Herbicide Effects on Bermudagrass Lawn Recovery and Crabgrass Control during Spring Root Decline in the North-South Transition Zone

Abstract

<jats:p>A bermudagrass <jats:italic>[Cynodon dactylon</jats:italic> (L) Pers. × <jats:italic>C. transvaalensis</jats:italic> Burtt-Davy `Tifgreen'] lawn in the transition zone (about lat. 35°N) was treated in late March for 3 years with a high and a low level each of benefin, bensulide, DCPA, oxadiazon, and siduron. Objectives were to determine if relationships exist between field environment and dates of preemergence herbicide applications for large crabgrass <jats:italic>(Digitaria sanguinalis</jats:italic> L. Scop.) control, the spring root decline (SRD) phenomenon, and herbicide phytotoxicity to the bermudagrass. Herbicide treatments in late March generally controlled large crabgrass, reduced total weed competition, and appeared to aid bermudagrass spring growth following winter dormancy. Herbicide injury to `Tifgreen' bermudagrass roots during SRD does occur under practical field conditions and was more severe when bermudagrass spring green-up occurred closer to the herbicide treatment date, as in 1982. Bermudagrass stand density was significantly reduced with the high level of siduron in 1980 and 1981, and with both levels of oxadiazon and siduron in 1982. Bensulide and oxadiazon, at both levels, gave 92% to 100% crabgrass control during all three treatment years. The high levels of benefin and DCPA in 1980, both levels of benefin and the high level of DCPA in 1981, and both levels of DCPA and the high level of benefin in 1982 gave crabgrass control in excess of 95%. Chemical names used: N-butyl-N-ethyl-2,6-dinitro-4-(trifluoromethyl)-benzenamine (benefin), O,O-bis(1-methylethyl)-S-[2-[(phenylsulfony l)-amino]ethyl] phosphorodithioate (bensulide), dimethyl 2,3,5,6-tetra-chloro-1,4-benzenedicarboxylate (DCPA), 3-[2,4-dichloro-5-(1-methylethoxy)phenyl]-5-(l,l-dimethylethyl)-l,3,4-oxadiazol-2 -(3H)-one (oxadiazon), N-(2-methylcyclohexyl)-N'-phenylurea (siduron).</jats:p>

Dwarf Bermudagrass Tolerance to Preemergence Herbicides

“…Results with oxadiazon applied to 'Tif Eagle' bermudagrass are consistent with previous research by Callahan and High (1990) who found minimal to no foliar injury during spring transition on 'Tifgreen' bermudagrass. Johnson (1976bJohnson ( , 1979 noted spring applications of oxadiazon at 3.4 and 4.5 kgÁha -1 did not affect quality or density of 'Tifway', 'Tifgreen', 'Tifdwarf', 'Ormond', or 'Floraturf' bermudagrass when maintained at 20 to 40-mm mowing heights, but injury was reported from fall applications.…”

“…Oxadiazon has residual activity of 8 to 15 weeks and inhibits the enzyme protoporphyrinogen oxidase causing loss of chlorophyll and eventually membrane leakage (Rao, 2000). On 'Tifgreen' bermudagrass, oxadiazon gave 100% control of Digitaria sanguinalis (L.) in 3 consecutive years (Callahan and High, 1990). Single and sequential applications of oxadiazon effectively control Kyllinga squamulata, annual bluegrass, and goosegrass (Eleusine indica L.) in higher-mowed bermudagrass turf (Johnson, 1976a;Bunnell et al, 2001;Toler et al, 2003).…”

Investigating low-dose herbicide programs for goosegrass (Eleusine indica) and smooth crabgrass (Digitaria ischaemum) control on creeping bentgrass greens

“…In that study, metamifop controlled smooth crabgrass comparably to the current study and fenoxaprop applied thrice at 3-wk reapplication intervals controlled smooth crabgrass by 74%, which is significantly lower than our results from eight weekly treatments. Of 22 peer-reviewed papers we reviewed that reported siduron use in turfgrass, only three assessed siduron use in mature turfgrass systems for smooth crabgrass control (Callahan and High 1990;Callahan et al 1983;Murray et al 1983) and none evaluated goosegrass or smooth crabgrass control in creeping bentgrass. These papers generally indicate that siduron applied once or twice per year does not offer seasonlong smooth crabgrass control.…”

Preemergence Herbicides Influence Sprig Establishment of ‘TifEagle’ Bermudagrass

“…Oxadiazon is a protoporphyrinogen oxidase inhibitor that effectively controls annual weeds, such as Asian spikesedge (Kyllinga squamulata Thonn. ex Vahl), annual bluegrass (Poa annua L.), large crabgrass (Digitaria sanguinalis L.), and goosegrass (Eleusine indica L.) in established bermudagrass fairways (Brecke et al 2010;Bunnell et al 2001;Callahan and High 1990). Oxadiazon can be applied during bermudagrass establishment from sprigs and has been shown not to reduce rooting of Tifgreen, Tifdwarf, or Tifway bermudagrass (Bingham and Hall 1985;Brecke et al 2010;Fagerness et al 2002;Johnson 1980Johnson , 1985McCullough et al 2007).…”