MISCELLANEOUS NOTES ON ORANGE INSECTS. 
By H. G. HUBBARD. 
THE RUST MITE AND NOTES ON OTHER ORANGE PESTS. 
CRESCENT CITY, FLA., September 15, 1881. 
Str: On September 1, I obtained the first specimen of a coleopterous 
borer in orange. I have since obtained two more from which I hope to 
raise imagos.* The borers were found in young trees budded three 
years ago. The larva had in each case begun in the dead end of the 
old stump above the bud. As these dead ends were only a few inches 
long, the borer entirely hollowed them out, and, after eating all the 
dead wood, descended a short distance into the living wood at the base 
of the budded stalk. There was always a copious exudation of gum, 
and in one case this had attracted an ant, which began to nest in the 
upper part of the gallery. Undoubtedly this borer does great harm 
when forced to bore into the living wood, and in many cases must cause 
the death of the budded part of the young tree. The obvious remedy, 
or rather precaution, will be to trim closely these ends of the stump, as 
soon as the bud has made a strong woody growth. This will be the 
second year after budding. 
Experiments with pyrethrum extract diluted with water, and applied 
to leaves infested with ‘rust mite,” have not. been successful, and the 
mites have not been killed. Probably the extract is not strong enough. 
I have continued to accumulate evidence of a connection between the 
presence of the mites on oranges and the subsequent appearance of 
rust. It is always possible to determine whether leaves have or have not 
been infested with the mite, although they do not remain upon a leaf 
longer than four or five days. The upper surface shows plainly the 
result of their attack in a fine wrinkling of epidermis. On the fruit 
there is a similar effect, and, in addition, the exuvie of the mites 
adhere to the surface for several weeks after the mites have gone. 
I.am now trying to determine how long a period elapses between 
the disappearance of the mites and the appearance of the rust. A 
number of bearing trees, on which all the fruit is bright, have been 
examined, and in all such cases no rust mites have been found, nor 
any traces of their having been upon the leaves. Trees upon which 
all the fruit is rusted invariably show the effects of the mites upon 
* Elaphidion inerme Newm. 
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