Forage for elderberries in late summer/early Autumn. Just make sure you're 100% certain that's what you've got! https://www.thegrizzlyforager.co.uk/elderberry/ The stalks of elderberries are toxic, so please remove and discard them. It's a tedious job but having done it a few times now, the resulting syrup is so good that I'm more than happy to do this multiple times over the summer. A little tip is to freeze them first so the berries pop off easier.