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Soybeans
Volume 59 Number 10 Date 07/10/2014 SOYBEAN APHID - Levels of this insect remain well below the economic threshold of 250 aphids per plant and over three-quarters of the soybean fields surveyed in the past two weeks still had no detectable population. Average counts at the sites sampled from July 1-9 were less than 13 aphids per plant and 29 per infested plant, based upon examination of 40 plants per field. Only 18 of the 87 (22%) had detectable infestations. The highest total count during the two-week period was 512 aphids on 18 of 40 plants in (12.8 per plant) in an Adams County field. Despite the low sample numbers, aphid populations could increase rapidly in flowering soybean fields and economic densities may develop before the end of the month. This pest requires consistent monitoring from now until the R5.5 stage of soybean growth in August. JAPANESE BEETLE - This generalist defoliator is appearing in soybeans, corn and other crops. Beetle populations can vary greatly between the field interior and border rows, emphasizing the importance of thorough inspection of all areas of soybean and cornfields before making control decisions. Soybeans can usually tolerate substantial defoliation without reduction in yield, although treatment is justified for fields with defoliation rates of 30% prior to bloom (R1) and 20% between bloom and pod fill (R1-R6). -- Krista Hamilton, DATCP Entomologist 
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