UNIVERSITY OF FLORIDA 
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3 1262 09244 6599 
INSECT CONDITIONS IN FJERTO EICO POR THE SPRING 01 1936 
By • 
G. IT. Wolcott 
Since the middle of December, less than 2 inches of rain has 
fallen in Puerto Rico — much less than the normal rainfall for this 
time of year, the effect on certain insects has "been very notice- 
able. The tobacco leaf miner ( Gnor i mo sc hema operculolla Zell. ) is 
destructively abundant in tobacco-growing districts that ordinarily 
escape injury entiroly. 
The effect of the weather on scale, insects is also very 
noticeable, especially in citrus groves of such rugged contour that 
entomogenous fungi ordinarily can be depended on for commercial con- 
trol. On some papaya trees that had been sprayed with miscible oils 
to control the T7est Indian peach scale ( Aulacaspis p ent ago na Targ. ) , 
what ordinarily would be commercial control was obtained, but even 
a very small survival caused complete reinfestation 2 or 3 months 
later. 
The yellow sugarcane aphid ( Sipha f lava Forbes), is generally 
supposed to be more or less effectively controlled by heav2 r rainfall. 
This winter and spring, when there has been practically no rainfall, 
the drought seems to have been effective in preventing even the be- 
ginning of field infestations, as none has been reported. An ex- 
tended search in the Isabela district failed to disclose any. 
The lima' bean pod borer ( Maruca testulalis Goyer) was de- 
structively abundant in lima and snap beans at Yauco and Isabela 
last fall. In a lima bean plot at Isabela, from which samples have 
been harvested this late winter and spring, not a single caterpillar 
has been found. _ During the winter, a light infestation by Fundella 
cistipennis Dyar'was noted. A normally heavy infestation by Stiella 
zinclcenella Treit. developed this spring. 
The onion thrips ( Thrips tabaci Lind. ) lias entirely destroyed 
many onion plantings. 
