worker exposure. Tree fluazifop + glyphosate applications resulted in < 5 percent cover at the final evaluation date and should be considered for renovations where effective dazomet treatment regimens are not feasible and there is ample time for sod fields to remain out of use.
Overall, results from this research suggest that there may often be a difficult, yet fairly straightforward decision to make when eradicating perennial grasses or troublesome weeds for re-planting. Eradication is possible with 3 relatively cheap fluazifop + glyphosate applications but can take a significant amount of time. Or, eradication is also possible with one fluazifop + glyphosate application prior to dazomet application at a higher price tag, but in a much shorter treatment duration of 8 days. Even with recommended plant-back dates ranging from 8 to 15 days (dependent on soil temperature) after dazomet application, substantial time savings are possible. Tis is an important consideration for sod farms, because the establishment period for the newly planted grass can be substantially decreased. Ultimately, it comes down to this one simple closing thought, “Perennial grasses can be eradicated cheaply, or quickly, during grass field renovations, but not both.”
Te core take-away messages from this research include: • Dazomet may serve as a suitable methyl bromide replacement for common bermudagrass control when re-planting seed or sod fields.
• Compared to treatment regimens solely using nonselective herbicides such as glyphosate and
• Dazomet soil-incorporation by irrigation provided acceptable common bermudagrass control only in North Carolina, which may be due to a shorter growing season compared to Texas.
fluazifop, dazomet can substantially reduce the time required for common bermudagrass eradication.
• Tarping dazomet following tillage-incorporation did not improve common bermudagrass control and is not recommended for turfgrass renovations, especially in large-scale operations such as seed or sod production fields.
• Over both locations, fluazifop + glyphosate pretreatment followed by tillage-incorporated dazomet at 525 pounds/acre, resulted in > 90 percent bermudagrass eradication at the final evaluation date, almost 1 year after initial treatment.
• For cool-season weeds, including Annual bluegrass, Dr. Trey Rogers and his associates at Michigan State University have been researching application methods to optimize Basamid applications for annual bluegrass control. Te variables being evaluated include site preparation, method of Basamid incorporation (water vs. mechanical) and fraze mowing. Teir 2019 field trials will be available for viewing at the Michigan State University Turfgrass Field Day next August.
Fred Yelverton, PhD, is a Professor and Extension Specialist in Turf & Forage Weed Science in the NCSU Department of Soil and Crop Sciences. Travis Gannon, PhD, is Associate Professor, Pesticide Fate and Behavior, in the NCSU Department of Soil and Crop Sciences. Casey Reynolds, PhD, is executive director of Turfgrass Producers International.
Research plot area after all herbicide applications have been applied at the Texas A&M University research location in College Station, TX. Te green plot is an un-treated control.
54 TPI Turf News March/April 2019
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68
