Thursday, November 8, 2007 - 8:00 AM
337-1

Potential Dallisgrass Control Options.

Alan Estes, Horticulture, Clemson University, Clemson University, E 142 P&a Bldg, Clemson, SC 24634 and Lambert McCarty, E-142 P & As Bldg., Clemson University, Clemson University, Department of Horticulture, Clemson, SC 29634-0319.

Dallisgrass (Paspalum dilatatum) is a perennial grass weed common in most turf situations. Dallisgrass is a clumping perennial that produces unsightly seedheads in the summer and disrupts the uniformity of the turf. The purpose of this research was to investigate alternative dallisgrass control options with and without MSMA with various postemergence herbicides. In the summer of 2007 two studies were conduced at Clemson University investigating dallisgrass control with various Postemergence herbicides. Plot size for the each treatment measure 2.0 m by 3.0 m, replicated three times. Treatments were applied using a CO2 backpack sprayer calibrated at 20 GPA, at 31 p.s.i., with 8003 flat fan spray tips. Treatments for Study 1 included various rates, combinations, and timings of: MSMA (6.6L) at 2.0 lb ai/A; MSMA + Sencor (75DF) at 2.0 lb ai/A + 0.25; Sencor at 0.33 lb ai/A; MSMA + Revolver at 2.0 lb ai/A + 0.04 lb ai/A; MSMA + Certainty (75WG) at 2.0 lb ai/A + 0.06 lb ai/A; Plateau (2L) at 0.02 lb ai/A; MSMA + Plateau at 2.0 lb ai/A + 0.02 lb ai/A; Image (70DG) at 0.5 lb ai/A; Image + Sencor at 0.5 lb ai/A + 0.25 lb ai/A. Treatments for Study 2 included various rates, combinations, and timings of: Roundup Pro (4L) + Revolver at 0.125 lb ai/A + 0.04 lb ai/A; Roundup Pro + Revolver at 0.25 lb ai/A + 0.04 lb ai/A; MSMA + Revolver at 2.0 lb ai/A + 0.04 lb ai/A; MSMA at 2.0 lb ai/A; Revolver at 0.04 lb ai/A; Roundup Pro at 0.125 lb ai/A; Roundup Pro at 0.25 lb ai/A; Sencor + Plateau at 0.5 lb ai/A + 0.02 lb ai/A; Sencor + Revolver at 0.5 lb ai/A + 0.04 lb ai/A; Sencor + Certainty at 0.5 lb ai/A + 0.06 lb ai/A; Sencor at 0.5 lb ai/A. Visual control ratings were taken throughout the study. Ratings for dallisgrass control were based on a scale of 0 – 100% with 0% representing no control and 100% representing complete control. ‘Tifway’ Bermudagrass turf injury was evaluated on a 0 – 100% scale with 0 % representing no turf injury and 100% representing dead turf.