Deuteronomy 20:19-20

19“When you besiege a city for a long time, while making war against it to take it, you shall not destroy its trees by wielding an ax against them; if you can eat of them, do not cut them down to use in the siege, for the tree of the field is man’s food.

20Only the trees which you know are not trees for food you may destroy and cut down, to build siegeworks against the city that makes war with you, until it is subdued.