Applied Turfgrass Science最新文献

Humates and Humic Substances are found in nature and are components of soil humus. Humates function in a wide variety of natural soil processes including chelating of metals, stimulation of soil microbial activity, degradation of organic matter. It has been demonstrated to have soil amending characteristic.

Humic Dispersible Granules (DG) contains four main elements of humate products, HAP, Humic Acid, Fulvic Acid and Humin. All have valuable functions as soil amendments. Humic acid not only stimulates soil microbial activity and is thought to act as catalyst for soil enzymatic activity. It is thought to be essential for plant nutrient in soils. Fulvic acid is a strong chelating agent that can strip metals from salt ions and are especially active stimulating soil microbes when in the presence of a supply of nitrogen.

Humic products available as soil amendments for root zone construction vary in quality and difficulty of use in practice. Humic DG will be examined as a novel form of Humate, beneficial to low CEC soils and in use. Its mode of activity allows Humic substances to self incorporate into soil on application. This is accomplished through patented dispersing technology creating thousands of sub-particles. The dispersed sub particles providing more surface area for Humates to decompose into Humic substance to be available to plant s in these low organic soils.

Constructed root zones provide unique challenges for plant growth in that we often desire to grow species of plants not suited for the conditions of the constructed rootzone. Plant roots evolved to maximize the survival of plants growing in natural soils and often respond in less than desirable ways when grown on constructed rootzones leading to reduced root growth, increased need for foliar fertilization and increased invasion of undesirable species. Nutrient and water availability in sand based rootzones is often limiting requiring frequent applications of both supplemental irrigation and fertilizers. Frequent fertilization events often are applied as foliar fertilizers and there is evidence that this may lead to less desirable shallower rooted species such as annual bluegrass to become more competitive. In addition frequent watering to provide consistent playing conditions on golf course putting greens has created an environment that favors invasive species without roots, leading to an increase in silvery thread moss invasion. The constructed rootzones also may create different nutrient cycling issues within the rootzone that may inhibit the adoption of more environmentally friendly lower impact grasses such as velvet bentgrass by influencing the form of nitrogen available in the rootzone. The inclusion of certain nutritional amendments into the rootzone such as phosphorus bounded to alumina can alter root growth, encouraging deeper root growth. When developing and evaluating constructed rootzones, it is important to evaluate how the management of plants on that root zone may lead to a less competitive environment for the desired species.

To develop a national golf course environmental profile, a survey was sent to 16,194 superintendents at US golf facilities to determine pesticide storage and mixing and loading practices; use of written pesticide emergency plans, integrated pest management plans, and pesticide application plans; restrictions to pesticide operations; number of certified pesticide applicators; pest management tactics; trends in pesticide use; and pesticide use. The response rate was 20.5%. Analysis of data indicated responses were received from a representative sample of golf facilities in the US with the exception of facility type. Data were weighted for facility type. Almost all golf facilities had at least one certified pesticide applicator on staff. Superintendents used multiple tactics to manage pests, and they used these tactics on a routine basis. Data from pesticide use records did not accurately reflect the active ingredients used on specific components of the golf course (greens, tees, fairways, rough). Results from the pest management tactics provide a baseline for comparison with results from future surveys to monitor industry change over time.

Physical water conditioning products have been used on golf courses to improve turfgrass quality, improve rootzone salinity, and to reduce irrigation water use. A four-year study was conducted at New Mexico State University to investigate the effects of non-chemical in-line water conditioners (two catalytic, one magnetic, one hydro-electric, and a control treatment) on turfgrass establishment, and on turfgrass quality and rootzone salinity of a perennial ryegrass stand. Conditioning treatments were applied under potable [Electrical conductivity (EC) = 0.6 dS/m] and saline (EC = 3.1 dS/m) irrigation. Conditioning treatments did not affect perennial ryegrass establishment, only saline irrigation delayed establishment. Turfgrass quality on control plots did not differ from conditioner treated plots for both water qualities on all but one sampling date. The rootzone salinity results were inconclusive; no clear consistent trends were found for individual measured parameters. After four years of research, a consistent positive impact of these conditioning units on turf quality and rootzone salinity could not be substantiated.