173:3 It makes no difference whether one plants a seed or a branch, or whether one uproots a tree and replants it in another place: the laws of orlah apply to them equally. However, if one grafts a branch onto another tree, or if he makes a furrow in the ground and bends the branch of a tree into the middle of the ground so that its end protrudes from the other side, even though it was detached from the trunk of the tree, this is not considered orlah outside of Israel.
173:4 If a tree was cut down but a handbreadth of height remains, then whatever grows later is not obligated in orlah; if less than a handbreadth remained, then it is obligated in orlah. For this, we count the years from when the tree was cut down. If a tree was uprooted but some of its roots remained in the ground – even as little as the width of a needle – if it is clear that it can stay alive without adding more soil, then it is exempt from orlah even if much soil was added.