A lot of great information there. Thank you so much, but so sorry you have the problem. I hope you're right that it was due to the screwy year, and that it never happens again.

Tom, what a gorgeous horse!

Wow, guess I haven't been here for awhile. There were quite a few responses to my post and I guess I am not the only one with this problem.i posted the following at DG and will repost it here. Just kind of an update:
I finally figured out that scorch is the name of the condition that is causing a die off of some of my iris plants. The first sign seems to be a brown dead leaf in the middle of a fan, and when you dig up the plant in an advanced state of scorch, you find that the roots have dried up although the rhizome is still hard and looks fine. I have seen this other years, but didn't really know what it was.
I had some irises that bloomed gloriously this year, and then they just quit growing. I thought it was just the drought so I have watered them a couple times this summer, but it didn't help the ones with scorch. When I dug them it smelled a bit like mushrooms? So I am wondering if it is some kind of fungus maybe. For now I am digging up the ones with this condition and cutting out any of the parts that are still good. New roots will form at the growing edge of a rhizome. So I am sort of experimenting with the sickies to see if there is anything to arrest the disease. Well at least it has cut back on my need for new iris beds!
It's kind of amusing how every year seems to bring something new to deal with as far as irises go! Just as I conquer one problem another rears up! Well guess I will check the group on facebook too. Thanks everyone...

OK I joined the FB group, but I have no idea how to find the discussion about scorch.???

It is somewhere in the iris lovers group discussion. I have seen it.

I planted some irises in a different bed last year, and the other day I saw some small round holes in the foliage. Also saw a bug with what looked like wicked pinchers on the plant. I am going to watch these and see if they develop scorch. With the middle leaf affected this way (it is brown when it starts to grow inside the fan - like a gift wrapped up in layers of leaves!) It is like something affects the very center of the plants, right down to the roots but not hurting the rhizome.
What really bothers me is that it might also affect daylilies, which are my second favorite garden addiction. Did I mention that a little green stripey worm ate all of the foliage off of all of my baptisias? New green is starting to appear on the branch tips, though, so they probably didn't kill the plants.
This has been a very strange year weatherwise. I went to Barcelona in mid March when the snow had barely melted, only to find out that the temp here had been 85 for days, warmer than Barcelona! Because of this fast forward on the temp I didn't apply merit to my irises, because I thought it wouldn't be effective. Maybe merit also kills the leaf hoppers or whatevers that spread the disease?

Sharon, are you absolutely positive it's scorch? In all my years gardening I've never seen it, and it's been such a strange year, a lot of people are having trouble with dying leaves on irises.

It does kill the daylillies just like Iris I only had 3 plants but they were 4 years old so good size clumps and they got the same look as the iris did I thought it can't be the same thing but when I pulled some of the foilage they pulled out of the ground just like the Iris bulbs with no roots.

As far as it not hurting the Rhizome because you don't see a hole or rot does not mean it is not harmed, the scorch kills the plant, it is a organism that has to have a host to live in the form of a insect (leaf hopper, Aphid) or other leaf peircing insect it feeds on the plant and then transmits it to another then another, I was told it is similar to the Dutch Elm disease that has destroyed much of the Chinese Elms, what it does is destroys the cells that transport the nutrients to the plant it basically starves to death.

Once again it has to have a host to survive that is why you need to destroy any plants that have it ,if you leave them in place and some may try to grow back again but when they do they will have the scorch growing with it and the cycle repeats the only way to get rid of it is to heat the bulbs above 110 degrees for multiple days and you would need a greenhouse or something to that effect to do it. That is why it is important to get rid of anything that you know is infected if left in place it will serve as a reservoir for further infection and it continues hopping from plant to plant. From what I was told the difficult part of this is determining what has it , there are plants that have not been infected long enough to know if they are infected yet so if left to long the insects will continue to transmit it.

I chose to remove anything that even looked like it had it, and dig and move anything that looked unaffected hoping that I got rid of all of the sick ones, I cut the foilage low on them hoping the leaf hoppers would chose other plants to feed on and leave the Iris alone ,it has been a few weeks since I got most of them moved and yesterday I was checking my field bed and 95% of what I replanted has started to root and re grow with know signs of Scorch but I found about 10 bulbs that showed no growth and no roots and I tossed them in the dumpster maybe Im a little paranoid but I would rather error on the safe side then let it get started again.I was told Merit will not kill the leaf hoppers they must be sprayed directly I tried a number of products from Home Depot (Sevin) is listed as one that says it will kill them but I think it must need to be in a higher concentrate than they sell because it did not work for me at all I am using a product called Demon and Talstar and those sprayed directly on them work within minutes. I hope you can get it under control it has certaintly opened my eyes.

Polly I hope you never do it really is a monster from what I read it is known to occur only through out the central US but has been more prevelant in Texas, Oklahoma,Kansas,Nebraska parts of MIssouri and to a much lesser extent Iowa and Indiana. Thats what leads me to think it has something to do with our winter weather knowing that it has to have a host (insect) to survive we just did not get cold enough to kill all the bugs this year. Which is why I think it made it this far North when very few cases of it have been reported in Iowa. I remember thinking how nice it was to work outside in January there was no frost in the ground and I got a lot of my roses and other dead foilage cleaned up and enjoyed getting my hands in the dirt again but with the heat and extreme drought we have this summer we certaintly paid a price for it.

After everything I have read, it sure does sound like scorch. So... a larger number of leaf hoppers because of mild weather would probably result in more than just the occasional case of scorch. If it is transmitted plant to bug to plant, that would mean that the germ originally came from an iris that I bought that had it in a not yet visible state. Does this sound right? And because I have tried to coddle these brown middle leaf plants for a few years there are a lot more reservoirs for a lot more leaf hoppers....In which case we are probably just sitting on the tip of an iceberg!

Yes, we're definitely paying for this past warm winter and faux spring.

I don't know, Sharon, where it would come from. Have you posted a picture on the Facebook thread to see if they could help you? I always thought scorch was very uncommon. But obviously Brad has it.

Sharon that is my question that Im trying to figure out is where did it come from, Paul thought my original infection could of came from 2 different kind of grasses called bermuda or Johnsons grasses they are both rhizomes like iris and my thinking is the leaf hoppers lived on it through winter and then moved on to my Iris, this is just theory no evidence but it makes sense, I live in the country and we have both of those two grasses the bermuda in particular so once again theres no evidence its tranfered from the grass but it made sense once I heard it. If you have had this for multiple years it may be something else, pull a couple of them and see if they have mold on the bulb Botrytis is known to stay in the soil and is much more common than Scorch it could linger for years.

I would of thought if you had scorch it would have all but killed them quickly depending on the insects spreading it,I had it go threw over a hundred different plants in weeks, it seemed to affect some different than others some half of the plant still looked green which is what made me original think it was a bad case of leaf spot but others there was nothing left but dead leaves with a mold look to it. I was told that it never went away in Oklahoma it was worse in some years than others but they never got completely rid of it, I want to think the difference between us in Iowa and Oklahoma is our winters would be much colder most years we hit -20 which would wipe out alot of insects versus the southern middle of the country would have much milder winters than us and they survive. As far as it coming from another Iris you bought I would hope that is not the case most of the ones I recieve have some roots intact and look to be healthy anything with Scorch, there is no roots or what is there is mush and you would know by looking at it.

I just read what seems to be a recent re-assesment of the cause of scorch in the book "The Japanese Iris" by McEwan. I tried to copy and paste the quote but evidently Google books doesn't allow this. It is probably a mycoplasma that is vectored by a leaf hopper and the transmission is directly from plant to leafhopper to plant, so evidently you don't need to worry about it contaminating the soil...That is a big relief.

Yes you should be able to assume that a new iris rhizome with roots would be healthy, but some people say they always remove the roots. Then you wouldn't be able to tell. And I just read somewhere that maybe the iris could have the germ before it was really visible, like aids, I guess! But the leaf hopper could still pick up the mycoplasma and pass it on...

Found a quote from Paul Black on the subject:
"The answer is an emphatic and unequivocal - dig it up and get rid of it. Trust me, I have vast experience with the beast. If it is scorch, when they dig them up, the roots will be shriveled; if it is frost damage, the roots will still be plump. It is an insect vectored disease which means it is spread by leaf hoppers and aphids. If left in place, the plants serve as a reservoir of infection. The insect feeds on an infected plant and spreads it to uninfected ones. It is just like Dutch elm disease and other similar "wilt" diseases. There are probably ones that are infected now that don't yet show symptoms but that will as time goes on. That is what makes it such a nasty disease. It can be spread from plants that one doesn't yet realize are infected - sort of like the latency period in AIDS. The only way to destroy the organism in the plant is to dig it up and heat it to about 110 degrees F for at least 24 hours. I would do this only if it is a plant that is of great value. If the plants are in lush growth, they stand as good a chance of rotting during treatment as recovering. Each of these gardeners has my utmost sympathy and empathy. One of the best solutions is to plant the irises among other plants as in a mixed border. There is nothing that disease likes better than to have all its victims lined up shoulder to shoulder. Mid-America Garden Paul Black

Forgive the pun but "it is Scorching in Kansas"! Region 18 Spring Tour hosts, Hutchinson Iris Club is also reporting scorch in their Guest Iris beds and are very concerned about it....
When scorch appears in a clump it spreads from rhizome to rhizome. If the rhizomes are connected, I first immediately cut and separate the afflicted rhizome from the others. The afflicted rhizome can be heat-treated by placing on concrete or asphalt in full sun and baked for a couple of weeks. They will look dead but when replanted they almost always live. You just lose any bloom that was already inside the rhizome. Jim Morris, Region 18, St. Louis, MO This expert advice, others, will appear in the next MIS publication The Medianite in the "Ask The Iris Vets" column. Persistent problem in the Midwest especially after a winter like this-too warm, hateful cold, dry = stress! Rita Gormley "

This is the thread about scorch. I'm not smart enough to link to it, but this should move it to the top...Arlyn

Thank you very much! Did you just reply to it? Duh!

Yup !...Arlyn

Thank you for bumping this thread.

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All my iris beds look this right now. (except for the one I cleaned up already) I thought that was sort of normal for this time of year.

The healthy plants at the left would make me very concerned with the ones on the right,

That was a picture Brad had posted earlier in the thread. So ignoring the healthy plants in the picture, my iris beds look like the bad half. With how many dead shriveled rhizomes I got this year, I'm a bit worried.