Question
Hello
I have had a bumper crop of Japanese beetles this year.  I would like to know when is the best time to treat for grub.
I live in RI.
thank you

Answer
Grubs are an interesting problem.

The soil is TEEMING with Grub predators.  Yes, your Garden is a naturally hostile environment for these pests. Scientists who study them have found that Grubs do not seem to be of any consequence in Soil that has been left undisturbed over long periods -- older houses, for example, with established Lawns, or in fields or woods.

And yet when you take new construction, one of the first problems homeowners notice is Grubs.  And that's not just Japanese Beetles.  Several Beetle species seek a cozy spot under Grass plots in Rhode Island.  The Cirrus Imaging website posts some vivid photos of some of these Beetles.  Brown, Red, Black -- some of them very pretty:

http://www.cirrusimage.com/beetles.htm

But I digress.

What can you do about these Japanese Beetles and all kinds of root-munching Grubs?

First: DO NOT USE GRUBKILLER.

It makes the soil instantly hostile to BENEFICIAL microbes and insects.  You think you have a problem with Grubs?  Wipe out the Beneficials and you'll see some real problems.

It is August.  It is important that you take steps to keep this problem from repeating itself this next year.  See the websites for:

Buglogical:
http://www.buglogical.com/beneficialNematodes_control_soilDwellingPests/benefici...

Suburban Habitat, a California company:
http://www.suburbanhabitat.com/pd_beneficial-nematodes.php

and Gardens Alive!, a mail order specialist
http://www.gardensalive.com/product.asp?pn=2344

These are just two of the many retailers that specialize in Good Bugs that fight Bad Bugs.  There are Nematodes, Fungi and Bacteria that prey on Grubs in the most beautiful way.

Nematodes are microscopic parasites that live off Beetle Larvae -- little C-shaped worms you probably noticed under your Grass, the size of a thumbnail.  Some Nematodes are carriers of Bacteria that infect Grubs, make them sick and die of disease.  Many control not only Beetles but a list of other pests -- Cockroaches, Fleas, and/or Termites for example.

Note that even HEALTHY Grass has a fair (and benign) population of Grubs.  Otherwise, what would Birds eat for Breakfast?  This is not a problem.  Grubs have their place in the world; it is only when there are too many of them that you have anything to be concerned about.

Nematodes and other 'Benefiicals' are completely harmless to humans and other mammals, fish and birds.  Unlike Grub-X and other 'Grub Killers' that inflict painful collateral damage all around your house.

At my house, Beetles zero in on Roses, Hollyhocks and Strawberry leaves.  But they start in the soil.

Milky Spore Disease has been a popular treatment.  It may sound like a strain of Anthrax, but MSD is a simple dried bacteria just waiting to come out of hibernation and incorporate itself into the bodies of certain insect larvae.  Bacteria move from host to host in the soil under your Lawn, finding insects that dine on your Grass and flowers, leaving not a trace of toxin.  Which is better for your Birds, your Butterflies, and your Ladybugs.

For the next month, travel outside at night with a flashlight and knock Beetles you find into a bowl of soapy water, then discard.

I have read that traditional 'Japanese Beetle Traps' supposedly attract neighborhood Beetles and cause more trouble then they fix.  But in all honesty, I have never found that to be the case.  And this may be all the attention this 'problem' needs.  Otherwise, Biological Warfare will eliminate the enemy before you ever see them.  They can run but they can't hide.

Thanks for writing.  Let me know if you have any questions.