Ministry of Environment

Soils

4.3 The Canada Land Inventory Period 1965 - 1975

P.N. Sprout

Introduction

The period 1965 to 1975 was the coming-of-age of soil and terrain surveys in British Columbia. It was the period when soil surveys changed from being mainly agriculturally oriented to providing basic information for a wide variety of resource uses. It was the period of large increases in the resources allocated to soil and terrain inventories and to the area covered annually by such surveys. It was the period when soil survey activities changed from being primarily fact gathering missions to programs whose objectives were to supply information relevant to land-use planning and management.

The result of these changes was a de-emphasis on classifying soils and an emphasis on developing methods of mapping soils quickly and interpreting the gathered data for a wide range of uses.

The changed emphasis came early in the period and was spurred by the Canada Land Inventory program (referred to as the CLI program). This fostered interagency communication and promoted the assessment of the natural capability of land. The activities in British Columbia were part of a Canada-wide inventory of land capability which was designed to provide a basis for resource and land-use planning. They were undertaken as a cooperative federal-provincial program and initially were administered under A.R.D.A. (Agricultural Rehabilitation and Development Act, later changed to Agricultural and Rural Development Act).

At first the CLI program was oriented toward multiple-use areas of the province in which agriculture was one of the main users. Later it was expanded to include a much larger part of the province which included considerable multiple-use land and a much higher forestry potential (see Figure 4.3.1).

To meet the administrative and coordinative demands of the programmer, a "Soil Capability for Agriculture and Forestry Committee" was formed in 1964. The committee was active until 1972 and administered most of the soil survey activities during the 1965-1972 period. Subsequently this was done through the B.C. Land Inventory Group in cooperation with the Canada Agriculture Soil Survey Unit.

Figure 4.3.1

By 1972 there was less emphasis on land capability assessments sponsored by the CLI programmer and more on meeting specific requests generated within the province. This general interest in the use of soils information was partly a reflection of the success of the CLI programmer, and partly due to an increase in competition for the province's natural resources. Soil survey information was in demand as an aid to making decisions on land-use, in preparing impact assessments prior to development, and in preparing resource folios. Information on other related land-based resources was also being requested, and a more holistic approach to inventorying land was required. This led to the concept of integrated resource or biophysical surveys whereby terrain features, vegetation, aquatic systems and climate were surveyed along with the soils.

Until this time soil surveys in Canada had traditionally been sponsored by Agricultural Departments, and this was also the case in British Columbia. But with integrated resource surveys and the broad application of soils information for other resource uses, a new sponsoring agency was needed with a broader mandate. This resulted in 1974 in the shift of soil survey responsibilities from the B.C. Department of Agriculture to the Resource Analysis Unit of the Environment and Land Use Committee Secretariat, the staff arm of Environment and Land Use Committee. This Committee is a provincial cabinet committee comprised of Ministries whose activities affect the natural resources of British Columbia. The shift encouraged and solidified the concept of integrated resource surveys in British Columbia. It also encouraged the process of using soil and terrain information in the land-use planning process.

Soil Survey Techniques

In 1965 the sudden widespread demand for information generated by the CLI programmer required new survey techniques. Reconnaissance surveys were emphasized having a field scale of 1:50,000 or 1:63,360, and a publication scale of 1:125,000 or 1:126,720. The surveys had to cover terrain which varied in accessibility from good to non-existent. This meant the old approach of going from the specific to the general, that is, the process of digging numerous holes to identify soil series and as a means of establishing mapping boundaries was not practical. Instead an approach was applied which was nearly the reverse. Map boundaries were established first by using stereoscopic pairs of air photos to identify landforms that were distinguished by their surface form and shape. Lines were drawn where distinctive and repeated patterns could be distinguished. Since certain shapes and patterns are characteristic of certain depositional and erosional processes, inferences could be drawn about the materials making up the landform. The landforms and position of the boundaries were then checked in the field and the soil units occurring on the landforms were identified. Where access by road was possible this checking was done by ground transportation; where road access was not possible, spot checks were made by helicopter.

In general, the pattern of soils occurring on the landforms was too complex to permit the identification of all the soil series which occurred (see definition Part 2.2). Such an approach would have retarded the progress of the surveys and would have resulted in the final maps being unduly cluttered and complex. Instead, in 1967 the use of soil associations was instituted. As indicated in Part 2.2, a typical soil association consists of a number of soils, generally soil series, which may vary from well drained to poorly drained. However, not all of the soils making up an association will occur together. So various combinations of them are mapped in different "soil association map units". For example one map unit may contain only the well drained soil, while a second map unit may contain the well drained and the poorly drained soil. Being able to identify the soil in any particular place is important when land-use interpretations and recommendations are being made. This method of mapping proved very successful and was still being applied at the end of the 1975 period.

The soil series has always played a key role in detailed soil mapping at scales larger than 1:30,000. During the period when the CLI program was demanding most of the resources of soil survey agencies, a number of special projects were conducted at these detailed scales. The largest of these was the survey of the Lower Fraser Valley (scale 1:24,000), but a number of smaller surveys were also completed, some related to irrigation districts, ARDA sponsored community pasture projects and Indian Reserves. Some of these were carried out at scales as large as 1:6,000. In all cases, soil series and complexes of soil series comprised the map units. Their identification required an intensive field examination of the soils and landscape, and this in turn ensured good definition of the various soil properties and an accurate placement of the soil boundaries. The information collected depended upon the objective of the survey, but typically characteristics such as texture, drainage, structure, reaction, salinity and nutrient content were identified in considerable detail. This detailed definition allowed the user to apply the information easily and confidently. However, increased precision is costly and detailed surveys are restricted to situations where the impact and the benefits in relation to the cost are high.

With the expansion of reconnaissance soil surveys into forested and mountainous areas, a number of technical soil classification problems were encountered. Inadequacies were most evident in the Brunisolic, Podzolic and Organic orders (see Part 2.3) and in high elevation or alpine soils. Increasingly precise morphological and chemical criteria had resolved many of the problems by 1974 and allowed for a better fit between the classification system and the natural environment. More specific but important from the standpoint of soil use and biological productivity was the occurrence of surface churning and the downslope movement of seepage water on the long steep slopes so prevalent in much forested terrain in British Columbia. Similarly, the presence of hard and nearly impenetrable pans was noted in the subsoil of many coastal and some interior soils. The identification and characterization of such features during this period allowed the surveys to proceed in a uniform, precise manner.

When dealing with lands in their natural state, one is mainly concerned with characterizing and manipulating the total ecosystem. It became evident quite early in our attempts to inventory forest lands that the information collected by traditional soil surveys, however important, comprised only one aspect of the total resources. To obtain the complete picture also required inventories of climate, vegetation, aquatic systems and landforms. Thus the concept of biophysical or integrated resource surveys began to take shape in the mid-1960s, to be applied generally from about 1970 onward. The application was in some respects forced by the increased demand for multi-resource information. However, the need was anticipated several years earlier as evidenced by a meeting convened in 1962 by R. Spilsbury (B.C. Forest Service), and the resultant pilot projects at Minnie and McGillivray Lakes. These projects were primarily concerned with developing a method of classifying and mapping soils through the integration of information on soils, landforms and vegetation. Valuable data were gained from these projects; they introduced the principle of airphoto interpretation as a means of pre-mapping forested terrain. The biophysical mapping concepts were finally formalized and documented in 1967 under the auspices of the National Committee on Forest Land.

CLI Program

The impetus for conducting reconnaissance soil surveys over large areas of British Columbia was initially supplied by the CLI program in 1965. The objectives of the program were firstly to undertake a country-wide assessment of resource supplies which could be set against a long term assessment of resource needs, and secondly to make possible systematic studies of problems of resource management and development in all fields. The program sponsored assessments of land capability for agriculture, forestry, recreation, wildlife, waterfowl and present land use. In British Columbia, soil survey information was used as the underpinning for agriculture and forestry capability ratings and subsequent discussion of the program will be restricted to these aspects.

Both the Agriculture and Forestry Capability Classification systems rated the soils into seven classes. In the Agriculture system the mineral soils were ranked according to their capability for producing a range of common field crops. In the Forestry system, all mineral and organic soils were rated on their inherent capability for growing commercial timber. Capability for Forestry was therefore based on productivity. Agriculture Capability ratings were initially applied only to previously surveyed areas, but the first Forest Capability investigations consisted of pilot projects in the Prince George, Princeton and East Kootenay areas. This initial work resulted in adjustments to both rating systems, the better to depict conditions in British Columbia. Once these problems were solved the work proceeded rapidly with survey activities reaching a high level by 1968 of nearly 3 million ha, increasing gradually to 1975 with 5.9 million ha. The program ended in 1975. In spite of these efforts, not all of the target area was covered (see Figure 4.3.1). Notable exceptions were the west Chilcotin, the area north of the Peace River block, and the east-central part of the province. For those areas which were surveyed, maps showing capability ratings for agriculture and forestry were published at a scale of 1:126,720. This contrasts with other resource capability maps which were published at 1:250,000 for the total of the Canada Land Inventory area.

One of the earliest uses of the CLI information were broad regional land-use recommendations based on a comparative analysis of the capability ratings for each resource. This procedure was termed a Land Capability Analysis and was undertaken for seven regions in the Central, Southern and Peace Rivers areas. The product was a map at a scale of 1:250,000 showing the land's best use capability following an examination of the individual capabilities for agriculture, big game, forestry, recreation and waterfowl, and for special uses such as native range. The information was used for a short period as a guide in setting land alienation policies.

An example of the use of CLI data for planning was the designation of Agricultural Land Reserves in British Columbia. A Farm Land Preservation Policy was introduced by Order-in-Council in December 1972, followed by the Land Commission Act in April 1973. This policy placed a moratorium on the subdivision of all farmland as defined by the Taxation Act, and on all lands with Agriculture Capability Classes 1 to 4. The moratorium was in effect only until the lands were permanently designated as Agricultural Reserve after a complex review and referral procedure. A basic prerequisite of the review process was the production of maps for all of the province indicating the location of lands which were proposed to be reserved for agricultural use. Compilation of the maps was based on lands with a capability for agriculture rating of Classes 1 to 4. In ranching areas where grazing lands were an integral part of the operation, Class 5 and 6 lands capable of use for spring and fall grazing were also included. More than 300 map sheets at 1:50,000, encompassing more than 4 million ha of land proposed for Agricultural Reserve were prepared within a few months. Without the basic information provided by the CLI program, the task would have been impossible.

The CLI program was a success in many ways. Besides the main objective of producing a broad scale assessment of soil and land capability, there were desirable spin-offs: it gave a much needed impetus to the federal and provincial soil survey programs; it created a large data base on soil and terrain which could be used for other purposes; it fostered communication and cooperation in relation to resource management and planning; and it created an awareness of the value of soil interpretations and of the need to integrate the components of the ecosystem. The capability data produced by the program are still the main sources of information available for management and planning over large areas of British Columbia. The major drawback is the broad scale on which the surveys were conducted. They were designed to provide an input to regional land-use planning and are well suited for the purpose; but the data are too general for most management activities although many agencies have used them with varying success in the absence of more relevant information.

Special Purpose Surveys and Applications

To make soil survey data useful for land-use planning and management, the information must be reliable, readily available, and in an easily understandable form. The capability maps produced by the CLI program were only the beginning of the kinds of practical applications which could be made. The soil survey reports which were produced from 1965 to 1975 illustrate the gradual transition from very technical reporting on soils to publications which emphasize use and management for multi-resource purposes. The report format was itself simplified and made more appealing by eliminating or appending much of the technical data.

Besides making the report user-oriented, a major effort was made to shorten the period between completing the inventory and reporting the results. One means of accomplishing this was to produce interim copies of both maps and reports. Computer storage of data facilitated the manipulation of the data and its accessibility to other agencies.

Many of the requests received could not be met from the data accumulated in the CLI program. This generated the need for more specialized surveys, often at detailed scales, and for new ways of applying the information.

Some of the demand could be met by the traditional soil survey organizations of the Federal and Provincial governments. Some could not, and this led to the hiring of pedologists by private companies and other government agencies. Some large forest companies undertook their own soil and terrain surveys and initiated specialized applications for them. The Federal and Provincial soil survey units meanwhile became more specialized. The Federal unit undertook an increased correlation function to ensure standardization and integrity of the information being collected by the various agencies. Its role in research was also strengthened.

The Provincial unit concurrently geared up to conduct more special purpose surveys and to make more sophisticated interpretations. By the end of the 1965 to 1975 period, the interpretations covered not only the traditional resource fields of agriculture, forestry, recreation and wildlife, but also included engineering, urban development and regional planning. Their preparation used not only soils data, but also the related aspects of climate, terrain systems, aquatic systems and vegetation. Truly, soil surveys had come of age and were in a strong position to meet the demands of the next decade.

Further Reading

  • Anonymous, 1970. The Canada Land Inventory: Objectives, Scope and Organization, Report No. 1, second edition, 61 pp.

    This report describes the Inventory, with brief summaries of the classifications used.

  • National Committee on Forest Land, 1969. Guidelines for Bio-Physical Land Classification. Canadian Forestry Service Publication No. 1264.

    A description of the methods to be used in the mapping of land using the Bio-Physical Land Classification.

  • Staff of the Resource Analysis Unit, 1976. Terrain Classification System, E.L.U.C. Secretariat, Victoria.

    Descriptions and definitions of a mapping system for terrain.

The following are all soil surveys published during the period, which include technical soil descriptions and chapters on soil capability for various uses.

  • Valentine, K.W.G., 1971. Soils of the Tofino-Ucluelet Lowland of British Columbia, B.C. Soil Survey Report No. 11, Canada Dept. of Agriculture, Ottawa, 29 pp.
     
  • Valentine, K.W.G., 1971. Soils of the Fort Nelson Area of British Columbia, B.C. Soil Survey Report No. 12, Canada Dept. of Agriculture, Ottawa, 60 pp.
     
  • Lord, T.M. and A.G. Green, 1974. Soils of the Tulameen Area of British Columbia . B.C. Soil Survey Report No . 13, Canada Dept . of Agriculture, Ottawa, 163 pp.
     
  • Cotic, I., 1974. Soils of the Nechako-Francois Lake Area. Interim Report. British Columbia Dept. of Agriculture, Victoria, 218 pp. (A)
     
  • Runka, G.G., 1974. Soil Resources of the Smithers-Hazelton area. Interim Report, British Columbia Dept. of Agriculture, Victoria, 234 pp. (B)
     
  • Green, A.J. and T.M. Lord. Soils of the Princeton Area. B.C. Soil Survey Report No. 14, Canada Dept. of Agriculture, Ottawa, (in press).