Wednesday, November 18, 2009

IPM - Part 3

“The difference between the right word and the almost right word is the difference between lightening and a lightening bug” - Mark Twain

Integrated Pest Management – IPM (continued)

After a lot of searching, reading, getting confused, starting over, I ran almost ran out of energy. I’ll try to summarize the rest of my research. So hopefully I’m using the “right word” not the “almost right word” ----- or the completely wrong word ---- or omitting an important point. I’ve included a link in each section if you would like more information.

Mechanical Control of the Adult Beetle

Mechanical methods are very straightforward. Just pop the little buggers into a bucket of soapy water. (And hope they don’t fly away before they hit the suds.) It is suggested this be done in the early morning when they are sleepy.

Chemical control of grubs

It’s possible to reduce the number of Japanese beetles by attacking the larval stage if the insecticide is applied at the right time. (See part 1.)

One product advertised for Grub control is Grubex manufactured by The Scott Company.

According to Pesticide Action Network (PAN) the hazard warning label is: “III Caution” or slight toxicity.

The active ingredient is halofenozid which is listed as a “potential” groundwater contaminant. It is easy to apply with the proper spreader setting. One bag costs about $20 and covers 5,000 sq. ft.

Biological control of grubs
Milky Spore - Bacillus popilliae

Bacteria can also be used to combat grubs. Milky Spore Bacillus popilliae is specific for Japanese beetle larvae. The US EPA fact sheet includes a description of the active ingredients, its uses and risks.

Milky spore is found naturally in the soil and is not harmful to humans. It does not affect beneficial insects. On the downside, it is relatively expensive and may require application for 3 or 4 years before it is effective. But it may be effective for 10 years.

At Gardener’s Supply a 10 oz can of Milky Spore powder costs $39.95 and covers 2,500 sq. ft.

Nematodes - Heterorhabditis bacteriophora

Biological Control: A guide to Natural Enemies in North America,” Cornell University notes: Relative effectiveness depends on several factors. They have to be kept alive during shipping and application.

Nematodes are roundworms that have a very short “shelf life” Nematodes need to be kept wet and breakdown rapidly in sunlight and are effective in a narrow range of temperature. When used correctly they can be very effective

You can buy 1 million nematodes in Grub Guard (Steinernema sp. and Heterorhabditis sp.) at Gardener’s Supply for $19.95.

The biggest drawback to using nematodes seems to be the difficulty in application.

Grub Guard – is a manufacturer of organic fertilizers in Bradford Vermont. “Grub Guard nematodes are shipped alive and should be released into a thoroughly moist soil or growing media as soon as possible.”

Thirteen instructions for application, mixing and dilution are listed.
Bt - Bacillus thuringiensis

University of Virginia Extension lists several varieties of Bt. It would be necessary to find the right variety for grubs.

Bt occurs naturally in soil. Bt products are applied much like synthetic insecticides and treatments are inactivated within one to a few days in many outdoor situations. Repeated applications may be necessary for some crops and pests.

Bt products need to be handled with care. Inhaling dusts or mists may cause allergic reaction or if rubbed on the skin may cause irritation. It is advised that you wear gloves, long sleeves and long trousers during application and wash thoroughly afterwards.

There are several online sites that offer Bt products for sale.


This series of posts was really not about the Japanese beetle. As I worked on the series I tried to follow one pest through the IPM process as honestly, objectively and logically as I could.

The posts are really about the ease or difficulty of the IPM process.

Did I make this process harder than it needs to be? Am I missing something? I don’t know.

I learned a lot during the process. There are now more things that I won’t have to search out again. Somehow a great idea like Integrated Pest Management should be easier for the average gardener. I think it is worth the effort if we are truly concerned about the environment.

What are your thoughts about Integrated Pest Management?

(Comments, arguments, corrections welcome)


Kathy said...

No corrections. I am going to try putting Milky Spore down at work. I am thankful to have the budget to do so this year. I would like to save some antique roses that we have and I don't like using anything really toxic.



Marie said...

I think milky spore is the best solution. I've heard of good results. Good luck with the roses.
Thanks for the comment.

donna said...

This last summer was the first time I've really had a problem with pests in the garden. Makes me wonder what next year will bring. I'll have to digest all your information and be ready for any and all pests.

maría cecilia said...

Good morning dear Marie, lots of information very useful. Thank for coming to visit and for the tips for roses. I also make my own compost and use it a lot but never heard about spraying compost, I´ll try it for sure. Thank you.
Muchos cariños
María Cecilia

Marie said...

It's difficult to figure out what to do about pests. There is controversy at every turn about insecticides. Sometimes I believe we think too much.

Marie said...

I make an aerobic compost tea using an aquarium pump. Experts say it is of no use to the garden. I look at it as a way to stretch my limited amount of compost. It seems to work for me.

Tatyana@MySecretGarden said...

I like the mechanical way the most!
Very informative, helpful post. Thank you Marie!

Marie said...

I appreciate your comment and I'm glad your found the post informative.

The mechanical way is sure friendly to the environment. I can't help thinking about my grandmother. She probably would have said, "Japanese Beetles? They're no problem. I just knock them in the bucket of soapy water like this. Splat!" Then she would go merrily off to work.