The Original Mystery Plant

Photo contributed by the USC Herbarium

If you visit central South Carolina, you will want to visit our Congaree National Park, one of the most breathtaking places in the world.

It boasts an impressive diversity of plants and wildlife, especially migratory birds. Some of its acreage is dominated by tracts of land never before timbered, and thus, some of eastern North America's tallest forests are here.

The tiny human beings at the base of this tree are members of my current plant taxonomy class at USC. I gathered my flock around this forest giant, and we spent some time wondering how come such monstrous trees occur so close by.

This tree is a conifer, and produces plenty of cones. Male and female cones are on the same tree. The male cones are a little over an inch long, skinny and shaped like little yellow worms.

The seed cones are much larger than the pollen cones and take two years to mature. The opened seed cones have plenty of overlapping, elongated scales, and on the upper surface of each scale, two winged seeds will develop. This is a potentially tall tree, easily able to reach 140' tall on good sites.

It was originally at home mostly on the coastal plain, but due to land disturbance has managed to find its way well into the piedmont. These days it can be found from Maryland south to northern Florida and eastern Texas. Because it has been widely grown in extensive plantations for many years, its natural range has considerably increased, due to the tendency of its seeds to travel well away from the parent tree.

This tree is nearly 170 feet tall and is surely one of the largest of its kind anywhere. Curiously, we saw no seedlings or young individuals. This tree's canopy is quite healthy, and is still producing plenty of cones. The seedlings of this species are rather intolerant of shade and die soon after sprouting. Therefore, no small or medium- sized trees are here, only these giants.

How did this tree get here in the first place? The prevailing notion is that long ago, the bottomlands along the Congaree River were subjected to repeated devastating wind storms that effectively removed whatever canopy was present.

Seeds drifting in from higher ground sites would have been the source for the forest giants present now. Although they are producing seeds, they are not propagating any replacement trees. That means, when these venerable old behemoths eventually die and fall over, there will not be another generation of replacements, or at least not until after the next series of hurricanes. Answer to this week's mystery plant

Answer: "Loblolly pine," Pinus taeda

Dr. John Nelson is the curator of the USC Herbarium.

To learn more about the Herbarium, call 777-8196. The

department also offers free plant identification.

www.herbarium.org