THE CITEUS THEIPS. 5 
25 cents per box. Although in seasons such as 1911 only a small 
percentage of the fruit is culled from this cause, in one instance an 
entire shipment of navel oranges from a 5-year-old, untreated 
orchard was refused at the eastern market, with the statement that 
the oranges were too badly scabbed to be salable. In several other 
orchards inspected that year from 1 to 2 per cent of the fruit was 
malformed as the result of thrips feeding. 
GRADE REDUCTION. 
The most important damage resulting from the feeding of thrips 
upon trees that have passed the period of rapid growth is the lowering 
of the market value of the fruit by unsightly scabbing and scarring. 
Although the eating quality of the orange is not affected thereby, 
its commercial grading is lowered considerably and the selling price 
correspondingly reduced. 
EXTENT OF DAMAGE TO ORANGES IN TULARE COUNTY. 
In 1909 more than 80 per cent of the oranges of Tulare County, 
Cal., were so damaged by the citrus thrips as to lower the grade ; in 
1910 the grading affected about 63 per cent of the crop, and in 1911 
about 65 per cent was affected. 
To calculate the loss due to grade reduction because of damage by 
thrips it is necessary to know the method of grading and relative 
value of the grades. In California oranges usually are packed in 
either three or two grades. In the 2-gracle pack the quality of 
the fruit of the first grade is about the same as would be obtained 
by placing together the first and second grades of the 3-grade 
pack, the quality being sufficiently lowered to include fruit which 
would be of second grade in a 3-grade pack. 
Taking the season of 1911 as fairly representative of recent years, 
returns received by different packing houses on a total of about 
358,000 boxes of oranges of all grades indicate the following price 
range between the different grades. First-grade fruit average 37 
cents more per box than second grade ; the latter-28 cents more than 
third grade. Receipts from several carloads of fruit shipped in two 
grades gave an average difference of 51 cents per box in favor of the 
first grade. Examination of thousands of boxes of oranges through- 
out the district from Mount Campbell to Porterville showed 31 per 
cent of the fruit to run first grade, 13 per cent second grade, and 23 
per cent third grade, so far as thrips marking was concerned. 
Statistics on the amount and value of the total orange crop shipped 
from the entire San Joaquin Valley in 1911 are not available, but 
from Lindsay and its tributaries, constituting much the largest 
single citrus section of the valley, 1,525 carloads, or about 591,750 
