European Crane Flies
Yet another exotic insect has come along to plague us. Those large “mosquito-like” insects that
cluster on your porch in late summer especially in the evenings when the light
is on are crane flies. Don’t panic, they
don’t bite.
There are thousands of native species of crane flies that
feed on decaying vegetable matter and live near water. Only a few species have adapted to drier
environments and feed on grass roots and foliage. Two of these, Tipula paludosa (European crane
fly) and its relative T. oleracea (common crane fly) are emigrants from Europe that have made their way here through port cities
in the northeast and northwest.
Populations are firmly established on both coasts and in Ontario, and now in Michigan.
There are some significant differences in these very similar
looking pests. Oleracea has longer wings
and is a better flier while paludosa has short wings and doesn’t so much fly as
hop from spot to spot. Each female lays
about 200 eggs. Oleracea can complete
two generations per year as opposed to one for the paludosa. One might imagine that the oleracea would be
the most serious pest, but as they disperse farther, they don’t build up the
populations as quickly as do the poorer flyers.
European Crane Fly larvae feed on the roots and on damp warm
nights they will move to the surface to eat the blades of the grass plant. Damage to turf looks a lot like white grub
damage but a bit of digging will reveal a grayish larvae that has no legs as it
is a maggot instead of a grub. Healthy lawns will tolerate lesser numbers
without significant dieback. Fall
treatments are considered ideal as most of the feeding is done at that time by
the smaller and more controllable European Crane Fly larvae.
The 3rd
instar European Crane Fly larvae burrow deeper to escape the winter chill, but
may do some feeding during mild winters before rising back up in spring to
resume feeding before pupating. In June, the European Crane Fly pupae wriggles
to the surface and the adult European crane fly emerges leaving the tough pupal
casing behind either sticking up out of the ground in short mowed grass or on
the tops of blades in taller grasses.
If you see European Crane Flies or have any questions about
how to control them please visit www.owenlawncare.com
or call us at (800)-724-6680 to have one of our lawn specialists come out and
answer any of your questions or concerns. Thank you!
