Hello, I have 2 Bittersweet vines, an unknown 5 year old male and a 2 year old female "CELASTRUS orbiculatus Diana". The leaves are SO hard to tell apart. On the male - one branch will have both pointed and completely round leaves, changing from one to the other along the branch - and on some male branches not a pointed leaf to be seen. On the female, there are no pointed leaves at all. I ventured inside the mass of tangles and did a major pruning job but boy was it difficult to tell the two apart. I had to try and follow the vines - the berries were a giveaway for the girl. Are there any other ways to pick them apart? Do they both have little claw-like hooks? It didn't give up without a fight! Many thanks. PS. I've recently read that it's a terribly invasive vine - however in the 4 years since the male was planted, I've seen only one sprout. Am I just lucky or does it need a few years to take over the neighbourhood?