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美国东北部山岳地带的行播作物因水土流失而减产。在两块易结皮的土壤上进行的４种耕作试验──免耕、作物行间翻底土耕种、凿形松土犁耕以及铧式犁耕。其残余物覆盖率分别是：免耕为７５％～８７％，铧式犁耕为 １％，凿形松土犁耕为 ３８％～２７％。经过两年时间，理德斯威尔土壤容重平均值为：免耕１．５６ｔ／ｍ~３，凿形松土犁耕１．４８ｔ／ｍ~３，铧式犁耕１．４６ｔ／ｍ~３。试验中产量最低时，铧式犁耕为 １．２３ｔ／ｈｍ~２，免耕为２．９７ ｔ／ｈｍ~２，凿形松土犁耕为２．４４ｔ／ｈｍ~２。１９８７年，按行翻底土耕作，其平均产量为３．６９ｔ／ｈｍ~２。试验表明，在地面保留作物残茬的耕作措施可减轻或消除地表结皮，增加渗入量、降低水土流失量、从而提高粮食产量。
Crops sown in mountainous areas of the northeastern United States have been cut due to soil erosion. Four tillage tests conducted on two crusty soils - no-tillage, under-tillage in crop lines, chisel-loosening plows and plowshare. The residue coverage rates are: no-till for 75% ~ 87%, share plowed 1%, chisel loosening plow 38% to 27%. After two years, the average soil volume of Richardsville soil was: 1.56t / m ~ 3 for tillage, 1.48t / m ~ 3 for chisel loosening soil plow, 1.46t / 3. At the lowest yield in the experiment, the average yield was 1.23 t / hm 2 for plowshare, 2.97 t / hm 2 for no tillage, and 2.44 t / hm 2 for tillage loosening plow. In 1987, Line overturning tillage, the average yield of 3.69t / hm ~ 2. Experiments show that tillage on the ground to retain crop residues can reduce or eliminate surface crust, increase infiltration, reduce soil erosion, thereby increasing food production.