Deuteronomy 20:19-20
19“If you besiege a city for many days, to make war against it in order to capture it, you shall not destroy its trees by swinging an axe against them; for you may eat from them, and you shall not cut them down. 1For is the tree of the field a man, that it should 2be besieged by you? 20“Only the trees which you know are not trees for food you shall destroy and cut down, that you may build siegeworks against the city that is making war with you until it falls.