Orchardgrass response to different types, rates and application patterns of dairy manure

Abstract

Manure management is a difficult task on many intensive dairy farms. Crops that can utilize large quantities of manure N, yield quality forage with larger rates of manure application, and allow manure spreading at different times in a year can simplify that task. A study was conducted in 1990 and 1991 on a Copake sandy loam soil (mixed mesic) in New Milford, Connecticut. The objectives were: (1) to measure and compare dry matter (DM) response of orchardgrass ( Dactylis glomerata L.) to different amounts and application times of N fertilizer and liquid and solid cattle manure; and (2) to determine crop uptake of fertilizer and manure N. Fertilizer and liquid and solid manure were applied to the soil surface annually in amounts of 150, 300 or 450 kg N ha −1 in one, two or four equal applications. Orchardgrass dry matter production increased over the entire range of N amounts from all sources. Yields varied from approximately 2500 kg DM ha −1 for control plots (0 kg N) to 10600 kg for plots receiving 450 kg N ha −1 either as fertilizer or liquid manure. Crop response to liquid manure application was greater in year one with abundant rainfall than in year two with dry conditions during most of the growing season, whereas crop response to solid manure application improved in the second year, due to the availability of residual organic N. Orchardgrass was more sensitive to the timing of fertilizer N application than to manure N application. Despite the large differences in weather patterns experienced during this study, analysis of application patterns indicated that manure could be applied throughout the growing season to crop stubble (post-harvest) with comparable rates of uptake overall. N uptake in control plots averaged 56 kg N ha −1 for both years, compared to 340 kg N ha −1 for fertilizer plots, 250 kg N ha −1 for liquid manure plots and 190 kg N ha −1 for solid manure plots receiving 450 kg total N ha −1.