Controlling Webworm Invasions In Your Lawn

Controlling Webworm Invasions In Your Lawn

Nasty; destructive; silent invaders.  They mightn’t be big, but they can do big damage.  When it comes to maintaining a beautiful home lawn, sod webworm is high on the list of hated enemies!

 

What is Webworm?

Sod webworm is the caterpillar of the webworm moth.  It is generally about 25mm long and has a pale green body with distinctive brown spots along its length.

Female webworm moths can drop up to 60 eggs per night as they fly over your turf and these hatch within 1 week… and that’s when the trouble starts!  The hungry larvae tunnel into the thatch layer of the grass and feed on the green blades close to them.  The complete lifecycle of the webworm is approximately 6 – 10 weeks, so several generations may be produced in a single season.

Adult webworm moths are slender-bodied and grey and have a wingspan of about 2.5cm.  They are most active at dusk when they can be seen flying low over the grass, especially when disturbed by traffic or watering.

What are the signs of Webworm invasion?

The first signs of a webworm problem may be small brown spots in your turf, which worsen as the summer progresses. Or it may be that you notice the grey-brown coloured moths flying low over your lawn at dusk.  Another common sign is an increased amount of birds feeding on grubs in your lawn.

If you suspect an unwanted invasion, the best time to look for the critters is early morning while the dew is still on the grass: sod webworm leaves a tell-tale silky substance on the grass which is very obvious before the dew evaporates.  If your suspicions are confirmed, take a torch and make a thorough investigation of the lawn after dark – the caterpillars are active at night and you’ll likely be able to see them munching away at your grass!

 

How can I control Webworm?

Diagnosis made, symptoms confirmed… now how to get rid of these nasty little beggars?!

Thankfully, this isn’t too hard.  And there are several effective methods you can choose from. Firstly, there’s the old ‘soap ‘n’ water’ trick: mix approximately 1 tablespoon of dishwashing liquid into about 3 litres of water.  Douse the affected areas of your lawn with a generous amount of the mixture and you should see the larvae emerging from their hidey-holes.  The soapy water should kill them, but if it doesn’t, ensure their demise with your trowel!

If this method isn’t successful, there are several different types of pesticides which can be sprayed onto the lawn to kill the larvae.  Because they are most active at night, it is best to spray the lawn at sunset to ensure that they get a good dose of the poison as they feed.  Follow the manufacturer’s instructions carefully and repeat as necessary.

 

For more information on controlling webworm in your lawn, call the team at Greener Lawns on 1800 473 363.  We love healthy, pest-free lawns and we’d love to share our lawn maintenance tips with you.

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