"Some Guy" wrote in message ...

I'm not sure if the large, non-biting insects I see every summer
around this time are crane flys or gnats. They look like big
mosquitoes but they don't bite.

If they are crane flys, then what can I put on my lawn either right
now, or later in the fall, or maybe in the spring to kill the
leatherjacket larvae that will eat the roots? Will grub killer also
kill these buggers to?

Knats are tiny little things -sometimes regionally called nosee'ems cuz they
are so small. Craneflies, OTOH, look like mosquitoes on steroids.

Unless one has a serious infestation - more than 35 of the white grub larvae
per square foot - treatment is usually not warranted. Birds will get the
majority of them or reducing the watering schedule on your lawn can help -
they need moist soil to survive and if you live in a cool season lawn
environment, allowing the soil to go dormant in summer (as is the nature of
cool season grasses) is an effective option.

If the situation warrants, you can apply beneficial nematodes in spring once
the soil warms up. To my understanding, milky spore is not effective against
cranefly larvae, only Japanese beetle larvae.

http://whatcom.wsu.edu/cranefly/

pam - gardengal