The boring Iris Borer

I have been "boring" into all the information I can find online about this pest. There is a beneficial nematode that supposedly does a good job of control - available at arbico organics, "Steinernema carpocapsae
I have also read good press for "garden shield" ...(?)
Removing all dead foliage is of course of prime importance, but the moth will also lay eggs on any type of debris near the irises...bricks, rusty nails, cloth, twigs, wire screen, etc. Only once in the study were eggs laid on fresh green leaves.
A sticky trap with the appropriate pheronomes would be nice, but I haven't yet found one. Like those fly traps they make? Work very well for flies....

Would you please post links to the articles and studies you found? I'd be very interested in reading them.

Laurie

These are the websites I made special note of:

www.cdn-iris.ca/borer.html

www2.oardc.ohio-state.edu/nematodes/default.htm

www.irisgarden.org

http://canada-gardens.com/2tallbeardediris.html

Not sure which info goes with which. Interesting.

I don't know how effective nematodes are especially in the colder regions, They need to be applied early in the Spring to be effective, but will die if the temperatures fall to below 50 . So with us Northern gardeners, its a catch-22.
I would love to hear from anyone who is from the North that used nematodes successfully.
Laetitia

Well, yesterday I became a battlefield triage nurse. The whole process of digging thru soaking in bleach, etc. is very time consuming, so I am doing it in stages. First - dig up the plants that look affected first. Quickly break the rhizomes apart (someone wrote "like opening a fortune cookie") and discard the ones that are infested (in a garbage sack tightly tied until burned.) Let the others stay in a pile (keep each plant separate) as you gradually inspect, bleach them. I just want to find those borers fast.

It's a good education (I guess!) and I am managing to save some fans of most of the varieties I have. I am concentrating on the newest ones that I planted last year first.
I did lose one whole planting of one that bloomed so prolifically this year. Well, one of myproblems has been solved for me - what to do with all the extra irises!

Just remember at this time of year you have alot of pupa already in the soil and they are hard to see (little brown dirt colored capsules). Just because you get all the active borers, be prepared to continue battle in the Fall, and in the Spring....
Put the Merit down.
Try to remove the dead or dying foliage in the Fall and Spring.
If you can do a burn of the iris bed in the Fall I hear that is very helpful.
Laetitia

I am curious to hear how you made out. I tried bleach at an 1:8 ratio and had little success. I tried a 1:5 and had a greater success but still limited.

Is the Garden Shield an organic product? I am not strictly organic but some organic gardeners may want to know that.

I am probably going to go the Merit route.

What do you mean about success with bleach? What is the bleach supposed to do? I think the bleach is just to keep the germs out of the cut rhizome, etc. I have soaked out a few of the borers with bleach, but mostly I am just discarding the ones with active borers in them. If you can see them in the rhizome, you know where they are. So just pitch them. Although I am experimenting with a few that have borers in them, to see if it is possible to save them in case I have one really special one someday. I am planting these in a specially marked place so I can keep a close eye on them.

I think I saw one of the brown pupas, but the borers are still pretty much in the iris.

I don't know anything about garden shield. I am redoing my iris plantings so that they are easy to clean and inspect. I will probably keep them separate from the other plants, just for ease of care.

Someone indicated the bleach would kill the borers. It does to a degree. It certainly does turn the rhizomes white.

This is another discussion: http://davesgarden.com/forums/t/511746/

I just threw out alot of rhizomes. I am trying to save my best ones. Fortunately in ths case, I only have a few prized ones.

Thanks for the information.