WINTER NUMBER 45 
ANNOTATED LIST OF THE INJURIOUS AND BENEFICIAL 
INSECTS OF THE AVOCADO IN FLORIDA®* 
By G. F. MOZNETTE 
Entomological Inspector, U. 8S. Department of Agriculture 
INJURIOUS INSECTS 
Trialeurodes floridensis Q.—The Avocado White Fly. Like citrus, the 
avocado also possesses its particular white fly. This species attacks the 
avocado in the more protected growing sections as does the Dictyospermum 
Seale. It is smaller than any of the citrus white flies, possesses white wings 
and a pale yellowish body. The pupae are readily distinguished by having 
a characteristic fringe. It multiplies rapidly during the summer months, 
and causes sooty mold in considerable abundance where present. The 
avocadoes growing along the keys and ocean shore are more particularly 
attacked by this white fly than are those growing on the mainland. ‘Trees 
in the nursery which are more or less protected often become badly infested 
with this species. The species is present in Florida wherever avocadoes 
are grown. 
Tetranychus yothersi McG.—The Avocado Red Spider Mite. The red 
spider mite which attacks the camphor in the northern part of Florida, 
seriously attacks the avocado at certain times of the year. This is particu- 
larly true during the dry winter months. This mite, when abundant, gives 
a grove a very unsightly appearance, by yellowing and browning the foliage. 
It is the only red spider mite known to the writer which lives and performs 
its depredations on the upper surface of the foliage. 
Heliothrips hemorrhoidalis Bouche.—The Greenhouse Thrips. This species, 
which is so common in greenhouses in the northern states, attacks the avo- 
cado in Florida in the open, and is present in varying numbers throughout 
the year. It becomes seriously abundant in places on the approach of dry 
weather in the fall and winter, and is capable of doing considerable damage 
by causing defoliation. It works on the upper surface of the foliage as does 
the avocado red spider mite. It also attacks the fruit when it becomes num- 
erous. Like the white fly of the avocado it multiplies more rapidly in the 
orchards situated on the keys and beach places in southern Florida. 
Chrysomphalus dictyospermi, Morgan.—The Dictyospermum Scale is a 
small circular scale of a light brown color. It is particularly abundant on 
the avocado in the more protected places, and where the temperatures are 
more even. Especially is this true along the ocean shore and keys. It 
attacks the branches killing many of the smaller limbs, but when abundant 
may often kill the tree. 
Saissetia oleae, Bernard.—The Black Scale becomes particularly notice- 
able in avocado groves on the keys and ocean front, especially during the 
fruit forming period, by congregating in masses about the stems of the 
fruits. Here it produces honey dew which accumulates on the fruit in which 
the black sooty mold develops necessitating washing of the fruit. Fruits 
so attacked by this scale bear weak stems and invariably drop prematurely. 
It does not apparently become abundant on the mainland. 
Pseudococcus nipae, Mask.—The Cocoanut Mealy Bug becomes noticeable 
*Published by permission of the Secretary of Agriculture, U. S. D. A. 
