Municipal Yard Waste as a Nutrient Source for Apple Trees

Abstract

The Environmental Protection Agency has developed regulations requiring municipalities to reduce the amount of solid wastes going into landfills. One potential outlet for yard waste is agriculture. This study was conducted during the first 6 years of orchard establishment to compare tree and fruit response of `Fuji', `Golden Delicious' and `Red Delicious' apple trees to composted yard waste and other conventional fertilizers. Calcium nitrate and urea were applied at 16.8, 33.6, and 67.3 kg·ha–1 N per year. Composted municipal yard waste was applied at 1.3-, 2.5-, and 5.0-cm depths, within the sod-free strip of the tree row. Yard waste promoted growth compared to calcium nitrate and urea allowing the trees to fill their allotted space earlier. Yield and yield efficiency were generally similar across all forms of fertilizers. Foliar N was not affected by the form of nitrogen used, did not vary across the different rates of calcium nitrate and urea, and was well within the range considered sufficient (1.8% to 2.5%) for all treatments. It is concluded that the accelerated growth by yard waste was not due to N nutrition. Other foliar element levels were not consistently affected by fertilizer form or rates for the three cultivars. Fruit weight, length/diameter ratio, firmness, and soluble solids were generally not negatively affected by the yard waste, although some fruit were slightly softer and soluble solids slightly lower than fruit from trees treated with calcium nitrate and urea. This study demonstrates that municipal yard waste may provide benefits to a fertilization management system for apple orchards by promoting early growth.