Deuteronomy 20:18-22

so that they will not teach you to do all the same detestable practices of theirs which they have done for their gods, by which you would sin against the Lord your God.

“When you besiege a city for a long time, 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, so you shall not cut them down. For is the tree of the field a human, that it should be besieged by you?

Only the trees that you know are not fruit trees you shall destroy and cut down, so that you may construct siegeworks against the city that is making war against you until it falls.