Pine leaf aphid infestation produces not only a general reduction in radial growth of white pine but also a modification of the normal pattern of annual radial increment along the length of the stem. The greatest growth reduction occurs in the lower stem with proportionately less in the midcrown area and least in the top. This appears to reflect the distribution of branch mortality which is greatest in the mid- and lower crown. Several defoliators studied by other workers produce the greatest effect on radial growth and on foliage survival in the tops of the tree.Stem elongation reduction occurs only after crown damage and aphid infestation becomes extreme. Lighter infestations are reflected, however, in reduced needle length in the year of attack followed by reduced branch elongation in the year following attack. The combination of stunted and normal needles alternating with stunted and normal branch internodes is probably a unique characteristic of pine leaf aphid damage.

Eucosma gloriola Heinrich is distinguished from E. sonomana Kearfott, a closely related species, by using differences in morphology and distribution. E. gloriola is notably smaller in alar expanse and in size of male genitalia. The distribution of E. gloriola follows closely the natural range of eastern white pine (Pinus strobus L.), while E. sonomana follows that of ponderosa pine (P. ponderosa Laws.).Eucosma gloriola overwinters in the pupal stage in the soil. Adults emerge from late April to mid-May in eastern and southern areas, and from late April to early June in northern areas. The insect passes through five larval instars within a pine shoot. Larvae emerge from shoots and drop to the ground in early July in eastern and southern areas, and somewhat later in northern areas.Symptoms of attack and injury by E. gloriola in two- and five-needle pines are distinct from those of other eastern shoot and tip moths. The destruction of leaders is the most important injury since stunted and deformed trees result from repeated attack.Large-scale chemical control methods as required in reforestation plantings of Christmas trees are difficult to achieve. Glypta sp. was the most abundant of five parasites reared from the eastern pine-shoot borer.

An experiment was conducted in the Lower St. Lawrence region of Quebec in 1978 to determine (1) the validity of aerial spray applications of aminocarb timed against emerging L2 larvae of the spruce budworm (Choristoneurafumiferana (Clem.)) as well as (2) the relationship of timing spray applications and success of treatment. Two successive applications timed at peak L4–L5 (regime C) gave better results than similar treatment at peak L2 and peak L4 (regime A). Reduction in larval population density, and the amount of foliage saved due to regime C were almost twice that obtained with regime A.

Volume 99THE CANADIAN ENTOMOLOGIST 765 other hand showed no significant difference from the laboratory strain in either series of tests, with a difierence of 12.2% (x' = 2.62, P > 0.1) and 3.7% (f = 0.19), respectively, for generations 1 and 4.These results indicate that both strains were reverting to a behavior pattern similar t o that exhibited by the laboratory strain. It is difficult to satisfactorily explain the development of the behavioral change exhibited by the experimental strains in the multi-cell systems or the selective pressures involved. It may have been that the modification in this behavior pattern was due to secondary effects of some other change that developed, but remained undetected. T h e only other difference that was found between these strains was a slightly lower rate of reproduction in parasites from strain I1 compared with strain I. T h e dynamics of the interacting population~ in the multi-cell systems, however, were different in the later phases of their existence. For this report it would be sufficient t o point out that the blowflies in system I developed an ability to move from cell to cell at a faster rate than those of system 11. This resulted in great fluctuations of the populations in system I and a corresponding greater amount of movement from cell to cell within the system (in preparation). T h e parasite strains, however, were examined for emigratory behavior and neither strain exhibited a tendency to move from cell t o cell faster than the other. T h e behavior pattern relative to the distribution of hosts attacked appears to be a hereditary trait.