Velocity, (bis pyrobac-sodium) was applied at different ai/a rates in multiple application series to evaluate treatments for post emergence seed head and vegetative control of Poa annua var. annua. Velocity herbicide, when applied to perennial ryegrass overseed turf with heavy PA infestations, caused periodic discoloration of the ryegrass and yellowing/bronzing of the PA. The leaf yellowing of PA caused by Velocity is in contrast to color enhancement of PA from Proxy/Primo tank mixes. Seed head suppression of PA from Velocity was slightly greater in early April, than in early March. As cumulative treatment amounts of active ingredient of Velocity increased, the seed head suppression increased for treatments beyond the 30 + 30 gm ai/a rate. Above this rate, seed head suppression was increased, but not consistently with the applied active ingredient rate. Seed head suppression of PA on March 5 from Velocity ranged from 35% to 75% among Velocity treatments applied at 30, 45 and 60 grams ai/a. Embark alone had fair seed head suppression from early to mid-March, but decreased dramatically afterwards. There was no benefit of the 30 + 60 gm ai/a treatment, over the 60 + 60 gm ai/a treatment for seed head suppression of PA. Biological response in terms of absolute rate of ai/a applied and response to cumulative amounts of total Velocity were not consistent for PA seed head suppression or vegetative control. No product affectively reduced vegetative control of PA in a highly infested stand of PA which was 40-50% PA. If Velocity is to be competitive against other PA seed head reducing products, rate structures and timings may have to be amended for more multiple applications.

Several items need consideration when products are evaluated for use as transition agents. These are (1) efficacy of ryegrass removal [rate of ryegrass decline and appearance of turf during transition], (2) tolerance and performance of incoming bermudagrass and (3) application safety for next season’s repeat overseed operations. This test was designed to evaluate application safety for the next overseeding which occurs in the early fall. Therefore, AEF was applied in the summer to bermudagrass turf prior to overseed operations. Most responses of the perennial ryegrass (overseed) turf to previous treatments of AEF 130360 occurred immediately after overseeding, from mid-October to early November. AEF 130360 applied 2 weeks before overseeding caused a significant decrease in seedling vigor, percent plot ryegrass cover, and percent bermudagrass plot straw present. Both AEF treatments applied closest to overseeding (2 weeks prior) had the least amount of initial ryegrass, the greatest amount of green bermudagrass, and later in the season, the most amount of straw (dormant) bermudagrass. Differences in turfgrass quality were not significant due to treatments at any time throughout the test, and most treatments ranked higher than the control in overall quality. Under the conditions of this test, application of AEF 130360 at either 0.64 or 1.28 ounces/product/M made one month before actual oversseding did not cause detrimental effects to ryegrass emergence, ryegrass cover, turfgrass color or overall quality.

Proxy (ethephon) was applied to 100% pure stands of Poa annua as either a single or repeat application 24 days apart at both a five and ten-ounce product rate per 1000 square feet. Percent plot seed heads were decreased significantly on three of five evaluation dates before either the loss of treatment effect and/or environmental conditions triggered profuse flowering (by 20 April, 2000). The five-ounce rate produced moderate seed head suppression at 16 and 25 days after the first treatments by which afterwards, control was minimal. By April, the five-ounce repeat applications were no better in suppression of seed heads than either of the single applications, regardless of application timing (March 3 or 29). The ten-ounce rates generally produced 40% - 80% greater seed heads suppression than the five-ounce rate treatments. Maximum seed head control was achieved by the repeat applications (March 3 and 29) of the ten-ounce rate, which consistently produced between 8% and 19%, seed head cover up until the first ten days of April 2000. Proxy, when applied at the five-ounce/M rate had the greatest effect in seed head suppression early in the test (10 March). Perhaps earlier season applications at the five-ounce rate may be necessary to manifest greater suppression initially, and perhaps in a cumulative fashion for season long control.

Several new sulfonylurea products have (or are being) brought to market for use in turf. One use of these products is for removing ryegrass from overseeded bermudagrass, since perennial ryegrass has become too persistent due to improvements in heat, drought, and close mowing tolerance. The soil half life of sulfonylurea is greatly increased in high pH soils, which are typical in the southwest. Superintendents may need to re-establish seeded bermudagrass after use of a S.U. transition agent if the underlying bermudagrass is sparse. With this in mind, a replicated field trial was conducted in summer 2004 to evaluate three rates of foramsulfuron (0.4, 0.8, 1.2 ounce /product/1000 ft2) herbicide at 0, 7, 14, and 28 days after seeding. Foramsulfuron is sold as Revolver. Revolver applied at time of seeding (0DAS) and 1 week after seeding (7 DAS) caused the greatest amounts of bermudagrass suppression in terms of bermudagrass plot cover and visible seedling vigor. When applied (7 DAS), bermuda cover (averaged over all three applied rates of Revolver) at 21, 28, and 36 DAS was 8%, 22% and 32% bermuda cover, respectfully, versus NTC mean values of 22, 49 and 54% cover, respectively. The second greatest degree of Bermuda suppression occurred from Revolver applied at the day of seeding (0 DAS). The effects lasted up until and included the end of the test on 29 Sept (36 DAS). When averaged over all 3 applied rates of Revolver, percent plot bermudagrass cover at 21, 28, and 36 DAS was 10%, 30% and 40% respectively for the 0 DAS treatments. The NTC cover for these same dates was 22%, 50% and 53% respectively. Vigor visual scores were minimal as well for all rates applied at (0 DAS) and at (7 DAS). Plots remained stunted up to 36 DAS for Revolver turfs applied at (7 DAS) and (0 DAS). Application at the time of seeding (0 DAS) resulted in more bermudagrass plot cover than if applied at (7 DAS). Rate reduction responses were realized only for Revolver application timings made at 0 DAS and 7 DAS (Table 1, 5, Figs. 1-4). No rate responses resulted for Revolver when applied at 14 DAS, 28 DAS. In conclusion, Revolver was safest when applied 14 DAS or later, with little rate effects.

Khakiweed (Alternanthera pungens) was treated late in the season with select herbicides for initial screening of herbicides for post emergence control. Treatments were applied on October 7, 2004 and evaluated five weeks after treatment on Nov 16, 2004. The F ratio for the treatment main affect was highly significant for percent weed control. All rate affect contrasts were not significant for those treatments applied at two or more active ingredient levels. The "S.U. herbicides" vs. "all others" contrast was significant at P=0.05, as the S.U.. chemicals as a whole provided better coverage than the 2-4, D type and Penoxsulam. Percent weed control ranged from 7% to 99% late season control of Khakiweed. There were noticeable differences between S.U. products, as Revolver provided minimal weed control (7%) while Manor and Monument provided very good to excellent control (94% to 99%). Both Manor rates resulted in 99% control, while the three rates of Monument produced 94%-98% mean percent weed control values. Penoxsulam was intermediate, providing 56% and 70% control for the SC and G formulations, respectively. Banvel, 2-4, D and Buctril produced 22%-24% Khakiweed control. Tranxit had minimal affect (12%), as did Revolver at 6%.

Kentucky bluegrass (Poa pratensis L.), cv. Nu Star was studied in a greenhouse to evaluate its growth responses in terms of shoot length and dry weight under NaCl (sodium chloride) salinity and different levels of Trinexapac-ethyl( primo Max). Plants were grown hydroponically under control and one level of salinity [EC (electrical conductivity) of 5 dS/m] and three levels of primo Max (0.3, 0.6, and 0.9 oz/1000 ft²), using Hoagland solution No. 1. Plant shoots (clippings) were harvested weekly, oven dried at 60 oC, and dry weights recorded. At each harvest, shoot length was measured and recorded, percent visual canopy green cover was also estimated. The results show that shoot length and shoot dry weight (DW) of Kentucky bluegrass significantly decreased with both salinity and primo treatments, although the differences in shoot length and shoot DW were not significant between primo treatments at 0.6 and 0.9 oz/1000 ft² application rates. The green coverage of the turf canopy decreased under salinity stress, and the reduction of green canopy coverage by salinity was more pronounced when turf was treated by primo, suggesting that primo significantly reduced the salt tolerance of Kentucky bluegrass. The above results were observed for both cumulative as well as the weekly growth responses.

No description available.

The ET rate of bermudagrass is relatively well known. The ET rate of Seashore paspalum in an arid environment is not, nor is there any information on the ET of Distichlis as a mowed turf. A greenhouse test using gravimetric lysimeters was conducted in the late summer of 2004 to measure and compare the ET of two Distichlis clones and Sea Isle 1 seashore paspalum to that of Tifway 419 bermudagrass. This test showed that under glass house conditions when soil moisture was not limiting: (1)Seashore paspalum had a higher ET rate than A119 saltgrass in terms of mm/day, and total consumptive water use for the 19 day test period, (2) A48 saltgrass and Tifway bermudagrass had similar daily ET rates and similar total water use, (3) total water use between two select saltgrass clones was not significantly different . Saltgrass A48 and A119 had a total consumptive water use of 84.2 and 76.5 mm, respectively over the 19 day test period. Tifway Bermuda totaled 82.2 mm, and Sea Isle 1 used 92.1 mm over 19 days.

Sixty-four overseed turf entries were evaluated from October 2002, to June 2003 for turf when overseeded on Tifway bermudagrass fairway turf. Overseed entries included 43 single variety (or experimental synthetics) of perennial ryegrass, 2 annual ryegrasses, 6 entries of intermediate or 'hybrid' ryegrass, 5 entries of Poa trivialis (PT), one blend of perennial ryegrass, 4 mixtures (two or more species together) and 3 fescues. The main effect of "overseed grass entry" was highly significant on all dates for all visual turf responses, which included establishment, color quality, density, texture, and spring transition. The greatest amount of variation occurred within the perennial ryegrass group as a whole, showing the diversity within this species for overseeding performance. Annual ryegrass provided quick germination and ground coverage in the fall and a quick spring transition, but was of poor turf quality. Intermediate ryegrasses had performance values between that of perennial and annual ryegrass, some of which provided moderately good turf performance and good transition. Poa trivialis was slow to establish, but provided good quality and excellent plot texture, however they had poor transitional qualities. Final quality mean scores ranged from 3.0 (P-02-0047 PT) to 7.7. There were three entries, which averaged 7.7 at the close of the test, which included Mach 1 PR, SR 4500 PR, and Pace PR. The entries IG-2, Greenville PR, Express PR, Bar LO 2001, Hawkeye, Partee finished at 7.3 for quality. Among the intermediate ryegrass entries, Froghair finished with a mean quality score of 7.0, followed by Pick 00- A-LH (5.3). All three fescues produced mean quality scores of 6.0 or better on 8 June (Hardtop fescue leading at 6.7 for quality). The Labarinth tall fescue did have 62% Bermuda at the end of the test, compared to 65% for all entries at that time. Entries which had a mean quality score of 7.0 or more in June, along with a bermuda transition of close to 75% or more at the termination of the test included the following entries; Citation Fore, Mach 1, BarGold, Bar LP 2001, Pace, Greenville OSP, and Express.

The new Seashore paspalum 'Sea Isle 2000' is being used as a greens surface in many tropical - semi tropical climates were saline water is available for irrigation. While it’s color retention in the fall in Tucson Arizona is good, it still enters full winter dormancy, and requires overseeding with a cool season grass for late fall, winter, and spring play. A two year test was conducted to evaluate the tolerance of Sea Isle 2000 to overseeding, and to evaluate overall turf performance of perennial ryegrass (PR), Poa trivialis (PT) and a mixture of the two when used for overseeding over Sea Isle 2000. PT alone was slow to establish as an overseed in year one, but not in year two. Turfgrass color, quality density and texture were acceptable throughout the test, noting that the 100% perennial ryegrass plot demonstrated a short-term loss of performance during the cold January of 2004. After the initial grow in period, absolute BRD was greatest when growing conditions were less than optimum in mid-winter, and again at the seasons end at the beginning of spring transition (May). This was true in both years. BRD was generally not different between the three overseeding regimes, either when turfs were double mowed prior to BRD measurements, or when a single rolling event was added on the day that BRD was assessed. The 100% PR overseed treatment showed the largest numerical increases in BRD from rolling. This was 6.5 inches in year one and 9.2 inches in year two. Yearly BRD averages of all overseeded surfaces for turfs that were double mowed in year one ranged from 91.5 to 92.4 inches, and in year two from 92.2 to 93.3 inches. Average yearly BRD values among all overseed turfs when rolling was included (including double mowing) in year one ranged from 95.8 to 98.2 inches and from 99.2 to 100.5 inches in year two. Maximum BRD values obtained were 107.8 and 114.3 inches in year one, and 100.0 and 111.1 inches in year two for the mowed only turfs, and mowed and rolled turfs, respectively.