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CORN, SORGHUM, SUGARCANE 



EUROPEAN CORN BORER (Ostrinia nubilalis ) - NORTH DAKOTA - First-brood development 

 ranges from egg to pupae in Cass, Barnes, Ransom, Richland, Sargent, and Dickey 

 Counties, Most in second and third larval stage. Egg masses ranged up to 64 

 (averaged 21) per 100 plants. Up to 36 (averaged 11) percent of plants infested 

 (shotholed) . Larvae ranged up to 168 (averaged 23) per 100 plants. (Kaatz) . 

 NEBRASKA - Adult emergence occurring in all areas of State. Egg masses less than 

 one per 20 plants in eastern counties. First-brood larvae 70 percent pupated, but 

 some fourth instars still present. (Roselle) . MINNESOTA - Second-generation moth 

 emergence started, will increase next few weeks. Moth emergence could last into 

 September. Potential for heavy second generation populations high. (Minn. Pest 

 Rpt.). WISCONSIN - Second moth flight begun in some advanced areas in southern 

 section; emergence not readily apparent at blacklight stations due to cool 

 nights. Moths more numerous in blacklight traps in eastern counties. First-genera- 

 tion larval damage becoming more apparent in some fields. Larvae in ear tips in 

 some sweet corn, much stalk breakage in some grain corn. (Wis. Ins. Sur.). 

 ILLINOIS - Second-generation moths laying eggs, hatch rapid in southern sections. 

 Moth emergence in central areas well underway, egg laying begun. In northern 

 section, pupation 52 percent and emergence 24 percent. Peak egg laying will 

 probably not occur for 7 days in central areas, 10 days in northern areas; could 

 continue 14 days or more. Cool weather slowed development. Heavier than normal 

 first-generation populations in southwestern and western areas increased 

 possibility of corn damage by second-generation borers. (Sur. Bui.), 



INDIANA - Second-generation O. nubilalis moth flights underway throughout State. 

 Light trap catches week July 19-25 : 124 in Tippecanoe County, 99 (sandy area) 

 and 168 (muck) in Porter County, 99 in Gibson County. These catches associated 

 with previous heavy second-generation infestations. Most corn in silking stage, 

 large quantities of pollen present. (Huber) , Adults observed in many fields in 

 west-central and northwest districts, with first-generation larvae and pupae, 

 (Meyer) , MICHIGAN - Moth collections totaled 219 at Monroe County blacklight 

 station, peak of 110 on July 23, Second-generation emergence started July 19 

 in Montcalm County, Growers can expect this second brood to string out with 

 limited numbers emerging and laying eggs until end of growing season. Higher 

 percentage of second-brood larvae will bore into cobs and stalks for winter 

 protection. Growers will also need constant controls on snap beans and peppers. 

 (Newman) , MAINE - Up to 10 percent infestation in some fields of sweet corn. 

 (Erhardt) . OHIO - Second-generation moths first caught in blacklight traps on 

 July 23. (Rings, Rose). Moth collections at Wooster, Wayne County, not increasing 

 rapidly. (Rings) . DELAWARE - Adults averaged 135 per night in blacklight trap at 

 Bridgeville, Sussex County. Larvae averaged 4.3 percent in untreated peppers, 

 no fresh egg masses found at Bridgeville. (Lesiewicz). WEST VIRGINIA - Damage 

 moderate statewide to early planted field corn. Damage heavy in one field in 

 Monroe County. (W. Va . Ins. Sur.). VIRGINIA - Less than 15 percent of cornstalks 

 infested in Nottoway, Dinwiddle, Sussex, Southampton, Nansemond, Isle of Wight, 

 Surry, and Prince George Counties. (Allen). ALABAMA - Several larvae observed in 

 cornstalks and ears from Russell County. This is a new county record. (Bice et 

 al.). 



FALL ARMYWORM ( Spodoptera frugiperda ) - TEXAS - Continues troublesome on sorghum 

 in Caldwell, Gonzales, Guadalupe, and Lee Counties. Moderate to heavy feeding in 

 whorls and developing grain in Knox County. Moderate in whorls, damage light to 

 moderate on isolated crops in Reeves and Pecos Counties. (Neeb et al.). OKLAHOMA - 

 Moderate to heavy in sorghum in Grady, Cleveland, Oklahoma, Kay, and Tillman 

 Counties. Averaged about 1 per plant in sorghum and 3 per plant in corn in 

 Tipton area, Tillman County. (Okla. Coop. Sur,), ARKANSAS - Feeding in whorls of 

 unheaded late sorghum becoming more general statewide J at noneconomic level, 

 (Boyer) , MISSOURI - Damage to late sorghum observed in southeast area. (Houser) . 

 Observations in late corn and sorghum in southwest area showed 2-67 percent of 

 plants infested with early instars, (Munson) . MARYLAND - First infestation of 

 season in 0.25 acre of sweet corn in Wicomico County. Averaged 10 percent damage, 

 required controls. Damage to late-planted corn expected within 7 days in central 

 areas. (U. Md., Ent. Dept,). 



