fertilizer use in 1991/92 is expected to increase 2 percent and prices to rise 3 to 4 percent above last spring; while application rates on corn, soybeans, and wheat are anticipated to remain near those of 1990/91. planted area of corn and wheat, the major fertilizer-using crops, is projected to increase, while planted area for cotton and soybeans to decline slightly. nitrogen use is forecast at 11.15 million tons, phosphate at 4.33 million, and potash at 5.26 million. u.s. fertilizer supplies will satisfy greater domestic and export demand at slightly higher prices. exports during 1991/92 are forecast to rise modestly from a year earlier. u.s. farmers can expect 1992 energy prices to remain at or slightly above 1991 averages due to anticipated steady or slightly higher prices for imported crude oil. unit tractor sales decreased 12 percent in 1991 combine sales were down 7 percent. seed use for last year's eight major crops was 5.9 million tons, down 4 percent from the previous year