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VARIEGATED CUTWORM ( Peridroma saucia ) - NEBRASKA - Unusually abundant in field 

 corn in Seward, York"] Polk, and Butler Counties. Light in most fields, but in 

 others ranged 1-3 per ear on 50-75 percent of plants. Most feeding on silks and 

 developing grain at ear tips. Ranged third to last instar. (Keith et al . ) . 



WESTERN BEAN CUTWORM ( Loxagrotis albicosta ) - NEBRASKA - Second to fourth instars 

 light, averaged less than 1 per 20 ears in 2 Hall County fields. No egg masses 

 observed. (Keith et al.). 



WESTERN CORN ROOTWORM ( Diabrotica virgifera) - MISSOURI - Pollinated corn in 

 northwest area averaged one adult per plant. (Thomas). Adults collected on corn 

 in Pike County by J.L. Huggans . This is a new county record. (Banning). UTAH - 

 Severely injured several hundred acres of field and sweet corn in Cache and Weber 

 Counties this season. Growers in Richmond area report damage was less severe in 

 1970, but yields were reduced. Much home garden sweet corn totally lost and field 

 corn yields only 33-50 percent of normal in severely infested fields in this area 

 of Cache County. (Knowlton, Roberts). WYOMING - Damage severe to corn roots; 

 lodged 40-70 (average 50) percent of corn in field near Douglas, Converse County. 

 Damage noted in 2 fields not previously having infestations in area. Adults 

 averaged 7-8 per plant. Much damage to corn in La Grange area, Goshen County. 

 (Burkhardt) . MONTANA - Tassel damage noted in field and sweet corn from Columbus 

 in Stillwater County along Yellowstone River through Yellowstone, Treasure, 

 Rosebud, Custer, Prairie, Dawson, and Richland Counties. Adults averaged 5 per 

 plant in Sweet Grass County field. (Pratt). 



CORN ROOTWORMS ( Diabrotica spp.) - WISCONSIN - Adults increasing in all corn- 

 growing ai-eas. Larvae, pupae, and new adults numerous on roots of volunteer corn 

 in Janesville area August 2. Average of 4 late instars, 6 pupae, and 6 new adults 

 noted in soil beneath each plant. Up to 14 adults observed on aboveground portions 

 of volunteer plants. Severe larval damage evident in some untreated fields in 

 corn for 2-3 years. Report from Iowa County reveals total loss of crop in field 

 planted to corn for second year, up to 12 adults per leaf noted. D. virgifera 

 (western corn rootworm) dominant throughout southwest quarter of State and in 

 scattered localities as far east as Dodge and Fond du Lac Counties. (Wis. Ins. 

 Sur.). INDIANA - D. longicornis (northern corn rootworm) adults appearing in 

 light traps in northern and central areas. (Huber) . MINNESOTA - Cool weather 

 slowed Diabrotica spp. emergence and adult activity. Most infested fields in 

 southeast , south-central, and southwest districts with 2-3 adults per plant. 

 Counts 10+ per plant in few fields in Olmsted and Mower Counties. (Minn. Pest 

 Rpt.). KANSAS - D. longicornis and D. virgifera adult averages per corn plant by 

 county: Leavenworth up to 11, Doniphan up to 4, Wyandotte up to 7, Johnson up to 

 4, Miami up to 2, and Franklin up to 2. In field corn surveyed in west-central 

 and southwest districts, maximum adult populations (mostly D. virgifera ) 2 per 

 plant (Lane and Wichita Counties) . (Bell) . 



CORN FLEA BEETLE ( Chaetocnema pulicaria) - MARYLAND - Infestations continue to 

 range 40-100 percent on field corn in Frederick, Kent, Talbot, and Carroll 

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



SPIDER MITES - UTAH - Tetranychus ui'ticae (twospotted spider mite) and Oligonychus 

 pratensis (Banks grass mite) most serious corn problem in Utah County (Horn) , 

 Emery County (Day), and Sevier County (Ogden) . COLORADO - 0. pratensis generally 

 light on corn in Arkansas Valley following control efforts and unseasonable 

 moisture and temperatures. Some fields south of La Junta and Rocky Ford in Otero 

 County show moderate to heavy populations and damage. (Schweissing) . TEXAS - 

 Moderate increase of O. pratensis in many fields of grain sorghum in preboot 

 stage in El Paso and Hudspeth Counties. Light in Pecos and Reeves Counties, many 

 grain sorghum fields in hard dough stage. Infestations in grain sorghum decreased 

 during past week due to cool weather and rain. (Neeb, Rummel) . KANSAS - Some 

 cornfields treated for what is probably 0. pratensis in western districts as far 

 north as Thomas County and insecticides used appear to be giving little control. 

 (Bell). 



