Forest Relics

Forests of mature baldcypress trees are still found in the Mississippi River bottoms as far north as Illinois and in the vast freshwater Okefenokee Swamp of the Southeast. Old stands of this species also occur in the Bay Lake area of North Carolina. In the 1900s, one stand was reported to be 650 years old. Within that stand some stems were believed to be over 1000 years old. Trees there tallied as tall as 130 feet and 10 feet in diameter.18

Another virgin stand, this of pondcypress, was once claimed to be more than 250 years old. But that was before we learned the risk for this species in determining age by ring counts. Aging by this method is unreliable. False rings, due to periodic growth fluctuation in turn caused by

Figure 3.5 Estuaries that periodically flood. Note the high-water marks on the baldcypress trees in this 1920 photograph of a southern Louisiana scene. (USDA Forest Service photo)

variations in soil moisture and aeration, are common. False rings occur with rising water following periods of drought, when the tree behaves as though winter dormancy had ended, and springwood again forms. Increment cores extracted from opposite sides of a tree, varying by as much as 10%, indicate the presence of false rings. Cores taken above the butt swell, sliced down the middle, and examined under 20-power magnification are apt to tell a reasonably accurate story. The true summerwood appears as a narrow band of small, thick-walled cells; false rings disappear, being especially indistinct when the cross-section is magnified.

In contrast to the ancient relict noted above, a North Mississippi forest may be typical, although second-growth baldcypress forests vary greatly in stand density and volume. At age 85 years, trees averaged 18 inches dbh and 112 feet tall. The stand had grown about 0.6 cord per acre per year.19

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