THE PARASITES OF PLANTS 



plants with a spraying pump. (See page 253.) (Copper 

 sulfate is poisonous, although less so than Paris green.) 



Oat Smut and Wheat Smut The oat smut or wheat 

 smut attacks the plant if the seed that is planted is 

 smutty. To prevent this, it is necessary to destroy the 

 smut fungi on the seed before planting. The best rem- 

 edy for this disease is formaldehyde. This is a chemical 

 that may be purchased at the drug store. One pound 

 of formaldehyde to fifty gallons of water will give the 

 proper strength. Soak the grain in this chemical for 



about twenty minutes, 

 and then spread it out 

 so that it may dry with- 

 out heating. 



It is probable that 

 farmers suffer a loss of 

 fully one-fifth of their 

 pats and wheat through 

 the growth of smut on 

 the grain. This loss 



FIG. 27- Making Bordeaux mixture. may be entirely pre _ 



vented by the use of formaldehyde as directed. The 

 same treatment will prevent potato scab. (See page 255.) 



Parasites are Numerous. The harmful parasites of 

 plants are so numerous that we can not name them all 

 here. The methods used for destroying or preventing 

 insects and fungi are also numerous. The farmer and 

 the gardener may obtain books that name the leading 

 parasites that injure each crop, and that give the best 

 known methods of avoiding damage from them. It is 

 necessary to keep careful watch for harmful parasites, 



