a 
Eggs are laid in the spring by overwintering females and the 
eggs hatch into both winged and wingless females. The wingless 
forms remain on the pine host and reproduce repeatedly. Some of 
the winged ones may fly to spruce where they settle on the needles, 
lay eggs, and die. Nymphs hatching from these eggs also soon die. 
Five generations per year have been recorded as far north as the 
Lake States (619). 
Trees in parks and recreational areas, ornamentals and small 
nursery stock may be seriously damaged by the pine bark aphid. 
The needles turn yellow, and small trees may be stunted or killed. 
Large forest trees are usually not seriously injured. 
The pine leaf chermid, Pineuws pinifoliae (Fitch), occurs in both 
Eastern and Western United States. Its range in the East coin- 
cides with that of its primary hosts, red and black spruce, where 
they grow close to its alternate host, white pine. The adult is 
scalelike, about 1.5 mm. in diameter, and bears a fringe of white 
hairs. 
The life cycle takes two years to complete. During part of this 
time, including the first winter, infestations are found entirely 
on spruce; during the remaining time, including the second 
winter, they are found on pine.® 
Infestations on spruce result in ‘the production of terminal com- 
pact galls which have the appearance of true cones and contain a 
single aphid in each chamber. These galls are of minor impor- 
tance except on ornamentals where they may be undesirable. 
Heavily infested white pines, especially young pines in planta- 
tions, may be severely injured. Needles turn yellow; growth is 
reduced; deformities are produced; and occasionally the trees are 
killed. Several outbreaks have been recorded since 1900, some of 
which spread over large areas before subsiding. 
Pineus floccus (Patch) feeds on spruce and pine, spending 1 
year of its 2 year life cycle on each. It produces loose, terminal 
galls on spruce. On pine, its effects are similar to those caused by 
the pine leaf chermid. Heavy infestations on spruce may kill the 
tips of branches, or they may cause an over production of laterals 
which lead to bushy, deformed trees. Damage to pine is usually 
not serious. 
Pineus similis Gillette produces terminal cone-shaped galls on 
Norway, white, red, black, Colorado blue, and Engelmann spruces. 
The galls are shorter and thicker than those produced by the 
Cooley spruce gall aphid and the chambers are intercommunicat- 
ing. Small white spruce growing in the open in Canada has been 
severely infested. P. coloradensis (Gillette) has been observed 
feeding on the needles of red and pitch pines in Connecticut. 
The genus Phylloxera contains several species which produce 
galls on hickories and pecan. These aphids do not produce waxy 
threads as do many other members of the family, but some of 
them may be covered with a waxy powder. Their galls vary from 
small disklike or buttonlike swellings, with central openings 
guarded by plantlike hairs or processes, to large, hollow, globe- 
like structures up to 18 mm. in diameter. 
® Lowe, J. H. 1965. Biology and dispersal of Pineus pinifoliae (F.). (Un- 
pub. PhD. thesis, Yale Univ., 104 p. illus.) 
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