What are the best ways to deal with poison hemlock. In the spring I noticed a huge patch of what turned out to be poison hemlock behind our shed. Very odd but I did find two very small plants that had flowers. I pulled it all up but of course more keeps coming up. Also, I keep finding seedlings in other parts of the yard, as well. I'm at Broadkill and am sure it must be in the marsh and neighboring properties as well.