44 MISC. PUBLICATION 273, U. S. DEPT. OF AGRICULTURE 
a small nest. Its work causes the foliage of cypress to turn brown 
early in the spring. It is distributed through central and southern 
California and often is found working with the cypress tip moth. 
BUD MOTHS 
Frequently the tips of branches on young and older trees appear 
to be killed, but on close examination it is found that the twigs are 
not injured and the damage is confined to the buds, developing 
needles, or terminal leaves. These are webbed together to form a 
case, within which a smooth, hairless, very active caterpillar is 
found. Work of this character is done by a group of bud moths, 
mostly belonging to the family Tortricidae, which are true leaf eaters 
and therefore belong to the group of defoliators (p. 78). Usually 
their damage is confined to the leaves at the tips of branches, but 
during epidemics the older needles on the branches.are also fed upon, 
and large forest areas may be completely defoliated and the trees 
killed. This group of bud moths, while it includes hundreds of 
species of only minor importance, also includes such conspicuous 
forest-tree defoliators as the spruce budworm, hemlock budworm, and 
lodge-pole pine needle tier. 
SAP-SUCKING INSECTS 
A large group of insects, such as bugs, aphids, and scales, belonging 
to the orders Hemiptera and Homoptera, and the mites and red 
spiders of the class Arachnida, which are closely related to insects, 
are equipped with slender beaks which they insert into the tender 
leaves or shoots of plants and feed by sucking the juices from these 
succulent parts. ‘These various insects and mites are more important 
in the orchard and garden, or to shade trees, than they are in the 
forest. A few species, however, do noteworthy damage to small 
forest trees, and a few are important enemies of larger trees. Since, 
on the whole, they are more apt to be found seriously affecting young 
trees than older trees, they are considered at this time. : 
On shade and ornamental trees they can be controlled through 
the use of such contact sprays as lime-sulphur, miscible oiis, or nico- 
tine sulphate mixed with soap solution. Under forest conditions, 
however, the use of such sprays seldom is practical, and so far no 
control work of this kind has been undertaken in western forests. 
KEY TO DIAGNOSIS OF SAP-SUCKING INSECT INJURY 
A. Trees appearing sickly, leaves or stems not chewed but yellowing or 
covered with small incrustations, scales, powdery or cottony tufts, 
or small, soft-bodied insects. Trees frequently dripping with sticky 
exudation or covered with black smut. 
1. Trees dripping with sticky exudation, black smut usually 
abundant. Colonies of small, soft-bodied bugs, usually 
with two cornicles or protuberances on rear of abdomen, 
appearing on leaves or tender stems____--__--~ aphids, page 45. 
2. Leaves yellowing in spots, or bent. Small tufts of cottony 
wax appearing on under sides of leaves 
adelgids and scales, pages 47, 49. 
38. Small, circular, oval, or elongated shells or scales on leaves 
or twigs. Black smut not usually abundant_____ seales, page 49. 
4, Leaves yellowing, covered with fine, nearly invisible webs or 
SUVery COMtING io So eee spider mites, page 51. 
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