248 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 10 



direction the wind was blowing; a slight change of direction of wind 

 changed their course as readily. Many of the winged forms carried 

 larvae of Aphidnis testaceipes. 



Disappearance after Devastation 



The oats being dead and wheat heading, with the leaves drying up, 

 there was very little left for the bugs to live upon ; thus they destroyed 

 themselves. During the last days of May and early June the weather 

 warmed up and also continued dry. The bugs, having killed down 

 their preferred food plant, were necessarily precipitated upon the soil. 

 What would become of the hordes of wingless forms was a question of 

 considerable importance. The winged forms had flown away to other 

 fields, especially to the corn and kafir adjacent. Whether the hordes 

 of wingless forms could reach the corn and kafir depended on their 

 durability for long hikes; but fortunately they were too frail and read- 

 ily succumbed on the heated surface of the soil. 



The End of the Outbreak 



During the last week of June and first two weeks of July, we made 

 some long auto drives in southern Kansas and Oklahoma, observing the 

 disappearance of the pest. A very few small fields of oats had been 

 harvested, many had been planted to kafir and fetereta. The oat 

 plants being dead, the bugs had necessarily died or left the field; 

 wherever a green plant could be found, also a few aphids could be 

 found. Wheat which had not been devastated was ripening; the bugs 

 had about disappeared from them. By the middle of July it was diffi- 

 cult to find one anywhere, and those so fortunate as to find a green oat 

 or wheat plant were being parasitized by Aphelinus semiflavus and not 

 by Aphidius testaceipes. Together with Toxoptera went Aphidius 

 testaceipes and the Coccinellids. The "green bugs" practically disap- 

 peared from this locality during the summer, and by late fall none had 

 been found in Sumner county, though we had authentic reports of 

 their appearance in McPherson and Cowley counties, Kansas. Thus 

 the end of the most disastrous outbreak of "green bugs. " 



In Kansas the devastation reached an enormous acreage, about 

 250,000 acres of oats and 100,000 acres of wheat being devastated, this 

 loss falling principally on four counties. The loss in Oklahoma was 

 even greater than in Kansas, being as complete in destruction and 

 covering a much larger area. The acreage of oats devastated has been 

 estimated at 350,000, the wheat 160,000 acres, with 75,000 acres of 

 wheat badly damaged, making a total of 600,000 acres of oats, 260,000 

 acres of wheat totally destroj^ed, and 75,000 acres of wheat badly 

 damaged. 



