The fruitful land, the Lebanon range, the plain of Sharon, and the regions of Bashan and Carmel are used by Isaiah to describe what happens in Israel due to the Assyrian invasion.
Behold, their heroes cry in the streets; the envoys of peace weep bitterly. The highways lie waste; the traveler ceases. Covenants are broken; cities are despised; there is no regard for man. The land mourns and languishes; Lebanon is confounded and withers away; Sharon is like a desert, and Bashan and Carmel shake off their leaves. (Isaiah 33:7-9 ESV; see similar language in 2:13)
Homer Hailey comments on this text,
The language is figurative, suggesting that the land reflects the spirit of the people whom the invaders are overrunning and devastating. Four ordinarily flourishing sections of the country are described: Lebanon, the mountain range to the north, noted for its majestic beauty and mighty cedar and fir trees, is confounded and withereth away; Sharon, the verdant and flower-rich plain extending south from Carmel until it melts into the Shephelah of western Judea, is like a desert; and Bashan, extending northwest from the Sea of Galilee, noted for its oak groves and rich grazing land, and Carmel, the verdant mountains or hill that juts into the Mediterranean Sea, shake off their leaves, so that the trees are bare. The picture is one of dejection, of both people and land (A Commentary on Isaiah With Emphasis on the Messianic Hope, 280).
When the redeemed return to Zion these once glorious and verdant regions shall once again be majestic.
The wilderness and the dry land shall be glad; the desert shall rejoice and blossom like the crocus; it shall blossom abundantly and rejoice with joy and singing. The glory of Lebanon shall be given to it, the majesty of Carmel and Sharon. They shall see the glory of the LORD, the majesty of our God. (Isaiah 35:1-2 ESV)
For our most recent comments on the Cedars of Lebanon, see here.