5 Ways to Kill Sod Webworms

5 Ways to Kill Sod Webworms

Sod webworms are nocturnal caterpillars which destroy lawns in August through November leaving you with brown dead patches of grass and nasty letters from your homeowners association.  Fortunately, there are preventive and post infestation solutions to your problem.  As always a regular watering and fertilization regimen specific to your species of sod as well as a team of highly trained lawn spray professionals help but in case you forgot you can take matters into your own hands.

REMOVE THATCH using a plug aerator, power rake, or a garden rake and good ole elbow grease.  The thatch layer of your sod gives the sod grass a layer of insulation and protection from colder temperatures.  However, a thatch layer thicker than 1/2 layer gives the sod webworm caterpillar a place to build his silky threaded home.  Dethatching your lawn once a year making the living conditions unsuitable for the insect encouraging them to live elsewhere.   You can easily rent a plug aerator or a power rake from your local hardware or construction equipment rental store.

BENEFICIAL NEMATODES such as Steinernema carpocapsae and Heterorhabdtis bacteriophoraare are worms which can be purchased and applied to the sod.  The nematodes are not harmful to humans or pets.  Because sod webworms are nocturnal and UV light kills nematodes it is best to apply them in the early evening after sunset.  This method is only effective in lawns which have not been treated with an insecticide within 60 days of application. Please read all manufacturer’s instructions for best results.

INSECTICIDES are also an effective way to kill sod webworms.  Insecticides which contain the active ingredient spinosad and are applied as the manufacturers label suggests can help kill sod webworms populations.

MICROBIAL BACTERIA  can be used to kill sod webworms.  Bacillus thuringiensis is a naturally occurring bacterium which poisons the stomachs of caterpillars but does not damage other insects.  This is best applied two weeks after the emergence of the moths.  This bacteria kills all caterpillars and is not recommended for people who have butterfly gardens.

OVER SEEDING in areas which are thinning or have been devoured by sod webworms can aesthetically benefit your lawn as well as protect your grass from sod webworms.  Rye grasses and fescues seed is infused with a natural fungus that worms don’t like the taste of and will kill sod webworms who try to feed. The fungus sticks around for as long as the grass does. These grasses are seasonal and used on golf courses when sod goes dormant to keep it green.  They will die with the first signs of summer’s heat.

So there you have it.  The 5 Ways to Kill Sod Webworms or you can always hire these guys to do it for you.