... it could be a rhizoctonia or a sclerotinia type of fungal rhizome decay. Botrytis convoluta mainly occurs during damp cool/cold, stagnant conditions with temps 50 degrees or lower. Those type of fall and winter conditions frequently occur during the winter season in the Columbia Basin of Washington and NE Oregon. Also, for some reason -- areas that were once extensive grassland seem more prone to Botrytis occurences.

I've been through the same struggles....with the same disease....., and I understand what you're going through .

It has been raining steady, quite heavily along with wind from time to time. As much as I would like to inspect the irises, it won't do any good, as I won't be able to treat then until the rains stop and we get some sunny days. Besides, I have a cold and severe eye infection. I am just going to hope for the best.

Evelyn, get better quick, and take care of that eye!

Yes, get better soon, Evelyn.

Barbara and William ~ I am doing the best that I can. for your kind wishes.

Two broad spectrum fungicides we use . Are they available in the US or the equivalent in another brand ? The active ingredients is the key.

yes, the active ingredients - Iprodione (AquaFlo) and Strobilurin (Scorpio) are available in the U.S But those two named products are not available in the U.S and aren't listed as being effective against botrytis convoluta, probably because the two active ingredients haven't been tested against this particular pathogen but because of their systemic action they'd be very much worth investigating.
I appreciate the head up, and will do more research on these two active ingredients

I contacted the OSU (Oregon State University) Extension office and this link may be helpful to some of you -- (Brad?) It listed a new dual action fungicide that I haven't heard of before.
Pageant
https://pnwhandbooks.org/plant...

TBMan said:I contacted the OSU (Oregon State University) Extension office and this link may be helpful to some of you -- (Brad?) It listed a new dual action fungicide that I haven't heard of before.
Pageant
https://pnwhandbooks.org/plant...

This one should be really effective and worth trying. We have Boscalid over here which is also effective against mustard seed fungus. I was going it to use it as it's from a different chemical group and broad spectrum.

Pageant fungicide is available on Amazon for $139. per pound! Guess I won't be ordering any of that.

I saw your great post of preventing rot and you gave me a few idea's.
Thank you

I have botrytis this year for the first time that I know of (may have had it before and didn't know what was going on), on irises I ordered this last summer. I was just out in the garden to inspect the iris bed after the snow finally melted away and saw the fuzzy gray mold on several of the fan bases. The entire crown pulled out easily. Now I'm going to go shopping for a fungicide, but I have no clue what to get.

Scoop out the soft tissue and apply a 10% bleach solution, or sprinkle a cleanser with bleach, like comet onto the affected area. I wouldn't recommend digging up the rhizome this time of the year. I've heard you can use garden lime on it too, but haven't tried that.