Updated October, 2005
Fuel Required for Field Operations
The table below contains estimates of the average quantity of diesel fuel required for field operations. The estimates include only the fuel required for actual field work. No allowance is included for machine preparation or travel to and from the field. Because fuel consumption values for any particular operation vary between tractors and soil type, actual fuel requirements may be as much as 35 percent higher or lower than the values listed in the table.
Engine efficiencies increase over time. Older tractors manufactured before 1990 or those in poor repair may use 10 percent or more additional fuel. Older gasoline powered equipment uses about 50 percent more gasoline than the table values indicate.
Fuel requirements for tillage machines were calculated for a central Iowa loam soil. If your soil is heavier, the values in the table should be increased slightly. Values were calculated for a 7-inch plowing depth and 3- to 6-inch operating depth for other tillage machines. Field speeds were assumed to be 4 to 6 mph for all tillage operations, 5 mph for planting and spraying, 4 to 5 mph for forage harvesting machines, and 4 mph for corn and soybean harvesting.
The values for row-crop operations were calculated for 30-inch rows. They should be adjusted for other row widths. All values were calculated assuming efficient materials handling in the field, proper tractor ballasting to keep wheel slippage below 15 percent, properly tuned and adjusted tractor engines, and partload tractor operation efficiency by shifting up a gear and throttling the engine back.
Adapted from Fuel Required for Field Operations, PM-709
Mark Hanna, retired extension agricultural engineer, firstname.lastname@example.org