Albert Barnes Commentary 2 Samuel 5:23

"And when David inquired of Jehovah, he said, Thou shalt not go up: make a circuit behind them, and come upon them over against the mulberry-trees." — 2 Samuel 5:23 (ASV)

The mulberry trees - Rather, this refers to the Baca tree, which is found abundantly near Mecca. It is very similar to the balsam tree and probably derives its name from the exudation of sap, which looks like teardrops when a leaf is torn off. Some believe the valley of Baca (Psalms 84:6) was so named because this plant grew there.