Rabban Shimon ben Gamliel says: The shoots of fenugreek, of mustard, and of white beans are obligated in tithes. R' Eliezer says: The caper bush requires tithing [of its] shoots, berries, and husks. R' Akiva says: It does not require tithing [of anything] other than its berries, because they are “fruit” [of the bush].