Talmud - Bava Metzia 119a בבא מציעא קי״ט א׳

And we also learned a case like this in a baraita (Tosefta, Orla 1:4), with regard to the prohibition against eating the fruit of a tree during the first three years after its planting [orla]: In the case of a tree that sprouts from the trunk and from the roots of an old tree, its owner is obligated in orla, since it is considered like a new tree, and the orla years must be counted anew. This is the statement of Rabbi Meir. Rabbi Yehuda says: If it sprouts from the trunk, the owner is exempt, since it is considered like a branch of the old tree, but if it grows from the roots, the owner is obligated.

The Gemara comments: And both cases are necessary to be stated although they are both based on the same principle. As had it taught us only the first halakha, that of ownership, one could say that it is only with regard to this case that Rabbi Yehuda said his ruling, due to the fact that it pertains to monetary matters, but with regard to orla, which is a matter of a prohibition, one could say that he concedes to Rabbi Meir. And if it was stated only with regard to this case of orla, one could say that it is only with regard to this case that Rabbi Meir said his stringent ruling, but with regard to that case, one could say that he concedes to Rabbi Yehuda. It is therefore necessary to state both disputes.

§ The mishna teaches: Rabbi Shimon said: Any vegetables that the owner of the upper garden can stretch out his hand and take, those vegetables are his, and the rest belong to the owner of the lower garden. In the school of Rabbi Yannai they say: And this is only so provided that he does not force himself, but simply stretches out his hand in the usual manner.

Rav Anan, and some say it was Rabbi Yirmeya, raised a dilemma: If the owner of the upper garden can reach its leaves, but he cannot reach its roots, or if he can reach its roots but he cannot reach its leaves, what is the halakha? Is the plant considered to be within his reach or not? No answer was found for this question, and the Gemara concludes: The dilemma shall stand unresolved.

Efrayim the scribe, a student of Reish Lakish, says in the name of Reish Lakish: The halakha is in accordance with the opinion of Rabbi Shimon. They stated this case before the Persian King Shapur, who expressed an interest in this legal issue, and he said to them: Let us offer praise [apiryon] to Rabbi Shimon. He too felt that this was the best resolution.

Traduction : The William Davidson digital edition of the Koren Noé Talmud, with commentary by Rabbi Adin Even-Israel Steinsaltz.

Bava Metzia 119a explores orla laws for regrowth from tree trunks or roots, plus a dispute over reachable garden vegetables between adjacent landowners.