THE CITRUS WHITE FLY: FOOD PLANTS. 
37 
Ofte/VGE TREES 
OR/INGE 
TREES 
It has been frequently observed that when the citrus white fly is 
first becoming established in a grove, if China trees or umbrella China 
trees are near, adults often can be found on these when none can be 
found on surrounding or intervening citrus trees. In order to obtain 
a more definite idea of the relative attractiveness of umbrella China 
trees and citrus trees, 4 records were made by the senior author on 
the laboratory grounds (fig. 2) at Orlando. In observation No. 1, the 
count on citrus was 
n deon4t r ,™ JISEK* *££•**""** 
f, ' A I m S = STORAGE SHED, L = LABORATORY. 
C, and the observa- 
tions on umbrella 
China trees were 
made on 2 small 
trees located about 
6 and 20 feet, re- 
spectively, south- 
west of 4 A. These 
umbrella China trees 
were slender 2-year- 
old growths about 4 
and 5 feet high and 
together bearing 
about 40 leaves. 
Observation No. 2 
was made on grape- 
fruit and orange 
trees E 6, E 5, E 4, 
D 5, D 4, and F 3 
and two stems of 
the umbrella China 
tree cluster in space 
F 7 nearest to tree 
E 6. Observation 
No. 3 was made on 
tree A 4 and the 
nearest umbrella China tree sapling. This latter had been defoliated 
since observation No. 1 was made. Observation No. 4 was made on 
citrus trees D 7, E 6, E 5, E 4, E 3, and F 3 and on two stems of 
the umbrella cluster which had been defoliated since observation 
No. 2. The data obtained by the four observations are given in 
Table VII. 
Fig. 2. 
I 
5 
-Diagram of the laboratory grounds at Orlando, Fla. 
(Original.) 
