Integrated Weed Management Using Narrow Corn Row Spacing, Herbicides, and Cultivation

Abstract

AbstractPotential increases in corn (Zea mays L.) grain yield have led many producers to consider using narrow corn rows. Narrow row spacing is also thought to play a role in reducing weed interference through enhanced light interception by the crop. However, there is little information on how narrow row spacing and cultivation fit into an integrated weed and crop management strategy. The objective of this research was to investigate the potential for reduced herbicide amount (either through below‐label rate and/or banded applications) using narrow corn crop row spacing and timely cultivation. Field studies were conducted in 1995 and 1996 at the University of Minnesota Southern Experiment Station in Waseca. Corn was planted in 51‐ and 76‐cm row spacings. Within each row‐spacing treatment, plots were either cultivated or not cultivated. Eight herbicide treatments were applied to each row space and cultivation plot. Corn row spacing had little impact on giant foxtail (Setaria faberi Herrm.) and common ragweed (Ambrosia artemisiifolia L.) visual control, density, biomass, or height. Cultivation was the single most important variable in reducing the amount of herbicide used. Grain yield was not increased by planting corn in narrow rows. Increased grain yield and weed control reported in previous research studies using narrow row spacing may be due to the choice of hybrid, plant population, and weed spectrum present.