Menispermum canadense is a woody vine, climbing on adjacent plants or running along the ground if nothing is available to climb on. The leaves are simple, alternate and usually shallowly lobed. Fruits are blue drupes 6-10 mm diameter with a single large flattened seed suggesting a crescent moon (and thereby providing the common name).

The fruits of Menispermum canadense are reported to be poisonous with potentially fatal consequences. The fruits are roughly similar to those of our Vitis riparia (frost grape) and wild food foragers should be very careful to distinguish between the two, and to refrain from eating wild fruits if they are not absolutely sure of the identification.

Vitis riparia has 2-6 blunt, ovate seeds per fruit and the fruits of Menispermum canadense each contain a single flattened crescent-shaped seed. Compare seeds of the two species.

Vitis riparia also usually has tendrils and Menispermum canadense does not.