This southeastern species is typical of deep swamps and pond margins; it has also become widely planted on less wet sites, and it is tolerant of eutrophic conditions (e.g. Belt 2015). Several records are mapped here as uncertain (open dots). Outlying records in c. Ky. may be from recently adventive or planted individuals. In a few cases only seedlings have been found. Not mapped are the mature trees in FAYE, JESS, SCOT and WOOD, which are probably planted (Gm), although sometimes interpreted as native (Meijer 1976b) or adventive (CW). A coll. from FULT (EKY) has suggested T. ascendens Brong. (= T. distichum var. imbricarium (Nutt.) Croom); see BA and CW. However, that taxon appears restricted to the southeastern Coastal Plain, without extending far up the Mississippi Valley (FNA 2). Some colls. are difficult to distinguish (J), and there is some intergradation further south. The genus Taxodium has cones that shatter during winter into scales, each bearing (1-)2 irregularly 3-angled, wingless seeds; these scales can disperse through flotation (Schneider & Sharitz 1988). Planted trees of the related Chinese species, Metasequoia glyptostroboides Hu & W.C. Cheng, are sometimes confused with Taxodium but closer to Sequoia. Without cones, Metasequoia can be distinguished by its leaves, which are generally longer (mostly 1-2 cm versus 0.5-1.5 cm) and strictly opposite on lateral branchlets (versus alternate); also these branchlets are opposite to subopposite along the leading shoots (versus mostly alternate). Also, Metasequoia lacks the woody "knees" above ground from roots, which are typical of mature Taxodium trees. In both genera, the whole branchlets are deciduous. The more closely related Cryptomeria japonica D. Don has spiral, subulate, quadrangular to subterete leaves. It is also planted as an ornamental in Ky., but leaves often turn brown in winter; it is from a more warm temperate climate in East Asia, with little or no naturalization across North America (FNA 2, K, W);