OATS 



25 



or hot water as required, and by 

 first heating the oats for a few 

 minutes in warm water at about 

 120 F. ; for if the cold seed were 

 dipped into water at 133, they would 

 too rapidly lower its temperature. 

 This method requires the use of an 

 accurate thermometer. 



31. Insect pests. Insects are 

 the same as those of wheat, ex- 

 cept that the oat is not attacked 

 by the Hessian fly, and that 

 granary insects do less harm to 

 the oat grain, protected as it is 

 by its enveloping hull. A serious 

 pest of the oat plant in the West 

 and Southwest is the green-bug 

 (Toxoptera graminum, Fig. 9). 



FIG. 9. GREEN-BUG (Tox- 

 optera graminum) ; WING- 

 LESS ADULT. 

 Greatly enlarged. (After 



S. J. Hunter.) 



The green-bug is a plant-louse of green color and very small 

 size, that sucks the juices from the young plant. It has many 



natural enemies which, after the 

 early cool part of the season, 

 usually keep it in subjection. 

 One of these enemies, a lady-bug 

 beetle (Fig. 10), has sometimes 

 been artificially bred and dis- 

 tributed as a means of com- 

 bating the green-bug, especially 

 before the weather has become 

 warm enough to bring forth 

 FIG. 10. Two STAGES OF A LADY- naturaUy ma ny of the enemies 



BUG WHICH DESTROYS "GREEN- 



BUGS." f thlS P 6St - 



Right, adult beetle ; left, larva. Another parasite on this plant- 

 Enlarged. (After S. J. Hunter.) louse is a tiny four-winged insect 



