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Elevation of Pine Rocklands

Pine rocklands -- also called rock pinelands, rimrock pines or, in the Bahamas, pineyards -- are some of the most biologically diverse communities in South Florida and the Caribbean. Spatially similar to the extensive pine flatwoods that cover much of the Atlantic-Gulf Coastal Plain in the Southeast, these subtropical woodlands differ in overlying rugged, pockmarked benches of limestone instead of loose sands and clays. Made rare by logging and especially development, pine rocklands are notably protected in Everglades National Park, Big Cypress National Preserve and refuges on the Florida Keys.

Modern Distribution
- Pine rocklands once covered large swaths of far southern Florida and the Bahamas, but are now much reduced in acreage. One of the most significant communities grows on the Miami Rock Ridge, a 70-mile belt of limestone running from the North Miami Beach area southward and westward into the eastern region of Everglades National Park in the form of Long Pine Key. Outside of the park, only about 2 percent of the Miami Rock Ridge's pine rocklands remain. Other notable remnants are found among the swamps and savannas of the Big Cypress and on the Florida Keys. Very similar pineland communities occur on the northern islands of the Bahamas, with the slash pine of the Florida mainland replaced by Caribbean pine.
Elevation
- Florida is a relatively subdued landscape representing the above-water portion of a broad limestone bench, the Florida Platform, that partly divides the Atlantic Ocean and the Gulf of Mexico. Topographic relief is extremely minimal in South Florida, but the difference of a few feet of elevation -- common because of the easily weathered nature of the limestone bedrock -- has great ecological influence. The pine rocklands of the Miami Rock Ridge, which ranges in elevation from around 20 feet in the vicinity of Miami to under 2 feet in the Everglades, prosper on the scanty soils of exposed limestone, while slightly lower elevations adjacent support sawgrass marshes and cypress swamps. Pine ecosystems of the Florida Keys range from 3 to 6 feet above sea level.
Ecology
- Saw palmetto is a significant understory shrub in pine rocklands.
  
  The spindly, tough-wooded slash pine forms pure, airy canopies in the Florida rocklands. These diverse ecosystems harbor hundreds of kinds of plants, some, like pineland spurge, found nowhere else in the world. The heraldic understory species are stunted palms, including saw palmetto, cabbage palm, Florida thatch palm and silver palm. Wildlife ranges from northern mockingbirds and eastern diamondback rattlesnakes to Florida panthers and Key deer.
Fire Regime
- South Florida has the highest rate of thunderstorms in the mainland United States, and thus experiences a lot of lightning. Lighting causes wildfires every few years, which help maintain the pine rocklands. Such blazes remove tropical hardwoods that otherwise would invade and eventually shade out slash pines. Hardwood hammocks -- islands of broadleaved trees -- are scattered in the pine rocklands, maturing where fire has been absent for long periods.

Nature