Help with pest identification, please?

Alrighty, I expect to lose about 1/2 of my 220 varieties this first year due to climate here in the south. I've got my first rotter in the group, and I need help identifying the pest I found within. The iris is Viva Mexico and I purchased the rhizome from a grower in Mississippi. It is one of only two problem rhizomes at the moment, which I think is pretty good considering the tremendous rain and humidity we have had. The other problem rhizome, Broken Record, was damaged when received, so it was iffy at best. I believe these could be immature borers in the base of the Viva Mexico, but as I've never seen a true borer, I can't be sure. They could just be caterpillars. So... identification help, please? Thanks for any feedback you can provide! Ev :)

Iris borers should be out of the rhizomes and into the pupa stage by now
if the general info is accurate. Check the leaves for a nick in the edges
where the larva would have entered. Also, the rhizome may be hollowed
out or rotted. Other than that, I would have to defer to some of the more
experienced growers.

All the above may be moot in cases of your extended rain soaked season.

Yes, I realized that... but these were yellow when squished, not green. I thought cutworms were green inside, and I haven't seen any caterpillars like this before. I believe these guys may have come in with the rhizome from where I ordered them. I thought they most resembled the borer photos I've seen, but they are smaller. Anybody have more info?

Could be the larva was caused by the rotting and not the rotting caused by
the larva.

Doesn't look like borer. DH suggests cutting out the rot even into the rhizome--then try the 10-1 clorox treatment. It's worth a try & you don't want rot to spread. There are larvae which feed on rotting vegetation.

Advice is a lot cheaper than a large garden but, in this case, I would dig that
iris and any other showing any signs of rot and dispose of them. Then mix
a batch of 20% bleach/water and soak the immediate area where they were
planted. Some of the rot diseases can spread throughout the entire bed.

I am having an epidemic here, with all of this rain, but they are all new iris, with no bugs, I cut off the rotted part with a knife, and soak in 10% bleach solution, rinse well and let them dry til the injury is scabed over, then just incase I plant them in compost in pots til next year outside in the full sun, not the ground, I tried that one year and the ice and water just sat on the tops and I could not get them out of the ground.

I think I agree that they are maggots cleaning up the rot, not causing it.

I'd take a little different approach to not stress the plant any more by digging it up. I would scrape off all soft parts of the rhizome while leaving it in the ground so you don't disturb the roots.....make sure any water the plant gets can drain away......and generously cover everything with a cleanser that contains bleach. And repeat the cleanser every time it gets wet or washed away.

I just had that happen with a new west coast iris I planted in August. While the original fan is history, I have four new increases that just began coming up around the original rhizome. Won't have bloom next year, but I saved it.

Neil

Never thought of using 'comet' or it's equivalent to sanitize the soil. It is
recommended for iris cuts/breaks/scrapes by every expert I have read.
Probably the last thing you would want to do would be pour more water
onto saturated soil.

Who said an old dog can't learn new tricks?

comet is great! Use it all the time.

D

I tried the Comet and it did not work as well for me as bleach, as far as leaving the iris alone and just digging the rot out, some of mine I have done that with and had great success, it just depends on how much rot you have. But just wondering, you can shake the comet right on the rhizome while it is in the ground and it will not hurt anything else?

From William Shear 'The Gardener's Iris Book': "..........the bleach is fatal
to bacteria, and the cleanser produces a strong alkaline environment in which
any surviving bacteria can't grow. There is no evidence that it hurts the irises.
An alternative that also seems to work is agricultural sulfur dust." He is
referring to scraping off the rotted matter down to solid white, crisp tissue.
The powder helps seal the wound. It is logical to assume the cleanser could
be sprinkled on top of the soil to help sterilize it.

Yes, thank you... I know how to treat the wound. I just wanted to know what the pest was so that I could prevent further infestation.

a grower in VA said you can squeeze a ring of antibacterial liquid hand soap around any iris having a problem like this, too. have no clue if it works, but I'm going to try it on a few myself this week.

OK-so I got an iris from a co-op that has some really smelly rot on the top of the main rz-so B4 I plant it, soak it inn the same bleach solution I do when I send them and let it scab over??

And Dee-what do you do with the comet??

scrub it with comet and a toothbrush, Stacey, to sterilize it even more. gets in there and kills most anything - like solid bleach.

AHHH-OK-thanks!!

OK-so I soaked it for like an hour in bleach solution, took a toothbrush to it to get all the stinky icky part out, but now off the main rz, like 1/4 of it is gone-rotted out-but there are 2 small ones coming off the sides-do I still have hope for the other 2 new ones??

I am sorry-don't mean to hijack this thread at all-I am just upset as it was NOT an inexpensive one:(

The 2 on the side are next yr's plants. Do keep an eye on the old part so they won't be infected.

So what do I do-plant it and pray it stops?? I don't think I can take the 2 little ones off yet can I?? Can I dmail you a pic when I get home today for more info??

There should be some parts of the 'mother rhizome' attached to the smaller ones, but will wait for the picture. DH can look at it, he is better at figuring out that type of problem than I am.

I just got home a little bit ago-I have to take a shower, eat dinner and go to bed so I can be up @ 4am for work-I will do it tomorrow-thank you so much!! I did feel it tonight-nothing mushy, but it still smells icky:(

has anyone mentioned not planting them into the exact same soil? it's likely contaminated.

They were from a co-op-not from my soil....

Not from Dee's either-just an FYI

OK-so I went to take a pic and while all the squishy parts are all gone-it still smells to all get out!! And the 2 little new ones are like empty if that makes any sense-usually they are firm, but these are like hollow....I am thinking it is a loss:( I will post a pic tonight...

I agree it looks like you lost that plant. I would let the source know, the person may not have realized that the plant was diseased.

I will let the host of the co-op know and she can see waht the company can do-heck I will send it back to them if they want-you woulda thought that soaking it in bleach for an hour would've taken care of the smell-but nope:(