PESTS AND PARASITES 



325 



MASS OF* GYPSY-MOTH LARVAE WHICH HAVE COLLECTED UNDER A BAND OE BURLAP 



After the larvae are half grown they seek for shelter during the day, and will collect under 

 burlap bands in enormous numbers, where they can be readily destroyed 



is essentially true that the great mass of 

 the foreign insect enemies of orchards 

 and forests have come in on nursery and 

 ornamental stock, and might have been 

 kept out, in large measure, if an efficient 

 quarantine had been in operation. 



THESE IMPORTED INSECTS COST US MANY 

 MILLIONS OE DOLLARS YEARLY 



The codling moth, or apple worm, oc- 

 casions a loss, in cost of spraying trees 

 and injury to fruit, of 16 million dollars 

 a year ; the San Jose scale, similarly in 

 loss of product and cost of treatment of 

 trees, 10 million dollars a year ; the Hes- 

 sian fly, the most important enemy of 

 wheat, probably causes an annual loss of 

 50 million dollars, and in some years this 

 loss has reached the enormous total of 

 100 million dollars. The cost to this 

 country of the cotton-boll weevil, from 

 the very conservative estimate of Mr. 



W. D. Hunter, amounts to about 25 mil- 

 lion dollars a year. All these were im- 

 ported. 



The Argentine ant is destroying citrus 

 orchards in Louisiana, and has spread to 

 the orange groves of southern California ; 

 the alfalfa-leaf weevil, probably intro- 

 duced on packing of nursery stock from 

 Europe, has destroyed hundreds of fields 

 of alfalfa in Utah, and is spreading to 

 adjacent States. 



The gypsy and brown-tail moths in 

 Massachusetts and portions of other 

 New England States are now costing 

 those States, in expenditures merely in 

 efforts at control, not counting damage 

 at all, upward of a million dollars a year. 

 In addition to this, the national govern- 

 ment is appropriating $300,000 a year to 

 aid in controlling these pests along the 

 highways, and by this means check their 

 more rapid distribution. In spite of these 



