RESPONSE OF KENTUCKY-31 TALL FESCUE TO BROILER LITTER AND COMPOSTS MADE FROM BROILER LITTER

Recycled paper treated with boric acid (BA) is gaining acceptance as b edding in broiler houses. Applying this litter to Kentucky 31 (K-31) t all fescue, Festuca Arundinacea Shreb, pastures raises the issue of po tential boron (B) toxicity. There is also the question of nitrogen (N) availability from composts made with berated paper and broiler manure . The effect of five N sources at 224, 448, and 896 kg N/ha in a facto rial arrangement plus an unfertilized control and high nitrogen-phosph orus-potassium (NPK) + additional boron at 45 kg B/ha on growth and NP KB uptake of K-31 tall fescue was determined in a greenhouse during th e spring of 1992. The five N sources were (1) inorganic salts, (2) com post made from hen manure, broiler manure, fescue hay and bark (M1), ( 3) fresh broiler litter (M2), (4) compost made from broiler manure and berated paper bedding (M3), (5) compost from hen manure, oak leaves, broiler litter(M4). The soil was Cecil sandy clay loam subsoil. Six ha rvests were made at 4-cm cutting heights for determination of dry matt er, N, P, K, and B uptake in tops, stubble, roots, and residue. Relati ve yield response of M2 was 65% of that from inorganic NPK, whereas th e yield of the three composts was 22-30% of that from inorganic NPK. O ver 50% of the N applied in compost residue remained at the soil surfa ce. Boron toxicity to K-31 as estimated from yield reduction or from v isual symptoms did not occur from 20 kg B/ha in compost made with bera ted paper(M3). However, a 12% yield reduction did occur at the 45 kg B /ha rate from inorganic B. Industry efforts to reduce the amount of bo ric acid used in the treatment of recycled paper, the high mobility of B in humid areas, the apparent ability of K-31 tall fescue to tolerat e massive quantities of compost and high rates of B application sugges t that the application of the broiler litter from houses where BA-trea ted recycled paper is used as bedding would be environmentally safe at application rates based on N requirements of K-31 tall fescue.