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SPECIAL INSECTS OF REGIONAL SIGNIFICANCE 



BEET LEAFHOPPER (Circulifer tenellus ) - CALIFORNIA - Survey late September shows 

 76 percent nymphs in Fresno County. In Kings County, nymphs very young. Treatment 

 started in Kern County on October 6. In San Joaquin Valley about 200,000 acres 

 of Russian thistle to be treated. (Cal. Coop. Rpt.). 



CORN EARWORM (Heliothis zea) - MICHIGAN - About 2.5 percent of late-harvested 

 sweet cherry peppers in Monroe County infested. Indicates new insect problem on 

 this crop, following end of control for second-generation Ostrinia nubilalis 

 (European corn borer) . (Sauer) . DELAWARE - Adult flights less than 1 per night 

 in blacklight traps in Sussex County. (Burbutis, Lesiewicz) . OKLAHOMA - Larvae 

 averaged 12 per 25 sweeps in alfalfa in Jackson, Tillman, Kiowa, Cotton, Stephens, 

 and Jefferson Counties. Adults common in most areas. (Okla. Coop. Sur.). 



GREENBUG ( Schizaphis graminum) - NEW MEXICO - Popula tions -light , but infesta- 

 tions scattered in sorghum in Roswell area, Chaves County. (Mathews) . 



SPOTTED ALFALFA APHID (Therioaphis maculata ) - NEVADA - Light on alfalfa breeder 

 plots at Reno, Washoe County. (Arnett) . 



CORN, SORGHUM, SUGARCANE 



EUROPEAN CORN BORER (Ostrinia nubilalis ) - IOWA - Infested 99 percent of plants 

 in 32 fields in Boone County. Borers 340 per 100 plants; 54 percent of shanks 

 tunnelled, 395.8 ears per acre felled as result. Population (56,938 borers per 

 acre) greatest since 1957. (Iowa Ins. Sur.). NEBRASKA - Populations declined in 

 northeast, increased in central district, as compared to fall of 1970 „ Plants 

 in northeast averaged 94.6 percent infested, 214.7 borers per 100 plants. Central 

 district had 84.6 percent infested plants, 526.9 borers per 100 plants. (Keith, 

 Berogan) . NORTH CAROLINA - Surveys show even distribution statewide. Heaviest 

 infestations in Coastal Plain area. Stalk breakage related to borers did not 

 exceed 2 percent in any area. (Hunt) . 



SORGHUM MIDGE (Contarinia sorghicola ) - MISSISSIPPI - Continues heavy in late 

 sorghum in Noxubee County. (Robinson). NORTH CAROLINA - Adults collected from 

 milo near Plymouth, Washington County for first of season. About 80+ percent of 

 heads destroyed in 6-acre field. (Van Duyn et al.). 



SOUTHWESTERN CORN BORER ( Diatraea grandiosella ) - MISSOURI - Percent infestation 

 by county as follows: Butler 23.2, Cape Girardeau 10,4, Dunklin 35.2, Mississippi 

 68, New Madrid 37.6, Pemiscot 29.6, Scott 40.8, Stoddard 24.8. (Munson) . 

 ARIZONA - In 1970, at this time many fields of sorghum in Pima County 50 percent 

 infested. Presently about 4 percent. (Ariz. Coop. Sur.). 



SMALL GRAINS 



FALL ARMYWORM (Spodoptera frugiperda ) - ARKANSAS - Outbreak, larvae up to 12 per 

 square foot of wheat in Ashley County; about 100 acres destroyed. Controls 

 applied to several fields. (Boyer) . OKLAHOMA - Small larvae heavy on wheat in 

 Jackson, Tillman, Cotton, Kiowa, Jefferson, and Stephens CountieSo Ranged up to 

 6 per 4 leaf plant in some fields. Ovipositing adults numerous. Some fields 

 sprayed 3 times. Heavy in Harper, Woodward, Osage, and Craig Counties; moderate 

 in Garvin County. Moderate on rye in Choctaw County. (Okla. Coop. Sur.)o 

 TEXAS - Damage decreased on small grains and grasses in Rolling Plains area. 

 Some damage continues. Noted throughout much of south-central area. Infested 

 coastal Bermuda grass, forage sorghums, lawns, and golf greens in counties 

 near Gonzales. (Boring, Cole). 



