﻿EFFECTS OK HONEYBEES OF SPRAYING FRUIT TREES 



15 



Table 2. — Results obtained by iceighing honevbees at Winchester, Va., 1915, to 

 determine the effect on them of sprayiuff fruit trees at the customary time 





Colony number 





Weight of adult bees (after spraying) on the dates specified 







April 

 30 1 



May 

 1 



May 

 2 



May 

 3 



May 

 4 



May 

 5 



May 

 6 



May 



7 



May 

 8 



1 



Ounces 

 43.25 

 22.00 

 40.50 

 37.75 

 30.75 

 40.75 



Ounces 

 34.00 

 17.75 

 34.00 

 31.50 

 24.75 

 33.00 



Ounces 

 32.25 

 14.00 

 33.50 

 27. 25 

 23.75 

 29.25 



Ounces 

 31.75 

 13.25 

 31.00 

 27.00 

 21.25 

 28.75 



Ou7ices 

 30.25 

 11.50 

 30.25 

 26.50 

 21.75 

 27. 25 



Ounces 

 29.50 

 10.75 

 29.00 

 26.75 

 19.00 

 25.50 



Ounces 

 29.50 

 11.25 

 27.50 

 24.50 

 19.00 

 27.25 



Ounces 

 28.50 

 10.50 

 29.50 

 23.75 

 17.75 

 28.50 



Ounces 

 26.00 



2. 



9.25 



3 



27.50 



4 



22.75 





18.25 



6 



27.25 





Total weight 







215. 00 



175. 00 

 40.00 



160. 00 

 15.00 



153. 00 

 7.00 



147. 50 

 6.50 



140. 50 

 7.00 



139. 00 

 1.50 



138. 50 

 0.50 



131. 00 





Daily loss 



7.50 











* Date on which spraying was begun. 



In 191G, at Winchester, from the time the trees were almost in 

 full bloom till all the petals had dropped, the weather was almost 

 ideal and the bees worked normally. Spraying was begmi May 5, 

 in the Liipton orchard; occasionally on that day a tree still having 

 50 per cent of its petals was spraj^ed, although most of the trees had 

 lost more than 50 per cent but less than 90 per cent of their petals. 

 On the same day a few bees were seen visiting these trees. On May 

 6 about 98 per cent of the petals had fallen from most of the trees, 

 but a few trees still bore 10 per cent of their petals. A bee was occa- 

 sionally seen visiting the large sprayed trees, but more were observed 

 on a few young trees of a later variety which had also been sprayed. 

 On May 7 a fewbees were still observed visiting the sprayed trees; 

 on May 8, when practically all the petals had fallen, only now and 

 then was a bee seen in the trees. 



On May 5 sj)raying was also begun I14 miles south of the Cooper 

 apiary, but no spray was applied nearer this apiary until May 8. 

 On the latter date, when more than 90 per cent of the petals had 

 fallen, sj^raying was begun in the orchards near the Cooper apiary. 

 On this date and during the three following days very few bees 

 were seen in the trees in these orchards, but they were common on 

 the sprayed dandelion and grape hyacinth under and between the 

 fruit trees. 



On May 8 spraying was begun 1 mile southwest of the Miller 

 apiary and on May 10 it was general in the Miller neighborhood, 

 but the Miller orchard was not sprayed till May 11. On that date 

 no petals were left on the trees and no bees could be seen in tlie trees. 



In regard to the dead bees counted in the bee traps before spray- 

 ing, those caught in traps Nos. 7 to 10 averaged 35 a day; those in 

 traps Nos. 11 to 14 also 35; and those in traps Nos. 15 and IG only 17, 

 making a general daily average of 31 dead bees per trap. After 

 .'-j>i'aying was begun, the dead bees caught in traps Nos. 7 to 10 

 averaged 23 a day; those in traps Nos. 11 to 14, 19 a day; and those 

 in traps Nos. 15 and 10, only 12 a day, making a general daily aver- 

 age of 19 dead bees per trap. It will be shown later lliat tliese Jig- 

 tires repre.sent only a small percentage of the mortality of the bees, 

 but it is believed that they nevertheless represent a true mortality 

 index of the colonies before and aftei" the spraying was begun. 



