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Herbert J. Hopen

Based on recommendations for commercial cabbage producers fourteen herbicides were labeled over the thirty year period of 1965 to 1994. The number of herbicide choices ranged from two in 1965 and 1982 to ten in 1993 and 1994. The ten herbicides labeled for use in Wisconsin in 1994 are clomazone, DCPA, glyphosate, metolachlor, napropamide, sethoxydim, trifluralin, oxyfluorfen, paraquat and pyridate. Thirty two candidate herbicides were evaluated in thirteen of the thirty years but have not been approved for use in cabbage production. State “emergency” and state “third party” labels will be discussed as a means to provide herbicides for specific grower uses. The efficacy of each of the labeled herbicides will be discussed as supported by field, greenhouse and laboratory studies.

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Herbert J. Hopen

Through cooperation of state agricultural research stations, U.S. Dept. of Agriculture-Cooperative States Research Service (USDA-CSRS) Interregional Project Four (IR-4), manufacturers and grower organizations, new herbicide labels for cabbage have been granted recently. Labels for the herbicides consist of national, regional, and state need and state emergency use labels. These herbicides provide adequate choices of labels for cabbage producers in the major commercial production areas. Starting with only three herbicides available in 1965 to a choice of 10 herbicides in 1994, growers can be more effective in control of weeds in cabbage.

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Jack E. Staub, Larry D. Knerr and Herbert J. Hopen

The growth and yield of three cucumber (Cucumis sativus L.) genotypes were evaluated in 1987 and 1988 using three planting arrangements and four weed control treatments. A monoecious, indeterminate, normal leaf cultivar, Calypso, a gynoecious, normal leaf size determinate × monoecious determinate F1 hybrid (UW 11234), and a gynoecious, determinate little leaf inbred line (WI 50476) were evaluated for fruit yield at a 30-cm equidistant (109,000 plants/ha), a 20-cm equidistant (242,000 plants/ha), and a 43-cm row (272,000 plants/ha) spacing. Weed control treatments consisted of an unweeded control, naptalam benzoic acid at 6.7 kg ae/ha, chloramben at 4.5 kg ae/ha, and the herbicides in combination. Although number and weight of fruit per hectare increased with increasing plant density, fruit weight per plant decreased with increasing density. Fruit harvested from plants in unweeded control plots were significantly smaller than those in herbicide-treated plots, and fruit yield of unweeded control plots was lower than in nonweedy plots in 1987. In 1987, plants in plots treated with naptalam produced smaller fruit than plants in plots treated with chloramben or chloramben plus naptalam. Although fruit yield per plant in 1987 was similar in chloramben plots with or without naptalam and generally higher than that of plots treated only with naptalam, fruit yields from naptalam-treated plants were highest in 1988. `Calypso' usually produced more and larger fruit than the determinate genotypes. Based on comparisons of fruit per plant under comparable spacings, productivity of WI 5047G was often lower and its fruit were smaller than those of normal leaf genotypes. Plants of WI 5047G may not attain the source capacity needed for adequate fruit growth before the onset of anthesis, thus producing smaller fruit. Chemical names used: (2-[(1-naphtalenylamino)carbonyl)benzoic acid (naptalam); 3-amino-2,5dichlorobenzoic acid (chloramben).