John Gill Commentary Zechariah 11:2

"Wail, O fir-tree, for the cedar is fallen, because the goodly ones are destroyed: wail, O ye oaks of Bashan, for the strong forest is come down." — Zechariah 11:2 (ASV)

Howl, fir tree; for the cedar is fallen
By which are designed the princes, nobles, and magistrates of the land: so the Targum interprets them of kings and princes; see (Nahum 2:3) (Ezekiel 31:3) : because all the mighty are spoiled ;
which is an explanation of the figurative expressions in the former clause, and in the following; and designs rich men, as the Targum paraphrases it, who at this time would be spoiled of their wealth and substance. Howl, O you oaks of Bashan ;
which the Targum interprets of governors of provinces; and men of power and authority are doubtless intended; see (Isaiah 2:13) (Amos 2:9) : for the forest of the vintage has come down ;
or rather, "the fortified forest"; meaning the city of Jerusalem, which was a fortified place, and like a forest full of trees, for number of inhabitants, but now cut down and destroyed; see (Isaiah 10:16–19) .