Microcomputer Software for

Calculating the Western Oregon

Elk Habitat Effectiveness Index

Alan Ager and Mark Hitchcock
Erratum

Publication: Microcomputer Software for Calculating the

Western Oregon Elk Habitat Effectiveness Index, PNWGTR-303, September 1992

Authors: Alan Ager and Mark Hitchcock

Software: The HEIWEST software can be obtained at

http://www.fs.fed.us/r6/uma/projects/tools/
ALAN AGER is an operations research analyst, U.S. Department of Agriculture, 

Forest Service, Umatilla National Forest, 2517 Hailey Avenue, Pendleton, Oregon 

97801; and MARK HITCHCOCK is a consulting forester, 2347 Old Day Creek Road, 

Sedro Woolley, Washington 98284.

This work is part of cooperative agreement PNW89-648 for the Starkey Research 

Development and Application Program between the Pacific Northwest Research 

Station and the Pacific Northwest Region of the Forest Service.

Authors

This paper describes the microcomputer program HEIWEST, which automates calculation 

of the western Oregon elk habitat effectiveness index developed by Wisdom and others 

(1986). The western Oregon HEI model measures habitat quality for Roosevelt elk (Cervus 

elaphus roosevelti), and is one of several HEIs used in the Pacific Northwest and 

elsewhere to evaluate and monitor elk habitat (Black and others 1976; Thomas and others 

1979, 1988).

HEIWEST performs all the calculations required by the HEI model, including the spatial 

analysis of cover and forage areas. The program requires little or no training to operate and 

can be used to quickly measure HEI as part of project planning or monitoring efforts. It is 

especially useful in project analyses where several silvicultural alternatives must be 

evaluated for their effects on elk habitat. The program also can be used to calculate interior 

habitat and edge length for indices of forest fragmentation (Harris 1984). Habitat maps for 

HEIWEST can be derived from a GIS (geographic information system), such as the 

MOSS/MAPS used by the Forest Service in the Pacific Northwest Region, or be manually 

input from within the program. The HEIWEST program and example data are included on a 

diskette distributed with this paper.

The HEIWEST program calculates HEI from coefficients of habitat use published by 

Wisdom and others (1986). This model evaluates four habitat components: the size and 

spacing of forage and cover areas, the density of roads open to vehicular traffic, the 

quality of cover, and the quality of forage. Each is measured with subindices that can 

range from 0.0 (no value) to 1.0 (optimum condition). The HEI is computed as the 

geometric mean of these subindices as follows:

HEIsrfc = (HEs x HEr x HEc x HEf)1/N ,

where

HEs = habitat-effectiveness index derived from size and spacing of forage and cover 

areas,

HEr = habitat-effectiveness index derived from the density of roads open to vehicular 

traffic,

HEc = habitat-effectiveness index derived from the quality of cover,

HEf = habitat-effectiveness index derived from the quality of forage, and

1/N = Nth root of the product taken to obtain the geometric mean where N = the 

number of habitat variables.

See Wisdom and others (1986) for additional details. The HEIWEST program was 

developed to quantitatively replicate as closely as possible this model.

HEIWEST is written and compiled in TURBO Pascal version 6.0 and operates on 

IBM-compatible microcomputers with DOS version 2.0 or later1. HEIWEST automatically 

detects the type of video display installed (for example, monochrome, VGA, EGA, CGA)

and takes advantage of the capabilities of each. A 1.2 megabyte (MB) floppy drive is 

required to read the distribution diskette. HEIWEST prints to most printers by using the 

standard ASCII printer control characters to control formatting.

'The use of trade or firm names in this publication is for 

reader information and does not imply endorsement by the 

U.S. Department of Agriculture of any product or service.

TURBO Pascal is a registered trademark of Borland 

International, Scotts Valley, CA.

Getting Started

Hardware Requirements

The Western Oregon 

HEI Model

Introduction
Random Access Memory (RAM) requirements depend on project area size; at least 

130 kilobytes (KB) must be available to load the program and process habitat maps 

having 60,000 pixels (31,000 acres for maps with 50- by 50-yard pixels). Larger maps 

require more memory. The maximum map size accommodated by the program, 600 

columns by 800 rows (ca. 240,000 acres at 50- by 50-yard pixels), requires 540K 

RAM. A math coprocessor and a mouse with a Microsoft-compatible driver are 

optional equipment.

The distribution diskette contains five files. HEIWEST.EXE is the executable program 

for calculating HEI. WEST.MAP and WEST.DB are a sample habitat map and a 

database, respectively. HEIUTIL.EXE is a utility program that facilitates the conversion 

of MOSS-MAPS GIS data to the HEIWEST format. B.COM is a file-browsing utility that 

can be used in conjunction with HEIUTIL.EXE.

No special installation routines are necessary to run HEIWEST or the accessory 

programs. They can be run directly from the distribution diskette or copied onto a hard 

drive. It is convenient to create a subdirectory (for example, C:\HEI) on the hard drive 

into which the files can be copied and the program executed.

HEIWEST.EXE calculates HEI components from a digital habitat map and numerical 

data on open road mileage. Open road mileage is entered from the keyboard with 

each HEIWEST session by using menu options. Cover and forage data are derived 

from a habitat map constructed for each project area. The habitat map is an ASCII 

computer file in which an original line map has been translated into a grid of square 

pixels of a fixed area. The pixel size can be set by the user, the maximum size being 

100 yards on a side (2.066 acres). The habitat type of each pixel (for example, optimal 

cover, thermal cover, hiding cover, and forage) is represented by one of 12 habitat 

codes (table 1). As an example, figure 1A shows the map published by Wisdom and 

others (1986, p. 23), and figure 1B shows the same map in HEIWEST format.

Program Overview

Installation

2
3
The calculation of the individual HE components by the HEIWEST is described briefly 

below. Refer to Wisdom and others (1986) for details.

The HEs subindex used to measure the size and spacing of forage and cover areas is 

calculated by HEIWEST with a search algorithm that moves to each pixel on the map and 

determines the linear distance to the nearest pixel of opposite habitat type (forage versus 

cover). The distance is used to classify the pixel and associated acreage for the distance 

bands. The HEs is then calculated by using the weighting factors as described in Wisdom 

and others (1986). The classification of pixels into distance bands is illustrated in figure 2 

for the example map in figure 1.

The HEr to measure the effect of open road density is calculated according to Wisdom and 

others (1986, figure 8) with equations developed by Lyon (1983). The appropriate equation 

depends on the road density. If the road density (RD) is less than 1.1 miles/mile 2 then,

HEr = 0.4 + [(6 - RD)/6]6 x 0.6.

If the road density is greater than or equal to 1.1 miles/mi2 but less than 2 miles/mile2 then,

HEr = 0.486 + 0.092 x (2-RD)/0.89.

If the road density is greater than or equal to 2 miles/mile2 but less or equal to 6 miles/mile2

then,

HEr = 0.104 + (6-RD)/4 x 0.382.

If the road density is greater than 6 miles/mile2 then HEr = 0.104.

Hence, an analysis area with no open roads has an HEr value of 1.0. An open road density 

greater than 6.0 has an HEr value of 0.104.

The HEc to measure the quality of cover is calculated as the weighted proportion of cover 

occupied by each habitat type, as described in Wisdom and others (1986, p. 28). The 

proportion of area in each cover type is multiplied by a weighting factor and summed. The 

weighting factors are 1.0 for optimal cover, 0.5 for thermal cover, and 0.1 for hiding cover.

The HEf to measure the quality of forage is calculated as the weighted proportion of forage 

in each of the forage types, as described in Wisdom and others (1986, p. 29). The 

proportion of area in each forage type is multiplied by a weighting factor and summed. See 

Wisdom and others (1986, p. 29) for the weighting factors.

This section provides instructions to demonstrate the HEIWEST program and its 

capabilities. Insert the distribution diskette in the A: drive and type "HEIWEST". Press any 

key after viewing the opening screen. Note the help window, which contains program 

operation and calculation parameters. The "PgUp" and "PgDn" keys are used to browse 

through six pages of help information. The help window can be activated from elsewhere in 

the program by pressing the "F1" key. The "Esc" key is used to close the help window. 

Press the "/" key to obtain the main menu. Selections from this menu are activated by 

typing the capitalized letter of each menu option. Load the sample map by selecting the 

"Map" and "Load" menu options (type "M" and "L"), and then type "WEST.MAP". Press the 

"Enter" key and the sample map will load and appear on the screen. Each code on the map 

represents a square pixel of 50 yards on a side 0.517 acre). The codes displayed on the 

map represent various habitat types

Methods Used by

HEIWEST for

Calculating HEI

A Quick Demonstration

4
5
as indicated in table 1. The cursor location can be changed by pressing the four arrow 

keys. In the lower left corner, the definition of the habitat code is displayed for the current 

position of the cursor.

The habitat map contains the information required to calculate three of the four habitat 

parameters—HEs and HEc and HEf—which measure the size and spacing of the cover 

and forage areas, cover quality, and forage quality, respectively. Information to calculate 

the HEr for roads is input for each map by choosing "Options" and "Roads" and entering 

an open road mileage. HEI now can be calculated by choosing "Run" from the main 

menu. The results will be sent to the screen (fig. 3) and can be sent to a printer or file by 

entering the appropriate response to the prompt.

To see the what-if capabilities of HEIWEST for timber sale planning, use the arrow keys 

to position the cursor within an area of cover habitat (map code "A", "B", or "C"). Harvest 

treatments can be applied to habitat maps by changing map codes to "4" (clearcut) with 

either the keyboard or the mouse. Clicking the left mouse button will change the habitat

code at the mouse cursor to the last code entered from the keyboard. Each pixel that is 

changed represents treating of 0.517 acre. When a harvest unit has been outlined in this 

manner, run HEIWEST again to see changes in the HEI that have resulted from the 

treatments. Each alternative developed in this manner can be saved in a separate habitat 

map by choosing "Map" and "Save" from the main menu and entering a filename. To quit 

HEIWEST choose "Quit" from the main menu.

To activate the main menu in HEIWEST, press the forward "/" key. The complete menu 

system is shown in figure 4. Select a menu choice by pressing the letter key 

corresponding to the first letter of each command. The user may exit a menu without 

selecting a command by pressing the "Esc" key. Selecting a command either causes a 

program action, displays a submenu, or prompts for user-supplied information. Prompts 

ending with a question mark generally expect a "yes" or "no" response (the lone 

exception is the "Options Forage Species" command). Pressing the "Y" key corresponds 

to a "yes" response; any other key corresponds to a "no" response. Prompts that end with 

three dots generally are status messages indicating an action that the program is 

currently executing; however, if such a prompt contains the message "Press any key," the 

program halts execution until the user completes the action requested and presses any 

key, thereby signaling the program to continue. Prompts ending with a colon expect the 

user to type an appropriate response. Some prompts will display a default response.

The "Map" command is used to load existing maps, save newly created or changed 

maps, print maps, and to clear the map display so that a new map can be created. All 

these operations are accessed on a submenu that appears after the "Maps" command is 

invoked, as explained below.

Loading maps-The "Load" command reads from an existing habitat maps file. If the 

specified file name is not found, the prompt for the file name is redisplayed for editing and 

re-entry. If the specified file name is found, the map display is cleared automatically, an 

open database will be closed, and the map is loaded into memory. Map files must 

conform to the standard ASCII convention, commonly referred to as "text files." The ASCII 

convention calls for an end-of-line sequence (ASCII code 13 followed by ASCII code 10) 

at the end of each line. In addition, an end-of-file marker (ASCII code 26) must exist at 

the end of the file. If standard text editors are used to create maps, or the maps are 

generated with the procedures outlined later in this paper, the map files conform to the 

ASCII convention. If maps are created with word

The HEIWEST

Command Menu

Loading, Viewing,

Editing, and Printing

Maps

6
processors, they must be saved as "text files." When maps are loaded, every 

character on the line is read, but only the characters corresponding to known habitat 

codes (see table 1) will appear in the map. Characters and numbers not used by 

HEIWEST (all other numbers and letters in the alphabet) become blanks in the map. If 

characters with ASCII codes of less than 32 appear in the map (special characters 

and symbols), they are ignored during the load process, thereby compacting map 

rows and possibly realigning columns. Any map lines containing more characters than 

the maximum number of map array columns (600) are truncated. Any map file lines 

exceeding the maximum number of map array rows are ignored.

7
Viewing maps-Once a map is loaded, it can be viewed and edited. The location of the 

highlighted cursor can be changed, within the limits of the map array, by several means. 

The four arrow keys move the cursor to adjacent pixels. The "PgUp" and "PgDn" keys 

display the next screen portion of the map above and below the current display. Holding the 

"Ctrl" key down and pressing the right or left arrow displays the next screen portion of the 

map to the right or left of the current display. Pressing the "Home" key moves the cursor to 

the upper left corner of the map array, and pressing the "End" key moves the cursor to the 

bottom right corner of the map. The latter corner is the intersection of the last column and 

last row containing a habitat code; it is not necessarily equivalent to the bottom right corner 

of the map array.

Editing maps -Habitat codes contained in the map can be added, changed, or deleted during 

a viewing session. Pressing any of the keys corresponding to valid habitat codes (table 1) 

accordingly replaces the contents of the pixel highlighted by the cursor. It also is possible to 

change habitat codes with a mouse; pressing the left mouse key replaces the pixel contents 

with the last habitat code typed from the keyboard. Blank pixels can be added to the 

analysis area by this method, and the contents of any highlighted pixel can be erased by 

pressing the "Del" key, thereby placing that pixel outside the analysis area.

Saving maps-Maps are saved by using the "Save" command. Maps also can be saved 

whenever the "Load", "Clear", and "Quit" commands are activated, which automatically 

prompt the user to save any changes made since the map was last saved.

Printing maps-The "Print" command sends the current map to an attached printer. The 

map is printed on numbered pages containing 128 columns and 56 rows with map 

coordinates in the margins. The printer must be capable of printing 132 characters per line 

and 60 lines per page. Printers that use letter-size paper must be set for compressed print 

mode. The user will be prompted to press any key when the printer is on-line and ready to 

receive the map. A bell rings to alert the user if printing problems occur.

Clearing the viewing screen-The "Clear" command clears the map array. Once the array 

is cleared, a new map can be created by entering habitat codes directly. It is not necessary 

to "Clear" before loading a new map file. If changes have been made to the current map, the 

user is prompted to save the current map and the save process is called. "Clear" also will 

close an open database.

The "Options" command changes default parameters associated with open road miles, map 

pixel size, and display attributes. Changes made to default parameters are not saved and 

must be specified anew with each HEIWEST session. Selecting the "Options" command 

leads to a submenu of the default parameters, as described below.

Open road mileage -Selecting the "Roads" command prompts the user to input the number 

of miles of road open to vehicular traffic within the map analysis area. The default is zero, 

but valid input ranges from zero to 9999.9 miles. Any valid entry will change the current 

number of road miles.

Map pixel size-Selecting the "Pixels" command prompts the user to input the number of 

feet per side of the map pixels. The default is 150 feet, but valid input ranges from 66 to 300 

feet. Entering zero feet returns to the map display without changing the current pixel size.

Changing Defaults for 

Roads, Pixel Size, and 

Display

8
Display attributes-If an EGA or VGA graphics adapter is installed, the "Toggle" command 

will appear on the "Options" menu. This option switches the display to 43 (EGA) or 50 

(VGA) lines from the standard 25 lines.

The "Run" command calculates HEI from the cover map and its associated parameters. A 

bell rings when the calculations are complete. The results are displayed along with a prompt 

to print the results. The map display returns to the screen when the printing process is 

completed.

HEIWEST has a database feature that allows databases to be linked to habitat maps. The 

"Database" command is used to access an ASCII database file associated with the current 

map. Each record of the database corresponds to a pixel address and has five 10-character 

fields containing attributes pertaining to the pixel. Once a database has been linked to the 

current map, the user can display the attributes of the pixel covered by the highlighted 

cursor. This feature is useful for associating attributes such as stand identification numbers 

with the current map. The user can also use the database features to generate a database 

of attribute data for all treated pixels, which can be useful for summarizing the treatment 

effects in terms of map attributes. The timber volumes of treated pixels could be summed, 

for example, to produce an estimate of the harvest volume associated with a particular HEI.

Databases to link with HEIWEST must be an ASCII file sorted in order of row (y-coordinate) 

within column (x-coordinate). The file must end with an end-of-file marker (^Z or ASCII code 

26). Each line (record) in the database file must begin with the number 8 and finish with an 

end-of-line sequence (ASCII codes 13 and 10). In addition, each line must have 56 

characters between the number 8 and the end-of-line sequence. The first six characters are 

the pixel address with which to associate the attribute data: they are followed by five 

10-character attribute fields. All attribute fields must exist regardless of usage. Unused 

fields should be filled with spaces, if there are no data available. Many types of software, 

such as database managers, word processors and spreadsheets, can be used to create 

and maintain a database. But the structure and sorting requirements must be met for the 

HEIWEST software to properly access the associated data.

Calculating HEI and

Printing the Results

Using the Database

Feature of HEIWEST

9
Linking a database -Databases are linked to a habitat map by using the "Link" command. If 

a map is currently displayed, selecting the "Link" command prompts the user to specify the 

name of the database file to link. Any database currently linked to the map closes 

automatically before linking the newly specified database. The message "F2 Shows 

Attributes" is displayed on the status line whenever a database is linked to the current map. 

Pressing "F2" causes the linked database to be searched for a record corresponding to the 

address of the pixel covered by the highlighted cursor. If such a record is located, the record 

attributes are displayed on the status line. Otherwise, the message "Attribute Data Not 

Found" is displayed. Press any key to clear the status line and return to the current map 

when finished viewing the displayed attributes.

To demonstrate the database linking procedure, the WEST.DB file on the distribution 

diskette can be linked to WEST.MAP by using the above procedures. Next, position the 

cursor on any pixel in the map, and press the "F2" key. Attributes from the database are 

displayed along the bottom of the screen.

Unlinking databases-Databases are unlinked and closed with the "Unlink" command.

Spooling databases-The spooling feature provides a method of reporting the database 

attributes for all pixels that have had habitat codes changed to one of the treatment codes 

(habitat codes "3", "4", or "5"). The user is first prompted to specify the name of the database 

file to which records are spooled. Entering no file name does not spool the database and 

instead returns the program to the map display. At the completion of the file spool process, 

the program returns to the map display.

The spooling feature can be demonstrated with the WEST.DB file on the distribution map. 

After loading WEST.MAP and linking WEST.DB, change some of the habitat codes to "4", 

thereby signifying a clearcut. Invoke the "Spool" command and enter a filename. Exit the 

program, and view the spooled data with B.COM program (provided on the distribution 

diskette) by typing "B filename", where filename is the name given to the spooled data. 

These data then can be imported to a database to describe affected resources.

HEIWEST is terminated with the "Quit" command. If changes have been made to the current 

map since it was last saved, "Quit" prompts the user to save the current map.

There are several ways to obtain cover maps for HEIWEST. In all methods, the starting point 

is a cover map showing polygons of the basic habitat types. The simplest method for 

converting these maps into a text file of cover codes is to overlay a Mylar grid constructed so 

that each pixel corresponds to the selected pixel size (for example 50 by 50 yards, or 0.517 

acre) on the cover map, and code the value of each pixel directly on the Mylar. The codes 

are typed directly into an ASCII file with any editor. Mylar grids can be generated with CAD 

software.

With GIS software, such as MOSS-MAPS, cover maps can be digitized, rasterized 

(converted to a pixel map), and exported. In MOSS, vector maps are converted to raster 

format with the "Polycell" command. Maps should be polycelled to a pixel size of 25, 50, or 

100 yards on a side. Our testing indicates that a pixel size of 50 by 50 yards (0.517 acre) 

produces good resolution and minimizes errors in the raster process. When prompted by 

MOSS in the polycell process, enter 0.517 acre, with a pixel ratio of 1. The map type is 

"Discrete", "Type 7", and pixels are assigned by "Subject Number" (option 5).

Quitting the Program

Obtaining Habitat

Maps for HEIWEST

10
Exporting the map is most easily accomplished with the MOSS-MAPS "SPSS" command, 

which produces an ASCII data file containing row, column, and map subjects. This same 

technique can be used to generate databases to link with habitat maps. When prompted in 

the SPSS procedure whether to eliminate empty cases, choose "yes". After downloading to 

the microcomputer, this file is processed with HEIUTIL.EXE program distributed with 

HEIWEST to regenerate the map. The polycelled map should be examined to ensure that 

MOSS assigned values to map subjects according to the format required by HEIWEST 

(see table 1). To determine if the map requires recoding, examine the raster map subjects 

by using the "Describe" command. If subjects are incorrectly coded, they can be recoded 

within the HEIUTIL

program.

HEIWEST can process maps having pixels between 0.1 and 2.066 acres. The maximum 

size of 2.066 acres is determined by the distance bands in the HEI model being in 

increments of 100 yards, and a 100-yard-square pixel is 2.066 acres. For HEIWEST to 

function as intended, pixels should have dimensions of either 25, 50, or 100 yards on a 

side, which corresponds to 0.129, 0.517, and 2.066 acres, respectively. Our tests with 

cover maps of winter range in the Blue Mountains showed that a pixel size of 0.517 acre is 

the most efficient scale. Larger pixel sizes (for example 2,066 acres) resulted in a loss of 

small "stringers" of cover during the polycell process in MOSS-MAPS. These small cover 

areas may not be significant in terms of habitat use by elk (see Thomas and others 1988), 

but we believe their deletion from the habitat map should be performed by wildlife biologists 

rather than by GIS software. In addition, with 100- by 100-yard pixels, the diagonal 

distance between pixels centers is 141.42 yards, and thus habitat comparisons between 

diagonal pixels contribute to the 101- to 200-yard spacing band. These problems are 

largely nonexistent with pixel sizes of 0.517 or 0.129 acre. The only problem with using a 

smaller pixel size is that map arrays become somewhat large and processing time is 

increased.

HEIWEST can also be used to calculate indices of edge-to-area and forest fragmentation 

(Harris 1984). For example, suppose it is desired to estimate the acreage of "interior" late 

seral stage habitat. For this example, "interior" will be defined as late seral habitat that is at 

least 100 yards from the edge between the later and all other seral stages. The first step is 

to prepare a habitat map, as described earlier, and code the late seral stage habitat as a 

"2" or "3" in the map. Code all other habitat as "1". In this way, late seral habitat is 

represented as cover, and other seral stages as forage. The map is processed with 

HEIWEST, which will output the area in each of the 100-yard distance bands into the late 

seral stage habitat. In this example, "interior" habitat would be calculated as the sum of the 

area in all the distance bands except the 0-100 yards. This general method can be applied 

to data describing virtually any habitat feature (for example, acres of habitat that are at 

least 100 yards from a road).

It also is possible to calculate another index of fragmentation, the edge-to-area ratio 

(Thomas and others 1979). The total edge length of the habitat coded as cover ("1" and 

"2") in the habitat map is output to the screen along with the total area. The edge-to-area 

ratio is calculated as the edge length divided by the total area.

Partial funding for this project was provided by the Blue Mountains Elk Initiative. Valuable 

comments to this manuscript were provided by Mike Wisdom and Bill Krantz.

11

Optimal Pixel Size 

for Habitat Maps

Using HEIWEST to 

Calculate 

Fragmentation

Acknowledgments
Harris, L.D. 1984. The fragmented forest. Chicago: University of Chicago Press. 211 p.

Hitchcock, Mark; Ager, Alan. [In press]. Microcomputer software for calculating elk habitat 

effectiveness index on Blue Mountain winter ranges. Gen. Tech. Rep. PNW-GTR-301. 

Portland, OR: U.S. Department of Agriculture, Forest Servi ce, Pacific Northwest Research 

Station.

Lyon, J. 1983. Road density models describing habitat effectiveness for elk. Journal of 

Forestry 81: 592-595.

Thomas, Jack Ward; Black, Hugh, Jr.; Scherzinger, Richard J.; Pedersen, R.J. 1979. Deer 

and elk. In: Thomas, Jack Ward, tech. ed. Wildlife habitats in managed forests-the Blue 

Mountains of Oregon and Washington. Agric. Handb. 553. Washington, DC; U.S. 

Department of Agriculture: 104-127.

Thomas, J.W.; Leckenby, D.A.; Henjum, M. [and others]. 1988. Habitat effectiveness index 

for elk on Blue Mountain winter ranges. Gen. Tech. Rep. PNW-GTR-218. Portland, OR; 

U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 28 p.

Wisdom, M.J.; Bright, L.R.; Carey, C.G. [and others]. 1986. A model to evaluate elk habitat 

in western Oregon. R6-F&WL-216-1986. Portland, OR; U.S. Department of Agriculture, 

Forest Service, Pacific Northwest Region. 36 p.

Literature Cited

 U.S. GOVERNMENT PRINTING OFFICE: 

1992-695-597!63,008 REGION NO. 10

12
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Agriculture is dedicated to the principle of multiple use 

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recreation. Through forestry research, cooperation with 

the States and private forest owners, and management 

of the National Forests and National Grasslands, it 

strives–as directed by Congress–to provide 

increasingly greater service to a growing Nation.

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Opportunity Employer. Applicants for all Department 

programs will be given equal consideration without 

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origin.

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Avenue P.O. Box 3890 Portland, Oregon 97208-3890