Aboveground description: Sweetbay normally grows as a multistemmed shrub or slender tree in the Northeast and as a single-trunked tree in the Southeast . In its more northern distribution, sweetbay may be only 33 to 66 feet (10-20 m) tall, and in its southern distribution, sweetbay may grow to 98 feet (30 m) tall and 3.9 feet (1.2 m) DBH [33,38,43,99]. In the northernmost sweetbay population of Massachusetts, clumps averaged 12 feet (3.6 m) tall . An exceptionally large tree in Mississippi was 83 feet (25 m) tall and had a 31-inch (79 cm) diameter and a 98-inch (249 cm) circumference . Sweetbay crown spread is typically 10 to 20 feet (3-6 m) . Although Alden  reports that sweetbay grows slowly, Phillips  suggests that sweetbay may reach "full size" in less than 30 years. In the Big Thicket National Preserve of Texas, radial growth of sweetbay trees with a DBH exceeding 1.8 inches (4.5 cm) averaged 0.24 cm/year in a little bluestem (Schizachyrium scoparium) meadow and 0.26 cm/year in a closed-canopy mixed pine-oak (Pinus-Quercus spp.) forest . Little  estimated that sweetbay lives approximately 130 years.
Systematists describe sweetbay as "tardily deciduous" to evergreen . Distribution and climate determine leaf deciduousness which ranges from evergreen in the Southeast to deciduous in the Northeast. Sweetbay leaves are glossy above, silky white or gray below, and have a leather-like texture. Leaves measure 3.2 to 5.9 inches (8-15 cm) long with widths about half that [33,34,42,44,110,141].
|Â© 2002 (flower) 2006 (fruit) Steven J. Baskauf|
Sweetbay flowers occur singly at branch ends [102,110]. Flowers have 6 to 12 petals and 2 to 3 sepals that detach soon after flowers open [44,104]. Once open, flowers measure 1.5 to 2.8 inches (4-7 cm) across . Sweetbay produces an aggregate of follicles that turn bright red in the fall . Fruiting cones measure 0.8 to 2 inches (2-5 cm) long and nearly as wide. Seeds are generally 6 to 9 mm long [44,104] and drop soon after maturation . Seeds may fall individually or as a cone .
Belowground description: While direct observations and/or excavation studies of sweetbay rooting depth and root spread were lacking, some fire effects studies partially describe belowground structures. Sprouting after top-kill has been reported from root crowns, roots [111,137], and/or underground lignotubers . In some cases, sweetbay roots may grow partially above ground. In bay swamps of Georgia, surfaces are irregular and "roots may be exposed and highly convoluted" . In the Okefenokee swamp, high sweetbay mortality after fire was partially attributed to the death of aboveground roots (Hopkins 1947, as cited in ).
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