SPRAYING FOR CURCULIO ON APPLE. 199 
of late spring frosts, which served to concentrate the injury. Unques- 
tionably a part of the loss shown was due to the apple curculio, which 
was abundant in that locality. At the time of the first application, 
May 16, the petals had just fallen from the trees. The St. Joseph 
results present some points similar to those obtained the same year at 
Mount Jackson, Va.,—namely, that when the curculio is excessively 
abundant, satisfactory results may not be obtained by spraying. 
Plat I, which received 4 applications, shows only 50.10 per cent of 
sound fruit as against 4.05 from the unsprayed trees, representing a 
gain of 46.05 per cent. The single drenching application, given to 
Plat II, resulted in 36.80 per cent of fruit free from cureulio, a gain 
over the unsprayed block of 32.75 per cent of the crop. 
TaBLE C.—Results of spraying apples for the plum curculio, St. Joseph, Mo., 1909. 
Totals (ra ies 
+ Total | num- on Per- ae = 
at ; rats Tree | num- | ber of 7 jcentage|/-o- F 
APal Treatment. Variety. No. | ber of | apples ber of of sound] CeDtage 
apples. | pune- | PY | annles. ofsound 
tured. | tures. apples. 
Four applications Bordeaux mix- ae ; : 5 
I ture (44-50) plus 2 pounds ar- Ben Davis. -| ; To a be 2 55 pee SN 
-----l) senate of lead: May 16, June 9, A 31 157 844 2’ 012 46. 54 apa ae 
July 9, and Aug. 6. 298 = UES See 
4,950 | 2,470} 5,810 ].......- 50. 10 
One application. Drenched with Sa = 
ii arsenate of lead, 2 pounds to 50 dowsae { =, aden Pee ees . oS ae Paes 
gallons water, May 16. , it z SNS) ceo 
5, 788 3,658 | 9,290 }.......- 36. 80 
1 1,694 1,625 7,715 ty el EE = = 
PME MUO MSPTAVOGs ss so0s56 5005 s5s5-5ss5[52 oe doe saeer 2} 1,437] 1,398 | 8,577 2 AC yh Ores ae 
3} 1,358 1,284 | 5,275 AS: ee 
4,489 | 4,307 } 21,567 |-.--..-- 4.05 
The records above given in spraying apple orchards for the cur- 
culio are assembled in Table CI, which indicates, in average per- 
centages, the amount of uninjured fruit from each plat from the 
several localities, arranged according to the number of applications 
given. These experiments have extended over a period of several 
years and were made in various places, so that the results are not 
entirely comparable. Even when considering the results of indi- 
vidual experiments, a wide variation is seen in results from orchards 
which received practically the same treatment—for example, in the 
two orchards in Virginia sprayed during 1909. 
