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TABLE 3.7.Cost of Crop Insurance in Oklahoma, 1940-63

Source: Walker and Cox 1967, 53.

TABLE 3.8. Adoption of Soil Conservation Practices, cat 1965

Source: Saarinen 1966, 85.
Note: Because of overlap, percentages may total more than 100 per cent.

The diffusion of innovations

The diffusion of innovations over space through time has been the subject of many studies in geography but Bowden's study of the decision to irrigate in the central Plains illustrates both the complex paths of the innovations into a community and the uneven spatial pattern which results (Bowden 1965). It is not therefore surprising that there is evidence to suggest that adoption of conservation innovations similarly has been neither uniform in space nor consistent over time. Saarinen's study showed that in 1965 strip-cropping and stubble-mulch adoption varied widely between his six sample counties (Table 3.8), and he noted that "perception of the [conservation] practice as effective does not necessarily lead to adoption"-often for economic reasons (Saarinen 1966,92). In 1978 in the heart of the old Dust Bowl-the panhandles of Oklahoma and Texas-the detail of adoptions varied from county to county. Thus, in Sherman County, Texas, a local official estimated that 60 per cent of the county farmers were still practicing monoculture wheat cropping year after year without any fallow period (Lundberg 1978). In adjacent Texas County, Oklahoma, the Extension Agent estimated that of the county farmers "30 per cent used stubble mulch tillage all the time, 50 per cent used stubble mulch tillage only part of the time, and 20 per cent did not use it at all," preferring the one-way disc and traditional clean fallow techniques frowned upon by conservationists since the 1930s (Howell 1978)! The stubble-mulch technique (developed in Nebraska in 1938) had reached the Panhandle by the late 1950s but was still not completely accepted as a regular strategy by a majority of the farmers. farm ownership

A high turnover of farm operators has been a feature of the Great Plains from its earliest settlement. Whether forced out by environmental or economic stresses or voluntarily leaving to take up alternative opportunities, the farm population has been highly mobile. In 1953 an official report suggested that less than half of the land was still being farmed by farmers who had experienced the Dust Bowl (USDA 1953,14). Saarinen suggested a turnover of over 50 per cent between 1954 and 1961 in the central Plains (Saarinen 1966, 97n). Detailed evidence of recent farm-turnover figures was not available but field evidence suggested absentee owners (resident outside the country) were 60 per cent of Greeley County, Kansas, and 70 per cent of Texas County, Oklahoma, owners. When allied with the tendency for past disasters to be forgotten relatively quickly, the most recent generation of farmers and particularly the urban populations neither remember nor under. stand the ravages of nature so apparent during the drought of the 1930s. [Shelterbelts 1976,143]

Such a turnover and continued absentee control may well explain some of the limited success of conservation education programmes. Conservation education

Yet the education programmes themselves seem not to be uniformly applied. A questionnaire survey of education programmes on conservation tillage in each of the ten Great Plains states in 1975 received returns from only six, of which three confessed to carrying out little work at the time. From the minority of reports which were provided, it became evident that some states are currently doing more educational work on conservation tillage than others. It is also apparent that the kinds of educational programs which are called conservation tillage varies [[sic] considerably. It is also evident that there are still many farmers in the Plains that have not adopted conservation tillage practices irregardless [sic] of what the states call their educational programs in Extension. [Jones and Kotich 1976,244]

With a varied input, a varied output/success is only to be expected.

The economic motive

That economic policies, whether at national or farm level, should influence decisions on conservation practices is not surprising, given the commercial market orientation of Great Plains rural production systems. However, a recent review suggests that only since the 1950s have the national farm policies been realized to have implications for farmers' conservation policies (Skold 1977, 150). The basic questions are whether farmers have been encouraged by official commodity price manipulation policies to invest in conservation practices and if so, whether the farmers have in fact found it profitable to do so.

At the height of the Dust Bowl officials had little difficulty recruiting farmers to the conservation practices. With their income from the farm close to zero and the immediate outlook uncertain, there was an economic incentive to cooperate-they were paid (initially for petrol for their tractors in the emergency tillage operations, or for seed for a new crop, or for their unsaleable starving livestock). Later the payments were for conversion of cropland to grassland and for carrying out conservation practices. With their fields eroding, no more seed, nor credit at the bank, there were few alternatives.

Since the Dust Bowl era, however, farmer cooperation appears to have been harder to achieve. In part the reason seems to have been that official price-support schemes have been seen by farmers as temporary and as a stimulus to exploitative rather than conservation-oriented farm management. Guaranteed prices in and after World War II encouraged the intensification of production as well as the bringing of new lands into crop production, which was of concern during the droughts of the 1950s: since 1973 and the increased demand for food grains "the economic climate has definitely favoured present resource use at the expense of resource conservation concerns" (Skold 1977, 163). Even the Soil Bank scheme of the 1950s seems to have had the same economic attractions as the earlier Dust Bowl schemes. Hewes noted that

"the program broke the effect of the serious and prolonged drought by providing an income to dry-land farmers who were in a depressed financial position." According to the same source, drought was given as the chief reason for participating by a large majority of farmers, with the establishment of pasture, and health and retirement as other important reasons. [Hewes 1967, 385]

The acreage reserve option provided windfall income and the conservation reserve system (by which cropland was sown to grass and leased to the federal government for up to ten years from 1956 onwards) appears to have been particularly attractive to suitcase farmers who "chose to
collect from the government rather than to take their chance on wheat" (Hewes 1973,140). Once the economic incentive had been offset by price rises, however, there was strong motive to make a quick profit again by taking land out of the reserve. Further, the main intention of the Great Plains Conservation Program (begun in 1956 in association with the Soil Bank scheme) was to encourage the regressing of cropland. USDA officials anticipated that three-qarters of the $150 million in allocated funds would be so used. In fact, by the end of the programme in 1969 only 15 per cent had been so used: "Ten per cent went for reseeding rangeland, the balance for such things as terraces, stock ponds, and irrigation" (The Farm Index, Nov. 1970, 27). The farmers cooperating seem to have used the funds to upgrade the "improvements" on their properties (and therefore increase their value) as much as to carry out conservation practices!

In detail, indeed, there is evidence that the conservation practices, unless directly subsidized by government, are too expensive for farmers. In 1969 a suggestion was made that the costs of conservation practices would escalate beyond the capacity of the farm to cover them (Cotner et a/. 1969, 206-207). A study in southeastern Nebraska in 1977 showed that to reduce soil erosion to the acceptable 5 tons per acre (1.96 tonnes/ha) meant a decline of 16 per cent in farm returns (Skold 1977, 156). Where stubble mulching is practiced the farmer in fact gets a crop every second year-for the Texas Panhandle research plot yields over 35 years showed the wheat-fallow average as 15.6 bushels/acre (or 7.8 bushels/acre/year) compared with 10.3 bushels/acre /year for the continuously cropped plots. Only in the central Plains did the wheat-fallow system provide better average yields (Johnson and Ungar 1976, 97). In this context, the evidence of a trend back towards continuous cropping, particularly since the mid-1970s, is therefore understandable.

Conclusion: Perception and Desertification

Although restricted both in the time available and the scope of research attempted, sufficient evidence has been accumulated to suggest first that there seem to be several and varying perceptions of soil erosion on the southern Great Plains and second that these perceptions seem to influence actions by the perceivers.

From the official viewpoint, particularly of the Soil Conservation Service, soil erosion is an ever-present threat which still looms over the Plains. For the farmers it appears to be rather an occupational hazard, a problem which they are prepared to live with. For the officials, the significance of soil erosion lies in the deterioration of part of the nation's resources-the soil; but also, and increasing in importance recently, soil erosion is seen as a major source of environmental pollution, which given the general public's continuing concern (R.C.M. 1978) will require careful control. For the farmers, soil erosion appears to be merely an inconvenience or additional cost in their budgets.

As a result, large sums of public money have been and are being spent on soil conservation projects of various kinds, but the problem of soil erosion remains, and the farmers, for whom the projects have been devised, appear to be less than completely convinced of their worth. Of much more relevance to the farmers are the prices for their produce and the profitability of their activities. Given the commercial context in which they operate I find their attitudes perfectly logical.

A final question may be asked: "Will desertification continue in the Great Plains either gradually or rapidly (as in another 'rust Bowl' situation}?" Recent academic opinions have been generally optimistic (Borchert 1971; Bowden 1977; Warrick 1975), seeing an increase in farm size, improvement in farm management, and continued federal supports for the farm sector of the economy. Radical academics, however, have been much less sanguine, pointing out the manipulation of the federal conservation programmes by unscrupulous operators and calling for "vigorous new federal programs directed toward maintaining the social and economic viability of small family farms" (Raitz 1975,9). Just how such programmes will keep out the manipulators is not indicated. Like the radicals, l must confess to a greater pessimism, but for different reasons- an assessment of the future natural event systems on the one hand and the role of the perceptions of officials and farmers on the other.

Although not discussed in detail in this report, most climatologists consider that the variability of the Great Plains climate will continue with swings from more humid to more arid seasons at intervals of approximately 21 years (Borchert 1971) Indeed Borchert's forecast of the next drought as coming in the mid-1970s was remarkably accurate, if modest in the area predicted as affected (Fig. 3.6). There is no statistical or meteorological reason why the next drought might not be much severer than any previously experienced. Two or 3 years of severe drought (Palmer Index = -4) in succession would create massive soil erosion under present tillage practices and with the apparently increasing use of continuous cropping or reliance on emergency tillage in drought conditions. If for a longer period, Weakley's comment of 1962 is still valid: "No presently known land use or conservation practice can be expected to successfully cope with the effects of a severe drought of 20 years' duration" (quoted in Wadleigh 1969). Even if the swings of the seasons are no greater than those previously experienced, the impact of drought is likely to increase because of the recent expansion of irrigated farming, which has already produced significant reduction of local water tables and fears for their ultimate exhaustion (Badger and Schmedemann 1971). The peak of land irrigated on the Plains appears to have been reached or is close to being reached, so that abandonment of previously irrigated land may result in the future. The short-term answer to drought adopted since the 1960s by many farmers may produce a greater long term desertification threat, once this defensive "option" has been used up.

FIG. 3.6. Patterns of Drought in the USA, 1934-36, 1954-56 and 1976-77

Source: USDA Weekly Weather and Crop Bulletins.

The history of official intervention in the agricultural sector of the US economy since the 1930s shows, in the alternating pressures for free market and controlled market situations and the associated short-term policies for the "setting aside" of productive lands then sudden switch to the release of such lands for the required increase in produce, an ambivalence which has played havoc with conservation policies. Government departments have spoken with different tongues and the "experts" have squabbled amongst themselves. Even now the debate as to how much soil erosion should be tolerated is still unresolved-(Stocking 1978). Given the continued scientific investigations, innovations in agricultural technology will certainly reduce erosion losses; but from past experience their diffusion will be sporadic and incomplete-indeed the gap between the innovative and conservative farmers may widen because of the rate of current innovations. The "hot spots" of traditional practices are likely to remain.

It is unlikely that farmers or the increasing "agri-businessmen and women" will accept conservation technologies any faster in the future than they have in the past. Quite apart from the nature of the diffusion process noted above, their overall economic motives will cause them to evaluate whether their farm profits should come from crop and livestock sales, oil revenues, land sales, or conservation practices. Their choice may depend, among other things, upon whether they are new to the business, suitcase farmers, over 60 years old, or wish to retire to the west coast. Most of the conservation practices cost money- opportunity costs of fallowed or strip-cropped unproductive land, costs of chemical sprays for minimum tillage- money, which if they are lucky and the seasons favourable, they might not need to spend. If drought returns they may prefer to rely on emergency tillage-using their existing equipment. If they are lucky they will keep some of their soil; if not a miniature Dust Bowl will result.

This report lacks sufficient depth to decide how great the threat of future desertification on the Great Plains is but there is no doubt in my mind that a threat does exist-a threat whose existence is a result of conflicting perceptions of the problem of soil erosion.

Abbreviations

GPAC Great Plains Agricultural Council

ICASALS International Center for Arid and Semi-Arid Land Studies, Texas Tech. University, Lubbock, Texas

USDA United States Department of Agriculture

Notes

1. ·'Moderate means that plant cover has been degraded to a point where the range condition could be only fair, or there are indications of accelerated wind or water erosion in the form of hummocks, noticeable small dunes, and noticeable small gullies, or soil salinity is reducing crop yields moderately. Severe desertification means that undesirable fortes and shrubs have replaced desirable grasses or have spread to such an extent that they dominate the flora, or sheet and water erosion have largely denuded the land of vegetation, or salinity controllable by drainage and leaching has made the land unsuitable for crop production" (ICASALS Newsletter, 10[3] :2, 1977)

2. The US Soil Conservation Service defines land damaged by soil erosion as: "Land where soil removal or deposition by wind erosion has been enough to subject it to further erosion hazards, materially lower yields, or impair inherent productive capacity. For cropland this means surface soil removed, surface swept smooth, and depressions and hummocks or fence-row drifts formed. For range or other land it means surface soil removed, plant crown exposed, hummocks or fence-row drifts formed, and deposition covering vegetation" (quoted in Lyles 1976, 27)

3. Several studies of the perception of the climate of the Great Plains indicate the fluctuating appraisals of a variable climate (Bowden 1976; Kollmorgen and Kollmorgen 1973; Lawson 1974). Such studies provide complementary documentation to this report but have not been reviewed here, although any comprehensive study of perception of desertification on the Great Plains would need to do so.

4. In the case of Nebraska alone in 1978 there were 81 county extension agents, and 4 agricultural research stations with a total staff of 59.

5. Lack of time and the poor condition of the roads in May 1978 prevented a full survey of the western segment of Hewes's traverse.

6. The technique received official recognition through the work of F, L. Duley, first director of the Soil Conservation Service Research Station at Lincoln, Nebraska (Russet 1976), but may have been in use in Montana in the 1920s (Hewes, personal communication in 19791.

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