THE CITRUS WHITE FLY: FOOD PLANTS. oe 
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 
made on 4 trees, viz, 
4A,4B, 4C, and 5 
C, and the observa- 
tions on umbrella 
China trees were 
made on 2. small ORANGE TREES 
trees located about 
6 and 20 feet, re- 
spectively, south- Nv. 
west of 4 A. These 
umbrellaChina trees 
were slender 2-year- 
old growths about 4 
and 5 feet high and S 
together bearing 
about 40 leaves. 
Observation No.2 
was made on grape- 
fruit and orange 
trees E 6, E.5, E 4, 
Wasa cand: 3 
and two stems of 
the umbrella China 
tree cluster in space 
F 7 nearest to tree 
E 6. Observation A Lim Sia ESAG) 2 SSD 
No. 3 was made on Fie. 2.—Diagram of the laboratory grounds at Orlando, Fla. 
tree A 4 and the (Ongmal) 
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, EF 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. 
O = ORANGE, © = GRAPE FRUIT, 
@ = UWMSRELLA TREES, 
SS = STORAGE SHED, L=LABORATORY. 
| OPANGE 
TRIES 
O 
lo 
O 
O 
O 
O 
© 
| O 
VEGETABLE 
GAADE/W 
VACANT LOT 

