Winterberry and Bittersweet: Part 1

Which one is winterberry?

Winterberry (Ilex verticillata) and Asian bittersweet (Celastrus orbiculatus) grow throughout Minute Man National Historical Park. Both retain their bright red fruits in winter, providing a food source for birds and other wildlife. However, winterberry is a native shrub that grows near wetlands, while bittersweet is an invasive vine that often wraps itself around other plants. Bittersweet also has a distinctive yellow sheath enclosing each red fruit, which dries and splits open when ripe.

Stay tuned for part 2 of this article which explains the invasive nature of bittersweet and why birds prefer winterberry. Are you interested in helping us remove bittersweet and other invasive plants? Contact Kiah Walker at

Answer: Winterberry is on the left and bittersweet is on the right.

Written by Kiah Walker, Biologist at Minute Man National Historical Park.