Edward F. Gilman, Dennis G. Watson, Ryan W. Klein, Andrew Ok. Koeser, Deborah R. Hilbert, and Drew C. McLean2
Sweetgum grows in a slim pyramid to a peak of 75 toes and should unfold to 50 toes. The superbly shiny, star-shaped leaves flip shiny purple, purple, yellow or orange within the fall (USDA hardiness zones 6 and seven) and early winter (USDA hardiness zones Eight and 9). On some timber, significantly within the northern a part of its vary, branches are coated with attribute corky projections. The trunk is generally straight and doesn’t divide into double or a number of leaders and aspect branches are small in diameter on younger timber, making a pyramidal kind. The bark turns into deeply ridged at about 25-years-old. Sweetgum makes a pleasant conical park, campus or residential shade tree for giant properties when it’s younger, growing a extra oval or rounded cover because it grows older as a number of branches grow to be dominant and develop in diameter.
Scientific identify: Liquidambar styraciflua
Pronunciation: lick-wid-AM-bar sty-rass-ih-FLOO-uh
Widespread identify(s): sweetgum
USDA hardiness zones: 5B via 10A (Fig. 6)
Origin: native to North and Central America
UF/IFAS Invasive Evaluation Standing: native
Makes use of: tree garden > 6 ft vast; shade; road with out sidewalk; specimen; reclamation; car parking zone island > 200 sq ft
Peak: 60 to 75 toes
Unfold: 35 to 50 toes
Crown uniformity: symmetrical
Crown form: pyramidal, oval
Crown density: average
Progress price: average
xLeaf association: alternate (Determine 2)
Leaf kind: easy
Leaf margin: serrate
Leaf form: star-shaped
Leaf venation: palmate
Leaf kind and persistence: deciduous
Leaf blade size: Four to six inches
Leaf colour: darkish inexperienced and glossy on prime, whitish inexperienced beneath
Fall colour: yellow, orange, purple, burgundy
Fall attribute: showy
Flower colour: yellow inexperienced or tinged with purple
Flower traits: not showy; male – emerges in clusters on a 3-4” lengthy, upright raceme; feminine – emerges in clusters on a ½” lengthy, globulose head that hangs from a skinny stalk
Flowering: early to mid-spring
Fruit form: spherical (Fig. 8)
Fruit size: 1 to 1 ½ inches
Fruit masking: dry or exhausting; spiny, spherical cluster of beaked capsules
Fruit colour: brown
Fruit traits: attracts birds; showy; fruit/leaves a litter drawback
Trunk and Branches
Trunk/branches: branches droop; not showy; usually one trunk; no thorns
Bark: grayish brown, deeply furrowed, with tough, interlacing ridges that grow to be virtually white with age
Pruning requirement: little required
Present 12 months twig colour: reddish, brown
Present 12 months twig thickness: medium
Wooden particular gravity: 0.52
Mild requirement: full solar to partial shade
Soil tolerances: clay; sand; loam; acidic; barely alkaline; moist to well-drained
Drought tolerance: average
Aerosol salt tolerance: average
Roots: can kind giant floor roots
Winter curiosity: sure
Excellent tree: no
Ozone sensitivity: delicate
Verticillium wilt susceptibility: resistant
Pest resistance: proof against pests/illnesses
Use and Administration
Watch out when finding Sweetgum as a road tree since its giant, aggressive roots could carry curbs and sidewalks. Plant timber Eight to 10 toes or extra from curbs. Some communities have giant numbers of Sweetgum planted as road timber. A lot of the foundation system is shallow (significantly in its native, moist habitat), however there are deep vertical roots immediately beneath the trunk in well-drained and in another soils. The fruit could also be a litter nuisance to some within the fall, however that is often solely noticeable on exhausting surfaces, akin to roads, patios, and sidewalks, the place folks may slip and fall on the fruit. The cultivar `Rotundiloba’ is fruitless. The tree ought to be planted solely in soil with a pH of seven or much less. The seeds present meals for wildlife and can typically readily germinate in shrub and groundcover beds, requiring their elimination to take care of a neat panorama look. Tree thickets kind on this method, creating dense monocultures of Sweetgum.
Though it grows at a average tempo, Sweetgum isn’t attacked by pests, and tolerates moist soils, however chlorosis is commonly seen in alkaline soils. Bushes develop properly in deep soil, poorly in shallow, droughty soil. It’s troublesome to transplant and ought to be planted from containers or transplanted within the spring when younger because it develops deep roots on well-drained soil. It’s native to bottomlands and moist soils and tolerates just some (if any) drought. Present timber typically die-back close to the highest of the crown, apparently attributable to excessive sensitivity to building harm to the foundation system, or drought harm. The tree leafs out early within the spring and is usually harm by frost.
Cultivars have been chosen for his or her fall colour, leaf form, or development behavior: `Burgundy’ – lovely, shiny inexperienced leaves, burgundy purple fall colour, holds leaves late into fall, slim pyramid, much less chilly hardy, extra tailored to the southern a part of its vary; `Competition’ – slim upright development behavior, peach-colored fall foliage, much less chilly hardy, extra tailored to the southern a part of the vary; `Moraine’ is reputed to be probably the most chilly hardy; `Palo Alto’ – pyramidal, symmetrical development, shiny orange fall colour; `Rotundiloba’ – spherical leaf suggestions, no fruit manufacturing, slim pyramidal kind. Liquidambar formosana has a broader spreading crown.
Bagworm makes sacks by webbing collectively items of leaves. The bugs dwell within the sacks whereas they feed. Small numbers of bugs could also be picked off by hand.
Fall webworm webs over parts of huge branches or could fully cowl small branches. The bugs feed on leaves contained in the nest. If sensible, nests may be pruned out whereas small and when the bugs are inside. A couple of nests in giant timber aren’t severe.
Leaf miner causes brown blotches on leaves. If harm is attributable to leaf miner the browned higher and decrease leaf surfaces shall be fully separate when the leaf is torn in two.
Cottony-cushion scale, Sweetgum scale, and walnut scale can infest the branches. Use horticultural oil within the spring to assist present management.
Tent caterpillars make nests to dwell in however go away the nests to feed. Prune out nests on the suggestions of small branches. Don’t burn the nest whereas it’s nonetheless within the tree as a result of you’ll injure the tree.
Sweetgum could also be attacked by canker illnesses. These illnesses trigger sunken areas on the trunk and a few trigger profuse “bleeding”. Contaminated bark and sapwood shall be brown and useless. There is no such thing as a chemical management for canker illnesses. Severely contaminated timber will die. Prune cankers out of calmly contaminated timber. Keep tree well being by watering and fertilizing.
Leaf spots of assorted varieties could assault Sweetgum, inflicting untimely defoliation, however aren’t severe. Rake up and destroy contaminated leaves to assist management if there aren’t any adjoining Sweetgum so as to add inoculum.
Chief dieback on established timber within the southern U.S. could also be attributable to lack of moisture and/or building harm.
Koeser, A. Ok., Hasing, G., Friedman, M. H., and Irving, R. B. 2015. Bushes: North & Central Florida. College of Florida Institute of Meals and Agricultural Sciences.
U.S. Division of Agriculture, UF/IFAS Extension Service, College of Florida, IFAS, Florida A & M College Cooperative Extension Program, and Boards of County Commissioners Cooperating. Nick T. Place, dean for UF/IFAS Extension.