Donald Vietor, Clyde Munster, Tony Provin, Richard White, David Chalmers, and Ronnie Schnell. Soil and Crop Sciences, Texas A&M University, 2474 TAMU, 370 Olsen Blvd, College Station, TX 77843-2474
An NRCS CIG project demonstrated manure
and wastewater cycling through tufgrass sod on three Texas watersheds. Composted
dairy manure (CDM) was topdressed at a total P rate
of 124 kg ha-1 on TifSport bermudagrass on the Leon River Watershed. On the Brazos River
Watershed, topdressed poultry litter (PL) supplied 82 kg total P ha-1 for regrowth
of Tifway bermudagrass.
A joint venture in Zoysiagrass production between Stoney Point Feedyard and TriTex Grass on the Trinity River Watershed provided the
third demonstration. Topdressing of CDM on TifSport
sod increased soil organic C concentration 44% and gravimetric water content
25% compared to controls. In addition, total soil N concentration was 49%
greater and total P concentration was 64% greater with than without CDM.
Similarly, CDM increased TifSport tissue
concentrations 12% for total N and 120% for total P. At TifSport
harvest, 95% of total P and 66% of the total N top-dressed in CDM were exported
with sod. Topdressing of PL on Tifway sod fields
within the Brazos River Watershed increased both soil organic C concentration
and gravimetric soil water content 31% compared to the control. Turf coverage
rate was greater, total N concentration was 32% greater in soil and 34% greater
in turfgrass, and total P concentration was 53%
greater in soil and 130% greater in turfgrass for Tifway topdressed with PL than the
control. Increased soil P concentration after topdressing of PL increased
dissolved P (DP) concentrations in runoff (3.6 mg L-1) compared to the
Tifway control. On the Trinity River Watershed, DP
concentrations in runoff of simulated rain from Zoysiagrass
turf were 3.5 mg L-1 after manure incorporation and wastewater
application. Cycling of CDM, PL, and feedyard manure
and wastewater benefits sod production, but rate and method of application and
runoff need to be managed to protect water quality.