If it is uncertain whether certain fruits are orlah [from the first three years since a Jew planted the tree; perhaps the tree is older or was planted by a non-Jew]: if it is in the Land of Israel, it is forbidden; if in Syria, it is permitted; and if completely outside the Land, then he can go down to the orchard and buy the fruit so long as he isn’t seen picking it. A vineyard which has vegetables mixed in it, and outside it vegetables are being sold [possibly from the vineyard and thus forbidden as kilayim, a banned admixture]: if it is in the Land of Israel, it is forbidden; if in Syria, it is permitted; and if completely outside the Land, then he can go down to the orchard and gather the fruit so long as he isn’t seen picking it himself. New grain [chadash, e.g., winter wheat before the omer is offered on the second day of Pesach] is forbidden by the Torah in all places. Orlah law is traditional, and vegetables mixed in a vineyard are forbidden by the rabbis [within Israel].
This Mishnah refers to three agricultural rules of Israel: fruit from trees is forbidden in the first three years after the tree is planted, different species cannot be grown together, and new grain (chadash) is forbidden until after the omer offering on Pesach [after which it is called "old" (yashan)]. Our Mishnah considers two cases in which there is doubt whether these restrictions apply. In such cases, the law is strictest within Israel, more lenient in the bordering territory of Syria, and most lenient abroad. Even there, however, a Jew should not be seen flaunting the rules.
One line of our Mishnah had a famous afterlife. The great Hungarian rabbi Moses Sofer of Pressburg quoted "the new [grain] is forbidden by the Torah in all places" as a slogan to attack innovations in Judaism being proposed by the maskilim.