40 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. 
In Plat Il of Table XXXVI, recording the 1909 experiments at 
Concord, worms were not so prevalent, the fruit on the unsprayed 
plat being only 53.05 per cent wormy and only about 31 per cent of 
the fruit dropping from the trees. (See Table XX XVIII.) This plat 
shows a much higher percentage (13.869 per cent) of the pears 
wormy at the side and stem. Also, if we examine Plat V of Table 
XXXIV, recording the 1910 experiments at Walnut Creek, we find a 
higher percentage of pears wormy at the side and stem, namely, 
11.699 per cent as against 8.198 per cent in the check block. Plat V 
received no treatment for the first-brood worms, but was sprayed 
once on July 4 just before the second-brood worms began to enter 
the fruit. The surface of the fruit was fairly well covered, yet the 
percentage of fruit wormy at the side and stem was greater than 
was that of the unsprayed block. In this case it will be seen 
(Tables XLIV and XLV) that there was more fruit on the trees at 
picking time in Plat V than on the trees of the check plat. Also 
there were correspondingly more windfalls from the trees in the check 
plat than from the trees in Plat V. 
All of the plats receiving the first spraying (soon after falling of 
petals) show a comparatively light infestation at the calyx, and those 
receiving the two early sprayings have very few pears wormy at the 
calyx. (See Plats I, II, III, and VII, Table XXXIV.) Those plats 
on which this first spraying was omitted have a greater percentage of 
pears wormy at calyx, although they received one thorough spraying 
just before the first-brood worms began to enter the fruit, which was 
some four weeks after the petals had fallen. (See Plats IV and VIII, 
Table XXXIV.) 
TaBLE XXXIV.—Degree of infestation and relative infestation at different places of 
entrance by codling-moth larve. Plats I to VIII, inclusive, Walnut Creek, Cal., 1910. 
| pee Le 5 : 
4 AG Relative infestation at differ- 
Degree of infestation. ent places of entrance. 
(eect aac Total Percent 
; number | Total per | _ | Percent- 
Plat. PeTInE. of wormy)| Total per vote Lee cent of eae Perens age of 
[OSI gectse Tse. || Camo | CVS pears te) © worms 
wormy vos wormy at of worms | worms entering 
} pears. wormy | side and (100 per entering at side 
| at calyx. ave. cent). | at calyx. Ariaistars 
Plat I, sprayed Apr. 
9, May 2, July 14... 3, 126 126 4.03 0. 223 3. 803 126 5.56 94.44 
Plat II, sprayed Apr. 
9 and May 2........ 4,415 472 10. 69 - 747 9. 943 472 6.79 93.21 
Plat III, sprayed 
Apr. 9and July 4... 2,477 506 20. 43 5.611 14. 816 506 27.47 72. 53 
Plat IV,sprayed May 
PieNobAhil yy: Sete oan a 4, 096 922 22.51 11. 621 10. 888 922 51. 63 48. 37 
Plat V, sprayed July 
, eee cs 2,248 | 1,976 87.90 76. 201 11. 699 1,976 86.18 13. 82 
Plat VI, unsprayed 
checks 2S eee 2,427 2,279 93. 90 85. 702 8. 198 2,279 91.27 8.73 
Plat VII, sprayed 
B20) ip! Ey eae 2, 128 | 693 32.57 9. 020 23.550 693 27.71 72. 29 
Plat VIII, sprayed 
May’ 22 ohose5 a. 5535 2,811 857 30. 49 14. 695 15. 795 857 48.19 51.81 
