Virginia Tech Weed Identification Guide

Japanese Hops: Humulus japonicus

Weed Description:  Annual climbing or trailing vine with  5-lobed leaves and stems with prickles.   Japanese Hops is primarily a weed of pastures, hayfields, and other noncrop areas that is found throughout Virginia, Tennessee, North Carolina, and West Virginia.
Leaves:  Leaves are approximately 2 to 4 inches long and are divided into 5 distinct lobes.  Leaves are rough to the touch and occur on petioles that may reach 8 inches in length.  Bracts occur at the base of the leaf petioles.

Stems: Climbing or trailing along the ground and are covered with small prickles that are turned downward.  Bracts occur where the leaf petioles attach to the stem.

Flowers:  Individual flowers are relatively inconspicuous, without petals, and green in color.  Flowers occur in clusters that may reach 2 1/2 inches in length.

Fruit:   An achene.

Identifying Characteristics:   The climbing or trailing growth habit, conspicuously 5-lobed leaves, and stems with downward pointed prickles are all characteristics that help in the identification of Japanese hops.  Wild cucumber (Echinocystis lobata) also has 5-lobed leaves and a similar growth habit, however this weed has tendrils and does not have the downward pointing prickles along the stem like Japanese hops.