specific environment into which they are planted. Normal undisturbed soils have established horizons, ample pore space and organic matter, beneficial organisms, and soil aggregates that allow air, water, and nutrients to penetrate ( Perry, 1982 ). Urban
Julie Guckenberger Price, Amy N. Wright, Kenneth M. Tilt, and Robert L. Boyd
Julie Guckenberger Price, Amy N. Wright, Robert S. Boyd, and Kenneth M. Tilt
determine the effect of planting technique, organic matter selection with above-grade planting, and planting season on post-transplant growth of two native landscape shrubs selected for their reportedly different landscape establishment success rates ( Dirr
John M. Kauffman, John C. Sorochan, and Dean A. Kopsell
Organic matter accumulation near the soil surface of putting greens is of concern to turf managers because of its effects on soil physical properties that can influence turf performance. Soil OM is composed primarily of dead and sloughed plant
Virginia I. Lohr and Caroline H. Pearson-Mims
The effect of organic matter addition and irrigation rates on the growth of bedding plants was found to vary with species. Marigold and sweet alyssum were field-grown with or without added peat moss under normal or 50 percent reduced irrigation.
Regardless of organic matter treatment, marigolds with reduced irrigation were shorter than those with normal irrigation. Under normal irrigation, adding organic matter had no effect on height. Under reduced irrigation, incorporating organic matter was beneficial to marigolds: plants in these plots were 10% taller than plants under reduced irrigation without added organic matter.
Sweet alyssum, a relatively drought-tolerant plant, was wider under reduced than under normal irrigation. It did not benefit from added organic matter: plants grown with added organic matter were 17% narrower than those without added organic matter, regardless of irrigation level. Blanket recommendations to add organic matter to conserve water should be avoided.
Dario Stefanelli*, Giovambattista Sorrenti, and Ronald L. Perry
Soil organic matter is a critical component which is fundamental in plant growth. Several soil factors are influenced by organic matter such as slow release of nutrients, increased water holding capacity, improved soil physical characteristics and improved environment for soil microorganisms. The aim of this work is to investigate the physical effect of organic matter content in the soil on apple root growth and development. Twenty five two-year old apple trees (Malus domestica, Borkh) cv. `Buckeye Gala' on M.9 NAKB 337 rootstock were planted in completely transparent acrylic boxes. Plants have been grown in a green house to avoid external rain in a complete randomized design. Trees were planted in a sandy-mix soil amended with soil high in organic matter, “muck”, at four incremental levels. Treatments compared were a control (sandy soil with 0% organic matter) and 1%, 2%, 4% and 8% soil organic matter. The amount of water applied by automatic drip irrigation was comparable for all the treatments to avoid high fluctuation of soil moisture on root dynamics. All treatments have been fertilized with the same amount of mineral fertilizer to avoid the nutrition effect on root dynamics. Digital photos of roots were taken to study their dynamics every one to two weeks during a period of five months. Roots have been highlighted with Photoshop and then analyzed with WinRhizo to measure root length, area, lifespan and dynamics. At the end of the growing period plants have been harvested and fresh and dry weight was evaluated to asses the root/shoot ratio. The effects of the treatments on root length, area, lifespan and dynamics, and root/shoot ratio will be discussed.
Nanik Setyowati and Leslie A. Weston
Dithiopyr (Dimension, Monsanto) is a turfgrass herbicide currently under evaluation for use in ornamentals. Granular herbicide depth and seed placement were evaluated in greenhouse studies with tolerant or susceptible weeds. Dithiopyr was applied preemergence to weeds at the rate of 2.24 kg/ha to Maury silt loam soil. Weed seeds were planted routinely at 0.64 cm depth. Dithiopyr placed at the soil surface or 0.64 cm in depth caused the greatest injury to seedlings, followed by dithiopyr at 1.28 cm depth. Dithiopyr at 2.54 and 3.81 cm below the surface had no effect upon seedling growth. When seeding depth was investigated, seed placed at 0.64, 1.28 or 1.91 cm below the surface showed greatest seedling injury when dithiopyr was routinely applied at 0.64 cm depth. Seed placement on the soil surface resulted in the least injury to weeds.
Peat moss was added to Maury silt loam soil and to sand to investigate the influence of organic matter upon activity. Soil with 2% peat resulted in the least injury to selected weed seedlings while sand, and sand plus up to 3% peat showed greatest injury. Sand amended with 5 and 6% peat also resulted in less injury to weed seedlings. Ivy leaf morningglory and KY 31 fescue were most tolerant of dithiopyr while barnyardgrass and large crabgrass were most sensitive. Dithiopyr uptake, translocation and metabolism studies will be conducted with susceptible and tolerant weed and woody ornamental species.
James M. Spiers
The effect of incorporated sphagnum peatmoss and minimal fertilization on the establishment and subsequent growth of rabbiteye blueberries (Vaccinium ashei Reade) was determined in 4 field studies conducted on typical fine sandy loam, upland mineral soils in south Mississippi. Incorporated peatmoss increased plant vigor, plant height, shoot weight, leaf chlorophyll level, and fruit yield and reduced chlorosis symptoms. First- and second-year plant growth and second-year fruit yields were reduced by either slow-release or fast-release granulated fertilizer. Soluble fertilizers produced less plant damage than granulated fertilizers but no more plant growth than no fertilization. There was a close association between over-fertilization and cholorosis symptoms.
Sudeep S. Sidhu, Qingguo Huang, Robert N. Carrow, and Paul L. Raymer
Formation of thatch and mat layers is one of the major problems in management of modern turfgrass golf greens. Thatch is a layer of organic matter that accumulates between the soil and green turfgrass and contains both living and dead plant tissues
Carl J. Rosen and Deborah L. Allan
reported in the scientific literature. Soil properties The beneficial effects of organic matter on soil physical, chemical, and biological properties have been known for many years. Maintaining or increasing soil organic matter levels can improve
Adam Montri and J.A. Biernbaum
removal of existing groundcover, reduction of the weed seed bank, increasing soil organic matter (SOM) and fertility, and if necessary, grading and adjusting the slope for rain water removal. It is recommended that site and soil preparation begin 1 year or