This section is from the book "The Gardener's Monthly And Horticulturist V24", by Thomas Meehan. See also: Four-Season Harvest: Organic Vegetables from Your Home Garden All Year Long.
The Philadelphia Public Ledger says :
Two persons own land separated by a line fence, which is common property between the two parties. One has an apple tree on his side of the fence, whose limbs overhang the fence on the side of the other. Apples fall on either side. The question often asked is, Do the apples that fall on one's land belong to one or the other, or to both ? This subject has been several times discussed, with some contradictory decisions and judgments, but the rules are now pretty well established. If the stem or trunk of the tree grows so close to the line that parts of its actual body extend into each, neither owner can cut it down without the consent of the other, and the fruit is to be equitably divided. If the stem of the tree stands wholly within the boundary line of one owner he owns the whole tree with its products, although the roots and branches extend into the property of the other. There was an old rule of law that the latter might claim from the yield of the tree as much as would be an offset for the nourishment it derived from his estate, but this is now obsolete. The law gives the land owner on whose soil the tree stands the right to cut it down at his pleasure, and to pluck all the fruit from it while it stands.
In New York State the courts have decided that trespass for assault and battery would lie by the owner of the tree against the owner of the land over which its branches extended if he prevented the owner of the tree, by personal violence, from reaching over and picking the fruit growing upon these branches while standing on the fence dividing the lands. The owner of the land over which the branches extend may lop the branches close to his line. He may also dig down and cut the roots square with his line, if he so elects. In plain terms, if no portion of the trunk is within his line he may refuse all trespass of the tree on his premises, either above the ground or below it. But if he gives the tree license either to extend its roots under his soil or to hang its branches over his premises he does not thereby gain any right to its fruit. He cannot pick it for himself nor interfere with the picking by the owner, as long as the latter remains in the tree or on the fence which divides the property. This right to the fruit does not, however, permit the other owner to come upon the soil on the other side of the line to gather the fruit, and all the fruit which falls without violence to the ground on that side may thus become the property of its owner.