'garden insects. 33 



passed on the roots of various common weeds. Here they Hve 

 unobserved and indeed are not always readily found, but when they 

 transform to adults they leave the native food plants and swarm on 

 the more toothsome cultivated crops. The best means of control 

 so far de-\-ised is to keep the young plants covered with a thick coat 

 of Bordeaux mixture. This does not destroy the beetles, but in 

 some way acts as a repellent or deterrent, for they pass by plants so 

 treated. A spra\ing with Bordeaux mixture should be given at this 

 time for the prevention of diseases, at any rate, and to it should be 

 added a half-pound of Paris green per barrel to destroy the ever- 

 present Colorado potato beetle. A second spraying will also 

 usually be necessary for the latter pest as soon as the young grubs 

 have hatched from the eggs. 



Where one has but a small garden and does not have the facilities 

 for readily preparing Bordeaux mixture, some of the prepared 

 Bordeaux pastes now on the market might well be used, though 

 they are more expensive and slightly less efficient than the home 

 made mixture. 



With the pea vines come the large green pea aphides which often 

 become so numerous as to destroy the crop. This pest first came 

 to our attention in 1899 and 1900, when it practically destroyed the 

 entire crop of the Atlantic Coast States, involving a loss estimated at 

 S7,000,000 and causing a most extraordinary rise in the cost of 

 canned peas. Every year since then serious injury from this pest 

 has been reported from part of New England to garden or sweet 

 peas. Just where the first of these aphides come from in the spring 

 is a mystery, for their winter habits are not known yet in this latitude. 

 Farther south they are known to winter over on clover and other 

 legumes, sometimes becoming so numerous on crimson clover as to 

 destroy it and make necessary a migration to the pea \anes. Many 

 plant lice which reproduce throughout the winter further south 

 pass the winter in the egg stage here, and it is quite possible the eggs 

 of this pest may be discovered on some other winter host plant. 

 The injury done by aphides may be almost entirely attributed to 

 the method and rapidity of reproduction. A single female will 

 give birth to 110 or 120 young in INIaryland in the course of her 

 short life, and probably nearly as good a record could be secured 

 in INIassachusetts. Inasmuch as one of these voung becomes full 



