Clematis terniflora’s common name, sweet autumn clematis, does a lot of PR work for this badly behaved garden vine, which is repeatedly guilty of reseeding itself into neglected spaces and other people’s flower beds. A mass of this vigorous non-native is pictured here growing by the remains of the Old Reliable Fish House in Provincetown, where it joins Japanese knotweed and tree-of-heaven in a glut of invasive vegetation. The Native Plant Trust — the region’s authority on natives and invasives — has dubbed it “yam-leaved virgin’s-bower” instead, a less romantic name for a more-and-more troublesome plant. Whatever one calls it, the gorgeous, picturesque mounds that are blanketing Provincetown’s fences and hedge rows this week are a selling point that’s hard to spin.
