8 
THE COLORADO EXPERIMENT STATION 
are larger and loose or open and the caterpillars stay in them to 
feed. When the leaves within the tent are devoured, the web is 
extended so as to take in more foliage. These tents also appear 
later in the season than those of the following species. They 
will seldom be noticed before the middle of July. The adult in¬ 
sect is a white moth, sometimes speckled with black. See Fig. i. 
Remedies.. —The same as for the following species except that it is not 
practical to collect the eggs which are deposited upon the leaves. 
TENT CATERPILLAR. ( Malacosoma fragilis.) 
This insect also hatches as soon as the leaf buds open, and 
builds small webs in the forks of the branches. A large number 
of caterpillars inhabit a web or tent, which is increased as necessity 
requires. See Plate I., Fig i. 
Remedies. —While the foliage is off, collect the large egg-clusters 
which are stuck to small limbs. They are covered with a dark, spongy 
material and are quite readily seen, appearing as galls or swellings of 
the limbs. If this remedy has been neglected, spray with the arsenical 
mixtures (3, 4, 5, 6 8). While the tents are small they may be cut out 
and burned if on small limbs. If on large limbs they may be burned out 
with a torch. 
APPLE FLEA-BEETLE. ( Haltica sp.) 
The apple flea-beetle is a small inetalic-green insect, about an 
eighth of an inch in length, which jumps or drops from the foliage 
when disturbed. It is most abundant on young trees or nursery 
stock or sprouts. 
Remedies — Any of the arsenical mixtures (3 to 8] are effectual in de¬ 
stroying this insect or driving it from the foliage. It can usually be 
driven from the leaves by the application of dry substances, such as 
lime, ashes, plaster, etc., (30, 31). 
BROWN MITE. ( Bryobia sp.) 
The brown or clover mite is extremely small and its presence 
is usually first detected by the faded, sickly appearance of the 
foliage. See Plate III., P A ig. i. The trees appear to need more 
water. The mites feed upon the leaves but deposit their red eggs 
upon trunk and limbs. When very abundant, these eggs color the 
bark red, which is most often noticed during winter. 
Remedies —To destroy the eggs while the trees are dormant (during 
winter) use lime, salt and sulfur mixture (21); kerosene emulsion (14), 
quadruple strength; whale-oil soap (12), quadruple strength, or crude 
petroleum (16). To kill the mites during summer use kerosene emulsion 
or whale-oil soap of ordinary strengths. It is far better to treat the eggs. 
APPLE PLANT LOUSE. ( Aphis pomi .) 
A green louse curling the leaves of apple trees, most abundant 
