312 REPORT OF STATE BOARD OF HORTICULTURE. 



♦ 

 be nearly so effective as it is. It is thus a remarkable fact how much of our 

 success with a poison spray depends upon this habit of the little worms.* 



Never spray a fruit tree when it is in blossom — You can reach the insect and 

 fungous enemies just as effectively, and in some cases more so, either just 

 before or just after the trees blossom. 



Hov) many applications to malae — As has just been shown under a preced- 

 ing topic, it is necessary to success to get a dose of poison into the blossom 

 end of the young fruit soon after the petals fall, and before the calyx lobes 

 have drawn together. If no rains occur between the time of spraying and 

 the closing of the calyx lobes, then this one application will be just as effect- 

 ive, we believe, if it is thoroughly done, as half a dozen later applications. 

 The sole aim of the fruitgrower should be to have a dose of paris green in 

 that calyx cup when it is covered by nature. If rains wash out one applica- 

 tion, then spray again if there be still time before the blossom cavity is 

 covered. Usually the recommendation is to spray trees twice, once just after 

 the petals fall and again in a week or ten days, to catch the last worms which 



hatch. 



Many extensive experiments have been made to determine the number of 



applications it is necessary or profitable to make. In 1885, Forbes made 

 seven and eight applications, and the next year only one and two. His results 

 were equally as satisfactory from the lesser number of sprayings. This is 

 also the conclusion reached by Lodeman and others who have made compara- 

 tive tests. These results are what we should expect from the life-history 

 and habits of the insect. When the second brood of the worms hatch, the 

 calyx cavity is securely closed and the apples have turned down, so there is 

 scarcely any chance to lodge the poison where the little worms would be 

 liable to get it before they get into the fruit out of harm's way. Yet some 

 experiments in Oregon indicate that a few of the worms of these later broods 

 can be reached with the spray, and apparently enough of them to lead the 

 experimenter to conclude that even six or seven applications can be made 

 with profit. However, it is the unanimous conclusion of experimenters here 

 in the eastern portion of the United States, where there are only two broods 

 or less of the insect in a year, that two applications are sufficient, one just 

 after the petals fall and a second a week later. No definite date can be set 

 for spraying for the pest, as the falling of the blossoms will vary from year 

 to year in the same orchard. 



The important thing for the fruitgrower to do is to watch the blossoming 

 of his trees and the developing of the young fruit, and not depend on any- 

 thing or anybody else. Simply see to it that there is a good dose of poison 



*We have ncvcrfoiind any dead worms in the calyx eavity, and thus have no abso- 

 lute proof that thev are killed by the poison there, but Munson has recorded an experi- 

 ment in Maine which .strongly Indicates that this is the case. He found that out of 

 three hundred and forty-six wormy fruits borne on sprayed trees only one hundred and 

 thirty-three had boon entered by the worms at the calyx, while two hundred and thirteen 

 worms had entered at the side or base; and out of lour hundred and forty-nine wormy 

 fruits on unsprayed trees, two liundred and tifty-two were entered at the calyx, while 

 only one hundred and ninety-seven worms entered at the side or base. Thus the relative 

 number entering the i-alyx was more than doubled in the case of the unsprayed tree. 

 "The only plausible explanation would seem to be that the iwison lodging in the calyx, 

 had destroyed the !arv;c attempling to (Mitorat that end, while those entering the side 

 or base esciipi'd. The larva- of I he second l>ro(id were also exciupl/' 



