My children are constantly getting a rash that looks like poison ivy they must have either a strong resistance or light exposure because it has yet to spread out of control . I know what poison oak , ivy and sumac rashes look like but the plants are a little tricky your info and pix have been very helpful but I haven't found a good picture of the sumac . I have a plant throughout my landscape that looks alot like the sumac you have described the pictures are attatched. I cannot find poison ivy or oak on the property but i have this stuff is this what is giving my kids the little breakouts??? P.S. I thought i had poison ivy but your pix and info tell me it is blackrasberry , and virginia creeper thanx!!!!