While the most common plants that cause allergic dermatitis are the Poison Ivy, Oaks, and Sumacs there are many others that can also, and often what did cause that allergic dermatitis may not be something well known. if you can for sure eliminate Poison Ivy, Poison Oak, or Poison Sumac then you need to look for others. To reduce the chance for allergic dermatitis wash well after gardening with strong soaps such as Fels Naptha.

Here is a link that might be useful: Causes of allergic dermatitis

Mugwort, nettle, rue, tansy, regular ivy are regular offenders in the dermatitis category. You could be allergic to a specific plant that isn't one of the usuals, as well. What have you got growing where you were working? What trres or bushes could have dropped some pollen on you? Any medication you are on could be reacting weirdly with something too.
I hope you get it figured out, so you don't have to dig up your plants!

I don't have any Euphorbia in my garden. I looked at the images that you posted, and I don't see any of those in my flower beds.

No trees in my flower bed. Not on any meds. I did have a few vining plants that I pulled out but they weren't leaves of three.

How do I post pictures?

Thanks for all your help and suggestions!!

"How do I post pictures...?" At the top of this page there's a blue highlighted text 'How to upload images'.

Alanis, one persons reaction to contact with a plant can be so different to someone elses, it's hard to say what caused your discomfort. There are specific plants that may cause a dermatitis in some, but yours could be something no one else might experience.

You might try going inside and washing arms, face, hands with lots of warm soapy water when you've finished weeding and before you notice symptoms if that's possible. Maybe change your shirt too and put it in the laundry. I was encountering something picking wild berries one year that I never did identify (the offending native, not the berries :)) and a wipe with an alcohol pad from the first aid kit once back in the truck helped stop the itching and irritation.

I'm fine with the euphorbias, monkshood, many of those commonly causing problems for others but I will never, ever open hellebore seed pods to extract the seeds with bare fingers again - that was painful for days....

But if you could post photos or at least tell us what is in that bed where you've found you have problems, we might be able to tell you the most likely candidate that you could then remove.

I may not be much help, having never been to IA or gardened in Z4, but I've done some fairly extensive investigation in this area also, the past few years, trying to figure out what was giving me a rash. Happy to try to help also!

Some of the ones I think you might have up there... Ipomoeas and Asclepias (milkweed) can have latex sap. (Morning glory, bindweed. White, milky sap can indicate the presence of latex, but not always, and clear sap can have latex.) Virginia creeper and wild grape vines are often blamed for contact dermatitis. Sonchus (one of the dandelions also has latex sap.)

If you have any house/potted plants that you were also pruning or taking cuttings, those are worth mentioning also. May suspects among that crowd as well.

Here's an idea to tell you which plant reacted to your skin....I realize it was a painful rash, but you could go back into the garden and expose your skin to each plant to different areas of your arms or legs......similar to what a dermatologist would do......that way you will know what plant to avoid or get rid of.......just a thought......

Depending on the severity and frequency of this reaction Alanis may want to consider consulting an Allergist rather then a Dermatologist.

Rue (ruta graveolens) and giant hogweed (hieracleum mantegazanni) are 2 plants which immediately come to mind, especially after exposure to sunlight It would surely be helpful to have some images to identify which plants are possible culprits, to save you from being further afflicted.

The discussion I started about this in the Alabama forum has become general enough to be helpful in any location. And so is my apparent new sensitivity to several types of plants. My long-time friend, heart-leaf Philodendron now gives me a rash, as well as long-time decorative accent, sweet potato vine.

Anyway, there are a whole lot of plants out there that can give *some* people a rash, sometimes...! So strange!

Here is a link that might be useful: rash discussion

Alanis, did you ever figure out why you got a rash?