past few years. Yard waste compost includes grass clippings, leaves from trees and shrubs, woody branches, and other materials that are the result of yard trimmings ( Ozores-Hampton et al., 1999 ). Facilities designed to process YWC have become more
Courtney D. DeKalb, Brian A. Kahn, Bruce L. Dunn, Mark E. Payton and Allen V. Barker
Bob Ebel, David G. Himelrick, Arnold Caylor and Bryan Wilkins
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.
Dennis B. McConnell and Wayne H. Smith
Three foliage plants, Dracaena fragrans, Peperomia obtusifolia and Schefflera arboricola were grown in 24 different mixes. Potting mixes were formulated using yard waste compost from two sources, a commercial mix (Metro 300) and a prepared mix (peat: pine bark sand). All potting mixes produced acceptable plants with no phytotoxicity associated with any mix. Only minor differences were discerned in the growth rate of P. obtusifolia and S. arboricola.
The growth rate of D. fragrans showed the greatest response to potting mix formulations. Plants in a standard potting mix (P/PB/S) used in the industry for D. fragrans grew slower than plants in many of the mixes containing various fractions of yard waste compost. Chemical and physical properties of the potting mixes used showed physical properties had the greatest variability. Overall, the best growth for all 3 plants was in a potting mix composed of 87.5% Metro 300/12. 5% YWC#1 and worst growth was in YWC#2 (100% composted (live oak leaves).
Michael S. Harrell and Grady L. Miller
The benefits of composted yard waste applied as a mulch were demonstrated in a field study at two locations and supporting greenhouse research. Compost was applied to eroded roadside slopes of about 12° and 27° to determine the influence on soil displacement and establishment and/or enhancement of permanent roadside vegetation. Treatments consisted of compost rates of 5 cm and planted with asiastic jasmine (Trachelopermum asiaticum), 5 and 10 cm, seeded with 110 or 220 kg·ha–1 80:20 bahiagrass (Paspalum notatum Flugge): bermudagrass (Cynodon dactylon L.) seed mix by weight, straw erosion control mats, and bahiagrass sod. Compost treatments effectively controlled soil displacement regardless of compost rate or seeding with turfgrass at both locations. Effects on roadside vegetation and visual quality varied with location. Asiatic jasmine did not establish at either site. Compost mulch applications increased total vegetation, turfgrass density, and quality at the site with 27° slope and 4% initial soil organic matter content, but resulted in a decline in cover at the site with a 12° slope and <1% organic matter content. Compost mulch can effectively prevent soil displacement from roadside slopes, but may not promote establishment or enhancement of permanent vegetative cover.
Brian A. Kahn, Niels O. Maness, Donna R. Chrz and Lynda K. Carrier
carotenoids, and total glucosinolates in pak choi tissues. The work reported here was part of a larger study designed to compare two unblended organic materials—spent mushroom substrate (SMS) and yard waste compost (YWC), both hereafter referred to as composts
R.C. Funt and A.K. Hummell
Compost increases nutrient availability, cation exchange capacity, and micronutrients in the soil. In urban areas, yard waste consisting of grass clippings, leaves, and woody materials can be composted. The purpose of this study was to compare the effects of soil-composted municipal sludge and soil-composted yard waste mixtures on strawberry plants grown in the greenhouse. Earliglow strawberry plants were planted in pots containing a soil mix of 0%, 10%, 20%, or 40% by volume of composted municipal sludge or composted yard waste. Plants were grown in the greenhouse with supplemental lighting. Soil-compost mixes having greater the 90 mhos of soluble salts were detrimental to the plants; plant survival was reduced by 80% in the 40% composted sludge–soil mix within 2 weeks after transplanting. Plants survived and grew in all other treatments. Composted yard waste at 20% to 40% by volume increased leaf K and B, but decreased P, Ca, and Mg.
Sandra A. Balch, Dick L. Auld and Richard E. Durham
The objective of this study was to assess the feasibility of utilizing composted municipal yard waste as a component of potting media, which is predominantly composed of peatmoss, a nonrenewable and increasingly expensive medium. Green Comet broccoli (Brassica oleracea L. Italica group) was grown in five ratios (1:0, 1:2, 1:3, and 0:1) of composted yard waste: commercial soilless potting medium. Plant heights were recorded weekly. At the end of 6 weeks, measurements were taken on plant height, fresh weight, dry weight, and root: shoot ratios. Media leachate was tested for pH and soluble salt levels. Germination tests were run using the same potting mix ratios. Percent germination and seedling survivability were recorded. Results show that yard waste compost can be used as a component of potting media, although seed germination and seedling growth are inhibited at high compost levels.
Composted yard waste (CYW) soil applications at rates from 0 to 224 t·ha–1 and with or without preplant fertilizer were evaluated over a 3 years. In year 1, the applications were made in early March, with a succession of crops grown continuously until year 2. During year 2 the entire area was kept as clean fallow, but plot integrity was maintained. Soil samples were taken periodically for chemical analysis. In late March of year 3, a second application of CYW was overlaid on one half of each previously treated plot, and pole beans were grown. Nitrogen tie-up occurred only with the 224 t·ha–1 when no fertilizer was added during year 1 for all crops studied. Where fertilizer was added, no visual symptoms of deficiency occurred with any of the crops; however, with some crops, yields were reduced. CYW application in year 3 resulted in visual symptoms of N deficiency (extreme leaf yellowing) in pole beans along with yield reduction even when fertilizer was added. This was the result of immature CYW used in that year. CYW degradation occurred during the fallow period in year 2, as shown by decreasing organic matter levels in the soil. During year 3, pole bean yields were ≈4% higher where intermediate to high levels of CYW rates were used during year 1 but no additional during year 3 compared to the control plots. In general, CYW for vegetable production was useful when sufficient fertilizer was used to overcome the high initial C:N ratio.
William E. Knoop and Phillip F. Colbaugh
An urban educational program titled “Don't Bag It” having as its' goal the reduction of the solid waste flow to landfills, was initiated in Ft. Worth the spring of 1988. The program, using media methods and volunteer demonstrators, teaches homeowners how to manage lawns without bagging grass clippings.
Very favorable program results have encouraged the spread of the program to 25 other Texas cities and the distribution of the program across the country:
Henry G. Taber and D.F. Cox
Three trials, beginning June, July, and September 1991, examined the breakdown of photodegradable plastic bags. The plastic contained a light-sensitive compound dissolved in the polymer to hasten degradation. The bags were placed in east-west rows on bare ground. Other factors studied included turning the bags over either every 3 or 7 days and either filling the bags with fresh grass clippings or leaving them empty. Strength loss was determined with a hand-held puncture tester. Strength increased initially by 36%, 32%, and 63% in the three trials, respectively. The bags took 33, 35, and 64 days to reach brittleness (puncture strength of 180 g) in the three trials, respectively. Once degradation began, all trials showed similar rates of decline. However, the degradation began 7 days after exposure in the first two trials, but not until 14 days after exposure in the September trial. The addition of grass clippings to the bags increased the initial strength and delayed the onset of degradation. Turning the bags every 3 days rather than every 7 did not affect degradation.