A recent stretch of mild weather might have some farmers eager to get an early start on spring planting, but a Purdue University agronomist is urging patience to give the soil time to dry sufficiently. “There is no reason to rush out and do spring tillage in March if the goal is to plant corn in mid-April or to plant soybeans in late April or early May,” said Tony Vyn, a cropping systems specialist. “Soil compaction from tractors and tillage implements that went out into marginal soil conditions during the prolonged wet spring of 2015 extracted a yield penalty from corn and soybeans.” Compaction occurs when soil particles are pressed tightly together under heavy loads. The compressed particles are less able to absorb moisture and nutrients, increasing the risk of erosion and runoff and making it more difficult for plants to develop healthy root systems. The risk of compaction is greatest when the soil is wet. The risk of poor root development is greatest when wet conditions are followed by a dry period.
Last year’s rainy spring delayed planting in many parts of the Midwest, and compaction became a concern in some areas when farmers started scouting and tilling in fields that were still wet. Vyn said soil conditions are likely to be better this spring compared with 2015 because many farmers took advantage of unusually warm, dry weather to till their fields last fall. Fall tillage allows the soil to dry faster and reduces the risk of compaction or rutting come spring. Vyn said he was pleased that more farmers last fall chose to use strip-till, a less invasive method of field preparation where only the soil in the seedbed is disturbed. The soil between the rows remains protected by crop residue, providing some of the same conservation benefits as a no-till operation. Strip-till can reduce or even eliminate the need for spring pre-plant tillage, he said.
For farmers planning spring field operations, Vyn recommends keeping a close watch on local soil and weather conditions before rolling out the heavy equipment. “We still have several weeks before crops have to go into the ground,” he said. “There is no need to jump the gun if conditions are not ideal.” The Indiana State Climate Office, based at Purdue, forecasts warmer-than-normal temperatures for the remainder of this spring, with equal chances for above-, below- or normal precipitation.