Subsurface Application and Shallow Incorporation of Herbicides on Cotton

Abstract

In a 3-year study on four soil types, subsurface application just ahead of a planter with a device that removed the top from the bed, applied a band of spray, and covered the band with soil reduced weed control in cotton (Gossypium hirsutum L.) obtained with 3-(3,4-dichlorophenyl)-1,1-dimethylurea (diuron), 2,4-bis(isopropylamino)-6-methylmercapto-s-triazine (prometryne), 3-(hexahydro-4,7-methanoindan-5-yl)-1,1-dimethylurea (norea), dimethyl-2,3,5,6-tetrachloroterephthalate (DCPA), and 1,1-dimethyl-3(α,α,α,-trifluoro-m-tolyl)urea (fluometuron) compared to applications on the soil surface. This machine improved weed control with α,α,α,-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine (trifluralin). Shallow incorporation, with two helical blades, after planting increased weed control with trifluralin, diuron, and DCPA by 10% or more over the surface applications. This incorporator increased weed control obtained with prometryne and norea 5%. Very shallow incorporation, with metal tines, after planting improved weed control obtained with trifluralin and DCPA 18 and 11%, respectively. Weed control with norea was increased 7%, but metal tines did not appreciably affect weed control obtained with prometryne, diuron, or fluometuron. Compared to surface applications, incorporation increased cotton injury with diuron, norea, prometryne, and fluometuron on sandy loam soil.