Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 11/9/2005
Publication Date: 11/9/2005
Citation: Read, J.J., Sistani, K.R., Brink, G.E., Rowe, D.E., Oldham, J.L. 2005. Effects of overseeding bermudagrass with annual ryegrass on removal of excess soil nutrients from broiler litter applications [abstract]. Agronomy Abstracts. 2005 CDROM.
Technical Abstract: Broiler litter is often used as fertilizer on pasture lands in south central Mississippi. Overseeding bermudagrass with annual ryegrass appears to be an effective strategy for remediation of manure-impacted soils, particularly excess phosphorus (P). This research determined the fate of broiler litter nutrients in a Ruston soil. Whole plots of bermudagrass (4 x 6 m), which in previous three years were provided 0, 4.5, 9, 18, and 36 Mg/ha litter, were split and each half was sown to annual ryegrass in fall 2001, 2002, and 2003. Plots were fertilized with mineral nitrogen (N) following each bermudagrass harvest. Results for surface soils, 0-5 cm depth, indicated total N and plant available P and K (Mehlich 3 extractant) increased linearly as litter rate increased. In treatments that provided less than 36 Mg/ha litter, soil P was lower in bermudagrass-ryegrass than bermudagrass, although the two forage systems did not differ in ‘drawdown’ rate. The largest change in soil was observed at 36 Mg/ha litter, presumably from the removal of high biomass due to increased soil fertility. Because bermudagrass-ryegrass removed more P, but did not have faster drawdown of soil P than bermudagrass, the benefits of overseeding pastures with annual ryegrass were associated more with additional hay production and removal of nutrients than with a reduction in soil P levels.