No‐Tillage Maize Production in Chemically Suppressed Grass Sod1

Abstract

AbstractFor no‐tillage maize (Zea mays L.) planted in sod, production usually involves the use of a contact herbicide to chemically mow or kill the grass sod. Such a procedure often necessitates costly forage reestablishment and subjects the land to water and wind erosion hazards during noncrop periods. Substantial acreage of rolling, erosive land presently is being row cropped. Field studies on different soil types were designed to investigate: a) the feasibility of chemically suppressing the grass sod for maize production; b) maintaining a sod cover for erosion control; c) providing sufficient forage for fall and winter animal grazing.More than 20 treatments involving growth retardants and sublethal herbicide rates were evaluated for maize production in tall fescue (Festuca arundinacea Schreb.) and Kentucky bluegrass (Poa pratensis L.) sods at two southern Illinois locations from 1975 to 1977.The growth retardants which resulted in the best combination of maize yield and grass production in these experiments were maleic hydrazide (1,2‐dihydro‐3,6‐pyridazinedione), fluridamid (N‐[3‐[1,1,1‐trifluoro methylsulfonyl) amino]‐4 methylphenyl]acetamide), and mefluidide (N‐[2,4‐dimethyl‐5[[(trifluoromethyl) sulfonyl]amino]phenyl] acetamide.The herbicides which most nearly met experimental objectives were glyphosate (N‐(phosphonomethyl)glycine), glyphosate plus atrazine (2‐chloro‐4‐(ethylamino)‐6‐(isopropylamino)‐s‐triazine), metolachlor (2‐chloro‐N‐(2‐ethyl‐6‐methylphenyl)‐N‐(2‐methoxy‐l‐methylethyl) acetamide), metolachlor plus atrazine, and dalapon (2,2‐dichloropropionic acid). In most instances, it was necessary to apply a band of paraquat (1,1′‐dimethyl‐4,4′‐bipyridiniumion) over each row for acceptable maize yield.In these experiments, it was possible to obtain good maize yields while maintaining at least 50% of the grass sod with little or no erosion observed. This method offers the potential for a combination of maize production and grazing on erosive land.