Validation of four bioeconomic weed management models for sugarbeet (Beta vulgaris) production.

The performance of four sequential weed man- agement models that assumed either low or high risk was compared to the performance of two sugarbeet consul- tants, one who assumed low risk and the other high risk. Weed management recommendations were performed over one growing season at two locations, each with several levels of weed populations. Recommendations for preplant, postemergence, and layby herbicide treatments or late-season handweeding differed among the four weed management levels. The high-risk management level was labor intensive and the low-risk management level was herbicide intensive. Weed populations at harvest, recover- able sucrose, and net return above weed control costs were not different among the four weed management levels. Weeds can be controlled in sugarbeets by employ- ing weed management practices based on bioeconomic modeling. Nomenclature: Sugarbeet, Beta vulgaris L.