North of the Fall Line

Sandstone Outcrops

sandstone outcropsThe Arboretum’s Sandstone Outcrop Display has been built entirely from plant material donated by Moss Rock Preserve on Shades Mountain in Hoover Alabama. It includes many types of plants that typically grow in moist woodlands. Each of these plants has evolved into specialized species that can handle the exposed conditions common to all rock outcrops. You can find iris, ferns, phlox, violets, and spiderworts growing in the veins of the sandstone glades that form where water seeps out into the pioneer soils continually being developed by moss and lichens between the stone outcroppings.

These outcrops are also home to the Boynton Oak, a rare dwarf oak endemic (meaning native to a specific area and nowhere else) to this habitat type in this physiographic region of Alabama. That means that this species grows only around the exposed tops of the sandstone mountains that run in a southwestern slant roughly from Gadsden to Birmingham.

Ketona Glades and Limestone Outcrops

ketona glades and limestone outcropsThis habitat is home to one of the most amazing pockets of plant diversity known. In fact the specialists that persist here are on such a tiny piece of land that they grew undiscovered until the 1990’s when eight new species were discovered there. It was declared North America’s greatest botanical discovery of the twentieth century.

This habitat also shows how plant communities are dictated by the soils which result from weathering of the bedrock. In this case the Ketona dolomitic limestone resulted in extraordinarily high levels of magnesium which excluded many species leaving a niche where specialists could evolve to fill this very localized set of habitats including seeping glades, rock outcrops, creekbanks, and woodlands.

Our Ketona Glades Display is home to the Arborteum’s greatest concentration of rare plants, including multiple species that are federally listed as endangered species, threatened species, and even one believed to be extinct in the wild. We also have on display some of the newly described species endemic to the Ketona Glades, including the Alabama Gentian Pinkroot and the Ketona Tickseed.

Mountain Bogs

mountain bogMost of Alabama’s Pitcher plants are restricted to the Coastal Plain, but there is one species that is restricted to the extreme northeastern corner of the state. The Green Pitcher plant is listed as a Federally endangered species. The Arboretum is working with a recently discovered population using conservation tools like safeguarding , propagation, and working with the landowner to ensure proper management of the natural site of this population.

Montane Long Leaf Pine

montane long leaf pineThe Long Leaf Pine is Alabama’s State Tree. It is restricted to the Coastal Plain for most of its range, but in Alabama and Northwest GA, it creeps up the mountain to create a fire tolerant ecosystem unlike any other in the Appalachian range, and unlike the tree’s habitats on the flat plains to the south.