Turf normally receives 1-5 pounds of
nitrogen per 1,000 square feet per year,
and research has shown that only 5-15
percent of that nitrogen leaches as
nitrate to groundwater (4). Some nitro-
gen may also be lost as nitrogen gas (N2)
through denitrification, but most is
retained within the turf-soil ecosystem
in soil organic matter. If clippings are
removed, much applied nitrogen is lost
with the clippings, but if they are
retained, most nitrogen remains on site.
Land that has been in turf for 20 years
or more can accumulate 2,000-4,000
pounds of nitrogen per acre within its
soil organic matter (2,4).
This retention of nitrogen and other
plant nutrients represents a major envi-
ronmental benefit contributed by turf.