Bald cypress (Taxodium distichum): what the agencies record

This page reports what US federal publications say about one tree. It does not identify trees from descriptions or photos and does not say what should be done with any tree. The family overview, tree species in the agency records, explains the sources and holds the comparison table.

At a glance

Item	What the source records
Scientific name	Taxodium distichum (L.) Rich., redwood family as Silvics files it; a deciduous conifer
Varieties, Silvics	Variety distichum (baldcypress) and variety nutans (pondcypress)
Native status, USDA PLANTS	Native in the lower 48 states; no Canadian status listed
Size, Silvics	Largest trees in virgin forests 215 to 365 cm (84 to 144 in) in diameter and 43 to 46 m (140 to 150 ft) tall; the champion in Louisiana, in the 1982 national register, 520.7 cm (205 in) in diameter and 25 m (83 ft) tall
Green weight of the wood, NRS-38	51 lb per cubic foot, without bark

Native range and flooded sites

The Silvics of North America handbook (Agriculture Handbook 654, Volume 1, 1990) says baldcypress grows on saturated and seasonally flooded soils of the Southeastern and Gulf Coastal Plains. The range runs along the lower Atlantic Coastal Plain from southern Delaware to southern Florida and along the lower Gulf Coastal Plain to southeastern Texas. Inland it grows along streams of the middle and upper coastal plains and north through the Mississippi Valley to southeastern Oklahoma, southeastern Missouri, southern Illinois and southwestern Indiana. The handbook says more than 90 percent of natural stands are on flat ground or in slight depressions below 30 m (100 ft) above sea level, with floodwaters that may be 3 m (10 ft) deep or more. It says the tree cannot tolerate water with more than 0.89 percent salt, and that baldcypress trees planted in the northeastern United States and southern Canada withstand winter minimums of minus 29 to minus 34 degrees C.

Pondcypress, variety nutans, grows from southeastern Virginia to southern Florida and southeastern Louisiana, almost always below 30 m (100 ft). Silvics says it occupies shallow ponds and poorly drained areas and rarely grows in river and stream swamps, on more acid and much less fertile sites than baldcypress. It says pondcypress is less likely than baldcypress to have knees, and that it is often difficult and sometimes impossible to tell the varieties apart.

Cones, seed and sprouting

The species is monoecious. The handbook says male catkins, in slender purplish drooping clusters 7 to 13 cm (3 to 5 in) long, are conspicuous in winter on this deciduous conifer, with pollen shed in March and April. Globose cones, 13 to 36 mm (0.5 to 1.41 in) across, turn from green to brownish purple as they mature from October to December. Good seed crops come at 3 to 5 year intervals, and floodwaters are the most important means of seed spread. Seeds will not germinate under water, though some stay viable for 30 months under water, and the handbook says a soil saturated but not flooded for 1 to 3 months after seedfall is required. It calls baldcypress one of the few conifers that sprout, from stumps of young trees and, if cut in fall or winter, trees up to 60 years old.

Age, growth and roots

Silvics says baldcypress is reputed to be slow growing and very long-lived, but many trees put on more than one false ring in some seasons, so that conventional ring counts in one plantation study averaged 1.6 times the actual age. An earlier investigator concluded that trees 400 to 600 years old were common in virgin stands and that a few reached 1,200 years. The handbook says stems generally need 200 years in forest conditions to yield a high proportion of heartwood lumber, that height growth ceases at age 200, and that after this age many trees slowly die back from the top as a fungus-caused rot moves down the stem. Seedlings develop a taproot, and older swamp trees develop several descending anchor roots and lateral roots that send up conical knees from several centimeters to more than 3.7 m (12 ft) tall. The handbook says research has found no physiological function for knees, that they may help aeration and anchorage, and that the root system with its buttressed base makes the tree windfirm: even hurricane-force winds rarely overturn it.

Wood

The Wood Handbook (FPL-GTR-282, 2021) says the sapwood is narrow and nearly white and the heartwood ranges from light yellowish brown to dark brownish red or chocolate. The wood is moderately heavy, moderately strong and moderately hard, with moderately low shrinkage. It says the heartwood of old-growth baldcypress is one of the most decay-resistant of US species while second-growth wood is only moderately resistant. Uses it lists include building construction, caskets, sashes, doors, tanks, vats, ship and boat building and cooling towers, and for second growth siding and millwork. It describes pecky cypress, wood with pockets attacked by a fungus, as durable where water tightness and appearance do not matter.

Wood Handbook figure	Green	At 12% moisture content
Specific gravity (Table 5-3b)	0.42	0.46
Modulus of rupture, lbf per square inch (Table 5-3b)	6,600	10,600
Side hardness, lbf (Table 5-3b)	390	510

The green weight is in the NRS-38 table, the same figure used in the log weight calculator.

Fungi and insects the handbook names

Pecky cypress fungus. Silvics says Stereum taxodii causes a brown pocket rot in the heartwood of living trees, especially overmature ones, entering usually through the crown, and that its action stops when the tree is felled. A few other fungi attack sapwood and heartwood and a few needle and twig fungi are reported, none known to cause serious damage.
Defoliators. The fruit tree leafroller, which the handbook says became epidemic in 1983 in the lower Atchafalaya Basin of Louisiana, with dieback in repeatedly defoliated trees; the cypress looper; the cypress flea beetle; and the bagworm, described on the bagworm page.
Bark and cone insects. The southern cypress bark beetle tunnels beneath the bark of limbs and trunks, and the baldcypress coneworm can destroy more than 75 percent of a single year's cone crop.
Animals. Nutria clip or uproot newly planted seedlings, and deer and swamp rabbits clip seedlings, which generally resprout.

For who takes reports of regulated pests, see reporting a pest in the United States, and pests and diseases by country sets out which ones agencies regulate.