12 
INSECTS INJURIOUS TO SUBTROPICAL FRUITS. 
The sprayed block contained 121 bearing trees. These yielded 165 
loose boxes of oranges. The unsprayed block contained 152 bearing- 
trees, which yielded 162 loose boxes of oranges. The sprayed block, 
therefore, produced three more boxes of fruit, though containing 31 
less trees, than the unsprayed block. 
Experiment No. II. — A block of "Washington Navel oranges em- 
bracing about 5 acres was selected in the spring of 1910 and treated 
three times with a spray of commercial lime-sulphur (33° Baume). 
1 part to 75 of water, combined with blackleaf tobacco extract. 1 to 
150. A gasoline power sprayer was used and a pressure of 200 
pounds maintained. The first application was made May 4, the 
second May IT. and the third June 14. The first application was 
timed at a date when most of the petals had fallen. The second and 
third applications were made when the thrips became sufficiently 
numerous. An effort was made to keep the young fruit free from 
thrips until it was the size of an English walnut, as it appeared that 
this would insure a high percentage of clean fruit. 
Examinations and counts made of 92 loose boxes of sprayed fruit 
and 20 loose boxes of unsprayed fruit from an adjoining unsprayed 
i; check " block gave the results shown in Table III. 
Table III. — Injury to sprayed and unsprayed fruit by orange thrips. 
SPRAYED. 
Num- 
ber of 
loose 
boxes. 
Total 
number 
of oranges 
exam- 
ined. 
Num- 
ber 
sound. 
Number 
slightly 
marked. 
Number 
moder- 
ately 
marked. 
Number 
badly 
marked. 
Per cent 
of sound 
fruit. 
Per cent 
of slightly 
marked 
fruit. 
Per cent 
of moder- 
ately 
marked 
fruit. 
Per cent 
of badly 
marked 
fruit. 
92 
8,458 
4,995 ; 3,383 
68 
12 
59 
39.9 
1 

TNSPRAYED. 
20 1,69 
498 1,108 
65 
26 29.3 | 65.2 
3.8 ; 1.5 
The sprayed fruit shows a total of 10.9 per cent marked, while 71 
per cent of the unsprayed fruit was marked, and more seyerely. The 
amount of benefit due to the spraying was 30.1 per cent, which was 
considerably less than in 1909, due to the fact that the thrips were 
more numerous and infestation worse in 1909. The total output of 
oranges from Tulare County in 1910 was 50 per cent freer from 
thrips markings than in 1909. 
Experiments with Nursery Trees. 
Several blocks of young nursery trees were sprayed in the fall of 
1909 with commercial lime-sulphur. 1 to 75. combined with black- 
leaf tobacco extract. 1 to 150. By two thorough applications it was 
