Is this hollyhock or poison oak or?
Hi. That is a shrub known as rose-of-sharon, which is in the same family as hollyhock (and hibiscus). As you have undoubtedly discovered, it is an aggressive seeder. The U. of Connecticut and Ohio State have fact sheets on rose-of-sharon here and here if you would like more information about the plant. For information about poison oak and other related plants, I’d suggest you check out this fact sheet from the U. of Florida.