IMPLICATIONS OF LONG-TERM LAND APPLICATION OF POULTRY LITTER ON TALL FESCUE PASTURES

Alabama's Poultry industry is most heavily concentrated in the Sand Mo untain region of northern Alabama. Disposal of litter (manure and bedd ing material) generated from poultry production in the region is typic ally accomplished by land-spreading onto tall fescue (Festuca arundina cea Schreb.) pastures. We conducted a study in four major poultry prod ucing counties in the Sand Mountain region to determine the effects of long-term litter use on soil and plant conditions related to pasture production and forage quality. Soil samples from 0 to 6 in. depth and plant tissue samples were collected from tall fescue pastures receivin g annual applications of litter for 15 to 28 yr (littered) or not rece iving such applications (nonlittered). These samples were analyzed for soil pH and organic matter, plant nitrate-N, soil and plant total N, and extractable P, K, Ca, Mg, Cu, Fe, Mn, and Zn. Results point to hig her soil pH, soil organic matter, and total N in soils receiving long- term litter applications. Extractable soil P, K, Ca, Mg, Cu, and Zn we re higher in littered than in nonlittered pastures. Tissue analysis sh owed that litter applications increased forage concentrations of N, ni trate-N, P, K, Ca, Mg, Fe, and Cu as compared with forage from nonlitt ered pastures. The ratio K/(Ca + Mg) in plant tissue, associated with grass tetany potential, was higher in littered than in nonlittered pas tures, but did not exceed the commonly accepted threshold value of 2.2 . Our findings indicate that long-term poultry litter application to t all fescue pastures has caused an accumulation of nutrients in soils a nd plants, but there was no evidence that this accumulation has create d a forage quality problem.