Where did you get this method of borer control? I have never heard of it before and I have read alot on borers.
Would be great if it works. Can you share a little more background info on this?

K

I found the info on this old GW thread titled "iris borer question" - here's the link:
http://forums.gardenweb.com/forums/load/iris/msg0316235326951.html
The info was from phantomfyre - the 7th post from the top.
I used it last year and it seemed to help a lot.

I didn't check out the link above but here is a link that I had found last year. I bought my Bayer at either Walmart or Home Depot or Lowes. Got to make sure it is the season long with Merit.

Here is a link that might be useful: borer control

It's highly questionable as to whether this product would have any effect on iris borers. It is NOT a systemic so it would definitely not have any effect on them once they emerge from the soil/litter. Besides the fact that this is a use completely inconsistent with product labeling or intent, it is very likely that it has little or no effect on the emerging hatchlings.

Randallpink - I checked the info on the Bayer Season-Long Grub Control, and you're right in that it is not labeled a systemic. So I called Bayer's customer service for clarification, since the active ingredient -Imidacloprid - is the exactly the same as the active ingredient in Bayer's Tree & Shrub Insect Control, which IS labeled systemic. I thought maybe the systemic product had a special ingredient that caused the Imidacloprid to be absorbed into the entire plant.

The customer service rep told me that their season-long grub control is indeed systemic. It is systemic in the grub and also gets into the plants' (grass, etc.) systems. She said it is not labeled systemic because the EPA doesn't require them to label it as such.

BTW, I noticed a cool rebate offer anyone can download on the Bayer site - $3 off one and $6 off two products (excludes a few products). You have to send original cash register receipt & must be mailed in by 10/30/10.

I was just going from the labeling on the product,in checking deeper the active ingredient is in fact a systemic, that's what happens with government regs. it would be a lot better if mode of action etc. were on all product regardless of end use. It also seems that it is extremely toxic to earthworms, and to bees when applied as a spray. It always concerns me when customers want to use products in ways not intended or at rates not recommended or necessary. You did your homework and and it should be a good call. Happy Gardening maybe spring is finally here!

I used the same stuff last year for the first time on perennial geraniums that have always had a terrible time with black vine weevils, and on the irises. The difference with the geraniums was amazing!

Irises don't put out as many leaves as often as geraniums do, so even if you have cleaned up damaged leaves and killed the borers, you won't see a dramatic difference in the appearance of the plant. But geraniums put out leaves all season long, so I saw a pronounced difference between when the attacks started (and previous years) and later as the summer went on.

Just make sure the product has imidacloprid and that you only scratch it into the ground around the plants you are trying to protect.

There are other "grub control" insecticides out there which do not have this product in them. You don't want a contact insecticide, you want the stuff that is taken up by the roots into the plants, and then only kills bugs which eat that plant. That's what "systemic' means.

You have to be careful about how you toss aruond the word "systemic"if talking about insects. All pesticides kill by disrupting one or another "system" of the insect. Insects are like us, they have respiratory systems, digestive systems, reproductive systems, etc. Some insecticides kill by disrupting their nervous system, some by clogging their breathing apparatus (respiratory system) and some by fouling their digestive systems. Those pheromone traps work by using their reproductive systems to lure them into a trap. So any insecticide is "systemic" when you look at it that way!

What matters is how tightly you are targeting the poison--for that is what they are---to a specific insect. You only want to kill the one that is messing with your irises or roses or whatever, not everything that flies through the yard.