Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: June 26, 1996
Publication Date: N/A
Technical Abstract: Nitrogen availability may limit crop growth in semi-arid regions when CRP land is returned to production. No-till, sweep till, and moldboard plow were compared for effects on N mineralization following conversion of CRP to wheat production. NO3 and NH4 were measured during the eight-month fallow period following initiation of the tillage treatments. Low rainfall and soil moisture during the initial two-month period resulted in NH4 accumulation. Nitrification increased following rains in May and June. Overall, total N mineralized during the fallow period was less than 10 kg ha-1. Low N availability without additional N fertilization reduced early wheat growth. The low rates of N mineralization and nitrification indicate that CRP land will require substantial N inputs. Producers will need to reduce vegetation and begin tillage activities early to gain the greatest benefits for water and N availability.