Tu BiSvát

[With regard to] the prohibition of orlah, [planting a tree refers to] planting a seed, a bough from a tree, or uprooting the entire tree from one place and planting it in another. We begin counting [the three years] from the time of the planting.
[The following laws apply if] a tree was shaken from its place, but not uprooted and then one filled the surrounding area with earth. If it could live without the surroundings having been filled with earth, it is exempt. If not, it is considered as if it was uprooted and replanted, and the prohibition does apply.

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