at the Conservation and Production Research Laboratory, Bushland, TX, September 1, 1999 : "improving nutrient and water use efficiency in crop production" Bushland Summer Crops Field Day (1999 : Bushland, Texas, USA) creator United States Agricultural Research Service. Conservation and Production Research Laboratory text series technical report conference publication us Bushland, TX USDA 1999? 1999 1999 continuing eng 43 p. (loose-leaf) a joint report by Conservation & Production Research Laboratory, Agricultural Research Service, USDA Field crops Congresses Crops Congresses United States. Agricultural Research Service. 030818 20260817161250.0