What is "hop tree"

Hop \Hop\, n. [OE. hoppe; akin to D. hop, hoppe, OHG. hopfo, G. hopfen; cf. LL. hupa, W. hopez, Armor. houpez, and Icel. humall, SW. & Dan. humle.]

1. (Bot.) A climbing plant ( Humulus Lupulus), having a long, twining, annual stalk. It is cultivated for its fruit (hops).

2. The catkin or strobilaceous fruit of the hop, much used in brewing to give a bitter taste.

3. The fruit of the dog-rose. See Hip.

   Hop back. (Brewing) See under 1st Back.

   Hop clover (Bot.), a species of yellow clover having heads like hops in miniature ( Trifolium agrarium, and Trifolium procumbens).

   Hop flea (Zo["o]l.), a small flea beetle ( Haltica concinna), very injurious to hops.

   Hop fly (Zo["o]l.), an aphid ( Phorodon humuli), very injurious to hop vines.

   Hop froth fly (Zo["o]l.), an hemipterous insect ( Aphrophora interrupta), allied to the cockoo spits. It often does great damage to hop vines.

   Hop hornbeam (Bot.), an American tree of the genus Ostrya ( Ostrya Virginica) the American ironwood; also, a European species ( Ostrya vulgaris).

   Hop moth (Zo["o]l.), a moth ( Hypena humuli), which in the larval state is very injurious to hop vines.

   Hop picker, one who picks hops.

   Hop pole, a pole used to support hop vines.

   Hop tree (Bot.), a small American tree ( Ptelia trifoliata), having broad, flattened fruit in large clusters, sometimes used as a substitute for hops.

   Hop vine (Bot.), the climbing vine or stalk of the hop.