(baʹca) [Heb., ba·khaʼʹ].
The plant that played an important role in David’s encounter with the Philistines “in the low plain of Rephaim.” (2Sa 5:22-25; 1Ch 14:13-16) The only other reference to the plant is at Psalm 84:6: “Passing along through the low plain of the baca bushes, they turn it into a spring itself.” This may refer to the same “low plain of Rephaim” where David’s fight took place and which plain is believed to be SW of Jerusalem.
The Hebrew word used comes from a root meaning “weep.” (Compare Ge 21:16.) It therefore seems to indicate a plant, shrub, or tree that exudes tears of gum or perhaps a milky sap. Its identification is uncertain; the name baca is simply a transliteration of the Hebrew word. There is no apparent foundation for the rabbinic view that relates it to the mulberry tree (as also translated in KJ). Since balsam trees (of which there are several in the different tree families) exude gum or resin, these have been suggested by many scholars. A balsam tree of the poplar family (Populus euphratica) is recommended by some botanists, primarily because of the ease with which its leaves are stirred by any breeze, producing a rustling sound. However, the Bible does not specify how “the sound of a marching” was produced (whether by means of the leaves, the branches, or some other part of the plant) and simply indicates that it occurred in “the tops” of the plants. It could have been a mere rustling sound that served as a signal, or as suggested by some, it may have been a noise of some volume produced by a rushing wind that served to cover up or even to simulate the sound of a marching army.—2Sa 5:24; 1Ch 14:15.