Tulip Tree Leaf Miner (Sassafras Weevil)
Contact: Eric Day, Manager, Insect Identification Laboratory
August 1996
Tulip Tree Leaf Miner (Sassafras Weevil)
Coleoptera: Curculionidae, Odontopus calceatus
Plants Attacked
Yellow poplar, sassafras, and magnolia.
Description of Damage
Rice-shaped holes, about 1/16" result
from adult feeding. Mines, usually two per leaf are formed by
larval feeding. If they are both on the same side of midrib, one
is extensive, and the other dwarfed. If on opposite side of
midrib, both mines develop normally.
Identification
Small, blackish weevil, short and stubby, about
3/16" long.
Life History
Before bud break, weevils attack swelling buds and
make puncture-like feeding marks. Mating and oviposition occur
in May and early June. The eggs are placed in a 1/4" section of
midrib on the underside of leaves. This destroys that section of
the midrib, causing the leaf, in many cases to break over. The
newly hatched larvae move from the midrib into the mesophyll,
their boring action accentuating the midrib damage. The larvae
pupate in infested area of mine. The first adults emerge in
early June. The weevils then feed heavily on the leaves and by
mid-summer, enter a period of aestivation, which is continuous
though diapause in winter. Adults overwinter in leaf litter.
One generation per year.
Control
Adults can be controlled in July. Treatments during
May may be helpful in preventing oviposition. Larvae in mines
can be controlled with systemic insecticides applied during June.
Remarks
This has not been a common or widespread pest in
Virginia, although it has been serious in West Virginia, Ohio,
and western Pennsylvania.