Effect of Dazomet on Annual Bluegrass Emergence and Creeping Bentgrass Establishment in Turf Maintained as a Golf Course Fairway

Abstract

banned for agricultural and turfgrass uses in the USA (Ristaino and Thomas, 1997;Unruh, 1998). Dazomet (tetrahydro-3,5-dimethyl-2H-1,3,5-thiadiazine-2-thione)Dazomet is a granular soil fumigant that controls is a soil fumigant labeled for turfgrass renovation. Little is known about dazomet efficacy on annual bluegrass (Poa annua L.) seedling fungi, bacteria, nematodes, and weed seeds in soils (Haremergence, particularly when it is surface-applied. The objectives of ris, 1991;Fritsch and Huber, 1995). When incorporated this field study were to determine (i) the effects of rate and plastic into moist aerated soil, dazomet is degraded into several covering of surface-applied dazomet on annual bluegrass seedling volatile intermediate products including methylisothioemergence in turf; and (ii) effective creeping bentgrass seeding intercyanate (MITC). Methylisothiocyanate is toxic to many vals following surface applications of dazomet. All treatments were soilborne organisms, including weed seeds (Fritsch and applied to established turf during late summer in 2000 and 2001. , 1995;Mappes, 1995). Huber Covering dazomet treatments with plastic sheets resulted in fewerDazomet inhibits seed germination and emergence annual bluegrass seedlings than in noncovered treatments. All plasticof numerous weed species (Eitel, 1995;Mappes, 1995). covered dazomet treatments (388, 340, 291, and 194 kg ha Ϫ1 ) provided Efficacy varies with the rate of application and the greater than 98% reduction in annual bluegrass seedlings when compared with the plastic-covered controls during 2000 and 2001. When method of preventing escape of phytotoxic gases from not covered with plastic, the 388 kg ha Ϫ1 dazomet treatment provided soil. Eitel (1995) found improved control of seedling 97% fewer annual bluegrass seedlings in 2000 and 92% fewer seedlings emergence of Cyperus esculentus L., Galinsoga parin 2001 than the noncovered controls. Results of the seeding interval viflora Cav., Portulaca oleracea L., and Richardia braexperiment revealed that creeping bentgrass (Agrostis stolonifera L.) siliensis (Moq.) as rates of dazomet increased from 98 groundcover and yields were not inhibited when seeded 3 d after a to 392 kg ha Ϫ1 following incorporation into a sandy loam surface application of dazomet at 388 kg ha Ϫ1 .soil. When dazomet was incorporated into the same soil and covered with plastic sheets for 7 d, Eitel (1995) found improved control of the same four weed species

Establishment of Creeping Bentgrass in Annual Bluegrass Fairways Using Glyphosate and Interseeding

“…Results from this study showed that surface preparation method had little to no effect on the establishment of glyphosate‐resistant creeping bentgrass, indicating that the method employed is of minor importance. However, a successful establishment of bentgrass depends on the existing annual bluegrass being non‐competitive, and glyphosate has been the product of choice for annual bluegrass suppression and control (28). Glyphosate is a systemic, non‐selective, post‐emergent herbicide that is readily phloem translocated (30).…”

Annual Bluegrass Control in Seedling Creeping Bentgrass with Bispyribac-sodium

“…Creeping bentgrass ( Agrostis stolonifera L.) is widely used for golf course playing surfaces throughout the temperate and transition zone regions of the United States. Turf managers have attempted to convert ABG‐infested turfs to new cultivars of CBG, but the results are often unsatisfactory (13). The ABG soil seed bank is a significant source of new ABG seedlings that compete with CBG (7) often resulting in ABG populations similar to levels that existed prior to renovation.…”

Herbicide Applications and Incorporation Methods Affect Dazomet Efficacy on Bermudagrass

“…Following incorporation, dazomet reacts with water to produce methyl isothiocyanate, a gas that controls various fungi, insects, nematodes, and weeds (Brosnan and Breeden, 2009;Unruh et al, 2002). Under favorable conditions, methyl isothiocyanate formation is rapid (dazomet soil half-life <24 h), at which point it can volatilize and escape from the soil profile reducing control (Fritsch and Huber, 1995;Park and Landschoot, 2003). For this reason, management practices such as tarping and tillage are recommended to reduce atmospheric losses.…”

“…Applicators are recommended to cover treated soil with a plastic tarp, roll it, and/or irrigate to seal fumigant vapors into the soil, which can improve efficacy and reduce off-target movement potential (Amvac Chemical Corp., 2014). Park and Landschoot (2003) reported covering the soil with a plastic tarp immediately after dazomet application at 194, 291, 340, or 388 kgÁha -1 provided ‡98% annual bluegrass (Poa annua L.) seedling reduction; however, nontarped dazomet provided ‡92% seedling reduction only at 340 or 388 kgÁha -1 . The authors applied 0.5-and 0.25-inch water immediately after application in year 1 and 2, respectively, and 0.25 inch/d through 4 d (Park and Landschoot, 2003).…”

“…Park and Landschoot (2003) reported covering the soil with a plastic tarp immediately after dazomet application at 194, 291, 340, or 388 kgÁha -1 provided ‡98% annual bluegrass (Poa annua L.) seedling reduction; however, nontarped dazomet provided ‡92% seedling reduction only at 340 or 388 kgÁha -1 . The authors applied 0.5-and 0.25-inch water immediately after application in year 1 and 2, respectively, and 0.25 inch/d through 4 d (Park and Landschoot, 2003). This may have reduced annual bluegrass control in nontarped plots, as current label recommendations suggest applying 1 inch of water on the day of dazomet treatment, and up to 0.5 inch of water through the following 3 d (Amvac Chemical Corp., 2014).…”