Baldcypress

Baldcypress14 was recognized by early observers with fascination. Lyell, the pioneering botanical explorer, said the species "gave a somber tone to scenery when hung with moss.''15 Its ghostlike appearance in winter, without foliage (thus bald), conjures a foretaste of gloom.

Unique among the South's needleleaf trees because of its deciduous nature, baldcypress grows in luxurious stands along the "red" rivers that originate in the Piedmont and mountains and, from those regions, carry silt and clay to the sea. The species does equally well in black backwaters of the Coastal Plain, which carry little mineral sediment but much suspended organic lignin, the slowly decaying component of the wood that lies rotting in the region's woodlands and subsequently leaches to streams. Stands are also common in muck swamps and sloughs that border the hardwood "ridges" of deep alluvial soil. Although the species grows best in mesic sites characterized by deep, moist, fine sandy loam, severe competition by other vegetation discourages survival on such sites.

Figure 3.4 Mature baldcypress trees in a deep-water lake. The site had drained naturally sometime in the past at the time of seedfall, thus allowing for seed germination and seedling survival. Sometime after the seedlings were well established, the water level rose to depths even greater than that shown here.

Figure 3.4 Mature baldcypress trees in a deep-water lake. The site had drained naturally sometime in the past at the time of seedfall, thus allowing for seed germination and seedling survival. Sometime after the seedlings were well established, the water level rose to depths even greater than that shown here.

Baldcypress is thus confined to the wetter areas where few other trees are able to compete to survive. Seedlings grow well even under partial shade.

Interwoven with pure stands of baldcypress are those of pondcypress, a botanical variety of the former about which there is much confusion. The smaller pondcypress of a lesser range and with ascending branchlets, occurs in denser stands that give it a slender erect appearance. This characteristic and the tree's sometimes sky-reaching branching habit perhaps influenced the assignment of its scientific name: var. ascendens.16

Pondcypress occurs on sand-bottom sites and in highly acid "pine barren" ponds in company with both pond and spruce pines. In contrast, marl-underlain soil along some rivers is not conducive to pondcypress growth, but does support baldcypress. On the other hand, the presence of the typical variety, rather than ascendens, could be attributed to the availability of seeds and an appropriate water level at the time of seed germination, rather than to a preference for a particular site.

Ecological pioneers, these trees become established when water is low in one or more extremely dry seasons following periods of sufficient moisture for soaking the soil for one to three months. A saturated, but not inundated, seedbed is essential for seed germination. Natural reproduction may come in after drainage of open cypress stands. Both bald- and pondcypress varieties occur in pure even-aged stands or in mixtures with many broadleaf trees.

The swamps in which these trees occur are especially important for groundwater recharge and wildlife habitat. Riverine swamps cause floodwaters to spread out, slow down, infiltrate the surface soil, and percolate through the soil profile, thereby reducing flood damage.

Stands generally recover to their original composition following clearcutting. Vegetative reproduction in the form of sprouts accompanies the natural seedlings. The sprouts themselves produce cones in two years. In Florida, where cypress swamps compose more than 25% of the commercial forest, biomass returned to merchantable levels within about 50 years following logging during the first half of the 20th century. 17

Micro-sites for regeneration are the tree bases and residual knees of old trees on which typical bay shrubs and trees encroach to form "islands." These small areas of slightly elevated land supporting shrubby vegetation unite to form a solid organic surface covering ponded areas. Vast root systems of bay shrubs along the edge of the pond aid in the development of the islands, which also may be portions of original shorelines that have not been destroyed by erosion.

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