Yerushalmi Bava Batra 5:2 ירושלמי בבא בתרא ה׳:ב׳

MISHNAH: He who buys two trees on another’s property did not acquire the land⁵⁶On which the trees stand.; Rebbi Meїr says, he acquired the land. If they grew, he need not cut them⁵⁷Anything that grows from the tree, neither new shoots nor expanding crowns which extend beyond the range they had at the time of sale.. What grows from the stem is his, from the roots⁵⁸A new tree coming out of the earth. is the owner’s of the ground. If they died, he has no land⁵⁹Cf. Chapter 4, Note 79..
If he bought three, he bought the land. If they grew, he has to cut them⁶⁰Anything which will grow into the original owner’s land is no different from trees growing in one orchard and overhanging another owner’s property (Halakhah 2:14).. What grows from the roots is his. If they died, he has the land.

HALAKHAH: “He who buys two trees on another’s property,” etc. (The words)⁶¹Reading of L. [In the House of]⁶²Reading of E. Rebbi Yannai they said, what sees the shadow is root, what sees the sun is stem⁶³Babli 82a, in the name of R. Joḥanan. The question is, what is meant by “growth from the roots”? The entire tree grows from the roots. On the other hand, unless lifted by man, most roots will feed just one stem. Where does one draw the line between stem and roots at the bottom of the stem?. Rebbi Ḥama bar Uqba in the name of Rebbi Yose: What grows from its roots and its stem is root, from its stem but not its roots is tree⁶⁴Anything grown as a branch is the buyer’s; anything else is the landlord’s.. Rebbi Joḥanan said⁶⁵Babli 82a. It is understood that this only applies to trees which qualify for an orchard; i. e. that the distance between two trees be no larger than √250 = 15.81 cubits (cf. Ševi‘it 1:2, Note 18)., he who buys three trees buys the land in between them, under them, and outside of them the width of the harvester and his bag⁶⁶Four cubits around each tree (Chapter 2, Note 101; Ševi‘it 1:2 Note 19). Rebbi Eleazar said, while he has no access⁶⁷Unless the trees are directly accessible from the road, buying the trees does not buy access. (But the person who only buys two trees rents the land and has free access as a renter; Babli 82b.), he has the width of the harvester and his bag outside of them.