The Rubus genus of blackberries is so enormous and complex — there are nearly 30 species found in New England alone and they love to hybridize — that telling them apart is a specialized chore. Most gardeners are content to look for the telltale prickles, mumble “bramble” under their breath, and just be glad it’s not poison ivy as they pull it out.
The canes seen growing along Old Kings Highway in Truro, though, stand out. Rubus lacianata, the cutleaf blackberry, is an introduced Eurasian species identifiable by its deeply cut evergreen foliage; native species have fuller deciduous leaves. R. lacianata is considered noxious in the Pacific Northwest but has — so far — been documented only sporadically in Massachusetts.
