STATE POMOLOGICAL SOCIETY. 139 



ARSENICAL POISONS IN THE ORCHARD. 



As is well known, about fifty per cent of the possible apple crop 

 in the Western States is sacrificed each year to the codling moth, 

 except in sections where orchardists combine to apply bands of straw 

 around the trunks. But as is equally well known this is rather a 

 troublesome remed3\ At all events, in Illinois, Professor P'orbes, 

 in a bulletin lately issued from the office of the State Entomologist 

 of Illinois, claims that the farmers of that State suffer an annual 

 loss from the attacks of this single kind of insect of some two and 

 three-quarters millions of dollars. 



As the result of two years' experiments in spraying the trees 

 with a solution of Paris green, onh' once or twice iu early spring, 

 before the young apples had drooped upon their stems, there was a 

 saving of about sevent3'-five per cent of the apples. 



The Paris green mixture consisted of three-fourths of an ounce of 

 the powder by weight, of a strength to contain 15.4 per cent of 

 metallic arsenic, simply stirred up in two and a half gallons of water. 

 The tree was thoroughly sprayed with a hand force-pump, and with 

 the deflector spray and solid jet-hose nozzle, manufactured in Lowell, 

 Mass. The fluid was thrown iu a fine mist-like spray, applied until 

 the leaves began to drip. 



The trees were sprayed in May and early in June while the apples 

 were still very small. It seems to be of little use to employ this 

 remedy later in the season, when later broods of the moth appear, 

 since the poison takes effect only in case it reaches the surface of the 

 apple between the lobes of the calyx, and i*: can onlj^ reach this place 

 when the apple is very small and stands upright on its stem. It 

 should *be added that spraying "after the apples have begun to hang 

 downward is unquestionably dangerous," since even heavy winds and 

 violent rains are not sufficient to remove the poison from the fruit at 

 this season. 



At the New York Experimental Station last year a certain num- 

 ber of tree's were sprayed three times with Paris green with the result 

 that sixty-nine per cent of the apples were saved. 



It also seems that last year about half the damage that might 

 have been done by the plum weevil or curculio was prevented b}- the 

 use of Paris green, which should be sprayed on the trees both early 

 in the season, while the fruit is small, as well as later. 



