'Mulberry trees' in the Bible

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.

And it shall be, when thou hearest the sound of marching in the tops of the mulberry-trees, that then thou shalt bestir thyself; for then is Jehovah gone out before thee to smite the host of the Philistines.

And David inquired again of God; and God said unto him, Thou shalt not go up after them: turn away from them, and come upon them over against the mulberry-trees.

And it shall be, when thou hearest the sound of marching in the tops of the mulberry-trees, that then thou shalt go out to battle; for God is gone out before thee to smite the host of the Philistines.