Nematodes

grub vs nematode

Besides bringing showers, April is typically the month that brings customers to the store in search of a solution for getting rid of grubs, mostly in the lawn.  Grubs can be cutworms that chew through the roots and stems of your perennials, leatherjackets which are the larvae of the European Crane Fly (those stupid looking things that bump into you because you’re in their flight path and they’re not changing it) which do damage to lawns or weevil larvae that eat notches out of your rhododendron leaves.  All of which are not welcome pests in most home gardens.

In the past we’ve drenched soils with poisons, sprayed insecticides to no avail, and tiptoed around at night armed with flashlight and collection bucket or just ripped up lawns in defeat, ‘paved paradise and put in a parking lot.  Ooooooo la la la la.’  Now the poisons are slowly being banned and we’re getting too tired to get up in the middle of the night so what solution is there?  Behold the mighty nematode.

Nematodes are unsegmented, bilaterally symmetric and triploblastic protostomes.  Yeah, I thought that would grab you.  Although I really don’t know what all that means I do know that they work.  In layman’s terms nematodes are earth friendly and naturally occurring microscopic worms and I do mean microscopic.  We sell a packet of 5 million contained in a bag about an inch square.  Now that’s small.

These little guys can pretty much control or wipe out an infestation of grubs in your lawn even though you can’t see them.  They carry bacteria in their bodies that are toxic to some insects, mainly grubs, and they seek out the insect and enter them through any natural opening.  Once inside they release their bacteria that kill the insect and they set up shop as a baby nematode nursery.  In the end the host insect is dead but has helped a new generation (in the thousands) of nematodes develop which, in turn, go out and find other insects to continue the cycle.

Nematodes are a great alternative to chemicals that are not only poisons but can contaminate our water sources, make us, our kids and any pets or wildlife ill or worse.  Besides, poisons kill off everything, even the good bugs.  Nematodes have no affect on any other earth dwelling creatures like earthworms; they just target the grubs.

So, how do you use nematodes?  Easy.  You empty part of the package into a watering can, agitate it frequently so the nematodes don’t settle to the bottom of the can and water them into the ground.  As they are sensitive to sunlight and heat it is best to apply them in the early morning or late evening and when the ground is moist so they have a chance to move down into the soil.

Nematodes are available when the danger of frost is past.  I have had customers raise an eyebrow and give me disbelieving look when I’ve showed them the nematode alternative but the ones who have tried it come back later to tell me, almost in shock, of how effective these microscopic worms were.  So, give it a try and come back and tell me your story.  Put these almost invisible workers to the task this year and you’ll be amazed at what they can accomplish.

Shirley Eppler

April 2008