linden and the others that are usually planted are practically exempt. 

 There are plant lice on all, but on only those mentioned is there 

 any habitual increase to an extent that makes them a nuisance. In 

 the garden, on most shrubbery and on ornamental plants generallj', 

 plant lice often become annoying, and even destructive. Cratmgus 

 is especially liable to attack, and the tips will curl, twist, turn black 

 and become very unsightly, if nothing is done to cheek the insects. 

 The apple, among the tree fruits usually planted in gardens, is the 

 only one that suffers- to any considerable extent. Of the small fruits 

 currants are most likely to be troubled, and among the flowering 

 plants roses suffer most. There is hardly a plant or shrub that may 

 not at some time become badly infested by plant lice, and the methods 

 of dealing with them should be known to all. 



Remedies for Plant Ijioe. 



Plant lice eat no part of 'the plant itself, and it is absolutely im- 

 possible, for that reason, to reach them with any of the stomach 

 poisons. Paris green, arsenate of lead and all other materials that 



Fig. 3. 



Apple plant lonse, winged form, showing the honey tubes near end of body. 



kill by being eaten are of absolutely no use against these little suck- 

 ing pests. They can be reached only by contact poisons, which act 

 through the spiracles or breathing pores at the sides of the body. 



There are two kinds of contact poisons : those that act mechanically 

 by clogging the pores and those that penetrate into the body and 

 poison directly. Soaps are clogging in character, and so are oils in 



