agricultural depression and World War II, and then 

 increased at a slowly declining rate in the postwar 

 period. Estimates of remaining potential for 

 agricultural drainage declined steadily as drainage 

 was actually accomplished. Government 

 assessments of drainage potential remained low in 

 the 1960's and early 1970's, reflecting USDA policy 

 denying technical and financial assistance for 

 drainage (9). However, drainage installation during 

 this period increased, partly because of more op- 

 timistic private assessments of drainage potential 

 and partly because of drainage improvements on 

 existing cropland. 



Remaining Wetlands 



Several key characteristics of remaining non- 

 Federal wetlands inventoried in the 1982 NRI 

 (USDA Soil Conservation Service), put wetlands 

 subject to agricultural conversion into perspective. 



Characteristics of Remaining Wetlands 



Most non-Federal wetlands are privately owned 

 (table 4). States own about 13 percent of non- 

 Federal wetlands. Almost all palustrine wetlands, 

 those most likely to be farmed, are owned privately. 



More expansive assessments of drainage potential 

 on new cropland in the mid-1970's were tempered 

 by environmental activism, which gradually forced 

 an awareness of the importance of wetlands for 

 wildlife and fisheries. Low official estimates of 

 wetlands suitable for drainage exclude all but the 

 most favorable candidates. Even with the economic 

 prospects faced by farmers today, private wetland 

 owners may see potential profit in converting 

 wetlands for farming. There are few barriers to pre- 

 vent such conversion. 



According to the National Wetlands Status and 

 Trends Analysis (table 3), 87 percent of the 13.8 

 million acres of wetlands lost in the 1950's and 

 1960's were converted to farmland (13). Virtually all 

 of these were classed vegetated palustrine in the 

 most recent Fish and Wildlife Service system (8). 

 While some may have been converted directly to 

 farmland, about half were originally forested and 

 thus may have entered agricultural use after being 

 cut for timber. 



Table 3 — Sources and uses of converted wetlands, 

 United States, mid-1950's to mid-1970's 



Remaining wetlands were classified by their land 

 cover in the 1982 NRI. Shghtly more than half of 

 all non-Federal wetlands inventoried are forested. 

 Of these 42.7 million acres, about a third are in the 

 oak-gum-cypress forest typical of southeastern wet 

 hardwood forests, and about 15 percent each are in 

 the oak-hickory and spruce-fir types of more north- 

 ern wet woodlands. The swampbuster provision in 

 the 1985 farm act applies to "converted wetlands" 

 (Sec. 1201(4)(A), P.L. 99-198), implying that forested 

 wetlands drained to permit timber harvest would be 

 ineligible for farm programs if brought into crop 

 production after removal of the timber. Hence, this 

 sanction would apply to all wetlands converted in 

 the history of agricultural development, regardless 

 of past ownership or uses between conversion and 

 crop production— an interpretation that would be 

 hard to enforce. (For this analysis, the farm operator 

 is assumed to clear the land for crop production.) 



The second largest land cover category (20.9 per- 

 cent) in which wetlands were classed in the 1982 

 NRI is "other lands," a residual category. About 17 

 percent of wetlands are in pasture and range. Only 

 5.6 percent of wetlands is in crops and all of this is 

 palustrine wetlands. 



* = Fewer than 100,000 acres. 



'Detail may not add to total due to rounding. 



Source: National Wetland Status and Trends Analysis (13). 



• = Fewer than 100,000. 

 'Defined in (8). 



Source: 1982 National Resources Inventory, USDA Soil Conser- 

 vation Service. 



