PINE AND [HAMMOCK] RIDGE
(elevation: 3 to 7 feet above sea level)
SAWGRASS GLADES PINELAND HARDWOOD [HAMMOCK] PINELAND 1 SOUTH FLORIDA SLASH PINE 2 SAW-PALMETTO 3 COONTIE 4 SAW-PALMETTO AFTER FIRE
With the opening up of south Florida for farming and industry, man’s works—particularly roads and canals—soon crisscrossed the region, forming barriers to the spread of the fires. Suppression of fire by farmers, lumbermen, and park managers also lessened their effect. Thus the hardwoods, which previously had been held back by fire, tended to replace the pines. And although the park was established to preserve a patch of primitive subtropical America as it was in earlier centuries, the landscape began to change.
Continued protection of the park from fire would in time eliminate the pineland—a plant [community] that has little chance to survive elsewhere. So, in [Everglades] National Park, Smokey Bear must take a back seat: park rangers deliberately set fires to help nature maintain the natural scene. Thus, as you drive down the road to Flamingo, do not be shocked to discover park rangers burning the vegetation. The fires are controlled, of course, and the existing [hammocks] are not destroyed.
When you visit the park take a close look at the pinelands [community]. Notice, as you walk on the manmade trail through the pine forest, that the ground on either side of you is extremely rough. The [limestone] bedrock is visible everywhere; what soil there is has accumulated in the pits and potholes that riddle the bedrock. The trees, shrubs, grasses, and other plants are rooted in these pockets of soil.
The [limestone] looks rather hazardous to walk on—and it is. You must be careful not to break through a thin shell of rock covering a cavity. This pitted, honeycombed condition is due to the fact that the limestone is easily dissolved by acids. Decaying pine needles, palmetto leaves, and other dead plant materials produce weak acids that continually eat away at the rock.
If a fire has passed through the pineland recently, you may notice that while most of the low-growing plants have been killed, some, such as the saw-palmetto, are sending up new green shoots. The thick, stubby stem of the palmetto lies in a pothole, with its roots in the soil that has accumulated there; even in the dry season the pocket in the [limestone] remains damp, for water is never very far below the surface in this region. When fire kills the top of the plant, the stem and roots survive, and the palmetto, like the pine, remains a part of the plant [community].
A number of other plants of the south Florida pinelands have adapted to the conditions of periodic burning. Coontie (a cycad, from the underground stems of which the Indians made flour) and moon vine (a morningglory) are among many you will see surviving pineland fires severe enough to result in the death or stunting of the hardwood seedlings and saplings.
Sometimes we forget that fire—like water, wind, and sunlight—is a natural force that operates with the others to influence the evolution of plants as well as to shape the landscape.