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CORN, SORGHUM, SUGARCANE 



EUROPEAN CORN BORER ( Ostrinla nubilalis) - NEBRASKA - Third instars beginning 

 to enter stalks in eastern areas . Infestations of 70-90 percent of early corn 

 common in most eastern areas, 20-70 percent in Clay County. Control activity 

 continuing with shortage of recommended granular products. (Roselle, Frank). 

 Borers ranged 5-25 per plant in 4 untreated cornfields in Knox and Pierce 

 Counties; 4 fields. Mostly first to last instars. (Keith, Berogan) . IOWA - Larvae 

 in 4 fields: 6 percent fourth instar, 88 percent fifth instar, and 6 percent 

 pupated. Third generation likely in 1971. (Iowa Ins. Sur.). MINNESOTA - Serious 

 throughout southern half of State. Overall infestations heaviest since 1950 's. 

 Many fields near or past control period. Mostly third instars and above in south- 

 central and southeast districts and mostly first instars in southwest and west- 

 central districts. Egg masses still light in southwest and southeast districts, 

 but egg laying ended in these districts. Borer survival heavy and as many as 10 

 larvae per stalk in some fields. Fields sprayed in Redwood, Fillmore, Brown, 

 Goodhue, Dakota, Olmsted, and Watonwan Counties. (Minn. Pest Rpt.). WISCONSIN - 

 Blacklight trap catches light at all reporting sites. Moths peaked about July 3 

 in eastern counties. (Wis. Ins. Sur.). MICHIGAN - Larvae damaged some field corn 

 in Isabella and Montcalm Counties. Little damage seen in St. Clair County. 

 (Ruppel et al.). INDIANA - Infestations ranged 0-24 percent in south-southwest 

 and south-southcentral area corn; 0-48 percent in south-southeast area. (Meyer). 

 KENTUCKY - Larvae in 10 percent of Hopkins County corn with 10-20 percent of 

 plants damaged per field. (Barnett) . SOUTH CAROLINA - Second-generation borer 

 infestations appearing throughout State. (Thomas). 



NORTH CAROLINA - O. nubilalis infestations ranged up to 28 (averaged 4) percent 

 in sweet and fielH^ corn in Harnett, Sampson, Bladen, and Cumberland Counties, 

 50 plants per field. (Hunt). VIRGINIA - Generally very light in southern Piedmont 

 and southern Tidewater areas. Infestations 5-20 percent in Prince Edward, Prince 

 George, Southampton, Greensville, Brunswick, Mecklenburg, Pittsylvania, and 

 Henry Counties (Allen) . Damaged 60 percent of stalks in some Carroll County 

 fields (Tabor, July 1). MARYLAND - Moths averaged 6 per night June 30 to July 6 

 in Queen Annes, Dorchester, and Worcester Counties. Infested corn on Eastern 

 Shore ranged 8-80 percent (late whorl to early tassel stages), in central areas 

 0-96 percent (early whorl to mid-whorl). (U. Md . , Ent . Dept . ) . DELAWARE - Adults 

 of first brood beginning to emerge in Sussex County July 5-6. Emergence now about 

 1 percent. (Burbutis). 



FALL ARMYWORM ( Spodoptera frugiperda ) - TEXAS - Heavy and localized on grain 

 sorghum in Jackson County. Light in whorl of grain sorghum in Glasscock County. 

 (Neeb, Cole). ILLINOIS - Appearing in whorl stage corn particularly in southern 

 section. (Sur. Bull.). 



SORGHUM WEBWORM ( Celama sorghiella ) - TEXAS - Light to heavy and widespread in 

 Jackson and Matagorda Counties. Larvae as many as 40 per head in some fields of 

 Jackson County. (Cole). 



CORN ROOTWORMS ( Diabrotica spp.) - MINNESOTA - Heavy rains and wind at Minneapolis 

 and St. Paul lodged many cornfields. Lodging in Dakota County, 90 percent in 

 field with 10 larvae per plant and 10 percent in adjacent rootworm-free fields. 

 From first instar to pupae in southeast and southwest districts. Larvae 6 per 

 plant in Lincoln County field. Highs of up to 12 larvae per plant in Winona and 

 Goodhue Counties. Adults early as larval development has been rapid. (Minn. Pest 

 Rpt.). WISCONSIN - Limited surveys in southern Dane and northern Rock Counties 

 revealed larvae one-fourth to three-fourths grown in volunteer corn, in peas, and 

 oats. Lodging of plants should become noticeable in southern areas. (Wis. 

 Ins. Sur.). ILLINOIS - Occasional D. longicornis (northern corn rootworm) and 

 D. virgifera (western corn rootworm) adult seen. Demonstrative plots for larval 

 c^ontrol indicated poorer results than expected in some instances. (Sur. Bull.). 



