Devarim 20:19

ימים [WHEN THOU SHALT BESIEGE A CITY] ימים DAYS — The plural implies at least two days, רבים MANY must imply at least three days (cf. Rashi on Leviticus 15:25). From here they (the Rabbis) derived the law that the siege of a heathen city must not be commenced less than three days before the Sabbath, and it (this verse) teaches you that the opening up (the invitation to make) peace (v. 10) must be repeated two or three days, for so it states, (II Samuel 1:1) “And David abode two days (ימים שנים) in Ziklag” (Sifrei Devarim 200:4; Shabbat 19a). And Scripture is speaking here of a war which is not obligatory upon them (Sifrei Devarim 200:1). כי האדם עץ השדה FOR IS THE TREE OF THE FIELD A MAN [THAT IT SHOULD BE BESIEGED BY THEE]? — כי has here the meaning of “possibly”, “perhaps” (cf. Rashi on Exodus 23:5) — is the tree of the field perhaps a man who is able to withdraw within the besieged city from before you, that it should be chastised by the suffering of famine and thirst like the inhabitants of the city? Why should you destroy it?

כִּֽי־תָצ֣וּר אֶל־עִיר֩ יָמִ֨ים רַבִּ֜ים לְֽהִלָּחֵ֧ם עָלֶ֣יהָ לְתׇפְשָׂ֗הּ לֹֽא־תַשְׁחִ֤ית אֶת־עֵצָהּ֙ לִנְדֹּ֤חַ עָלָיו֙ גַּרְזֶ֔ן כִּ֚י מִמֶּ֣נּוּ תֹאכֵ֔ל וְאֹת֖וֹ לֹ֣א תִכְרֹ֑ת כִּ֤י הָֽאָדָם֙ עֵ֣ץ הַשָּׂדֶ֔ה לָבֹ֥א מִפָּנֶ֖יךָ בַּמָּצֽוֹר׃

When thou shalt besiege a city a long time, in making war against it to take it, thou shalt not destroy its trees by forcing an axe against them: for thou mayst eat of them, and thou shalt not cut them down; for is the tree of the field a man, that it should be besieged by thee?