Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 6/8/1999
Publication Date: N/A
Technical Abstract: A rapid method is needed for estimating the quantity of soil N that is potentially mineralizable during a growing season, especially in soils with previous manure applications. Our objectives were to compare results of a rapid laboratory procedure with (1) long-term soil N mineralization in the lab and (2) N uptake from dairy cattle (Bos taurus) manure by Coastal' bermudagrass [Cynodon dactylon (L.) Pers.] in a field study. The rapid procedure involved quantifying CO2 evolved for 24 h following the rewetting of dried soil. Manure was applied annually at rates of 0, 112, 224, and 448 kg N/ha to Windthorst fine sandy loam from 1992 through 1996. Results of the rapid mineralization procedure were very highly correlated with long-term soil N mineralization from samples collected in 1995 and 1996 and forage N uptake for the two years. We recommend this procedure for further evaluation for the rapid assessment of soil N mineralization and crop N uptake.