times 

that for a $40 initial cost.

Revenue

The land manager who invests in

forest fertilization anticipates

increased growth and, therefore,

increased revenue from his forest.

Investment is profitable when the

increased revenue exceeds the attendant costs.

VOLUME GAlNED

The extra wood attributable to

fertilization increases revenue when

it is harvested and sold. The additional revenue gained from fertilization depends on the amount of extra

volume and its price per unit. For

the landowner who sells only stumpage,

this extra revenue is obtained from

having more volume to sell. For

landowners with manufacturing facilities, however, additional revenue 

can accrue because this extra volume

may reduce a need to purchase higherpriced wood on the open market.

The extra volume of wood gained

from fertilization and how soon this
14

Although growth is more precisely

measured in cubic feet, cubic-foot

prices are seldom used. To estimate

the stumpage value of extra cubic feet

produced after fertilization, one must

convert conventional stumpage prices

per thousand board feet, Scribner

scale, to a price per cubic foot

(Fahey and Woodfin 1976).4/

The number of board feet recoverable from a cubic foot of wood and

the price per board foot are both

strongly dependent upon tree size

(table 6). Therefore, the price 

paid per cubic foot is higher for

large diameter logs than for small

logs. This difference in pricing

means that a 300-cubic foot gain 

per acre from fertilization might

return two times as much stumpage

revenue to the landowner if he harvested 16-inch trees instead of 8-inch

trees.

The extra wood produced from 

fertilization will be harvested years

after this treatment is applied. To

compute financial gains from treatment, one can estimate the future

price of this extra wood by selecting an appropriate current stumpage

price and projecting an annual rate

of price increase. The average price

for Douglas-fir stumpage on National

4/ To convert stumpage values in board

feet (BF) to cubic feet (CF):

wood can be harvested strongly affect

the revenue gained from the investment. Where natural productivity 

is restricted by nutrient deficiencies, fertilizers not only increase

usable yields, but also enable land

managers to make earlier commercial

thinnings and final harvests.

In Part I, we described the effects of nitrogen fertilizer on

growth of Douglas-fir. Experimental

trials indicated that land managers

can reasonably expect from 200 to

800 additional cubic feet of stemwood per acre over a l0-year period

after applying 150 to 200 pounds of

nitrogen per acre. Moreover, the

cubic foot gains in total stem 

volume were more on sites of low

natural productivity than on sites

of high natural productivity 

(table 2)

STUMPAGE PRlCE

The stumpage price paid to the

forest owner is the residual or net

value after the costs of logging,

loading, and hauling are subtracted

from the price paid for logs at the

mill, which is the usual delivery

point. Large trees have more stumpage value because the price paid at

the mill increases while the costs

of harvesting decrease (Worthington

and Staebler 1961, Adams 1965, 

Adams 1967, Worthington 1966).

Therefore, the landowner receives 

a higher stumpage price for selling

larger trees (table 5)
15

Forests in western Washington and

Oregon has increased substantially

over the last decade. Even when

prices are converted to constant

dollars to remove general inflation,

a substantial increase in real price

is evident (table 7). Based on

these regional prices and long-term

lumber prices nationally, we assumed

a 2-percent annual increase in the

real value of stumpage. This is

probably a conservative estimate of

the long-term trend.

For our analysis, we want to ignore

general inflation because it reduces

the purchasing power of the dollar 

by an amount that offsets the increases

in revenue. One can readily see, 

however, that a long-term increase in

the price of wood which exceeds general inflation will increase the attractiveness of investments that produce

more wood. Therefore, these increases

in the real price of wood must be

included in an economic analysis.

We consider two ways to accommodate

increases in real price. If we included them by projecting current

prices at a 2-percent rate of increase,

we would have stumpage prices that

differed every year. To avoid this

inconvenience, we lowered the interest

rate on the fertilization investment

to adjust for the expected 2-percent

increase in the real price of wood.

Consequently, we could use today’s

prices in our analyses. Notice that

“today’s prices” means current stumpage

prices at the time you are performing

an economic analysis.

Our procedure is simply a second

reduction in interest rates. Recall

that we first adjusted market rates 

of interest to real rates of interest

to remove the general effects of inflation. We now calculate an effective

rate of interest to incorporate the

rate of increase in the real price
16

of wood. By simple subtraction, we

reduce the real rate of interest by

the rate of increase in the real

price of wood.5/ In our example, 

the real rate of interest is 7 percent and the rate of real price increase is 2 percent; therefore, the

effective rate of interest is 5 percent. Cumulative costs based on

other effective rates of interest

are provided (Appendix A)

Using an effective rate of interest will make it easier to compare fertilizer investments. Notice,

however, that this effective rate 

of interest does not show the full

return on the investment. The full

return from the fertilizer investment has two components: the in5/ Although this is not precisely correct (Flick 1976), the bias is negligible

in the range of interest rates relevant 

to this kind of analysis.

creased volume of wood and the

increase in the real price of that

extra wood. Therefore, the full

return on investment for our breakeven analysis is 5 percent plus 

2 percent, or 7 percent.

To compare this full rate of 

return from a fertilization investment with other investments such as

stocks and bonds, one must subtract

the expected rate of inflation from

the market rate of return of stocks

and bonds. For example, with inflation estimated at 6 percent, a 

bond yielding a l0-percent market

rate has a net rate of 4 percent 

compared to the 7 percent of our

break-even analysis.

We get a lower cumulative cost 

when we use an effective rate of

interest to project treatment costs.

This is an adjusted cost (fig. 7)
17

The broken line shows a $60 treatment cost that became a cost of

818 after 10 years. The solid

line shows that a $60 treatment 

cost expands to an adjusted cost of

$98. When we use the effective rate

of interest, we have automatically

incorporated our assumed 2-percent

annual increase in the real price 

of wood. In effect, we have offset

part of the cumulative cost of fertilization by the anticipated increase in the real price of wood.

Revenue Required to Break Even

Now we will put these economic

definitions and principles into

practice by answering some practical

questions about the economics of

forest fertilization. Appendix B

includes a sample worksheet supporting some of these examples and 

a blank form that can be used for

other analyses. You will see what

combinations of stumpage prices and

extra yields will provide a breakeven return from a specified investment in forest fertilization. We

have a break-even situation if we

specify in our analysis that the

revenue should equal the total costs.

A profit, however, is indicated if

anticipated revenue exceeds the

break-even revenue. One can estimate

this profit by using more complex

methods of economic analysis

(Regional Forest Nutrition Project

1975a, 1977)

WHAT BREAK-EVEN VOLUME?

What extra volume from fertilization is necessary to break even? 

The curving line in figure 8 shows

the various combinations of stumpage prices and volumes that will produce a $98 revenue. Recall from

figure 7 that a $60 initial cost compounded at 5-percent effective interest rate for 1O years equaled $98.
18

Notice that the amount of extra

volume needed to break even depends

on the stumpage price; lesser volumes are needed when stumpage prices

are high.

For example, stumpage price for

trees averaging 8-inch d.b.h. at

harvest was estimated at 25 cents

per cubic foot and for trees averaging 16-inch d.b.h. was 60 cents

(table 6). Using these stumpage

prices, we see that the break-even

volume from 8-inch trees is 392

cubic feet and 163 cubic feet if

harvested from 16-inch trees

(fig. 8). This clearly illustrates

the economic advantage of increasing growth of larger trees and harvesting gains from larger trees.

Lower initial costs of treatment

reduce the break-even volume. As

discussed previously, several factors can lower initial cost of

treatment. These include fertilizing

large contiguous acreages, applying

lesser amounts of fertilizer, or negotiating a contract when the demand for

fertilizer or applicators is low.

Assume that initial cost can be reduced from $60 per acre to $40. Whereas the $60 cost increases to $98 after

10 years, the $40 cost increases to

only $65, as shown by the broken line

(fig. 9). Therefore, a lesser volume

will cover these reduced cumulative

costs. For example, assuming a current stumpage price of 60 cents per

cubic foot, 108 additional cubic 

feet would be necessary to offset a

$40 treatment cost, compared to 163

cubic feet to offset a $60 initial

cost.

Finally, by lowering the carrying

charges, one can reduce the breakeven volume. Fertilizing mature trees

is one way to do this, because commercial thinning or final harvests
19

can remove extra volume within 5 to

10 years after fertilization. In

figure 10, the solid, curving line

again indicates the $98 revenue

necessary to cover a $60 treatment

cost when carried for 10 years at

5-percent compound interest. If

harvest is delayed for 20 years

after fertilization, however, this

initial cost expands to $159.

Therefore, more volume is necessary

to break even.

For example, if we fertilize a

stand averaging 6-inch d.b.h. and

waited 10 years until crop trees

averaged 8 inches with an estimated

stumpage value of 25 cents per

cubic foot, we would need 392 cubic

feet to break even (fig. 10). Now

compare this volume to the 636 cubic

feet necessary for another land

manager who fertilizes 3-inch trees

and must wait 20 years for the

increase to be harvested from 8-inch

trees. Doubling the investment period

increases the total cost from $98 to

g59 per acre. Therefore, 636 cubic

feet instead of 392 would be necessary to break even.

WHAT BREAK-EVEN PRICE?

Now, let us use these same curves

in a different way. Based on existing data from fertilized stands

(table 3), some managers can estimate

the amount of extra volume they expect from fertilizing a specific

stand. Therefore, they can judge

the economic feasibility of fertilization by determining the current

stumpage price needed to break even.

The same procedure used to estimate

break-even volume can also be used 

to find the break-even price. First,
20

estimate the gain in salable volume

from fertilization and the years

between fertilization and harvest,

i.e, the period of investment.

Second, determine the total cost of

fertilization for a specified initial

cost and the estimated period of investment. Third, use the graph of

price-quantity combinations to

estimate the current stumpage price

necessary to offset this cumulative

cost. If this estimated stumpage

price is less than would be anticipated for the current market, then

the break-even price is exceeded

and a profit is indicated. An

example will clarify this.

Assume a harvest of 500 cubic

feet per acre 10 years after fertilization. An initial treatment

cost of $60 per acre will expand 

to a total cost of $98 in 10 years.

Therefore, a stumpage price of 20

cents per cubic foot would be necessary to offset thiS cumulative cost

(fig 11). A profit is indicated

if current stumpage price exceeds 

20 cents per cubic foot (the breakeven price).

The preceding examples can be 

verified using the worksheet

(Appendix B), the table of multipliers (Appendix A), and the graph 

of price-quantity combinations

(Appendix C). Reworking these 

examples will check your understanding of the procedure before solving

other problems of your choosing. 

A worksheet with data inserted from

some of the sample problems is

included as well as a blank form for

solving other problems.
21

Other Financial Considerations

The effect of income taxes, the

timing of cash flow, and other factors to be included in investment

decisions are discussed below.

EFFECT OF lNCOME TAXES

Our previous discussion and 

examples were directed toward obtaining a break-even analysis on a

before-tax basis. Forestry and 

nonforestry investments should, 

however, be compared on a beforeand after-tax basis. Net income

from the timber sale will ordinarily

be taxed as a capital gain rather

than as ordinary income. This

reduces the tax effect, because

part of the income is tax exempt.

Thus, the effect of taxation on

forestry investments is often less

than it is on most other investments.

Costs and revenues could be

entered on the accompanying worksheet on an after-tax basis by

adjusting them for tax effects. 

The result would be a break-even

analysis on an after-tax basis 

that could be compared to other

investments on an after-tax basis.

More detailed procedures for doing

that, however, are beyond the scope

of this report.

CASH FLOW MANAGEMENT

As anyone with a checking account

and financial obligations knows, cash

flow management requires some attention. Negative balances are not

tolerated for long and penalty costs

are associated with them. Cash flow

management by forest landowners poses

similar problems. Some landowners

have ready access to outside sources

of investment capital while others

do not. Those without ready access

to capital must pay particular attention to cash flow management. Even

those with ready access to capital

must manage cash flows carefully,

because the cost of borrowing 

capital is usually higher when it

comes from outside sources. For

most landowners, financing new

investments out of accumulated

savings or current income is probably

the least costly method of financing.

Therefore, forest landowners should

consider timing receipts from timber

harvest to provide cash needed for

investments like fertilization. In

some circumstances, altering the 

timing of commercial thinning or

final harvest to coincide with needs

for cash may be the most attractive

method of financing.

CASH FLOW EFFECTS

Our economic analysis relates to

fertilizing a specific stand of trees.

Costs are incurred when a stand is

fertilized. Subsequently, interest

charges accrue on this investment.

Revenue is received when the fertilized stand is thinned or harvested.

This sequence of activities closely

approximates the cash flow that

results from fertilization investments for many private and some 

public forest managers. The effect

of fertilization on the cash flow

from some forests, however, may be

very different.

On most public lands, the policy

is to provide a non-declining flow

of wood from the forest. This policy

makes current harvests sensitive to

current and future growth rates.

Mature or overmature stands in

the forest inventory provide flexibility to harvest immediately extra

growth gained from treating immature

stands. For example, when growth 

is increased by fertilizing young

stands, the harvest and resulting

cash flow from mature stands may

increase immediately. The increase

in current harvest that occurs before

any treated stands are actually harvested is called the “allowable cut

effect” (Schweitzer et al. 1972).

It is widely recognized that the

allowable cut effect occurs. It is

also widely recognized that the 

immediate increase in current harvest and cash flow is the result of

increasing the growth on future

stands. Clearly, this immediate

increase in cash flow does not 

come directly from the sale of wood

that is produced by the fertilizer.

Yet, through the allowable cut effect,
22

fertilization can increase harvest

level and cash flow.

Understandably, there is disagreement and controversy over the consideration that should be given to

this immediate cash flow increase 

in ranking alternative investments 

in forest management (Lundgren 1973,

Teeguarden 1973). Furthermore, the

magnitude of the allowable cut 

effect does not have a predictable

relationship to the increases in

future growth (Bell 1976). The

allowable cut effect can be reliably

estimated only by making a series 

of allowable harvest calculations

and then comparing them. Because

of these limitations, it is probably

unsafe to consider the allowable cut

effect in investment decisions without t~e counsel of someone knowledgeable in the economic theory that

supports benefit-cost analysis. 

The immediate increase in cash flow,

however, that would accompany a 

fertilization program is a consequence that decisionmakers should

recognize.

Summary

The seven major points of Part II

follow:

1. The total costs of fertilization include the initial costs of

fertilizing and the interest charges

on this investment.

2. Because of the nature of compound interest charges, fertilizing

stands that will be harvested in 10

years will generally be more profitable than fertilizing stands that

will be harvested after a longer

investment period.

3. Because larger trees bring 

a higher price than smaller trees,

fertilizing larger trees will generally be more profitable than 

treating smaller trees on sites of

equal productivity.

4. Because of the greater growth

increases reported for low-quality

sites after fertilization, fertilizing trees on these poorer sites will

generally be more profitable than

treating trees of the same size on

sites of higher natural productivity.

More precise statements about setting

priorities among stands for fertilization require more detailed information

and analysis.

5. A projected long-term increase

in the price of wood which exceeds

general inflation will increase the

attractiveness of fertilization and

other investments that produce more

wood.

6. Timing of receipts from timber

harvests to coincide with cash needs

for fertilization will often be the

least costly method of financing.

7. Fertilization can be an economically attractive way to increase

wood production of Douglas-fir forests.

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1975. Fuel requirements for har

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D.C.

Adams, Thomas C.

1965. High-lead logging costs as

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For. and Range Exp. Stn., Portland,

Oreg.

Adams, Thomas C.

1967. Production rates in commercial thinning of young-growth

Douglas-fir. USDA For. Serv.

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1974. Forest fertilization research

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1973:199-220, illus.

Austin, R. C., and R. F. Strand. 

1960. The use of slowing soluble 

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Bell, Enoch F.

1976. Yes, increased yields can 

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Portland, Oreg.
23

Boyd, Conor W., Peter Kock, Herbert

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1976. Wood for structural and 

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A. Froehlich.

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Dykstra, Dennis P.

1976. Production rates and costs 

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Ellis.

1974. Potentials of wood for producing energy. J. For. 72(9):

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Heilman, Paul.

1974. Effect of urea fertilization

on nitrification in forest soils

of the Pacific Northwest. Soil

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1966. Effect of three variables on

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441-446.
24

Lee, Y. Jim.

1974. Four-year basal area growth

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1973. The allowable cut effect. 

Some further extensions. J. For.

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to spend on forest fertilization?

An economic model. In Regional

Forest Nutrition Research Project

Biennial Report 1972-1974. 

p. 28-31. Coll. For. Resour.,

Univ. Wash,, Seattle.
25

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summaries. In Regional Forest

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Univ. Wash., Seattle.

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Project.

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nitrogen fertilizer. In Regional

Forest Nutrition Research Project

Biennial Report 1974-1975. 

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Univ. Wash., Seattle.

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W. Lull.

1965. Radiant energy in relation

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1977. Production, prices, employment, and trade in Northwest

forest industries, 4th quarter

1976. 54 p. Pac. Northwest

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Sassaman, and Con H. Schallau. 

1972. Allowable cut effect: 

some physical and economic implications. J. For. 70(7):

415-418.

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1977. Measuring and predicting

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Olympia, Wash.

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20 p., illus. Portland, Oreg.

Steinbrenner, E. C.

1968. Research in forest fertilization at Weyerhaeuser Company

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1973. Effects of fertilizers on 

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1973. The allowable cut effect: 

A comment. J. For. 71(4): 

224-226.

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1976. Analysis of Douglas-fir 

growth response to nitrogenous

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1966. Labor requirements in thinning Douglas-fir and western

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26

Appendix A
27

Appendix B

Worksheet for determining break-even volume or stumpage price 

Known or assumed

1. Initial cost of fertilizing $ per acre

2. Years to next commercial cut years

3. Average d.b.h. of trees to be harvested inches

4. Market rate of interest percent

5. Rate of inflation percent

6. Rate of increase in real price of stumpage percent

Compute or determine

7. Effective rate of interest percent

(Item 4 - Item 5 - Item 6)

8. Cumulative cost of fertilizing $ per acre

(Item 1 X multiplier from Appendix A)

9. Break-even volume

A. Assumed stumpage price $ per cubic foot

(Table 6 or supply your own)

B. Volume needed to break even cubic feet per

(Read from Appendix C or acre

item 8 ÷ item 9A)

10. Break-even price

A. Assumed volume gain cubic feet per

(Tables 2 and 3 or supply your own) acre

B. Stumpage price needed to break even $ per cubic foot

(Read from Appendix C or 

item 8 ÷ item 10A)
28

Worksheet for determining break-even volume or stumpage price 

Known or assumed

1. Initial cost of fertilizing $ per acre

2. Years to next commercial cut years

3. Average d.b.h. of trees to be harvested inches

4. Market rate of interest percent

5. Rate of inflation percent

6. Rate of increase in real price of stumpage percent

Compute or determine

7. Effective rate of interest percent

(Item 4 - Item 5 - Item 6)

8. Cumulative cost of fertilizing $ per acre

(Item 1 X multiplier from Appendix A)

9. Break-even volume

A. Assumed stumpage price $ per cubic foot

(Table 6 or supply your own)

B. Volume needed to break even cubic feet per

(Read from Appendix C or acre

item 8 ÷ item 9A)

10. Break-even price

A. Assumed volume gain cubic feet per

(Tables 2 and 3 or supply your own) acre

B. Stumpage price needed to break even $ per cubic foot

(Read from Appendix C or 

item 8 ÷ item 10A)
29

Appendix C

GPO 987-439
The mission of the PACIFIC NORTHWEST FOREST AND

RANGE EXPERlMENT STATlON is to provide the knowledge, technology, and alternatives for present and future

protection, management, and use of forest, range. and related

environments.

Within this overall mission the Station conducts and 

stimulates research to facilitate and to accelerate progress

toward the following goals: 

1. Providing safe and efficient technology for inventory, 

protection, and use of resources.

2. Developing and evaluating alternative methods and levels 

of resource management.

3. Achieving optimum sustained resource productivity 

consistent with maintaining a high quality forest 

environment.

The area of research encompasses Oregon, Washington.

Alaska, and, in some cases, California, Hawaii. the Western

States, and the Nation. Results of the research are made 

available promptly. Project headquarters are at:

Anchorage, Alaska 

Fairbanks, Alaska 

Juneau, Alaska 

Bend, Oregon 

Corvallis, Oregon

Mailing address: Pacific Northwest Forest and Range 

Experiment Station 

809 N.E. 6th Ave.

Portland, Oregon 97208

La Grande, Oregon 

Portland, Oregon 

Olympia, Washington 

Seattle, Washington 

Wenatchee, Washington