Development and Rooting of Kentucky Bluegrass Sod as Affected by Herbicides1
- J. A. Jagschitz
Herbicides used for weed control on Kentucky bluegrass (Poa pratensis L.) grown for commercial sod may delay its development or interfere with rooting after transplanting. In these studies, herbicides were applied on immature and mature sod for control of annual grasses and on mature sod for control of broadleafed weeds. Sod development was evaluated by sod strength measurements and estimates of grass stand. The herbicide effect on rooting of transplanted sod was determined by measuring the weight of roots grown from sod plugs on sand and by measuring the force required to lift sod plugs from soil.
Mature sod was safely treated with mixtures of 2, 4-D [(2, 4-dichlorophenoxy) acetic acid] with either dicamba (3,6-dichloro-o-anisic acid), mecoprop [2-[(4-chloro-o-tolyl)-oxy]propionic acid], or silvex [2-(2,4,5-trichlorophenoxy)propionic acid] at least 4 weeks before or after transplanting in the spring or 4 weeks before transplanting in the fall. Some root inhibition took place when sod was treated earlier or if treated 4 weeks after transplanting in the fall.
Immature sod treated with benefin (N-butyl-N-ethyl-α,α,α-trifluoro-2,6-dinitro-p-toluidine), bensulide [O, O-diisopropyl phosphorodithioate S-ester with N-(2-mercaptoethyl) benzenesulfonamide], butralin [4-(1,1-dimethylethyl)-N-(1-methylpropyl)2, 6-dinitrobenzenamine], DCPA (dimethyl tetrachloroterephthalate), oxadiazon [2-tert- butyl-4-(2,4-dichloro-5-isopropoxyphenyl)-Δ2-1,3,4-oxadiazolin-5-one], and prosulfalin [N-[[4-(dipropylamino)-3,5-dinitrophenyl]sulfonyl]-S, S-dimethylsulfilimine] was less dense and/or exhibited reduced sod strength up to 11 weeks following treatment. Sod treated with bensulide and prosulfalin was weaker up to 25 weeks after treatment. Bensulide and prosulfalin inhibited the rooting of sod transplanted 23 weeks after treatment. Some reduction in rooting was noted with sod treated 15 weeks earlier with benefin and DCPA. Siduron [1-(2-methylcyclohexyl)-3-phenylurea] was safe to use on immature sod. Mature sod treated with benefin, bensulide, and prosulfalin showed some root inhibition when transplanted within 10 weeks. It appeared safe to use butralin, DCPA, oxadiazon, and siduron on mature sod to be transplanted after 5 weeks.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © 1980. . Copyright © 1980 by the American Society of Agronomy, Crop Science Society of America, Soil Science Society of America, and International Turfgrass Society, 5585 Guilford Rd., Madison, WI 53711 USA