You are here: PFRA Online > Shelterbelt Centre > Publications
Shelterbelt Centre Pest Leaflets
Prairie Tent Caterpillar
Hosts: Choke cherry, rose, and cotoneaster
Appearance and Life History:
Larvae emerge from eggs in the
spring, just as the leaves begin
to appear. The larvae have
blueish-grey sides, and
reddish-orange backs that are
interrupted with a white stripe
down the center. By early to
mid-July the larvae are full
grown, ranging from 40 to 50
mm in length. Moths emerge in
early August, depositing egg
masses containing up to 500
eggs each. The egg masses are
deposited on twigs and
branches and covered with a
greyish foam-like substance.
The Prairie tent caterpillar
completes one generation per
year.
Damage: Almost immediately
after the larvae emerge, they
construct tent-like webs in the
branches. Caterpillars feed on
foliage outside the tent, but
return to the nest during adverse
weather conditions. As the
larvae develop, the tents are
enlarged until they are unsightly
masses of webbing containing
excrement, casted larvae skins
and larvae. Defoliation is
usually confined to the odd
branch, but there have been
outbreaks where trees have
been completely defoliated.
Severely-infested trees may be
temporarily disfigured and
unsightly, but will not be
permanently damaged.
Control: Prairie tent caterpillar
damage can be reduced by
picking off and destroying the
egg masses on trees in late fall
or winter when they are easily
seen. Caterpillar populations
can also be reduced by
removing and destroying tents
on cool days when most of the
larvae are within the nest.
Chemical control of the pest can
be achieved using acephate,
Bacillus thuringiensis,
carbaryl, deltamethrin, or
malathion.
For more information contact:
PFRA Shelterbelt Centre
Indian Head, Sask. S0G 2K0
Phone: (306) 695-2284 or Fax: (306) 695-2568
|