Dimension herbicide (dithiopyr) was applied to common bermudagrass turf at 90, 60, and 45 days before fall overseeding to measure the efficacy for turf safety and for control of fall germinating POA Annua (PA). Applications were made at 0.25, 0.375, and 0.50 lbs. AI/A on each date. One half of each plot was overseeded, while the other half was not. Percent plot (PA) infestation and percent weed control was more greatly affected by the process of overseeding, than that of the herbicide applications alone. When not overseeded, the bermudagrass turf had a maximum of 45% PA control in November, which decreased dramatically to little or no control from January to March 2000. With the inclusion of ryegrass overseed, the high rate (0.50 lbs. AI/A) applied closest to the overseeding (45 DBOS) provided between 79-82% PA control over the length of the test. Actual infestation levels among non-chemical receiving control plots showed a 3X increased level in PA suppression due to overseeding, when compared to the non-overseeded, non-chemical controls. Dimension herbicide alone had little effect for PA control. When combined with overseeding, the 0.50 lb. AI/A rate, applied at 60 or 45 DBOS provided the greatest levels of PA control. The performance of Dimension on non-overseeded bermudagrass does not support the anticipated use of this chemical for PA control.

Increased demand for golf course greens with fast ball speeds and aesthetically pleasing turf present the greatest public pressures that golf course superintendents face today. In the desert southwest, the annual summer monsoon rainfall pattern brings increased atmospheric humidity which results in an increase in the tendency of SR1020 creeping bentgrass to build-up thatch. The effects of four different cultural practices on color, quality, thatch, and ball roll were evaluated on a SR1020 creeping bentgrass green built to USGA specifications grown in an arid environment during a period of increased atmospheric humidity and rainfall. Plots that were verticut/topdress once every two weeks showed unacceptable color, quality, and ball roll. Rolling twice a week had no significant impact on color, quality, and thatch, however, rolling did have a slightly positive impact on ball roll. Grooming three times per week had no significant impact on thatch reduction, and resulted in decreased color, quality and ball speed. Topdressing one time per week did decrease the natural tendency of thatch build-up in SR1020 during periods of increased atmospheric humidity. Topdressing one time per week slightly increased color, quality, and ball roll.

A test was devised to investigate a forced spring transition from perennial ryegrass, back to Tifway (419) bermudagrass with scalping as the main treatment. Scalping of the turf was combined with various nitrogen and aerification treatments performed initially on May 22, 1997. Turfgrass aeration, either with or without extra nitrogen applications, when combined with an initial scalping operation, did not enhance bermudagrass transition by twenty-eight days after treatment (DAT), at the end of June 1997. Turfgrass color, quality and density were adversely affected from initial aerification treatments, especially when combined with initial scalping, The turf recovered best from multiple applications of nitrogen (applied at scalping and again at 7DAT). Turfgrass density (visual estimates) showed that in conjunction with scalping, two applications of nitrogen, totaling 1.5 lbs./month, without aerification, provided a dense turf at 16DAT, which was second only to the untreated control plot. At 27 DAT, scalping + N + N + aerification treated plots had the highest estimate of visual density, eventually showing a benefit from aerification. Scalped and aerified turf alone (no nitrogen) had unacceptable turf density at 16DAT and 27DAT. Generally, two 0.75 lb./N/m applications with aerification proved beneficial over the single application of nitrogen plus aerification, when both turfs were initially scalped. Although non-significant statistically, the additional treatment of nitrogen provided 10% more bermudagrass cover than the single application of nitrogen, for turfs both overseeded and scalped. Scalping alone, plus a single application of N, produced 33% less bermudagrass by June 30, then that of the untreated control.

In six field experiments that were conducted during the spring of 2004 with seven sulfonylurea herbicides for removing perennial ryegrass from bermudagrass turf, the most rapid response and effective ryegrass removal occurred with the latest applications made in June compared to applications made in April or May. Flazasulfuron, foramsulfuron, rimsulfuron, trifloxysulfuron, and chlorsulfuron were effective in removing most of the ryegrass. Sulfosulfuron and metsulfuron were least effective for removing ryegrass, especially during the cooler April and May timings.

Aquatrols surfactant ACA 1848 was applied to Tifway 419 hybrid bermudagrass at rates of 12 or 48 ounces/acre and evaluated for turfgrass growth, performance, and nutrient uptake. Soil samples collected during the growing season were analyzed for inorganic nitrogen (ammonium and nitrate). Only on the last sampling date only (September 29), the soil nitrate-nitrogen level was slightly higher in the untreated control than in other plots. Otherwise, soil nitrogen levels did not differ among treatments. Growth measurements and visual ratings did not differ among treatments at any time during the growing season, indicating that surfactant treatments did not affect either of these parameters. Leaf clippings collected throughout the growing season were analyzed for total nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, sodium, boron, copper, iron, manganese, and zinc. With only one exception, differences in nutrient content among treatments were statistically non-significant at the 5% significance level. That exception occurred on August 18 when the turfgrass treated with surfactant at the 12 oz/a/wk level had less zinc than turfgrass in the 0 or 48 oz/a/wk treatments. There was a noticeable, but non-significant trend, observed as follows; the highest level of surfactant treatment (48 oz/a/wk) resulted in the highest tissue levels of phosphorus, potassium, sulfur, sodium, boron, and copper in samples collected on July 21 (day 203), August 4 (day 217), and September 1 (day 245). Calcium, magnesium, and iron levels were highest in this treatment on August 4, but these differences were extremely small and always statistically nonsignificant and this trend was not observed on other sampling dates. There were no consistent rate trend responses (i.e. where the higher level of surfactant treatment produced a greater response than the lower rate) throughout the test. On all sampling dates, the untreated control contained more manganese than either of the surfactant treatments; the differences were not statistically significant and were not rate related. In this field study, there were no turfgrass responses, either positive or negative, that we could attribute to Aquatrols ACC 1848 applied at 12 and 48 oz/a weekly. The magnitudes of response differences observed in this study were not large enough to identify statistically significant differences.

Bermudagrass (Cynodon dactylon L.), cv. Arizona Common was studied in a greenhouse to evaluate its growth responses in terms of shoot and root lengths and shoot and root dry weights under different levels of nutrients. Plants were grown hydroponically under five levels of nutrients in the growth medium [Full Nutrients (FN), Half Nutrients (½N), Quarter Nutrients (1/4N), One Eighth Nutrients (1/8N), and One Sixteenth Nutrient (1/16N)], using Hoagland solution No. 1. Plant shoots (clippings) were harvested weekly, oven dried at 60 °C, and dry weights recorded. At each harvest, both shoot and root lengths were measured and recorded. At the last harvest, plant roots were also harvested, oven dried, and dry weights were determined and recorded. The results show that shoot length, shoot and root dry weights, shoot total-N contents and concentrations, and the % of canopy green cover significantly decreased at lower (1/8 & 1/16) nutrient levels. This reduction was more pronounced as growth period progressed. Root length was stimulated at lower (1/4, 1/8, and 1/16) nutrient levels of the culture solutions. The differences in shoot lengths and shoot and root dry weights were not significant among the Full, 1/2, and 1/4 nutrient levels of the culture solutions. The differences in shoot total-N content and concentrations were not significant among the Full, 1/2, and 1/4 nutrient levels. There was no difference in either shoot total-N contents or concentrations among the respective nutrient treatments at different harvests. The above results were observed for both cumulative as well as the weekly growth responses.

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No description available.

Two rates of Foramsulfuron (TADS) were applied at both low (0.50 lbs/M) and high (1.0 lbs/M) rates of water soluble nitrogen in May 2003 to enhance the transition from ryegrass to bermudagrass. Overall, the 0.2-ounce product/M rate of TADS herbicide, regardless of applied -N- rate produced excellent turfgrass color, density and overall turf quality. The same 0.2-ounce rate produced a good spring transition. Overall, the 0.4-ounce rate of TADS produced slightly more bermuda than the 0.2-ounce rate at the "end" of the transition (June 6). The higher fertility rates yielded better quality, color and turf density during transition then the low -N- rate when TADS was applied at the 0.4-ounce/product/M rate. Note that Tifway bermudagrass has in general, a more decumbent growing bermuda than common bermudagrass, which is less competitive during spring transition than Tifway 419. In summary, all rates of TADS enhanced spring transition. When the high rate of TADS is used on Tifway 419 (0.4 ounce/product/M), then better turf performance was achieved with the higher -N- rate applied in early May.

Zoysiagrass (Zoysia spp.), cv. El Toro was used in this experiment to evaluate its shoot growth in terms of length and dry weight under control and different levels of Bio-Turf-Pro applications in a pot study. Four treatments [Control (no Bio-Turf-Pro), 8 Fl Oz/Gal (½ the recommended rate) per 1000 ft², 16 Fl Oz/Gal (recommended rate) per 1000 ft², and 32 Fl Oz/Gal (twice the recommended rate) per 1000 ft² of Bio-Turf-Pro], and six replications of each treatment were used in a RCB design in this investigation. Plants were allowed to grow under the above treatment conditions for eight weeks. Plant shoots (clippings) were harvested bi-weekly for the evaluation of the dry-matter production. At each harvest, shoot lengths were measured and recorded and the visual growth was also evaluated before the harvest was made. The harvested plant materials were oven dried at 60o C and dry weights were measured and recorded. The shoot growth (length) was stimulated under any levels of Bio-Turf- Pro application rates compared with the control. Among the treatment rates, the 16 Fl Oz/Gal (the recommended rate) per 1000 ft²] numerically stimulated the shoot length the most. However in most cases, there was not statistically significant differences detected among the 8 (½ the recommended rate) per 1000 ft², 16 Fl Oz/Gal (the recommended rate) per 1000 ft²] and the 32 Fl Oz/Gal (twice the recommended rate) per 1000 ft²] application rates of the compound on the shoot length of the grass. The shoot (clippings) dry weights of the plants followed essentially the same pattern as the shoot lengths. The visual evaluation of the grass supported the measured parameters.