INSECTS INJURIOUS TO GARDEN TRUCK 477 



became a most formidable foe, whose destructive work was 

 checked only when we learned to use Paris green. 



The beetles pass the winter in the ground, appearing in the 

 spring as soon as the potatoes begin to grow. When the insects 

 are abundant they may entirely destroy the young plants. 

 The eggs are laid on the leaves, and the larvae, which appear a 

 little later, also attack the plants. There may be two or even 

 three generations during the year. The insect has many ene- 

 mies, the most important of which are certain tachina-flies, 

 which lay their eggs on the larvae, and certain predaceous insects 

 which feed on the eggs or larvae. In small patches the beetles, 

 larvae and eggs may be gathered from the vines and destroyed. 

 Larger areas should be sprayed with Paris green or arsenate of 

 lead, most growers now preferring the latter. It is used at the 

 rate of three to five pounds to fifty gallons of water, the stronger 

 spray being used for the beetles, the weaker for the larvae. 



Flea-beetles (Epitrix spp). There are several species of 

 flea-beetles that occur in the garden, attacking almost all kinds 

 of plants. These are all small dark beetles that leap quickly 

 when disturbed. They pass the winter in leaves or rubbish 

 in the garden or along the fences, and early in the spring attack 

 the young plants as soon as they appear above the ground. 

 Particular damage may be done to potatoes by the minute 

 whitish larvae which sometimes feed on the tubers, making 

 discolored little holes in them that detract from their market 

 value. 



If the plants are thoroughly sprayed very early with arsenate 

 of lead most of the beetles may be destroyed. Bordeaux mix- 

 ture seems to act as a repellent, so it is often worth while to use 

 it and lead arsenate combined. When the tubers are infested 

 by the larvae they should be dug up as soon as they are mature 

 and exposed to the sun for a few hours before storing. 



Potato Stalk-borer (Trichobaris trinotata) . This is a small 

 whitish grub that bores into the potato stalks, weakening or 

 entirely destroying them. The pupa is formed in the vine 

 near the surface of the ground, and the small grayish snout 

 beetle, which issues a little later, remains there all winter. This 

 suggests an efficient remedy. The vines should be raked up 



