©  2020 The Ohio State University, College of Food, Agricultural, and Environmental Sciences, College of Food, Agricultural, and Environmental Sciences, Ohio Agricultural Research and Development Center, 2120 Fyffe Road | Room 3 Ag Admin Bldg. In mid-June or around 1000 growing degree day units, adults begin emerging from the soil. After this time, or in late April and early May, only trichlorfon may work but it needs to be watered in immediately after application. The grubs burrow 4 to 8 inches into the soil as cold temperatures arrive. Life Cycle: Japanese beetles have only one generation per year. Egg development takes approximately 8 to 9 days at 80°F to 90°F but may take as long as 30 days at lower temperatures. Unfortunately, these parasites do not seem to be reliable in reducing Japanese beetle populations below damaging levels. Products containing imidacloprid or thiamethoxam are effective when applied from June through August. Occasional introductions are made into more western states such as Nebraska, Missouri, Kansas, Colorado and Arkansas. Since then, Japanese beetle numbers have fluctuated from year to year. Signs of Japanese Beetle Damage Newly emerged females release a sex pheromone which attracts males. Adult beetles are most active in the afternoon in full-sun. Carbaryl (Sevin), clothianidin (Arena) and trichlorfon are three active ingredients that all provide meaningful curative control. We work with families and children, farmers and businessowners, community leaders and elected officials to build better lives, better businesses and better communities to make Ohio great. Phone: 614-292-6181, © 2020 | 2120 Fyffe Road | Room 3 Ag Admin Bldg. Adult females instinctively lay their eggs in areas with higher soil moisture content to ensure survival of their offspring. Population reduction. The life stages of the Japanese beetle are typical of white grubs. The Japanese beetle is a serious agricultural pest. Try to apply 3/8 to 1/2 inch of irrigation but avoid surface runoff. Grubs can also withstand high levels of soil moisture, so excessive rainfall or irrigation will not affect them. In mid-June or around 1000 growing degree day units, adults begin emerging from the soil. It has attractive looks, however, with bronze wing shields and metallic green thorax. Red and confused flour beetles are capable of breeding year-round in heated buildings. As the larvae mature, they become c-shaped grubs which consume progressively coarser roots and may do economic damage to pasture and turf at this time. The insect thrives in hot sunny summer weather so this year has been particularly good for the beetle but bad for farmers and gardeners. As larvae, Japanese beetles live underground, feeding on the roots of grasses and other garden plants. Revised:  6/14/2013 Biological control products include milky spore disease, insect-parasitic nematodes, and fungal pathogens such as Beauveria bassiana and Metarrhiizium. Once they reach maturation in summer, these new adult Japanese beetles come out of the ground and fly for miles, if necessary, in search of food. Japanese beetles like these come out in large numbers and are known to eat over 300 species of plants. CFAES provides research and related educational programs to clientele on a nondiscriminatory basis. They feed on foliage or flowers, and are a major pest of over 350 species of plants, including fruits, vegetables, ornamentals, field and forage crops, and weeds. Eggs hatch in about two weeks, after which grubs begin feeding on the roots of turfgrass and ornamental plants. We start the process as soon as we see the first Japanese beetle in June and continue until we see no more beetles. The turf first appears off-color as if under water stress. 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