INJURIOUS INSECTS. 95 



are very injurious to the very young- plants if allowed to have 

 their way, but when the plants are nicely started they do not 

 seem to be seriously incommoded by this pest. These beetles 

 are very small and move very quickly. The adult insect is 

 black, or nearly so; some of them lay their eggs near the 

 roots of the food plants, where the larvae do some damage; in 

 other cases the eggs are laid on the under side of the leaves 

 and the larvae mine into them and live between the upper and 

 lower surfaces. But their chief damage is as beetles, in 

 which form they pass the winter. A species of flea beetles is 

 sometimes destructive to potato vines. 



Remedies. Since these are biting insects, they are readily 

 killed by Paris green or London purple in the usual propor- 

 tions. If the plants are kept dusted with air slaked lime or 

 plaster, they are measurably protected from this insect. But 

 latter applications are greatly improved by adding- a little 

 poison to them. 



Leaf Lice or Aphides (Aphis sp.) The leaf lice, otherwise 

 called aphides, that live on plants have very much the same 

 general habits. They are all sucking- insects and increase 

 with great rapidity when their food plants are abundant. 

 They generally winter over in the egg stage. The summer 

 broods are often brought forth alive without the intervention 

 of the egg state. Kerosene emulsion and tobacco water are 

 the usual remedies but hot water and pyrethrum will also de- 

 stroy them. Leaf lice are eaten by the larvae of lady bugs 

 and they are also subject to attacks of parasites. When the 

 lice are coated with a meal-like covering that sheds water and 

 prevents their being wet by insecticides, they should first be 

 sprayed with strong soap suds to remove the mealy covering, 

 and then the insecticide may be applied successfully. 



Cabbage Lice or Aphides [Aphis brassicce.) These are light 

 brown insects covered with a floury substance. They attack 

 turnips, cauliflowers, rutabagas and similar plants, as well 

 as the cabbage. They work generally on the lower side of the 

 leaves where they collect most abundantly. They are most 

 numerous in dry seasons. The remedies for them are given 

 under the general head of leaf lice, but in addition to those it 

 is a good plan to burn or compost all the old cabbage leaves 

 and stumps, since the eggs winter over attached to them. 



