EFFECTS OF LIQUID HOG MANURE APPLICATION RATES ON SILAGE CORN YIELD AND NUTRIENT UPTAKE
The objective of this work was to determine the response of corn to liquid hog manure surface applied at rates of 28, 56 and 112 tonnes/ha. In greenhouse trials, yield of corn grown for 4 wk on St. Jude loamy sand was not affected by manure application. On Kamouraska silty clay, only manure applied at a rate of 112 tonnes/ha increased corn yield, as compared to the non-treated control. Corn response on Janvier sandy clay loam improved with increasing rate of manure application up to 56 tonnes/ha. Application of 112 tonnes/ha (325 kg N/ha) manure increased N content of corn and had a significant residual effect as noted by the high yield obtained at the second harvest. In a 2-yr field experiment on Kamouraska soil, corn yield was significantly higher at 112 tonnes/ha (avg 432 kg N/ha) than chemical fertilizer application at 150 kg N/ha, and manure-treated soil contained more P, Ca and Mg after the first year. Nutrient uptake by corn increased with amount of manure applied. However, corn whole plant composition was not affected by rate of manure application. N recovery was higher from manure at 28 or 56 tonnes/ha than from a chemical fertilizer (150 kg N/ha, 65.5 kg P/ha and 125 kg K/ha). At the rates applied, the liquid hog manure did not result in reduced corn yield.Key words: Corn yield, hog manure, nutrient uptake, silage corn