Mollison has said: Permaculture is a philosophy of working with, rather than against nature; of protracted and thoughtful observation rather than protracted and thoughtless labour; and of looking at plants and animals in all their functions, rather than treating any area as a single product system..
The juice of jewelweed is a traditional remedy for all sorts of skin ailments including poison ivy. An oft-repeated folk saying, Wherever poison ivy is found, jewelweed grows close by. To use it, you can simply crush the leaves and rub it on the itchy places.
If this is too much work, get a weed killer that works on poison ivy, and use a small pump sprayer to spray it directly on the plants, while avoiding getting spray on other plants as best you can.This is generally the best option depending on the size of the job. Follow the directions for use of the weed killer EXACTLY.