Land clearing research and related studies have been conducted for a period spanning 10 years in the low jungle of the Amazon at Yurimaguas, Peru. Three distinct research phases have been conducted at this site. Results of Phase I indicated that land clearing using a D-6C bulldozer with a straight blade compacted the soil and drastically reduced the infiltration rate. Crop yields were reduced significantly. The soil that was compacted in Phase I was successfully reclaimed in the Phase II study in 1980-81, during which time the two deep tillage treatments, subsoiling and chiselplowing, produced the greatest corn and soybean yields. Results of the Phase III study have not been completely analyzed, but a cursory examination of the results suggests that shear blade bulldozer clearing is preferred over that of the straight blade.-from Authors