Orlah ערלה

For three years the fruit of a young tree is entirely forbidden: it is neither eaten nor sold. In the fourth year the fruit is holy and is brought up to Jerusalem like the second tithe, and only from the fifth does the tree belong to its owner without reservation.

The tractate deals with counting the years—from what day the planting is reckoned—and with mixtures: what to do if forbidden fruit has fallen among permitted. Orlah is one of the few commandments of the land which, in the sages' view, applies outside the Land of Israel as well.

Order: Zeraim. There is Gemara only in the Jerusalem Talmud.