Submitted to: National Cotton Council Beltwide Cotton Conference
Publication Type: Proceedings
Publication Acceptance Date: 1/20/2007
Publication Date: 1/20/2007
Citation: Tewolde, H., Shankle, M.W., Sistani, K.R., Adeli, A., Rowe, D.E. 2007. Broiler Litter Improves Cotton Yield above Inorganic Fertilizers. National Cotton Council Beltwide Cotton Conference. Interpretive Summary:
Technical Abstract: Broiler litter which is a mixture of broiler chicken manure and bedding material (usually wood chips) is a complete fertilizer containing nearly all essential plant nutrients. It is generated in huge quantities in the same states where cotton is a dominant crop. Applying litter to agricultural fields as a fertilizer or soil amendment is and has been the best way of managing this important byproduct which is often viewed as a waste. But this application has been concentrated on pasture and forage crops not far from where it is generated. It has been used little on row crops including cotton. An increase in the use of litter on cotton in the region is the overall goal of this work. The specific objectives of this research were to compare the effectiveness of broiler litter against inorganic nitrogen fertilization for no-till and conventional-till cotton in an upland soil and to quantify litter benefit reduction due to lack of incorporation particularly under no-till systems. The research was conducted in 2003 to 2005 at the Mississippi Agricultural and Forest Experiment Station near Pontotoc, MS in an Atwood silt loam soil. Uncomposted broiler litter alone or litter plus inorganic N as urea ammonium nitrate solution (UAN) were tested in two unreplicated adjacent fields, one under no-till and the other under conventional-till. The treatments under each tillage included an unfertilized control, a standard fertilization that received 90 lbs/ac UAN-N plus inorganic P and K if recommended based on soil test, incorporated and none-incorporated broiler litter to supply 67% of the N need (60 lbs/ac) plus UAN to supply 33% of the N need (30 lbs/ac), incorporated and none-incorporated broiler litter to supply 100% of the N need (90 lbs/ac). The litter contained an average across years of 22% moisture, 2.5% N, 1.2% P, and 2.1% K. Fertilization with '3.5 ton/ac incorporated litter out yielded fertilization with inorganic N by approximately 14% under the no-till and by 10% under the conventional-till. Fertilization with litter ('2.3 ton/ac) plus inorganic N (30 lbs/ac UAN-N) also yielded better than the standard fertilization. Chlorophyll index measured with a chlorophyll meter usually was greater when cotton was fertilized with the standard than with litter. Visually, these differences were obvious during each season, an observation which suggests cotton fertilized with inorganic N produces the greenest plants, but this does not necessarily translate to better growth and lint yield. Lack of litter incorporation reduced yield by up to 7% under no-till but did not affect yield under conventional-till. Overall, broiler litter appears to be a better cotton fertilizer than conventional inorganic fertilizers for these soils, but lack of incorporation may reduce this benefit under no-till.