GEOLOGICAL SURVEY CIRCULAR 671 

A Land-Use Classification 

System for Use With 

Remote Sensor Data 

By James R. Anderson, Ernest E. Hardy, and 

John T. Roach 

GEOLOGICAL SURVEY CIRCULAR 671 

For the Inter-Agency Steering CommiHee on 

Land Use Information and Classification 

Washington 1972 
United States Department of the Interior 

ROGERS C. B. MORTON, Secretary 

Geological Survey 

V. E. McKelvey, Director 

Free on application to the U.S. Geological Survey, Washington, D.C. 20242 
CONTENTS 

Page 

Abstract 1 

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 

The need for standardization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 

Designing a land-use classification system for use with remote-sensing techniques 2 

Development of the classification system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 

Land-use classification system for use with remote-sensor data . . . . . . . . . . . . . . . . . . 6 

Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 

Urban and built-up land . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 

Agricultural land ................................................. 10 

Rangeland . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 

Forest land ................. ·. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 

Water .......................................................... 12 

Nonforested wetland .............................................. 13 

Barren land . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 

Tundra ........................................................ 15 

Permanent snow and icefields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 

Selected references . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 

III 

A Land-Use Classification System for Use 

With Remote-Sensor Data 

By James R. Anderson, Ernest E. Hardy, and John T. Roach 

for the 

Inter-Agency Steering Committee on land Use Information 

and Classification 

ABSTRACT 

The framework of a national land-use classification 

system is proposed for testing and review. The 

classification has been developed to meet the needs of 

Federal and State agencies for an up-to-date overview of 

land use throughout the country on a basis that is 

uniform in date, scale, and categorization at the more 

generalized first and second levels and that will be 

receptive to data from instrumented satellite and 

high-altitude aircraft platforms. The classification system 

utilizes the best features of existing widely used 

classification systems to the extent that they are 

amenable to use with remote-sensing, and it is 

open-ended so that regional, state, and local agencies 

may develop more detailed land-use classification 

systems, at third and fourth levels, to meet their 

particular needs and at the same time remain compatible 

with each other and with the national system. 

Introduction 

A modern nation, as a modern business, 

must have adequate information on many 

complexly interrelated aspects of its activities in 

order to make decisions. Land use is only one 

such aspect, but it is one that has become 

increasingly important as the nation seeks to 

grapple with the problems of slum clearance and 

urban renewal, and of suburban expansion, 

highway planning, and transportation systems. 

Land use can also serve as an effective surrogate 

in the analysis of environmental processes and 

1 

problems that must be better understood if 

living conditions are to be enhanced. 

The Need for Standardization 

For many years, agencies at various 

governmental levels have been collecting data 

about land, but for the most part they have 

worked independently and without 

coordination. Too often this has meant 

duplication of effort, or it has been found that 

data collected for a specific purpose were of 

little or no value for a similar purpose only a 

short time later. 

Remote-sensing techniques, including 

conventional aerial photography, can now be 

used effectively to complement surveys based on 

ground observation and enumeration, so we have 

the potential of a timely and accurate inventory 

of the current use of the nation's land resources. 

At the same time, data processing techniques 

permit the storage of large quantities of detailed 

information that can be organized in a variety of 

ways to meet specific needs. 

As the result of long concern about 

duplication and coordination among Federal, 

State, and local governments in the collection 

and handling of different types of data, we have 

already in some instances achieved reasonably 
effective, though not perfect, solutions, as 

evidenced by present programs in soil surveys, 

topographic mapping, collection of weather 

information, and the inventory of forest 

resources. The recent developments in 

data-processing and remote-sensing technology 

make the need for similar cooperation in 

land-use inventories that much more evident and 

more pressing. Development and acceptance of a 

system for classifying land-use information, 

obtained primarily by use of remote-sensing 

techniques but reasonably compatible with 

existing classification systems, is the urgently 

needed first step. 

Designing a Land-Use Classification System for Use With Remote-Sensing 

Techniques 

There is no ideal classification of land use, 

and it is unlikely that one will ever be 

developed. There are different perspectives in 

the classification process, and the process itself 

tends to be subjective even when an objective 

numerical approach is used. There is, in fact, no 

logical reason to expect that one detailed 

inventory will be adequate for more than a 

relatively short period of time. Land-use 

patterns change, as do our demands for the 

natural resources which affect the development 

of land-use patterns. Each land-use classification 

is made to suit the needs of the user, and few 

users will be satisfied with an inventory that 

does not meet most of their needs. In 

attempting to develop a classification system for 

use with remote-sensing techniques that will 

satisfy the needs of the majority of users, certain 

guidelines of criteria for evaluation must first be 

established. 

To begin with, there is considerable diversity 

of opinion about what constitutes "land use," 

although present use of land is one of the 

characteristics that is widely recognized as 

significant for planning and management 

purposes. One concept that has much merit is 

that land use refers to "man's activities on land 

which are directly related to the land" (Clawson 

and Stewart, 1965). Land cover, on the other 

hand, would describe "the vegetational and 

2 

artificial constructions covering the land 

surface" (Burley, 1961). 

Some activities of man can be directly 

related to the type of land cover. The presence 

of planted corn most probably indicates that 

farming is the land-using activity on that 

particular tract. Thus, from imagery on which 

corn can be identified as the land cover, it may 

be reliably inferred that farming, which may not 

be actually visible, is the present activity. Other 

activities, especially recreational activities, can 

be related to land cover by use of remote-sensing 

techniques only with difficulty. Hunting is a 

common recreational use, but most hunting is 

done on land that is better classified as forest, 

range, or agricultural land, and complementary 

techniques will be needed to identify hunting as 

a land-using activity. Land cover is therefore the 

basis for categorization at the first and second 

levels, and the activity dimension of land use 

will appear at third and fourth levels of 

categorization. 

In almost any classification process, it is rare 

to find the clearly defined classes that we would 

like. In determining land cover, it would seem 

simple to draw the line between land and water, 

until one considers the problems of seasonally 

wet areas, tidal flats, or marshes with various 

kinds of plant cover. Most types of land use 

appear in a continuous gradation from zero, or 

no use, to 100, or full use. The problem to be 

solved is where to place the boundary around 

the use we wish to classify. How small an area of 

land with discarded equipment on it should be 

called a junkyard? How large an area should be 

in any particular use before we recognize the 

use? How do we resolve the problem of 

heterogeneous mixtures of equally significant 

land uses? Or of multiple uses of an area? 

Decisions that may seem arbitrary at times must 

be made, but if the descriptions of categories are 

complete and guidelines are explained, the 

inventory process can be repeated. The 

classification system must allow for the 

classification of all parts of the area under study 

and should also provide a unit of reference for 

each land use. 
A land-use classification system for use with 

orbital imagery should meet the following 

criteria (Anderson, 1971): 

1. The minimum level of accuracy in the 

interpretation of the imagery should be about 

90 percent. 

2. The accuracy of interpretation for the 

several categories should be about equal. 

3. Repeatable or repetitive results should be 

obtainable from one interpreter to another and 

from one time of sensing to another. 

4. The classification system should be 

usable or adaptable for use over an extensive 

area. 

5. The categorization should permit 

vegetation and other types of land cover to be 

used as surrogates for activity. 

6. The classification system should be 

suitable for use with imagery taken at different 

times of the year. 

7. Effective use of sub-categories that can 

be obtained from ground surveys or from the 

use of larger-scale or enhanced imagery should 

be possible. 

8. Collapse of categories must be possible. 

9. Comparison with land-use information 

compiled in the past or to be collected in the 

future should be possible. 

10. Multiple-use aspects of land use should 

be recognized when possible. 

It is hoped that in the use of this proposed 

land-use classification system, which involves 

only Levels I and II, an accuracy in 

interpretation can be attained that will make the 

land-use information comparable in quality to 

that obtained in other ways. For many users of 

land-use information, the accuracy of 

interpretation at the generalized first and second 

levels is satisfactory when the interpreter makes 

the correct interpretation 85 to 90 percent of 

the time. Greater accuracy will generally be 

attained only at much higher costs, which may 

not be justified for the purposes for which the 

information is obtained. 

The accuracy ultimately attainable at each 

level of the classification system will in large 

part be determined by the capabilities of the 

sensors. At present, we are quite well apprised of 

the capabilities of aerial photographs at scales of 

3 

1:50,000 to 1:20,000 or larger. We have limited 

experience with imagery at scales between 

1:50,000 and 1:120,000 and essentially no 

experience to draw on with imagery at ratios of 

less than 1:200,000. Experience in learning how 

to extract information from the commonly used 

1 : 2 0 , 0 0 0 imagery, however, indicates that 

whatever our present ability may be, it will 

improve. 

There have been a few major and dramatic 

developments in automatic and semiautomatic 

equipment for interpretation, but for the most 

part, these are still experimental and there is 

very little expertise in their use. Thus 

classification of land use from imagery will 

remain a personal task for an indefinite period 

of time and will only gradually become a 

semiautomatic process and perhaps eventually a 

fully automatic procedure. For the time being, 

the problems of information retrieval are 

problems of visual interpretation. 

The kinds and amounts of land-use 

information that may be obtained from 

different sensors depend on the altitude or the 

resolution of each. There is little likelihood that 

any one sensor or system will produce good 

information at all altitudes. It would be 

desirable to evaluate each source of 

remote-sensing information and its application 

solely on the basis of the qualities and 

characteristics of the source. However, it is 

common practice to transfer the data to a base 

map, and no matter what our guidelines, it is 

difficult to use a base map without extracting 

some additional information. Topographic maps 

contain an abundance of information, and even 

road maps or a detailed city map will contribute 

detail beyond the capabilities of the 

remote-sensor image employed. 

The land-use classification system described 

in this report has been developed on the 

assumption that different sensors will provide 

information for different levels of classification. 

In general, the following relations are 

anticipated: 

Classification Level 

I ............ . 

Source of information 

Satellite imagery, with very little 

supplemental information. 
Classification Level-con. Source of Information-con. 

II . . . . . . . . . . . . . High -a I t it u de a n d sate II i te 

imagery combined with 

topographic maps. 

III . . . . . . . . . . . . Medium-altitude remote sensing 

( 1 : 2 0, 000) combined with 

detailed topographic maps 

and substantial amounts of 

supplemental information. 

IV . . . . . . . . . . . . Low-altitude imagery with most 

of the information derived 

from supplemental sources. 

Satellite imagery from ERTS-A and ERTS-B 

will generally be prepared for users at a ratio of 

1:1,000,000. At this ratio, 1 centimeter 

represents 10 kilometers or 1 inch equals about 

16 miles. Even if information is generated by 

transferring data to much larger scale maps, only 

a general classification, based on major 

differences in land cover, can be made. This 

would also be true for imagery at ratios up to 

1:250,000, and Level I would be appropriate for 

these sources also. 

Second-level units of classification are based 

on retrieval from imagery at a ratio of about 

1:100,000. At this ratio, 1 centimeter represents 

1 kilometer and 1 inch equals about 1.6 miles. 

Information can be transferred with reasonable 

accuracy to fairly detailed maps, even to the 

U.S. Geological Survey 1:24,000 topographic 

maps, and a substantial amount of supplemental 

input can be obtained. The greater detail will 

allow classification on the basis of more specific 

uses of land rather than only nine major types of 

cover, and the complexity of the inventory can 

be increased. 

The categories proposed at Level II cannot 

all be interpreted with equal reliability. In parts 

of the United States, some may be extremely 

difficult to interpret from high-altitude aircraft 

imagery alone. Rather than mutilate the 

categorization or distort it and so reduce the 

number of useful applications, it seems 

preferable to suggest that additional steps be 

taken to obtain a satisfactory interpretation. 

Conventional aerial photography and sources of 

information other than remote sensor data may 

be needed for interpretation of especially 

difficult areas. On the basis of tests in the 

4 

Central Atlantic Regional Ecological Test Site, 

the Phoenix Pilot Project, and land-use mapping 

for the Ozark Regional Commission, we believe 

that the cost of using such supplementary 

information can be held to reasonable levels. 

At Level III, which is beyond the scope of 

the present discussion, we would look forward 

to using substantial amounts of supplemental 

information in addition to remotely sensed 

information at ratios of 1:40,000 to 1:15,000. 

At a typical ratio of 1:24,000, 1 inch represents 

2,000 feet, and information can be transferred 

directly to the 1:24,000 topographic maps. 

Surprisingly detailed inventories may be 

undertaken, and by using both remotely sensed 

and supplemental information, most land uses 

except those of the very complex urban areas or 

the thoroughly heterogeneous mixtures can 

adequately located, measured, and coded. 

Level IV of the projected classification 

would call for much more supplemental 

information and remotely-sensed data at a much 

larger scale. 

Development of the Classification System 

The needs of Federal agencies for a broad 

overview of national land-use patterns and 

trends and environmental values led to the 

formation in early 1971 of an Inter-Agency 

Steering Committee on Land Use Information 

and Classification. The work of the committee,· 

composed of representatives from the Geological 

Survey of the U.S. Department of the Interior, 

the National Aeronautics and Space 

Administration, the Soil Conservation Service of 

the U.S. Department of Agriculture, the 

Association of American Geographers, and the 

International Geographical Union, has been 

supported by NASA and the Department of the 

Interior and has been coordinated by the U.S. 

Geological Survey. 

One objective of the committee was the 

development of a national classification system 

that would be receptive to inputs of data from 

both conventional sources and remote sensors 

on high-altitude aircraft and satellite platforms, 
and that would at the same time form the 

framework into which the categories of more 

detailed land-use studies by regional, state, and 

local agencies could be fitted and aggregated 

upward for more generalized smaller-scale use at 

the national level. 

Several land-use classification systems 

designed for or amenable to use with 

remote-sensing techniques served as the basis for 

discussion at a Conference on Land Use 

Information and Classification in Washington, 

D.C., June 28-30, 1971, attended by more than 

150 representatives of Federal agencies, state 

and local governments, universities, institutes, 

and private concerns. On the basis of these 

discussions, the steering committee then 

proposed to develop and test a land-use 

classification system that could be used with 

remote sensing and minimal reliance on 

supplemental information at the more 

generalized first and second levels of 

categorization. The need for compatibility with 

the more generalized levels of land-use 

categorization in classification systems currently 

in use was clearly recognized, especially those of 

the Standard Land Use Coding Manual, the 

Inventory of Major ·Uses of Land and Water 

made every 5 years by the Economic Research 

Service of the U.S. De:partment of Agriculture, 

and the National Inventory of Soil and Water 

Conservation Needs, initiated in 1956 and 

carried out for the second time in 1966 by 

several agencies of the U.S. Departments of 

Agriculture and Interior. 

Two land-use classification systems initially 

proposed by James R. Anderson for conference 

use were designed to place major reliance on 

remote sensing, although supplementary sources 

of information were assumed to be available for 

the more elaborate of the two. The classification 

system for the New York State Land Use and 

Natural Resources Inventory, developed mainly 

at the Center for Aerial Photographic Studies at 

Cornell University, had been designed for use 

with aerial photography at the 1:24,000 scale, 

and although devised specifically for New York 

State, it was adaptable for use elsewhere. To 

take advantage of the N-2-w York experience, 

5 

Ernest E. Hardy and John T. Roach were invited 

to collaborate in preparing the definitional 

framework of the proposed classification. 

Definitions of land-use categories used in New 

York have been carefully reviewed in relation to 

the m ore varied and complex definitional 

framework needed for the entire United States 

and have been modified to make them 

applicable to the country as a whole. Attention 

was given mainly to the more generalized first 

and second levels of categorization. Definitions 

for each of the categories on these two levels 

were subjected to selective testing and 

evaluation by the Geological Survey, using 

imagery obtained primarily from high-altitude 

flights as part of the research in connection with 

the Central Atlantic Regional Ecological Test 

Site, the Phoenix Pilot Project, and Land Use 

Mapping for the Ozark Regional Commission. 

The work of Lawrence R. Pettinger of the 

Forestry Remote Sensing Laboratory of the 

School of Forestry and Conservation at the 

University of California at Berkeley and 

Charles E. Poulton of Oregon State University 

on ''The Application of High Altitude 

Photography for Vegetation Resource 

Inventories in Southeastern Arizona" under 

contract with the National Aeronautics and 

Space Administration, which was being 

conducted at the same time as our development 

and testing program, provided valuable insights 

into the land use mosaic of the Southwestern 

United States. The hierarchical classification of 

barren lands and natural vegetation (rangeland) 

for that part of the United States is a significant 

contribution to the development of a land-use 

classification system and procedures amenable 

to use with remote-sensing techniques. Some of 

the definitional structure for barren land and 

rangeland suggested by Pettinger and Poulton 

has been adopted in this land-use classification 

system being proposed for general use 

throughout the United States. 

In developing the land-use classification 

system, we have made an effort to provide 

compatibility with the classification systems 

currently used by the several Federal agencies 

making land-use inventories. However, when 
complete or nearly complete reliance is placed 

on remote sensing as an inventory technique, it 

is not possible to obtain complete compatability 

with the categorization of land use employed 

with enumeration and observation techniques. 

Considerable care should be exercised in 

comparing land-use classifications based on data 

obtained by remote sensing and the definitions 

proposed in this report with classifications based 

on data obtained by enumeration and 

observation and category definitions written for 

use with those techniques. The definitions given 

in the concluding section of this report must be 

studied carefully before analyzing land-use 

information that has been classified in accord 

with the proposed classification system. 

As further advances in technology are made, 

it may be necessary to modify the classification 

system for use with automatic data analysis. The 

ER TS-A and Sky lab missions and the 

high-altitude aircraft program of the National 

Aeronautics and Space Administration offer an 

excellent opportunity for nationwide testing of 

the feasibility of using this classification system 

to obtain land-use information on a uniform 

basis. 

In summary, the land-use classification 

system being presented in this report includes 

only the more generalized first and second levels 

of classification. The definitional structure is a 

first approximation, capable of further 

refinement on the basis of more extended and 

varied use. We believe, however, that it meets 

the principal immediate objective of providing a 

land-use classification system for use with major 

research activities in the testing of 

remote-sensing techniques, and that it will be 

possible to use this proposed system with 

large-scale imagery as well as with other methods 

of collecting land-use data such as direct 

enumeration and observation. Attainment of the 

more fundamental and long-range objective of 

providing a standardized system of land-use 

classification for national and regional studies 

will depend on the effective revision and 

improvement that should result from widespread 

review and use of the system. Because it is 

impractical to circulate unpublished manuscripts 

widely, this manuscript is being submitted for 

6 

review and testing in the form of a U.S. 

Geological Survey circular. 

land-Use Classification System for Use 

With Remote Sensor Data 

Level I Level II 

01. Urban and Built-up Land. 

02. Agricultural Land. 

03. Rangeland. 

04. Forest Land. 

05. Water. 

06. Nonforested Wetland. 

07. Barren Land. 

08. Tundra. 

01. Residential. 

02. Commercial and services. 

03. Industrial. 

04. Extractive. 

05. Transportation, Communications, and 

Utilities. 

06. Institutional. 

07. Strip and Clustered 

Settlement. 

08. Mixed. 

09. Open and Other. 

01. Cropland and Pasture. 

02. Orchards, Groves, 

Bush Fruits, 

Vineyards, and 

Horticultural 

Areas. 

03. Feeding Operations. 

04. Other. 

01. Grass. 

02. Savannas (Palmetto 

Prairies). 

03. Chaparral. 

04. Desert Shrub. 

01. Deciduous. 

02. Evergreen (Coniferous 

and Other). 

03. Mixed. 

01. Streams and Waterways. 

02. Lakes. 

03. Reservoirs. 

04. Bays and Estuaries. 

05. Other. 

01. Vegetated. 

02. Bare. 

01. Salt Flats. 

02. Beaches. 

03. Sand Other Than 

Beaches. 

04. Bare Exposed Rock. 

05. Other. 

01. Tundra. 

09. Permanent Snow and Icefields. 

01. Permanent Snow and 

Ice fields. 
DEFINITIONS 

In the definitions presented here, an attempt 

has been made to include sufficient detail to 

provide a general understanding of what is 

included in each category at Levels I and II. 

Many of the uses described in detail will not be 

visible on spacecraft and high-altitude imagery. 

However, the detail will aid in the interpretation 

process, and the additional information will be 

useful to those who have large-scale aerial 

photographs and other supplemental 

information available. 

01. Urban and Built-Up land 

Urban and Built-up Land comprises areas of 

intensive use with much of the land covered by 

structures. Included in this category are cities, 

towns, villages, strip developments along 

highways, transportation, power, and 

communications facilities, and such isolated 

units as mills, mines, and quarries, shopping 

centers, and institutions. 

As development progresses, small blocks of 

land of less intensive or nonconforming use may 

be isolated in the midst of built-up areas and will 

generally be included in the 01-category. 

Agricultural, forest, or water areas on the fringe 

of Urban and Built-up areas will not be included 

except where they are part of low-density urban 

development. The Urban and Built-up Land 

category takes precedence over others when the 

criteria for more than one category are met. 

Thus, residential areas that have sufficient tree 

cover to meet Forest Land criteria will be placed 

in the Residential category. 

The Level II categories of Urban and 

Built-up Land are: Residential; Commercial and 

Services; Industrial; Extractive; Transportation, 

Communications, and Utilities; Institutions; 

Strip and Clustered Settlements; Mixed; and 

Open and Other. 

01-01. RESIDENTIAL 

Residential land uses range from high 

density, represented by the multiple-unit 

7 

structures of urban cores, to low density, where 

houses are on lots of more than an acre, on the 

periphery of urban expansion. Linear residential 

developments along transportation routes 

extending outward from urban areas should be 

included as residential appendages to urban 

centers, but care must be taken to distinguish 

them from commercial strips in the same 

locality. The residential strips generally have a 

uniform size and spacing of structures, linear 

driveways, and lawn areas; the commercial strips 

are more likely to have buildings of different 

sizes and spacing, large driveways, and parking 

areas. Residential development along shorelines 

is also linear and sometimes extends back only 

one residential parcel from the shoreline to the 

first road. 

Areas of sparse residential land use will be 

included under another category. In some 

places, the boundary will be clear where new 

housing developments abut against intensively 

used agricultural areas, but the boundary may be 

vague and difficult to discen1 when residential 

development is sporadiC, or occurs in small 

isolated units over an extended period of time in 

areas of mixed or less intensive uses. A careful 

evaluation of density and the overall relation of 

the area to the total urban complex must be 

made. 

Residential sections may also be included in 

other use categories where they are integral parts 

of the other use. Housing on military bases, at 

colleges and universities, living quarters for 

laborers near a work base, or lodging for 

employees of agricultural field operations or 

resorts are often difficult to identify and may be 

placed within the institutional, industrial, 

agricultural, or commercial categories. 

0 1-02. COMMERCIAL AND SERVICES 

Commercial areas are those used 

predominantly for the sale of products and 

services. They are often abutted by residential, 

agricultural, or other contrasting uses which help 

define them. The principal components of the 

Commercial-use category are urban central 

business districts; shopping centers, usually in 
suburban and outlying areas; commercial strip 

developments along major highways and access 

routes to cities; and resorts. The main buildings, 

secondary structures, and areas supporting the 

basic use are all included-office buildings, 

warehouses, driveways, sheds, parking lots, 

landscaped areas, and waste-disposal areas. 

Commercial areas may include some 

noncommercial uses too small to be separated 

out. Central business districts often include 

some institutions, such as churches and schools, 

and commercial strip developments may include 

some residential units. These are not separated 

out unless they exceed one-third the total 

commercial area. Recreational areas are not 

segre~ated. as such at Level II but may cause 

some problems in identification. Recreational 

facilities that form an integral part of an 

institution should be included in the 

Institutional category. A self-contained sports 

area, on the other hand, such as a stadium for 

professional events, is Commercial. There is 

usually a major visible difference in the form of 

parking facilities, arrangements for traffic flow, 

and the general association of buildings and 

facilities. Near a resort, the intensively 

developed recreational areas would be included 

in the Commercial category, but extensive golf 

courses and riding areas would be included in 

another category, the Open and Other, if in an 

urban setting. Public and private golf courses, ski 

and toboggan areas, and other recreational 

facilities are also classed as Open land. 

01-03. INDUSTRIAL 

Industrial areas include a wide array of uses 

from light manufacturing and industrial parks to 

heavy manufacturing plants. Identification of 

light industries-those focused on design, 

assembly, finishing, and packaging of 

products-can often be based on the type of 

building, parking, and shipping arrangements. 

Light industrial areas may be, but are not 

necessarily, directly in contact with urban areas; 

many are now found at airports or in relatively 

open country. Heavy industries use raw 

materials such as iron ore, lumber, or coal. 

Included are steel mills, pulp or lumber mills, 

electric power generating stations, oil refineries 

8 

and tank farms, chemical plants and 

brick-making plants. Stock piles of raw 

materials, large power sources, and waste 

product disposal areas are usually visible, along 

with transportation facilities capable of handling 

heavy materials. 

01-04. EXTRACTIVE 

Extractive Land encompasses both surface 

and subsurface mining operations, such as sand 

and gravel pits, stone quarries, oil and gas wells, 

and metallic and nonmetallic mines. In size, 

these activities range from the unmistakable 

giant strip or pit mines covering vast areas to the 

unidentifiable gas wells less than a foot square. 

Surface structures and equipment may range 

from a minimum of a loading device and trucks 

to extended areas with access roads, processing 

facilities, stockpiles, equipment sheds, and 

numerous vehicles. Spoil material and slag heaps 

are usually found within a short trucking 

distance of the major mine areas and may be the 

key indicator of underground mining operations. 

Uniform identification of all these diverse 

extractive uses is extremely difficult from 

remote sensor data alone. 

Industrial complexes where the extracted 

material is refined, packaged, or further 

processed are included in the Industrial category 

even if the plant is adjacent to the mine. Areas 

of future reserves are included in the appropriate 

present-use category, Agricultural or Forest 

Land, regardless of the expected future use. 

Unused pits or quarries that have been flooded 

are placed in the Water category if the water 

body is larger than 40 acres. Areas of tailings, 

abandoned pits and quarries, and strip-mined 

areas may remain barren for decades unless steps 

are taken to hasten the establishment of 

vegetation. Until vegetative cover is established, 

such parcels remain in the Extractive category. 

01-05. TRANSPORTATION, COMMUNICATIONS, AND UTILITIES 

Major transportation routes and areas greatly 

influence other land uses, and many land-use 

boundaries are outlined by them. The types and 

extent of transportation facilities in a locality 
determine the degree of access and affect both 

the present' and potential use of the area. 

Highways and railways are characterized by 

areas of activity connected in linear patterns. 

The highways include areas used for 

interchanges, limited access right-of-way, and 

service and terminal facilities. Rail facilities 

include stations, parking lots, roundhouses, 

repair and switching yards, and related areas, but 

overland track is not included unless six or more 

tracks are joined to give sufficient width for 

delineation at a scale of 1:250,000. Spur 

connections from an active line are included in 

the appropriate Indus trial or Extractive 

category. 

Airports, seaports, and major lakeports are 

isolated areas of high utilization, usually with no 

well defined intervening connections, although 

some water ports are connected by canals. 

Airport facilities include the runways, 

intervening land, terminals, service buildings, 

navigation aids, fuel storage, parking lots, and a 

limited buffer zone. The perimeter fence around 

airports usually makes a very sharp boundary 

that is visible on high-altitude imagery. Small 

airports, such as those on rotatable farm land, 

heliports, and land associated with seaplane 

bases are not included. Port areas include the 

docks, shipyards, drydocks, locks, and 

watercourse-control structures. 

Communications and utilities areas involved 

in transport of water, gas, oil, electricity, and 

areas used for airwave communications are also 

included in this category. Pumping stations, 

electric substations, and areas used for radio, 

radar, or television antennas are the major types. 

Small facilities, or those associated with an 

industrial, commercial, or extractive land use, 

are included within the larger category with 

which they are associated. Long-distance gas, oil, 

electric, telephone, water, or other transmission 

facilities rarely constitute the dominant use of 

land over which they pass. If these uses are 

dominant and meet the minimum width criteria, 

they may .. be identified as transportation uses. 

0 1-06. INSTITUTIONAL 

Education, religious, health, correctional, 

and military facilities are the main components 

9 

of this subcategory. All buildings, grounds, and 

parking lots that compose the facility are 

included within the institutional unit, but areas 

not specifically related to the purpose of the 

institution should be placed in the appropriate 

category. Auxiliary land uses, particularly 

residential, commercial and services, and other 

supporting land uses on a military base would be 

included in the Institutional subcategory, but 

agricultural areas not specifically associated with 

correctional, educational, or religious 

institutions are placed in the appropriate 

agricultural category. Small institutional units, 

as, for example, many churches and some 

secondary and elementary schools, will not meet 

the minimum area requirements and will be 

included within another category, usually 

Residential or Commercial. Historic forts may 

be confused with correctional institutions 

because of the similarity of buildings, but the 

historical sites have larger parking areas and 

often smaller landscaped or grass areas. 

01-07. STRIP AND CLUSTERED SETILEMENT 

The Strip and Clustered Settlement category 

includes developments along transportation 

routes and the smaller cities, towns, and built-up 

areas where separate land uses may not be 

distinguishable. Residential, commercial, 

industrial, institutional, and occasionally other 

land uses may be included. Farmsteads 

intermixed with strip or cluster settlements will 

be included within the built-up land, but other 

agricultural land uses should be excluded. 

01-08. MIXED 

This category is used for a mixture of 

second-level urban uses in larger cities (more 

than 50,000 inhabitants) where no one use 

predominates. In any category, as much as 

one-third intermixture of another use is allowed 

without changing the basic classification, but 

where the intermixture is greater, where several 

uses, though each is less than one-third, are 

included, or where individual second-level units 

may be too small to be separated although the 

aggregate of such uses may be large, the Mixed 

category is used. 
01-09. OPEN AND OTHER (URBAN) 

Open land consists of golf courses, some 

parks, ski areas, cemeteries, and undeveloped 

land within an urban setting. Open land may be 

in very intensive use but a use that does not 

require structures. Other land includes the small 

blocks of less intensive or nonconforming uses 

that become isolated. 

02. Agricultural Land 

Agricultural Land may be broadly defined as 

land used primarily for production of farm 

commodities. On high -altitude imagery, the 

chief indications of agricultural activity will be 

symmetrical patterns made on the landscape by 

use of mechanized equipment. However, pasture 

and other lands where such equipment is used 

infrequently may not show as well-defined 

shapes as other areas. 

Symmetrical patterns are also characteristic 

of Urban and Built-up Lands because of street 

layout and development by blocks. 

Distinguishing between Agricultural and Urban 

and Built-up Lands should ordinarily be possible 

on the basis of urban activity indicators and the 

associated concentration of population. The 

number of building complexes is smaller and the 

density of the road and highway network is 

much lower in Agricultural Lands than in Urban 

and Built-up Land. Some urban land uses, such 

as parks and large cemeteries, however, may be 

mistaken for Agricultural Land, especially when 

they occur on the periphery of the urban areas. 

The interface of Agricultural Land with 

other categories of land use may sometimes be a 

transition zone in which there is an intermixture 

of land uses at first and second levels of 

categorization. Where farming activities are 

limited by wetness, the exact boundary may 

also be difficult to locate, and Agricultural Land 

may grade into swamp Forest Land, 

Nonforested Wetland, or Water. 

The Level II categories of Agricultural Land 

are: Cropland and Pasture; Orchards, Groves, 

Vineyards, Bush Fruits, and Horticultural Areas; 

Feeding Operations; and Other. 

10 

02-01. CROPLAND AND PASTURE 

The several components of Cropland and 

Pasture now used for agricultural statistics 

include: Cropland harvested; cultivated summer 

fallow and idle cropland; land on which crop 

failure occurs; cropland in soil improvement 

grasses and legumes; cropland used only for 

pasture or pasture in rotation with crops; 

pasture on land more or less permanently used 

for that purpose. From imagery alone, it is 

generally not possible to make a distinction 

between Cropland and Pasture with a high 

degree of accuracy and uniformity, let alone a 

distinction among the various components of 

Cropland. Moreover, some of the categories 

listed represent the condition of the land at the 

end of the growing season, and will not apply 

exactly to imagery taken at other times of the 

year. They will, however, be a gu.ide to 

identification of Cropland and Pasture. 

Certain factors vary throughout the United 

States and this variability must also be 

recognized; field size depends on topography, 

soil types, sizes of farms, kinds of crops and 

pastures, capital investment, labor availability 

and other conditions. Irrigated land in the 

Western States is easily recognized in contrast to 

Rangeland, but in the Eastern States, irrigation 

by use of overhead sprinklers cannot always be 

detected from imagery unless distinctive circular 

patterns are created. Drainage or water control 

on land used for cropland and pasture may also 

create a recognizable pattern that may aid in 

identification of the land use. In areas of 

quick-growing crops a field may appear to be in 

nonagricultural use unless the temporary nature 

of the inactivity is recognized. 

02-02. ORCHARDS, GROVES, VINEYARDS, BUSH-FRUIT AND 

HORTICULTURAL AREAS 

Orchards, groves, vineyards, and bush-fruit 

areas produce the various fruit, nut, and berry 

crops. Horticultural areas include nurseries, 

floricultural areas, and seed-and-sod areas used 

perennially for that purpose. Many of these 

areas may be included in another category, 
generally Cropland and Pasture, when 

identification is made by use of satellite or 

high-altitude imagery alone. Identification may 

be aided by recognition of the combination of 

soil qualities and climatological factors needed 

for these operations: water bodies in close 

proximity to moderate the effects of short 

duration temperature fluctuations; site selection 

for air drainage on sloping land; deep, 

well-drained soils on slopes moderate enough to 

permit use of machinery. Isolated orchards of a 

few acres do not constitute commercial orchards 

large enough to identify on high-altitude 

imagery, and remnants of the few acres of fruit 

trees on the family farm are usually not 

recognizable and are therefore not included. 

02-03. FEEDING OPERATIONS 

Feeding Operations are large, specialized, 

livestock-production enterprises, chiefly beef 

cattle feedlots and large poultry farms, but also 

including large hog and fur-bearing animal farms. 

These operations have large animal populations 

restricted to relatively small areas. The result is a 

concentration of waste material that is an 

environmental concern. The waste-disposal 

problems justify a separate subcategory for these 

relatively small areas. Feeding Operations have a 

built-up appearance, chiefly composed of 

buildings, much fencing, access paths, and 

waste-disposal areas. Some are located near an 

urban area to take advantage of transportation 

facilities and proximity to processing plants. 

Feeding operations in conjunction with 

another farm enterprise are not included. Also 

excluded are shipping corrals and other 

temporary holding facilities. Game farms and 

zoos do not meet the animal-population 

densities to be placed in this subcategory. 

02-04. OTHER AGRICUlTURAl lAND 

Inactive agricultural land is an important 

component of this subcategory. Such land has 

no physical indication of present agricultural use 

and no natural cover, such as brush, which 

would curtail its ready use for agriculture. 

Farmsteads, including holding areas for 

11 

livestock, farm lanes and roads, ditches and 

canals, small farm ponds, and similar uses are 

generally quite small and often unrecognizable 

from high -altitude imagery so that these uses 

will generally be included with adjacent 

agricultural uses. 

03. Rangeland 

Rangeland may be defined as land where the 

potential natural vegetation is predominantly 

grasses, grasslike plants, forbs, or shrubs, where 

natural herbivory was an important influence in 

its precivilization state, and that is more suitable 

for management by ecological rather than 

agronomic principles. Some rangelands have 

been or may be seeded to introduced or 

domesticated plant species. Most of the 

rangelands in the United States are in the 

Western Range, the area to the west of an 

irregular north-south line that cuts through the 

Dakotas, Nebraska, Kansas, Oklahoma, and 

Texas. Rangelands are also found in the 

Southeastern States and Alaska. 

The Level II categories of Rangeland are: 

Grass, Savannas (Palmetto Prairies), Chaparral, 

and Desert Shrub. 

03-01 . GRASS 

This subcategory encompasses the tall grass 

(or true prairie), short grass, bunch grass or 

palouse grass, and desert grass regions. These 

grass regions generally represent a sequence of 

declining amounts of available moisture. Most of 

the tall grass region has been plowed for 

agriculture. The bulk of the remaining tall grass 

range is now in North Dakota, Nebraska, 

southern Kansas and Oklahoma, and the Texas 

Coastal Plain. Short grass rangeland occurs in a 

strip about 300 miles wide from the Texas 

Panhandle northward to the Dakotas where it 

widens to cover the western half of the Dakotas, 

the eastern three-fourths of Montana, and the 

eastern third of Wyoming. 

03-02. SAVANNAS (PAlMEITO PRAIRIES) 

The Palmetto Prairies in south-central 

Florida, north, west, and southwest of Lake 
Okeechobee consist mainly of dense medium tall 

grasses with scattered palms and shrubs. Many 

areas are now in improved pasture. 

03-03. CHAPARRAL 

This category includes California chaparral, 

the scrub oak or shinnery, and the mountain 

brush types. 

03-04. DESERT SHRUB 

Vegetation in this zone includes the creosote 

bush, sagebrush, greasewood, and other desert 

shrubs. Bottom lands and moister flats are often 

characterized by dense stands of mesquite, and 

where alkali is high, desert saltbrush dominates 

wide areas. 

04. Forest Land 

Forest lands are lands that are at least 10 

percent stocked by trees capable of producing 

timber or other wood products that exert an 

influence on the climate or water regime. Forest 

land can generally be identified rather easily 

from high-altitude imagery, although the 

boundary between it and other classes of land 

may be difficult to delineate precisely. 

Lands from which trees have been removed 

to less than 10 percent stocking but which have 

not been developed for other use are also 

included. For example, lands on which there is 

forest rotation, involving clear-cutting and block 

planting, are part of Forest Land. On such lands, 

when trees reach marketable size, which for 

pulpwood in the Southeastern United States 

may occur in two to three decades, there will be 

large areas that have little or no visible forest 

growth. The pattern can sometimes be identified 

by the presence of cutting operations in the 

midst of a large expanse of forest. Unless there is 

evidence of other use, such areas of little or no 

forest growth should be included in the Forest 

Land category. Lands that meet the 

requirements for Forest Land and also for a 

higher use category should be placed in the 

higher category. 

At Level II, Forest Land will be divided into 

three categories: Deciduous, Evergreen, and 

12 

Mixed. To differentiate the three, sequential 

imagery, or at least imagery during the period 

when deciduous trees are bare, will be necessary. 

04-01. DECIDUOUS FOREST LAND 

Deciduous Forest Land includes all forested 

areas in which the trees are predominantly those 

from which the leaves fall at the end of the 

growing period. In most parts of the United 

States, these would be the hardwoods, such as 

oak, maple, beech, ash, hickory, and aspen, and 

the "soft hardwoods" such as sweet gum, 

tupelo, cottonwood, and yellow poplar. Tropical 

hardwoods such as mahogany and ebony are not 

included as they are broad-leaved evergreens and 

hence are included in the Evergreen Forest Land 

category. 

04-02. EVERGREEN FOREST LAND 

Evergreen Forest Land includes all forested 

areas in which the trees are predominantly those 

which remain green throughout the year. Both 

coniferous and tropical broad-leaved evergreens 

are included in this category. In most areas, the 

coniferous evergreens predominate, but the 

mangrove swamps of Florida and some of the 

forests of Hawaii are notable exceptions. The 

coniferous evergreens are commonly referred to 

or classified as softwoods. They include such 

eastern species as the longleaf, slash, shortleaf, 

loblolly, and other southern yellow pines; spruce 

and balsam fir; white and red pines; jack pine; 

hemlock; and cypress; and such western species 

as Douglas-fir, ponderosa pine, redwood, Sitka 

spruce, Engelman!l spruce, lodgepole pine, red 

cedar, larch, hemlock, and white pine. 

04-03. MIXED FOREST LAND 

Mixed Forest Land includes all forested 

areas where both evergreen and deciduous trees 

are growing and neither predominates. 

05. Water 

The Water category includes all areas within 

the land mass of the United States that are 

predominantly or persistently water covered, 
provided that, if linear, they are at least 1/8 mile 

( 660 feet or 200 meters) wid~ and if extended 

cover at least 1/8 square mile or 40 acres. Water 

bodies smaller than these minimums are 

included within the land-use unit in which they 

are located. Sewage-treatment or water-supply 

facilities are a basic part of the urban pattern 

and should be included in the 01-Urban category 

even where the unit is large enough to be 

separately identified. Water bodies that are 

vegetated are placed in the 06-Wetland category, 

or in Forest Land if swamp forests exist. 

There are five Level II categories: Streams 

and Waterways, Lakes, Reservoirs, Bays and 

Estuaries, and Other. 

05-01. STREAMS AND WATERWAYS 

This subcategory includes rivers, creeks, 

canals, and other linear bodies that meet the 

minim urn width requirement of 1/8 mile. 

Occasional constrictions of streams to less than 

1/8 mile may be included to preserve continuity. 

Streams flowing through deltas will be classified 

as water as long as width minimums are met, but 

where there are many distributaries and 

individual streams are less than 1/8 mile wide, 

they will be included in the appropriate land 

use. Where the water course is interrupted by a 

control structure, the impounded area, if it 

exceeds 40 acres, will be placed in the Reservoirs 

subcategory. 

The boundary between streams and lakes, 

reservoirs, or the ocean is the straight line across 

the mouth of the stream unless the mouth is 

05-03. RESERVOIRS 

Reservoirs are artificial impoundments of 

water greater than 40 acres in areal extent, 

whether for irrigation, flood control, municipal 

water supplies, or hydroelectric power 

generation. Dams, levees, other water-control 

structures, or the excavation itself will usually 

be evident to aid in the identification. 

05-04. BAYS AND ESTUARIES 

Bays and estuaries are inlets or arms of the 

sea that extend into the land and as such are 

properly classified in this system only when they 

are included within the land mass of the United 

States. In order that this land mass area be 

commensurate with the area of the United 

States used in compiling census statistics, the 

convention used by the Bureau of the Census in 

setting the outer limits of the United States will 

be followed. Where bays and estuaries are 

between 1 and 10 nautical miles in width, the 

outer limit of the United States will be the 

straight line connecting the headlands except 

where the indentation of the embayment is so 

shallow that the water area would be less than 

the area of a semicircle drawn with this straight 

line as the diameter. In that event the coastline 

itself would form the outer limit of the United 

States. Embayments less than one nautical mile 

in width are classed as 05--01 Streams and 

Waterways. Embayments or portions of 

embayments more than 10 nautical miles wide 

are not considered as included within the land 

more than 1 mile wide. In that case the rule mass. 

given under 05--04 for bays and estuaries is 

followed. 05-05. OTHER 

05-02. LAKES 

Lakes are bodies of water more than 40 

acres in areal extent, but excluding reservoirs. 

Islands within lakes that are too small to 

delineate will be included in the water area. The 

delineation of a lake will be based on the areal 

extent of water at the time the imagery is taken. 

13 

Other water areas include large farm ponds 

that may not be identifiable as reservoirs, other 

water features not mentioned in the preceding 

categories, or combinations of water features 

that cannot be clearly defined. 

06. Nonforested Wetland 

N onforested Wetlands consist of seasonally 

flooded basins and flats, meadows, marshes, and 
bogs. Wetlands are usually relatively level areas. 

Uniform identification is difficult b·ecause the 

wetland areas change as the result of such 

factors as long-term drought, high rainfall, 

seasonal fluctuations in precipitation, and 

diurnal tides. The observations must be 

correlated with tide and weather information to 

obtain consistent results. 

Open saline- and fresh-water areas, sounds, 

and bays are included under 05-Water. Wetland 

areas with a 10 percent forest crown cover, or 

where recent clear cutting has occurred, are 

placed in 04-Forest Land. 

N onforested Wetland may be either 

Vegetated or Bare. 

06-01 . VEGETATED NONFORESTED WETLAND 

Vegetated Nonforested Wetland includes 

areas where the forest crown cover is less than 

10 percent or the vegetation is nonwoody. 

Cattails, tules, and grasses such as Indian rice 

grass and saw grass occur in fresh-water marshes, 

and salt-tolerant grasses such as Spartina occur 

in the salt marshes. 

06-02. BARE NONFORESTED WETLAND 

Tidal flats are the main component. 

07. Barren Land 

Barren land is land of limited ability to 

support life and little or no vegetation. In 

general, it appears to be an area of oily soil, 

sand, and rocks. Vegetation, if present, is more 

widely spaced and scrubby than that in the 

Desert Shrub subcategory of Rangeland except 

when unusual conditions, such as a heavy 

rainfall, occasionally result in growth of a 

short-lived more impressive plant cover. 

Land may be temporarily barren owing to 

man's activities, but such land is usually 

included in another land-use category. 

Agricultural land may be temporarily without 

vegetation because of tillage practices. Sites for 

urban development may be stripped of cover 

before construction begins. Areas of extractive 

and industrial land have waste and tailings 

14 

dumps, and exhausted sources of material 

supply are often evident. 

Level II categories of Barren Land are: Salt 

Flats, Beaches, Sand Other Than Beaches, Bare 

Exposed Rock, and Other. 

07-01. SALT FLATS 

Salt flats are the flat-floored bottoms of 

interior desert basins. For a short time after a 

cloudburst, they may be covered by a sheet of 

water, or playa lake. On vertical air photographs 

they appear as white scars in the desert because 

the soil, flatness, and color cause a diffused 

reflectancy much higher than the albedo of 

other desert features. 

07-02. BEACHES 

Beaches are the smooth sloping 

accumulations of sand and gravel along 

shorelines. The surface is stable inland, but the 

shoreward part is subject to erosion by wind and 

water, and material is deposited in protected 

areas. The Beach category is not used if there is 

vegetative cover or another land use. 

07-03. SAND AND OTHER THAN BEACHES 

Sand Other Than Beaches is composed 

primarily of dunes, accumulations of sand of 

aeolian origin. Dunes are most commonly found 

in deserts although they also occur on shore and 

strand lines, coastal plains, river flood plains, 

deltas, and in periglacial environments. They are 

of various shapes, the crescentic being the most 

elementary, and range in size from diameters of 

a few to several thousand meters and in height 

from one to several hundred meters. Isolated 

crescent-shaped dunes migrate freely, but 

longitudinal dunes tend to remain nearly fixed 

in position. 

07-04. BARE EXPOSED ROCK 

The Bare Exposed Rock category includes 

areas of bedrock exposure, desert pavement, 
scarps, talus, slides, volcanic material, and other 

accumulations of rock without vegetative cover. 

07-05. OTHER 

This subcategory is used for a mixture of 

Barren Land features or when a Barren Land 

subcategory cannot be positively identified. 

08. Tundra 

Tundras are cold treeless lands, primarily in 

Alaska, with a vegetative cover of moss and 

lichen, grasses, and shrubs. The tundra zone can 

be divided into three subzones on the basis of 

vegetative cover: an arctic subzone characterized 

by an interrupted cover of sparse moss and 

lichen sedges: a typical tundra subzone 

characterized by various types of moss and 

lichen sedges and rare shrubs in river valleys; and 

a shrub tundra subzone, characterized by birch 

and willow shrubs together with mosses, sedges, 

and grasses. Mountain tundra, along the 

mountain tops, extends well to the south and is 

enriched by alpine flora. 

The interfaces of Tundra to Permanent 

Snow and Icefields and to Water are fairly easily 

determined if the imagery is taken in late 

summer. Between Forest Land with a light 

crown cover and Tundra, the boundary tends to 

be transitional over a wide area and is also 

uneven, as changes in growing conditions bring 

about protuberances of brushland into Tundra 

areas. Distinguishing between Tundra and 

Nonfor~sted Wetland is difficult where there is a 

hummocky landscape with intervening areas of 

standing water. Flooded portions may vary in 

size owing to seasonal changes in depth of frost, 

amount of precipitation, and evapotranspiration 

potential. The ratio of flooded land to 

vegetation is the basis for decision. The Barren 

Land-Tundra interface occurs where one or 

more of the vegetative growing factors are 

deficient. The boundary will be difficult to 

establish. 

09. Permanent Snow and lcefields 

Permanent Snow and Icefields are those that 

survive summer ablation. Snow, firn, icepacks, 

15 

icecaps, and glaciers are included and the 

underlying mass may be either land or water. An 

average frontal position over a period of a few 

years would be the most desirable border, but an 

expedient delineation can be made through 

observations at the time of maximum retreat, 

probably during August in the northern 

hemisphere. The abutting land would most 

probably be classed as Water, Barren Land, 

Tundra, or Nonforested Wetland. 

Selected References 

Anderson, James R., 1971, Land use classification 

schemes used in selected recent geographic 

applications of remote sensing: Photogramm. Eng., 

v. 37, no. 4, p. 379-387. 

Avery, T. Eugene, 1968, Interpretation of aerial 

photographs [ 2d ed.] : Minneapolis, Burgess 

Publishing Co., 324 p. 

Barlowe, Raleigh, 1972, Land resource economics [2d 

ed.]: Englewood Cliffs, N.J., Prentice Hall Inc., 

585 p. 

Burley, Terence M., 1961, Land use or land utilization?: 

Prof. Geographer, v. 13, no. 6, p. 18-20. 

Canada Department of Forestry, 1966, The Canada land 

inventory: Ottawa, Canada Dept. Forestry, 61 p. 

Clawson, Marion, and Stewart, Charles L., 1965, Land 

use information. A critical survey of U.S. statistics 

including possibilities for greater uniformity: 

Baltimore, Md., The Johns Hopkins Press for 

Resources for the Future Inc., 402 p. 

Cline, Marlin G., 1949, Basic principles of soil 

classification: Soil Sci., v. 67, p. 81-91. 

Hardy, Ernest E., Belcher, Donald J., and Phillips, 

Elmer S., 1971, Land use classification with 

simulated satellite photography: U.S. Dept. 

Agriculture Econ. Research Service Agr. Inf. Bull. 

352 p. 

Marschner, F. J., 1959, Land use and its patterns in the 

United States: U.S. Dept. Agriculture Agr. Research 

Service Agr. Handb. 153, 277 p. 

National Academy of Sciences, 1970, Remote sensing 

with special reference to agriculture and forestry: 

Washington, D.C., Natl. Acad. Sci. 

New York State Office of Planning Coordination, 1969, 

Land use and natural resources inventory of New 

Yor~ State: Albany, New York State Office 

Planning Coordination, 67 p. 

Society of American Foresters, 1967, Forest cover types 

of North America: Washington, D.C., Soc. American 

Foresters. 

Stoddart, Laurence A., and Smith, Arthur D., 1955, 

Range management [2d ed.]: New York, McGraw 

Hill Book Co., 433 p. 

U.S. Congress, 1936, The Western Range: U.S. 74th 

Cong., 2d sess., Senate Doc. 199. 
U.S. Arctic, Desert Tropic Information Center, Research 

Studies Institute, 1955, Glossary of arctic and 

subarctic terms: Maxwell Air Force Base, Alabama, 

ADTIC Pub. A-105. 

U.S. Department of Agriculture Conservation Needs 

Inventory Committee, 1966, National handbook for 

updating the conservation needs inventory: 

Washington, D.C., U.S. Dept. Agriculture Conserv. 

Needs Inventory Comm., 75 p. 

16 

U.S. Department of Agriculture Soil Conservation 

Service, 1962, Classifying rangeland for 

conservation and planning: U.S. Dept. Agr. Handb. 

235. 

U.S. Urban Renewal Administration, Housing and Home 

Finance Agency, and Bureau of Public Roads, 1965, 

Standard land use coding manual, a standard system 

for identifying and coding land use activities: 

Washington, D.C., U.S. Govt. Printing Office, 111 p. 

G P 0 935-919