CHAPTER XXVIII 



WHEAT — WEEDS, INSECT ENEMIES AND FUN- 

 GOUS DISEASES 



The injury to growing wheat caused by weeds, insects 

 and diseases is surprisiilgly large. A very brief description 

 of those pests of greatest economic importance together 

 with the more important remedial measures are given in 

 this chapter. 



411. Weeds. — The almost universal occurrence of 

 certain species of weeds in wheat fields not only greatly 

 reduces the yield of wheat but in many cases the grain is 

 much reduced in quality on account of the presence of the 

 weed seeds. Three of these are of primary importance in 

 the cotton-belt and deserve special mention. These are: 



(1) Chess or cheat (Bromus secalinus) 



(2) Cockle {Lychnis Githago) 



(3) Field garUc {Allium vineale). 



Chess or cheat is an annual grass, growing to a height of 

 two to three feet. The stems are erect and smooth, ter- 

 minating in a loose, open panicle, the branches of which 

 are somewhat drooping. Its common occurrence in wheat 

 fields has led many farmers to believe that wheat some- 

 times changes into chess as it grows, a miracle which of 

 course never happens. Wheat and chess are not closely 

 related, belonging to separate tribes in the grass family. 

 The fact that chess often occurs in a wheat field where 

 clean seed was sown is accounted for by the great vitality 



334 



