Matthias Wandel on youtube has a video of a DIY woodworking project for building a wild parsnip harvester that doesn't require touching the plant, for the purposes of manually eradicating it.
Neat! I never knew about poison parsnip until a few years ago when I developed a burn on my arm a few days after flyfishing on a small stream on the 4th of July. It was pretty small all things considered, but very painful and took weeks to heal.
I have not seen that video, but he puts a lot of engineering work into his projects and might be hard to replicate if you are a DIY'er. Great videos to watch.