Commentaire sur Péa 1:5

האוג – [the red berry of the Venus’ summachtree] – a tree whose fruit is red which is called in a foreign language KURNI ULIM. And Maimonides explained that it is a plant that dresses hides and is called in Arabic SIMMAC, and its clusters are appropriate for eating, but not specifically these which the Tanna [of our Mishnah] enumerated are liable for [the Mitzvah of] PEAH/the corner of the field and not other kinds of trees other than these, rather these and anything similar to them are mentioned.

Among trees: the sumac, the carob, the nut, the almond, the grapevine, the pomegranate, the olive and the palm are subject to peah.
This mishnah teaches which trees are subject to the laws of peah. The fruit of all of these trees is harvested in one harvest and is not harvested more gradually over a longer period of time. Other trees such as figs are exempt from peah.