Sulfur-Coated Urea and Uncoated Soluble Nitrogen Fertilizers for Fescue Forage
1969
Mays, D. A. | Terman, G. L.
Field experiments were carried out during 1965–67 to compare rates, sources and times of N topdressing for ‘Kentucky 31’ fescue (Festuca arundinacea). Uncoated ammonium nitrate (AN), urea, and other readily soluble N fertilizers resulted in higher first-cutting yields, which were higher in content of total N. Sulfur-coated urea (SCU) resulted in lower first-cutting and higher later-cutting yields than did the soluble N sources. Total annual yields were usually similar with all N sources. Mixtures of AN and SCU or split applications of AN resulted in the most uniform seasonal growth and N content. Lower yields and apparent crop recovery of N from uncoated urea and urea ammonium phosphate (UAP) indicated lower efficiency of these urea-containing N sources for topdressing, particularly at higher N rates. December, January, February, and March topdressing dates had rather similar effects on forage yields and N contents.
显示更多 [+] 显示较少 [-]