ENEMIES OF PLANTS 195 



sene, one gallon. Dissolve soap in hot water while still hot but removed 

 from fire; add kerosene and pump back and forth till it becomes a 

 creamy mass. If made properly the solution will not separate upon 

 cooling. When using, dilute with ten to fifteen parts water. 



Tobacco. The various forms of to- 

 bacco ejctracts as a spray or powder, are 

 the most useful against plant Uce. 



Pyrethrum is the dried and powdered 

 flowers of a certain Chrysanthemum, and 

 is useful against thrips and plant lice. As a 

 dust it is appUed while foliage is 

 moist. 



Poisonous Insecticides. 

 Use for chewing insects, slugs, 

 cut-worms, maggots, caterpillars, 

 and most insects called worms. 

 The most used substance for this 



t.^^ „i? . 1 . . A useful hand-ptiinp spray engine suitable 



type Ot control is arsenic. for large? spraying operations 



Arseifate of Lead. This sub- 

 stance is used, at various strengths, depending on the plant affected 

 and the insect working. It is now the most used remedy for cater- 

 pillars, slugs, maggots and worms feeding upon the foliage of plants. 



Paris Green. Has same use as arsenate of lead, but is not quite 

 s6 effective. 



Hellebore. This is procured as a powder. It is much less poison- 

 ous than arsenical insecticides and is very useful upon ripening fruits, 

 especially for the Currant worm. It is appUed when dew is on the 

 plants. For worms on Currant aijd Gooseberry bushes sprinkle 

 slaked hme very lightly. 



Slugs and cutworms are easily controlled by distributing a 

 poison bait over the geirden or in httle piles under the plants. Use 

 wheat bran mixed with a little Paris green or arsenic and some 

 syrup. Mix thoroughly and scatter about just after dark. 



DISEASES 



"Whenever the normal functions of plants are interfered with, the 

 plant is diseased," says Dr. Freeman of the University of Minnesota. 

 But many of the garden troubles are not true diseases. Plants become 

 yeUow because they are getting too much water or too little or, per- 

 haps, their roots are affected by some insect, or perhaps the soil is too 

 poor or too rich. Real diseases are caused by certain fungi and germs. 

 They affect parts of plants and may be prevented from spreading, but 

 the affected parts cannot be cured. 



