The short work De Arboribus, "On Trees", was in early editions of Columella placed as book 3 of De Re Rustica. However it is clear from the opening sentences that it is part of a separate and probably earlier work. As the anonymous translator of the Millar edition notes (p 571), there is in De Arboribus no mention of the Publius Silvinus to whom the De re rustica is addressed. A recent critical edition of the Latin text of the De re rustica of Columella includes it, but as incerti auctoris, by an unknown hand. Cassiodorus mentions sixteen books of Columella, which has led to the suggestion that De Arboribus formed part of a work in four volumes.
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