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Soybeans
Volume 58 Number 12 Date 07/24/2014 SOYBEAN APHID - Densities remain very low for this time of year. None of the 81 soybean fields sampled as part of the annual survey that began last week contained an average count above 10 aphids per plant. Natural enemies were very active and abundant at most sites. As a reminder, foliar sprays should not be considered until the established threshold of 250 aphids per plant on 80% of the plants has been exceeded. Aphid counts have not surpassed this level in any soybean field surveyed by DATCP as of July 23. JAPANESE BEETLE - Soybeans across the southern half of the state are showing 2-20% of plants with light to moderate leaf injury by a combination of Japanese beetles, bean leaf beetles, grasshoppers, green cloverworms and various caterpillars. Leaf injury by these defoliators should not be allowed to exceed 20% between the bloom and pod-fill stages. GREEN CLOVERWORM - Larvae are beginning to appear in soybean fields in the southwest and west-central areas. Counts are currently below 4 per 100 sweeps. Those noted in La Crosse and Vernon counties this week were in the early and intermediate instars. Significant populations of this insect are sporadic and were last observed in 2010. -- Krista Hamilton, DATCP Entomologist 
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