ECONOMIC AND ENVIRONMENTAL IMPLICATIONS OF SMALL GRAIN PRODUCTION AND USE ON PENNSYLVANIA DAIRY FARMS

Abstract

Two challenges facing dairy producers are low profit and environmental issues related to nutrient management.Wholefarm simulation was used to determine if adding small grain crops to traditional corn and alfalfa rotations providedlongterm environmental and economic benefits. Small grain cropping strategies included 1) corn double cropped with barleyharvested as cash crop grain and straw bedding, 2) corn double cropped with barley harvested as feed grain and straw, 3) corndouble cropped with barley harvested as silage, 4) corn double cropped with rye harvested as silage, and 5) corn replacedwith cash crop wheat and straw bedding. Nitrogen leaching loss over the farm was reduced by 10 kg/ha (8.9 lb/acre) when40% of the corn was double cropped with a small grain, and soil P accumulation was reduced by 2 kg/ha (1.8 lb/acre) peryear. Annual farm net return or profit was increased by up to $93/cow when doublecropped barley or singlecropped wheatwas harvested as grain and straw, by about $30/cow for doublecropped barley silage, and $50/cow for doublecropped ryesilage. Use of small grains generally reduced the risk or yeartoyear variation in net return. The economic benefit of usingsmall grains was not sensitive to farm size, herd milk production level, the amount of forage used in animal rations, or grainprices, but there was less benefit when the farm was moved to a more northern climate. If straw was not harvested and usedfor bedding, the economic benefit for producing grain as a cash crop or feed was eliminated. Use of small grain crops onPennsylvania dairy farms should be encouraged, particularly when double cropped with corn, to reduce N leaching loss,reduce soil P accumulation, and improve farm profit.