REGULATORY
HORTICULTURE
[Vol. 23, No. 2]
Entomology Circular No. 186
Pennsylvania Department of Agriculture
Fall 1997
Bureau of Plant Industry
Pine
Tube Moth,
Argyrotaenia
pinatubana (Kearfott)
Lepidoptera:
Tortricidae
Rayanne
D. Lehman
This minor pest of eastern white pine is best
recognized by the symptoms it produces (Fig. 1) rather than by the appearance of
the insect itself. Its damage is purely aesthetic and control is rarely
warranted.
Distribution and Hosts: Pine
tube moth occurs in eastern North America, from Canada south to Florida and west
to Wisconsin, throughout the range of its principal host, eastern white pine. A
related species, the jack pine tube moth (Argyrotaenia tabulana), causes
similar symptoms on jack, lodgepole, and whitebark pines in the Rocky Mountain
states and the Canadian provinces of Alberta, Manitoba, and Saskatchewan.
Identification: These small, slender moths have wingspans of
14 mm. Two off-white oblique lines are found on the reddish-orange forewings.
When the moth is at rest, these wings conceal the smoky-colored hindwings and
gray to tan body. This coloration effectively camouflages the moths when they
rest near unopened buds (Fig. 2).
The pale green larvae reach 12 mm at maturity.
Identification of pine tube moth is generally accomplished through symptoms,
rather than examination of larvae or adults.
Life History: There are two generations of pine tube moth each
year in Pennsylvania. Adults emerge from overwintering pupae in early- to
mid-April, about the time spruce spider mite eggs hatch (personal observation).
This is several weeks earlier than the May emergence reported in the
literature (Johnson and Lyon 1988). The second generation adults are reported to
appear in July.
Eggs are deposited on the needles. Upon
emergence, larvae spin silk and tie 5-20 needles together to form a tube. The
caterpillars lie within this silk-lined tube, moving to the open end to feed on
needle tips. When the tube walls (needles) have been eaten down to 1 inch,
partially developed larvae will abandon their tubes and begin constructing new
ones. First and second generation larvae are active from 91-246 and 1151-1514
growing degree days (base 500F), respectively (Clark
1993). When feeding and development is completed, larvae pupate inside the
needle tubes.
Damage: Pine tube moth is a minor pest of eastern white
pine. The damage caused is purely aesthetic and may even go unnoticed until the
empty tubes turn brown in late summer. Rarely, specimen white pines in a
landscape may appear ragged due to the action of this pest. Control is generally
not warranted and would be extremely difficult since the larvae are protected
inside the needle tubes.
References
Clark,
S. 1993. Using growing degree-days for insect pest management. Cornell
Cooperative Extension (Suffolk County) Fact Sheet #5. 8pp.
Ives,
W.G.H. and H.R. Wong. 1988. Tree and shrub insects of the prairie provinces.
Can. For. Serv., North. For. Cent., Edmonton, Alberta. Inf. Rep. NOR-X-292. 327
pp.
Johnson,
W.T. and H.H. Lyon. 1988. Insects that feed on trees and shrubs, 2nd ed. Cornell
Univ. Press, Ithaca, N.Y. 556 pp.