18 FUMIGATION OF APPLES FOR SAN JOSE SCALE. 
examination, two weeks after treatment, a total of 13 scales of the 
942 examined was regarded as alive. At the second examination, a 
month after treatment, all scales were plainly dead, being discolored 
and drying up. 
LENGTH-OF-EXPOSURE SERIES. 
In the second or exposure series it was desired to determine the 
effect on the fruit of various periods of exposure and also the effect 
of the treatments upon the scales. The variety employed was Bald- 
win, from the same orchard in western New York, and badly infested 
with the insects. The fruit was dry when treated and was placed in 
one-third bushel baskets. The fruit was fumigated November 13, 
1906, with results as shown in Table IV. 
TaBLe IV.—E fect of different periods of exposure on scales and fruit. Strength, 0.20 
gram potassium cyanid per cubic foot. (Exposure series.) 
| | Rate at which) Number | 
Experiment | Variety of Kind of potassium | Length of ex-) Wigele | Effect on | Effect on 
No.— | apple. | package. cyanid was | posure. | cares | seales. | fruit. 
| | TEAL. | counted. | | 
| | 
a | | | | | 
| | Gr. per cu. ft. | | 
ID Seneca er | Baldwin. .) 3 bu. basket. 0.20 | 3 hours......| 3,360 | Alldead...) No injury. 
Derr era |---do...... eeee dope eee 0.20 | 23 hours....-. iF OCS |B One Do. 
1B eee ee SAC ORS Soe nee ae dos 0:20 | 2hours------ 3 OA aed Oe leeeDos 
PAR eae oe fepeeesCG Kee Seats mene dors 0.20 | 13 hours....- Iai) 3 ClOssscse |- Do. 
i yee soe ie eee OBS 2ee2 eee = Costa 0.20 | 1+hours.....- BW esac. 6s sce Do 
li Soneexenaace lend OG seers Sane Goss Bee 0320) | Mihour-sese2 MUO SOM ass se Do 
17 fe eats |e GLOME eeacrs [ego Kola Bes Are 0.20 | 50 minutes. -} 1518s |e O mae Do 
iS pee era ee peer Obata ee Basak COs Qnene | 0.20 | 40 minutes. - 2 GIRS eC Oe estee Do 
OBrien = yo OS Seren omer Ose a2-= | 0.20 | 30 minutes-.| 2,185 |...do- Do 
DO meee et ce tl oe GO etal ease domsses- | 0.20 | 20 minutes. -! SC iltal eecl On eee Do 
| | 
——. 
It will be noted that all exposures were effective in killing the 
insects, as determined by the two subsequent examinations, without 
any injury to the fruit. 
PACKAGE SERIES. 
In the third or package series it was desired to determine the 
possibility of successfully treating the scales on apples in the original 
packages, but opened up in various practicable ways. Some of the 
fruit treated was but a short while from cold storage, and the con- 
densed moisture on the surface presented afforded opportunity to 
observe if this lessened the effect of the gas on the insect or contributed 
to injury to the fruit. Several varieties of apples were used, as Ben 
Davis, York Imperial, Baldwin, and Rhode Island Greening. The 
work of fumigation extended over the period from November 14, 
1906, to January 22, 1907, as stated more in detail in the remarks 
following the table. Table V presents the essential features of the 
tests, grouped according to varieties of fruit and character of 
experiment. 
