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Soybeans
Volume 59 Number 8 Date 06/19/2014 SOYBEAN APHID - Surveys of V1-V4 soybeans found aphids in 10 of 47 (21%) fields sampled as far north as Jackson County. Densities ranged from 1-22 aphids per infested plant on 2-18% of plants based on 40 plants examined. A few individual plants in a La Crosse County field had counts of 70-88 aphids. Specific counties in which the aphids were detected include Dodge, Grant, Iowa, Jackson, La Crosse, Lafayette, Monroe and Vernon. Early colonies were also found in Crawford, Richland and Sauk counties during the previous week, suggesting that the aphids are already distributed at low densities across much of southern and central Wisconsin. BEAN LEAF BEETLE - Light defoliation was observed at 40% of sites surveyed in the southern two-thirds of the state. Despite widespread feeding injury, less than 8% of soybean plants were affected in the infested fields and very few beetles were found. Treatment specifically for this pest is seldom justifiable, but could be considered in the rare event that defoliation exceeds 40% or for populations of 39 or more beetles per foot of row during the vegetative stages. ROSE CHAFER - This beetle has been noted on perennials, field crops, and in home gardens since the last report. The adults deposit eggs in the soil that hatch into grubs that feed on the roots of grasses, weeds and garden plants. Defoliation is expected to increase during the next 3-4 weeks, especially in areas of the state with sandy soils. -- Krista Hamilton, DATCP Entomologist 
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