Sweetgum (Styraciflua)

The Sweetgum (Styraciflua) is generally described as a perennial tree. This is native to the U.S. (United States) has its most active growth period in the spring and summer . The greatest bloom is usually observed in the mid spring, with fruit and seed production starting in the summer and continuing until fall. Leaves are not retained year to year. The Sweetgum (Styraciflua) has a long life span relative to most other plant species and a rapid growth rate. At maturity, the typical Sweetgum (Styraciflua) will reach up to 100 feet high, with a maximum height at 20 years of 45 feet.

The Sweetgum (Styraciflua) is easily found in nurseries, garden stores and other plant dealers and distributors. It can be propagated by bare root, container, cuttings, seed. It has a moderate ability to spread through seed production and the seedlings have high vigor. Note that cold stratification is not required for seed germination and the plant cannot survive exposure to temperatures below -21°F. has low tolerance to drought and restricted water conditions.

Uses of : Landscaping, Medicinal, Culinary, etc.

Erosion Control: Sweetgum is a good choice as a windbreak tree because of its fast growth and tolerance of a wide variety of sites.

Wildlife: Its seeds are eaten by birds, squirrels, and chipmunks.

Timber: Sweetgum is primarily used for lumber, veneer, plywood, slack cooperage, railroad ties, fuel and pulpwood. Its wood is used for veneer, furniture, interior trim, and wooden ware, in addition to pulpwood for fine papers.

Recreation and Beautification: It is used as a specimen plant, shade tree, and street tree.

General Characteristics

Liquidambar styraciflua L., sweetgum, is native to southeastern, east-central, and south-central United States, southern Mexico, and central America. It is a large deciduous hardwood tree, which can grow to over 100 feet in height and 3 to 5 feet in diameter, with a symmetrical, cone-shaped crown. The bark is grayish brown, deeply furrowed into narrow, somewhat rounded ridges. The leaves are alternate, simple, and palmately lobed with 5-7 points resembling a star in shape, dark green and lustrous above, paler underneath. Flowers are monoecious, female, on a slender stalk terminated by a ½ inch diameter globose head consisting of 2-beaker ovaries subtended by minute scales. The fruit is a dangling brown, woody spiny tipped “gum ball” with seeds brownish and winged.

Required Growing Conditions

In the wild, sweetgum grows in bottomland areas with rich, moist soil, but can tolerate a variety of soil conditions. The tree does not do well planted in locations where roots are limited in their development. It grows best on moderately coarse to fine soils that are well drained and slightly acid (pH 6.1- 6.5). It develops a deep taproot with numerous highly developed laterals on well drained bottomland sites and a shallow, wide spreading root system on poorly drained sites. Sweetgum is very intolerant to shade but tolerant to flooding. It also tolerates seaside sites if protected from high winds.

Sweetgum is distributed throughout the east and southeast portions of the United States.

Cultivation and Care

Sweetgum can regenerate naturally from root sprouts following logging. It can be successfully established using quality seedlings with a large root-collar diameter of at least ¼ inch. Mycorrhizae can significantly improve seedling quality. Soil amended with as little as ½ inch of sewage sludge (disked into the soil) can result in better growth at outplanting.Leafy cuttings taken with a heel can be readily rooted under mist in summer. Transplant balled and burlapped plants in spring into deep, moist, slightly acid soil, full sun. The root system is fleshy, not greatly fibrous, and takes a while to reestablish. Seeds exhibit only a shallow dormancy, but germination rate is considerably increased by cold, moist stratification at 41 (F for 15 to 90 days in moist sand. Prechilled seeds should be broadcast or drilled to achieve a seedling density of 20-25 per square ft. Seeds should be sown on the soil surface and lightly pressed into the soil. A mulch of sawdust, sand or chopped pine needles should be applied. There are approximately 0.8 lb of clean seeds per bushel of fruit and the average number of seeds per lb is 82,000.

General Upkeep and Control

Adequate sunlight is required for sweetgum to reach its potential. Young trees are able to withstand crowding, however, they become intolerant to competition with increasing age. Removal of overstory trees results in rapid growth of young sweetgum trees.

Pests and Potential Problems Sweetgum is susceptible to iron chlorosis on high pH soils, frost damage to late summer shoot growth, occasional bleeding necrosis, leader dieback, sweetgum blight, leaf spots, sweetgum webworm, caterpillars, cottony-cushion scale, sweetgum scale, and walnut scale.

Cultivars, Improved, and Selected Materials (and area of origin) ‘Burgundy,’ ‘Moraine,’ ‘Festival,’ ‘Obtusiloba,’ ‘Gumball,’ ‘Palo Alto,’ ‘Levis,’ and ‘Variegata.’ Sweetgum seeds are commercially available from forest seed companies.

Plant Basics
Category
Growth Rate Rapid
General Type Tree
Growth Period Spring, Summer
Growth Duration Perennial
Lifespan Long
Plant Nativity Native to U.S.
Commercial Availability Routinely Available
Physical Characteristics
Bloom Period Mid Spring
Displays Fall Colors Yes
Shape/Growth Form Single Stem
Drought Tolerance Low
Shade Tolerance Intolerant
Height When Mature 100
Vegetative Spread Moderate
Flower Color Green
Flower Conspicuousness No
Fruit/Seed Abundance Medium
Fruit/Seed Seasonality Summer Fall
Seed Spread Rate Moderate
Gardening Characteristics
Propagations (Ways to Grow) Bare Root, Container, Cuttings, Seed
Moisture Requirements High
Cold Stratification Required Yes
Minimum Temperature -21
Soil Depth for Roots 36
Toxic to Nearby Plants No
Toxic to Livestock No
After-Harvest Resprout Ability Yes
Responds to Coppicing Yes
Growth Requirements
pH Range 4.5–7 pH
Precipitation Range 40–40 inches/yr
Planting Density 300–800 indiv./acre
Soil Textures Coarse, Fine, Medium
Soil Depth for Roots 36
Minimum Frost-Free Days 180 day(s)
Salinity Tolerance None
CaCO3 Tolerance Low
Sustainability & Use
Leaf Retention No
Palatability Medium
Fire Resistant No
Causes Livestock Bloating None

Source: USDA, NRCS, PLANTS Database, plants.usda.gov.
National Plant Data Center, Baton Rouge, LA 70874-4490 USA