Published online by Cambridge University Press: 12 June 2017
Economical combinations of herbicides and hand labor for weeding sugarbeets (Beta vulgaris L.) in high and low weed densities were determined for irrigated production in the southern Great Plains. Ethofumesate [(±)-2-ethoxy-2,3-dihydro-3,3-dimethyl-5-benzofuranyl methanesulfonate] preplant incorporated, a 50:50 mixture of phenmedipham (methyl m-hydroxycarbanilate m-methylcarbanilate) and desmedipham (ethyl m-hydroxycarbanilate carbanilate (ester)] sprayed postemergence on small weeds, and trifluralin (α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine) incorporated at layby controlled pigweed (Amaranthus spp.) and kochia [Kochia scoparia (L.) Schrad.] with acceptable selectivity in sugarbeets. Sucrose yield was identical for all methods of weed control. Using herbicides did not lower, and in some cases doubled, the total cost of weed control in an area with a low weed density. On the other hand, effective herbicide combinations saved $298 to $966/ha compared to total reliance on hand labor in an area with a high weed density. Elaborate combinations of herbicides were not justified even with heavy weed density. The last few weeds remaining in a field can be most economically removed by hand labor.