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field and sweet corn. Most Ostrinia nubllalls larvae first instar, many second 

 instars present. Few fifth-stage larvae detected in extreme southern Rock County. 

 Blacklight trap catches indicate peak moth flight occurred June 23-26 except in 

 extreme eastern and northeastern counties. Current warm temperatures favorable 

 for moth activity but collections declined indicating significant flights ended. 

 (Wis. Ins, Sur.). MINNESOTA - Infestations variable but enough heavily infested 

 fields found to signal possible serious problem. Economic level reached when 

 50-75 percent of plants infested. Heavy in scattered fields throughout southwest 

 district. Number of borers per 100 plants averaged 87 for district. Counts ranged 

 up to 634 per 100 plants in some fields. Surveys in south-central district showed 

 similar situation. Borers per 100 plants average 106 for district. Light in east- 

 central district, borers per 100 plants averaged 56. Only egg masses found in 

 west-central district. Moth emergence probably peaked. Limited checks in southwest 

 and central districts showed over 90 percent emerged. Moths light in blacklight 

 traps but numerous in fields. Egg laying not as high as expected. Heavy rains and 

 wind during nights may account for light egg laying. (Minn. Pest Rpt.), SOUTH 

 DAKOTA - Surveys on June 27 indicated adult emergence and egg laying in corn- 

 fields as far north as Flandreau, central Moody County, and egg hatch common as 

 far north as Dell Rapids, northern Minnehaha County. Economic damage continued in 

 southeastern counties. Percent infestation 100 in Clay, Union, and Yankton 

 Counties on taller corn, and from 80 in northern Minnehaha County to 50 in Moody 

 County. To date, several thousand acres treated in southeastern counties, primarily 

 with granules. (Kantack, Jones). Eggs and first instars in northern Moody County 

 and southern Brookings County. (Jones). Larvae 3-15 per plant in 40 acres of 

 grain sorghum 24 to 30-inches tall near Yankton, Yankton County. (Miller) . 



IOWA - Surveys of tallest corn for O. nubilalis in 6 southwest counties; leaf 

 feeding in top 3 leaves considered Infested. Percent infestation averaged 49.6 

 (ranged 12-96); borers per 100 plants averaged 211.6 (ranged 24-700). At one 

 location in Pottawatomie County, 70-inch corn showed 60 percent infestation. 

 Infestation averaged 48.75 percent in field in Webster County. Larvae had not 

 bored into stalks by July 1 in southwest area. (Iowa Ins. Sur.). NEBRASKA - 

 Controls still underway in east, northeast, and southeast districts. In some 

 cases, controls being applied too late, as many borers boring into stalks. 

 Averaged 30-40 phone calls per day for past 14 days. Few scattered reports of 

 infestations in grain sorghum. (Keith) . In Adams County, averaged 38 percent 

 infested; corn 40 to 50-inches tall. (Berogan, Roselle) . MISSOURI - Ranged 16-100 

 percent of corn plants infested with 2-5 borers per plant in 21 northeast area 

 fields. Mostly third and fourth instars. Pupae observed in early planted fields. 

 (Munson) . KANSAS - Up to 80 percent of corn plants in early planted fields 

 infested with second and third instars in Republic and Brown Counties. From 5-15 

 percent of larvae bored into stalks. Most larvae boring into mid-veins of leaves 

 near collars. Percent of plants infested ranged by county (fields per county in 

 parentheses): Douglass 6-18 (3); Brown 15-80 (4); Nemaha 25-30 (2); Republic 

 50-80 (4) . (Bell) . COLORADO - Adults less than 1 per night in blacklight traps in 

 Sussex County. First pupa of first brood observed on June 30 in sweet corn at 

 Bridgeville. (Burbutis, Lesiewicz) . 



BLACK CUTWORM (Agrotls ipsilon ) - COLORADO - Adults appearing in small numbers in 

 light traps in Weld County. TUrano, Hantsbarger) . ARKANSAS - Damaged few sorghum 

 fields in Randolph County. (Boyer) . MARYLAND - Second to forth instars damaged 30 

 percent of 28-acre stand of corn near Kennedyville, Kent County. Controls applied. 

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



CORN ROOTWORMS (Diabrotica spp.) - NEW JERSEY - Very few larvae of D. longicornis 

 (northern corn rootworm) found feeding on corn roots in experimentaT plots at 

 Bloomsbury, Hunterdon County. (Ins.-Dis. Newsltr.). MINNESOTA - Diabrotica spp. 

 egg hatch not reported in southern half of State. Larvae heavy only in Wright 

 County in one field west of Delano and another east of Buffalo. Former had 15-20 

 larvae per plant, latter 8 per plant. Sixty percent in first instar, 35 percent 

 in second and 5 percent in third. (Minn. Pest Rpt.). IOWA - Percent development of 



