In the Gulf Coast States the pitch-eating weevil is probably the most
troublesome insect pest of pine seedlings. No accurate figures are
available on the damage directly attributable to this pest, but
mortality losses are estimated to average about 30 percent in
susceptible areas. All of the southern hard pines and other conifers are
probably suitable breeding and host material for the pitch-eating
weevil. Its range overlaps that of the pales weevil, being reported from
Labrador, Canada, south to Florida and west to Texas. It occurs in
damage-causing numbers only in the Gulf Coast States.
Pitch-eating weevils breed in the roots of freshly cut stumps. The
adults burrow down through the soil, sometimes a considerable distance
from the stump, and lay their eggs in niches chewed in the root bark. On
hatching, larvae mine the inner bark, packing their galleries with
frass. Pupal cells are excavated in the sapwood, and a chip cocoon is
constructed from the excelsior-like material removed during the cells’
construction. Development time varies from six to ten months depending
on when the stumps are initially infested. Emerging adult pitch-eating
weevils feed by night on the tender bark of seedlings. Small irregular
patches of bark are removed, eventually girdling the seedling and
causing its death. The pitch-eating weevil exhibits a population trend
similar to that of the pales weevil, and is a threat mostly in early
spring and in the fall.
The most effective control for pine reproduction weevils is to wait nine
months before replanting or until the stumps in an area are no longer
attractive to the weevil. Chemical control can be used when such a delay
is considered impractical.