Life History and Disturbance Response of Liquidambar styraciflua (sweetgum)
Family: Hamamelidaceae
Guild: opportunistic, long-lived intolerant
Functional Lifeform: medium-size to large deciduous
tree
Ecological Role: grows best on moist, alluvial
soils but tolerates a wide range of site conditions; colonizes old fields
and logged areas; often present in the understory of pine forests
Lifespan, yrs (typical/max): 200/300
Shade Tolerance: intolerant
Height, m: 15-45
Canopy Tree: yes
Pollination Agent: wind
Seeding, yrs (begins/optimal/declines): 20/30/150
Mast Frequency, yrs: 3
New Cohorts Source: seeds or sprouts
Flowering Dates: early spring
Flowers/Cones Damaged by Frost: yes
Seedfall Begins: early fall
Seed Banking: up to 1 yr
Cold Stratification Required: yes
Seed Type/Dispersal Distance/Agent: winged/ to
100 m/ wind
Season of Germination: spring
Seedling Rooting System: variable
Sprouting: stump sprouts and root suckers common
Establishment Seedbed Preferences
Substrate: variable
Light: overstory shade
Moisture: moist required
Temperature: neutral
Disturbance response:
Fire: Fires are unusual in the moist bottomlands
where sweetgum grows. Sweetgum is not favored by fire. It has thin bark
and is readily damaged or topkilled by fire. Sweetgum trees sprout prolifically
from the root crown following fire, but repeated annual growing season
burns will eventually deplete carbohydrate reserves and kill the plant.
Dormant season fires are less damaging than growing season fires. Fire
scars may be entry points for insects and diseases, but as long as the
sapwood is not killed, basal wounds are often covered with a protective
gum exudate. After repeated fires, sapwood may be killed and fungi and
insects become established. Seedling establishment may occur from seeds
of surviving trees onsite or from offsite seeds carried by wind. Prescribed
burning in the growing season may be useful for controlling sweetgum where
it is not a desirable species.
Weather: Sweetgum is very windfirm on upland sites.
Air pollution: Sweetgum is intermediate to sensitive to ozone. Symptoms
of foliar injury have been noted in areas of high ambient ozone. Seedlings
exhibited reduced height growth and biomass accumulation under controlled
fumigation with ozone.