BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Liquidambar styraciflua | Sweetgum 



GENERAL BOTANICAL CHARACTERISTICS : 
Sweetgum is a large, native, long-lived, deciduous tree that reaches
heights of 50 to 150 feet (15-45 m) at maturity [6,14].  It is easily
recognizable by the long-petioled, star-shaped leaves which have five
long-pointed, saw-toothed lobes. The brown bark is deeply furrowed into
narrow scaley plates or ridges.  Young sweetgum trees have long conical
crowns, while mature trees have crowns that are round and spreading.
Sweetgum is monoecious with the male flowers in several clusters and the
female flowers hanging at the end of the same stalk.  The ball-shaped
fruits contain many individual seed-bearing sections, and persist
throughout the winter [16,18].


RAUNKIAER LIFE FORM : 
   Phanerophyte


REGENERATION PROCESSES : 
Seed production and dissemination:  Sweetgum produces an abundance of
lightweight seed.  The tree begins to produce seed when 20 to 30 years
old, and crops remain abundant for 150 years.  Fair seed crops are
produced each year, with bumper crops every 2 to 3 years [2,24].  Under
conditions of full sunlight and rich moist soil, each fruit may average
as many as 50 sound seeds. Seed is primarily dispersed by wind; the
maximum dispersal distance recorded was 600 feet (183 m) but
ordinarily 96 percent of the seed fall within 200 feet (61 m) of the
point of release [24,38].

Seedling development:  Sod is not a serious hindrance to seed
germination; however, when additional sweetgum production is desired in
partially cutover stands, exposed mineral soil and abundant direct
sunlight are necessary [4,22].  Root development varies with the growing
site.  A deep taproot and numerous horizontal rootlets usually develop
early, but in wet areas the root sytem is shallow and wide spreading,
with little or no taproot [25,39].  On an abandoned field adjacent to a
swamp in Maryland, 5-year-old seedlings averaged 8.7 feet (2.6 m) in
height [24].  On favorable sites in the lower Mississippi Valley,
seedlings grow as much as 2 feet (0.6 m) during the first year [24,49].

Vegetative reproduction:  Sweetgum is capable of sprouting until it is
approximately 50 years old.  Although sweetgum seedlings reach a height
of 4.5 feet (1.4 m) in 3 to 5 years, sprouts often reach this height in
one growing season.  Ten-year old sprouts frequently have the same size
and appearance as 18- to 20-year-old seedlings in the same stand
[23,49].


SITE CHARACTERISTICS : 
Sweetgum is very tolerant of different soils and sites but grows best on
the rich, moist, alluvial clay and loamy soils of river bottoms [28].
Throughout the Piedmont Plateau, sweetgum shows good growth on river and
stream bottoms and shows considerable potential on many upland sites
[24,34].

Common tree associates of sweetgum include spruce pine (Pinus glabra),
Virginia pine (P. virginiana), red maple (Acer rubrum), box elder (A.
negundo), pignut, shellbark, shagbark, and mockernut hickories (Carya
glabra, C. laciniosa, C. ovata, C. tomentosa), and sugarberry (Celtis
laevigata).  Common understory associates include dogwood (Cornus spp.),
alder (Alnus spp.), and eastern redbud (Cercis canadensis) [1,10,24].


SUCCESSIONAL STATUS : 
Sweetgum is classified as shade intolerant [7].  In pure stands on
bottomland sites, young sweetgum is able to endure some shade and
crowding.  With increase in age the tree becomes less tolerant of
competition.  Following natural decrease in the canopy, enough sunlight
reaches the ground to permit an understory stand to develop [12,24].
Although sweetgum is an early invader, it seldom becomes a dominant
species [20,31].


SEASONAL DEVELOPMENT : 
Sweetgum flowers appear from March to May, depending on latitude and
weather.  The fruit ripens from September to November; the fruit often
persists through the entire winter [6,24].

Related categories for Species: Liquidambar styraciflua | Sweetgum