Response of Yellow Nutsedge, Florida Pusley, and Peanuts to Thiocarbamate Herbicides as Affected by Method of Placement in Soil*

Abstract

Summary. Thiocarbamate herbicides were applied with incorporation devices and new subsurface application equipment on loamy sand at Tifton, Georgia, U.S.A. Subsurface‐applied ethyl N,N‐dipropylthiolcarbamate (EPTC), S‐propyl bulylethylthiocarbamate (pebulate), and S‐propyl dipropylthiocarbamate (vernolate) generally gave better control of Cyperus esculentus L. and Richardia scabra St Hil, but injured peanuts more than applications made on the soil surface and then incorporated into the soil. For soil incorporation, the power‐driven rotary hoe was generally better than a disc harrow. Depth of subsurface placement critically affected herbicidal activity, especially on Cyperus esculentus; placement 1·5 in. below the soil surface gave more effective control than placement at 5·5 in. Réactions de Cyperus esculentus, de Richardia scabra et de l'arachide mix herbicides à base de thiocarbamate, en relation avec la methode de placement dans le sol

Yellow Nutsedge (Cyperus esculentus) Interface in Peanut (Arachis hypogaea)

“…Yellownutsedge management in peanut is dependent on an integrated system of herbicides, mechanical, cultural, and biological control tactics (Hauser et al, 1966;Thurston, 1976;Linscott et al, 1978;Keeley and Thullen, 1983;Glaze, 1987;ThullenandKeeley, 1987;Gricharetal., 1992;Richburg et al, 1993Richburg et al, , 1994Grichar and Nester, 1997). Effective herbicides reduce tuber production and viability (Banks, 1983).…”

“…Effective herbicides reduce tuber production and viability (Banks, 1983). However, control with herbicides is often variable due to tuber depth, dormancy, and environmental factors that directly affect herbicide efficacy (Hauser et al, 1966;Thomas, 1969;Stoller et al, 1972;Stoller and Wax, 1973;Thullen and Keeley, 1975;Stoller et al, 1979).…”

INCORPORATED VERSUS SUBSURFACE VERNOLATE FOR WEED CONTROL TN PEANUTS*

“…Experimental devices Sweep applicator. The sweep applicator described by Hauser et al (1966) was used to spray vernolate in a broadcast swath 4 in. under the surface of preformed beds.…”

“…For 1967, we developed the Tifton injector-planter from the Tifton applicator-planter described previously (Hauser et al, 1966), modifying it to perniit simultaneous injection and planting with control over both seed and herbicide placement. We fabricated four gangs, each containing five injectors.…”

“…In previous studies, shallow subsurface layers of vernolate controlled yellow nutsedge better than sprays applied to the soil surface and then incorporated. However, shallow subsurface spraying injured peanuts more than incorporation (Hauser et al, 1966). The studies described herein evaluated newer subsurface application techniques, designed for maximum weed control with minimum crop injury, in comparison with conventional incorporation procedures.…”