Get some long sleeve grubbies to do the dastardly killing of poison ivy, and plan on just chucking them in the garbages especially since you had such a bad reaction to it before.
Don't forget hair cover and tape all possible openings of clothing
If you put down the carpet in the spring when its little, you shouldn't have to trim/cut the plants. You could go ahead and dose the ground with vinegar or concentrated ROUND UP before laying carpet.
If you have to cut the plants you might want to consider wearing a mask just in case. I'd rather be hot and uncomfortable than breathe it in.
Usually if you post to FC you can get all the carpet you want. Since it sends out runners (like the Japanese Knotweed I knew eventually I'd remember it's real name) start at least 5-8 ft from the outside edge and work in. Otherwise it sends out runners to the edges, this way it sends back to center and eventually it will die (evil laughter). Lay carpet at least 3 layers thick do not have any seams on top of each other or the darn runners will creep out.
Since you have clay, you might want to just leave down the carpet and put new soil, compost etc on top and build from there. Raised beds etc
WARNING POISON IVY:
Be aware that, even after you kill poison ivy plants, they remain toxic. So be careful in disposing of the roots of the dead vines after pulling back the smothering agent (even if you've waited for years).
IDEAS FROM ONLINE:
You can stick the ends of the vines in bottles of weed killer; neater than spray, easier than painting.
Use a paint roller to apply the poison ivy “killer”. It only goes where you want it, doesn’t spray onto the veggies and is quite effective.
Another thing I have done is to cut down the vines on a HOT day, MID-DAY when the sun is high and hot. Apply the weed killer directly to the newly cut stem and the plant will suck it right up! Use a systemic killer for this and it will go no further than the Poison Ivy.
HOW TO GET RID OF POISON IVY PLANTS
How to Get Rid of Poison Ivy Plants - wikiHow
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