Economic and environmental implications of small grain production and use on Pennsylvania dairy farms

Two challenges facing dairy producers are low profit and environmental issues related to nutrient management. Whole-farm simulation was used to determine if adding small grain crops to traditional corn and alfalfa rotations provided long-term environmental and economic benefits. Small grain cropping strategies included 1) corn double cropped with barley harvested as cash crop grain and straw bedding, 2) corn double cropped with barley harvested as feed grain and straw, 3) corn double cropped with barley harvested as silage, 4) corn double cropped with rye harvested as silage, and 5) corn replaced with cash crop wheat and straw bedding. Nitrogen leaching loss over the farm was reduced by 10 kg/ha (8.9 lb/acre) when 40% of the corn was double cropped with a small grain, and soil P accumulation was reduced by 2 kg/ha (1.8 lb/acre) per year. Annual farm net return or profit was increased by up to $93/cow when double-cropped barley or single-cropped wheat was harvested as grain and straw, by about $30/cow for double-cropped barley silage, and $50/cow for double-cropped rye silage. Use of small grains generally reduced the risk or year-to-year variation in net return. The economic benefit of using small grains was not sensitive to farm size, herd milk production level, the amount of forage used in animal rations, or grain prices, but there was less benefit when the farm was moved to a more northern climate. If straw was not harvested and used for bedding, the economic benefit for producing grain as a cash crop or feed was eliminated. Use of small grain crops on Pennsylvania dairy farms should be encouraged, particularly when double cropped with corn, to reduce N leaching loss, reduce soil P accumulation, and improve farm profit.