SPRAYING FOR CURCULIO ON APPLE. 189 
Taste XCIII.— Tests of killing effect on the plum curculio of arsenate of lead sprayed 
on peach foliage and fruit, Georgia, 1910. 
Beetles dying in each lot. 
Lot 7: 
Lot2: | Lots: | nota: | LOE | rote: ) Lot 8: 
Date of death of Un- 3 rayed Un- g raved Un- Ss srayed Un- Sprayed 
beetle. sprayed tet & sprayed | ~ Poe sprayed | * ae sprayed eis 
twigs uf & twigs ihe twigs As twigs Aves 
- with us with a with af with 
wit Si with 7 with . with : 
Raina fruit and foliage foliage fruit fruit friend fruit and 
foliage. | foliage. only. only only only foliage. foliage. 
Condition on Apr. 17.| Lot 1. Lot 2. Lot 3. Lot 4. Lot 5. Lot 6. Lot 7. Lot 8. 
Motalduede:ss= 5. 2c. 7 47 10 50 2 37 2 £0 
DUIS Be Ae Seer gee BQN Ecosse OO) tee sees 46 9 AGy | eee. 
Mseaped): <<. =< .=--- a 1 3 Cal kage 2 a Mal econ econ 
Some feeding tests made by Mr. Johnson to determine the possi- 
bility of preventing the fall-feeding punctures of the curculio on 
apple are interesting: 
August 17, a branch of Baldwin apple tree bearing fruit, after 
spraying with arsenate of lead at the rate of 3 pounds to 50 gallons 
of water, was inclosed in a cage with 50 beetles. Twenty beetles had 
died by August 28. An examination of the apples showed 3 without 
punctures and 8 with punctures, as follows: Fruit No. 1, 5 punctures; 
Nor2.1+ No. o,14:,No.4, 15; No.5, 16; No.6,;28; No. 7,41; No. 8, 
49; a total of 175 punctures on the 8 fruits. 
The condition of a check branch bearing 8 apples on this date was: 
Fruit No. 1, 66 punctures; No. 2,14; No. 3,45; No. 4,18; No. 5, 26; 
No. 6, 58; No. 7, 23; No. 8, 63; a total of 343 punctures. None of 
the beetles was dead in this cage and the punctures were much larger. 
SPRAYING FOR THE CURCULIO ON APPLE. 
EARLY EXPERIMENTS. 
The first experiments of which we are aware, made to determine 
the value of arsenicals in the control of the curculio on apple, are 
those reported by Forbes in 1885, and already referred to (p. 181). 
In this work 8 trees were used, 4 of them being sprayed and 4 re- 
reserved as checks. Two of the trees were treated with Paris green, 
1 with London purple, and 1 with lime. Two applications were 
