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Common bermudagrass (Cynodon dactylon) and hybrid bermudagrass (Cynodon dactylon var. dactylon × C. transvaalensis) often are used for athletic fields as a result of their wear tolerance and recuperative ability. A wear tolerance study was conducted May 2007 through Nov. 2008 in Lexington, KY. Plots were managed as athletic turf and simulated traffic was applied during the Kentucky high school football seasons. The cultivars Quickstand, Tifway 419, Riviera, and Yukon grown in a sand-based medium were evaluated. Trinexapac-ethyl (TE) was applied at label rates and frequencies or left untreated. Overseeding treatments were perennial ryegrass (Lolium perenne) at 0, 546, and 1093 lb/acre pure live seed. Traffic treatments were applied with a Brinkman traffic simulator three times per week, once each Monday, Wednesday, and Friday, without regard to soil moisture status or weather for the periods 10 Sept. to 2 Nov. 2007 and 12 Sept. to 14 Nov. 2008. In both years of the study, the main effect of cultivar was significant (P < 0.05) in traffic tolerance (‘Tifway 419’ = ‘Riviera’ > ‘Quickstand’ = ‘Yukon’). Overseeding at the medium and high rates also provided significantly greater turf cover for the coarse-textured, more open cultivars (Quickstand and Yukon) over the fine-textured, more dense cultivars (Riviera and Tifway 419). Applications of TE did not significantly improve tolerance to simulated athletic traffic in either year of the study regardless of cultivar or overseeding treatment. Within the parameters of this study, data indicate that only cultivar has significant effects on tolerance to simulated traffic on a sand-based field. Overseeding treatments for the fine-textured, more dense cultivars and TE applications on sand-based field systems had no positive significant effects on tolerance to simulated traffic.

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The use of seeded bermudagrasses (Cynodon dactylon) is increasing as athletic field and golf course turf. Anecdotal evidence indicates probable and important differences in germination rates among cultivars when established in late spring or early summer. Germination studies were completed in May 2011 in the Turfgrass Science Laboratory at the University of Kentucky on 19 commercially available seeded bermudagrass cultivars. Evaluations for germination rate and total germination under varying temperature regimes representing 20-year average day/night temperatures for seeding times from 15 May to 1 Aug. were conducted to quantify any differences in germination characteristics among cultivars as affected by temperature. There were highly significant differences (P < 0.0001) among cultivars in germination rate and total germination when grown under 20-year average day/night temperatures. The cultivars Casino Royale and Riviera consistently represented the fastest/slowest to germinate and highest/lowest total seeds germinated across all temperature regimes, respectively. Significant differences (P < 0.0001) were also observed within cultivars for total germination across the temperature regimes tested. The average temperatures of 15 May and 1 Aug. represented slowest/fastest to germinate and lowest/highest total seeds germinated across all temperature regimes, respectively.

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Use of seeded-bermudagrasses (Cynondon dactylon) is expanding rapidly, especially on high-use athletic fields. Previous work has defined significant differences in several parameters among cultivars. Experiments were conducted in Lexington, KY, in 2004 and 2005 to test the tolerance of the cultivars Riviera, Princess, Transcontinental, Savannah, Yukon, and the experimental line SWI 1012, with and without applications of trinexapac-ethyl to simulated athletic traffic. Plots were established in June of each year and managed as athletic field turf. Simulated traffic was applied using a Brinkman traffic simulator during high school football seasons in Kentucky at a level roughly equivalent to three games per week. Percentage of bermudagrass cover was visually rated weekly during the trafficking periods each year. Turfgrass quality was rated once before beginning traffic treatments each year. There were no consistent significant interactions (P > 0.05) among trinexapac-ethyl treatments and cultivars in either year of the study for either response variable. The main effect of cultivars was highly significant (P < 0.0001) for percentage of bermudagrass cover in both years of the study. Among cultivars, the ranges of percentage of bermudagrass cover at the end of the trafficking periods were 10.2% to 39.2% and 43.3% to 76.7% in 2004 and 2005, respectively. The main effects of trinexapac-ethyl on percentage of bermudagrass cover were significant (P < 0.0052) and more pronounced in 2004. Significant differences (P < 0.0200) were also recorded in 2005. Applications of trinexapac-ethyl resulted in increased tolerance to simulated traffic and improved turfgrass quality. Under the conditions of this study, data indicate that both cultivars and regular applications of trinexapac-ethyl have significant effects on overall turfgrass quality and the tolerance of these seeded bermudagrasses to simulated traffic.

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Callery pear (Pyrus calleryana) is an invasive tree across much of the eastern United States that can form dense thickets, and tree branches and stems are often covered in sharp thorns. Landowners and land managers attempting to manage callery pear infestations are faced with the challenge of killing and/or removing the trees while also avoiding thorn damage to equipment, which can lead to wasted time and increased costs. We evaluated fire as management tool to reduce the likelihood of equipment damage from callery pear thorns. Branches were collected in the field from callery pear trees that were killed by herbicide, and also from untreated trees, and half the branches from each group were then burned with a propane garden torch to simulate a low-intensity prescribed fire. After treatment, all branches were returned either to an old field or forest floor for 1 year, after which thorn puncture strength was evaluated and compared with freshly cut thorns. Herbicide treatment and location did not affect thorn strength, but burning reduced the likelihood that thorns would puncture a tire. Fire increased tip width, which reduced thorn sharpness. Burning also reduced wood strength, and fungi proliferated on burned thorns after 1 year in the field or forest. Both factors likely contributed to decreasing thorn strength and probability of puncture. Our results show that using prescribed fire as a management tool can weaken callery pear thorns and dull their tips, reducing the chance of equipment damage and costs associated with clearing land of this invasive species. Leaving cut callery pear trees on the ground for 1 year increased fungal colonization, which may also reduce thorn damage. Prescribed fire can be part of an effective integrated management plan for this, and possibly other, thorny invasive flora.

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Before analyzing the responses of Alabama garden center employees about the training they had received, we determined how satisfied 100 Alabama Master Gardeners were with the employee-s who helped them in the store from which they most often purchased plants for their homes, landscapes, or gardens. We mailed the primary survey to 472 employees of 130 retail garden center businesses in Alabama to determine the percentage of employees who received job training and the amount, frequency, and methods of training they received while working for their current employers (37% responded). Employees were categorized as managers (28%) or subordinate employees (72%) and full-time (72%) or part-time (28%). Forty-four percent of the employees had received some training at the time they were hired. Training continued for 68% of the respondents. Only 39% of the employees had a written description of their job responsibilities discussed with them. Most (85%) believed the training they received had prepared them to do their jobs well, but 82% said more training would increase their confidence in their work performance. Most employees were trained by one-on-one instruction (60%) and small-group sessions (5 or fewer persons) (65%). Few employees received training from videotapes (5%) or educational seminars (26%), and most that did were managers and full-time employees.

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The unprecedented, yet sustained, growth of undergraduate enrollment in the Department of Horticulture at Auburn University can be attributed to many factors, including an increased industry demand for horticulture graduates nationwide. Perhaps the basis of some of Auburn's growth, while appearing to be unique, may be of value in other programs. This paper chronicles the growth of the Auburn Department of Horticulture undergraduate program and highlights some of the traditional teaching methods employed within the department as well as some unique methods that contribute to the program. The paper offers ideas and practices that may be beneficial to other horticulture programs and may encourage teaching faculty at other institutions to publish similar departmental profiles that may prove beneficial to colleagues.

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The influence of three shade levels on propagation of golden barberry (Berberis koreana Palib. × B. thunbergii DC.) selection `Bailsel' was evaluated in studies initiated 29 Apr. and 18 Sept. 1998. After 57 days, root ratings were higher in plants under 70% and 80% shade treatments than 60% shade for both studies. In study one, viability was lower among plants under the 60% shade level than those under 70% or 80% shade levels. Viability among treatments was similar in study two. Based on visual observations, leaf retention appeared greater under the 70% and 80% shade treatments than the 60% shade treatment for both studies. Cuttings rooted under 70% and 80% shade levels generally had a uniform golden hue, whereas the foliage of those rooted under 60% shade often had a red hue and showed signs of desiccation for both studies. Root dry weights were greater for cuttings under the 60% shade levels than 70% or 80% shade.

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The Auburn University Shade Tree Evaluation is an ongoing trial of a moderately diverse range of species, and varieties of larger-growing trees. The study was initiated in 1980 with the planting of 250 selections in three replications of three trees each, located at the Alabama Agricultural Experiment Station, Piedmont Substation in east-central Alabama. Among the fruit of the investigation have been an evaluation of 10 red maple (Acer rubrum) selections with respect to growth and fall color characteristics; a comparison of growth rate and aesthetic characteristics of 14 oak (Quercus) selections; a comparison of the growth and fireblight (Erwinia amylovora) susceptibility of 10 callery pear (Pyrus calleryana) selections; and a 12-year evaluation of the overall best performing trees. The Shade Tree Evaluation has served as a precedent for six additional landscape tree evaluations in Alabama. It has provided a living laboratory for a wide range of educational audiences including landscape and nursery professionals, county extension agents, urban foresters, Master Gardeners, garden club members, and horticulture students. Knowledge gained from the Shade Tree Evaluation has been shared through presentations at meetings and conferences.

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Biological and chemical control strategies for the twospotted spider mite (TSM; Tetranychus urticae) were evaluated in a greenhouse experiment replicated over time in mixed production of ivy geranium (Pelgargonium peltatum ‘Amethyst 96’) and two impatiens cultivars (Impatiens wallerana ‘Impulse Orange’ and ‘Cajun Carmine’). Chemical control using the miticide bifenazate was compared with two release strategies for biological control using the predatory mite, Phytoseiulus persimilis. Specific treatments included 1) a single application of bifenazate at 0.3 g·L−1 formulation (22.6% a.i.); 2) a single release of predatory mites at a 1:4 predator to pest ratio based on sampled pest density; 3) a weekly release of predatory mites at numbers based on the area covered by the crop; and 4) an untreated control. TSM populations were monitored for 4 weeks. After another 4 weeks, when plants were ready for market, plant quality ratings were recorded. The number of TSM per leaf dropped for all treatments on all genotypes but increased in the untreated plants. On ivy geranium, the fact that there were significantly more TSM on untreated plants was not reflected in average plant quality, but it did reduce the proportion of containers rated as salable at full price compared with both chemical and biological control. On impatiens, both treatment and cultivar had significant effects on the mean plant quality rating and on the proportion of containers rated as salable at full price. The use of a sampling plan to determine the appropriate number of predators to release was as effective as the currently recommended management treatments for TSM in bedding plants.

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