As I wrote in 'Marsh Mud and Mummichogs', the best-loved coastal tree is the live oak, Quercus virginiana. The low spreading branches, draped with Spanish moss, are an iconic hallmark of the South. (Photo above shows live oaks on the south end of Sapelo Island)
Live oaks are home to other plants, termed epiphytes because they live on the surface (epi-) of the oak branches. The most visible of the epiphytes is Spanish moss, Tillandsia usneoides. This is actually not a moss, but is instead a bromeliad, a flowering plant that is, amazingly, related to pineapples. The tangled mass of stems bearing miniscule scaled leaves hangs down from the trees like a gray beard and provides shelter to insects, spiders, snakes, and even bats.
Close-up of the scaly gray stems of Spanish moss with a tiny reddish flower. "Sp moss flower 1545" by Original uploader was Pollinator at en.wikipedia - Transferred from en.wikipedia. Licensed under CC BY-SA 3.0 via Wikimedia Commons
A species of jumping spider, Pelegrina tillandsiae, which has a body camouflaged to mimic the color of the Tillandsia stems, is endemic in Spanish moss. Warblers are fond of raising their young in the big oak trees, using Spanish moss to line their nests. The oaks host a variety of other plants. Pink crusty lichens grow on the thick, corrugated bark. The huge drooping limbs of the trees bear a garden of resurrection ferns and vines. Once I was shown a rather large prickly pear cactus growing in the crotch of an old oak. In addition to the resident squirrels, island deer fatten up for the winter on the abundant crop of acorns produced by live oaks each fall.
Unlike oaks that lose their leaves in autumn, live oaks keep green leaves year-round. But that doesn't mean the leaves don't drop, as I found out each April when we had to sweep the porch of our house on Sapelo every day to keep up with falling oak leaves. Each leaf stays on the tree for only about two years. During spring, live oaks shed half their leaves, the ones that are two years old, and grow tender new leaves to replace them.
During the age of sailing ships, live oaks on Georgia sea islands supported a thriving timber business: the export of naturally curved, tough hardwood to shipbuilders in the Northeast. Wood from live oaks on St. Simons Island was used for internal framing and planking in the first American naval frigates. The most famous of these is the USS Constitution, constructed in 1797. The Georgia live oak wood in the hull was so tough, and so impervious to British cannon fire in the War of 1812, that the ship was given the famous nickname "Old Ironsides." The USS Constitution survived the war, and has been preserved as a historical museum at the Charlestown Navy Yard in Charlestown, Massachusetts.
Wood used to build the tough hull of the historic US naval ship 'Old Ironsides' came from live oak trees felled and milled on St. Simons Island.
"USS Constitution fires a 17-gun salute" by (U.S. Navy photo by Seaman Matthew R. Fairchild/Released) 140704-N-OG138-866 - https://www.flickr.com/photos/usnavy/14595957594/. Licensed under Public Domain via Wikimedia Commons
After we moved to Oregon, we found trees in the Willamette Valley festooned with long gray drapes of what appeared to be Spanish moss. On closer inspection, the Oregon 'moss' was in fact hanging lichens, one species of which, called Methuselah's beard, is eerily similar to Spanish moss. Whenever we see these lichens falling in long curtains from the branches of local trees, we remember the mossy oaks on the Georgia coast.
Lichens hanging from trees in the Willamette Valley remind our family of the Spanish moss draping the live oaks on Sapelo Island. These trees were in a swamp in the Findlay National Wildlife Refuge near Corvallis, Oregon.