Published in Agronomy Journal, Volume 75, July 1, 1983, pages
654-656. Publisher website: http://www.agronomy.org NOTE: At the
time of publication, the author David J. Wehner was affiliated
with the University of Illinois at Urbana-Champaign. Currently,
April 2008, he is the Dean of the College of Agriculture, Food
and Environmental Sciences at California Polytechnic State
University - San Luis Obispo. The components of a turfgrass
ecosystem, including plants, an intervening layer of thatch and
the underlying soil, influence the fate of topically applied
urea fertilizer. The loss of urea N by ammonia volatilization
may be governed by the rate of urea hydrolysis. The main
objective of this study was to determine the extent of urease
activity associated with turfgrass plant tissue, thatch, and the
underlying soil. This information may help elucidate the
mechanism of ammonia loss following urea application. Because a
turfgrass stand frequently possesses an extensive thatch layer
that may serve as the primary pla