This is an interesting form whose leaves have rounded lobes . It appears to set fruit rarely or never. The degree of fall color varies widely each year; in addition the tree can develop narrow branch crotch angles and a more open habit. Due to its non-fruiting habit, it may be a viable choice for warmer zones.
Common Names in English:
Fruitless Sweetgum, Round-Lobed Sweetgum, Roundleaf Sweetgum, Seedless Sweet Gum
or deciduous, hermaphroditic
, andromonoecious, or monoecious. Indumentum usually of stellate
or stellate or peltate scales
. Buds perulate or naked. Leaves distichous or spiral
, rarely subopposite or opposite, stipules minute to large, usually paired
(solitary and enclosing bud in Mytilaria, and apparently absent in Rhodoleia) ; petiole
usually well defined; leaf blade
or palmately lobed
, pinnately veined or palmately 3 5-veined. Inflorescences usually spikes or heads
, rarely racemes
or (condensed) thyrses
or panicles, axillary
. Flowers small to medium-sized, bracteate
and often bracteolate
or rarely zygomorphic (Rhodoleia), hypogynous to epigynous
, floral cup
shallow to urn-shaped, sometimes absent; sepals 4 or 5( 10), sometimes absent, imbricate, usually persistent
; petals absent or 4 or 5, yellow, white, greenish or red, often ribbonlike and circinate
in bud, caducous
; stamens 4, 5, or many, free
, rarely arranged in 2 whorls with the inner whorl staminodal, development of polyandrous
androecia centripetal or centrifugal
, thecae mostly bisporangiate
, each opening by two valves
or a simple longitudinal slit, or monosporangiate and opening by a single valve
(Exbucklandia, Hamamelis and the genera of the S hemisphere), connective
protruding; disk scales sometimes present between stamens and carpels. Ovary 2-locular, carpels free at apex; ovules mostly 1 per carpel, less often many, but then most of them sterile
, crassinucellar, bitegmic, anatropous
, halfway between apotropous
, pendent from ovary top if solitary, along the carpellary margins
; placentation axile
. Styles and stigmas 2. Fruit a capsule, dehiscing septicidally, septifragally, or loculicidally and 4-valved; endocarp woody or leathery, usually loose
from leathery exocarp
. Seeds 1 to many per carpel; if solitary then seed coat
thick, hard, smooth
and shiny, black or brown; if numerous then sometimes winged
and only a few viable. Endosperm thin; embryo straight; cotyledons leaflike, radicle short.
About 30 genera and 140 species: E and S Africa (including Madagascar), E, W, and SE Asia, NE Australia, Central, North, and South America, Pacific Islands; 18 genera (four endemic) and 74 species (58 endemic) in China.
Several genera and species need critical revision .
or with simple
gray-brown, deeply furrowed
; liquid, and Arabic ambar, amber] twigs
and branches sometimes corky-winged. Dormant
, shiny, resinous, sessile. Leaves long-petiolate. Leaf blade
fragrant when crushed, (3-) 5(-7) -lobed, palmately veined, base
deeply cordate to truncate
glandular-serrate, apex of each lobe
long-acuminate. Inflorescences terminal
, many-flowered heads
heads in pedunculate
, each head a cluster
of many stamens; pistillate
heads pendent, long-pedunculate, the flowers ± coalesced
. Flowers unisexual
, staminate and pistillate on same plant, appearing with leaves; calyx and corolla absent. Staminate flowers
dehiscing longitudinally; staminodes absent. Pistillate flowers pale
green to greenish yellow; staminodes 5-8; styles indurate
in fruit, incurved
. Capsules many, fused at base into long-pedunculate, spheric, echinate
heads, 2-beaked, glabrous, septicidal
. Seeds numerous
, mostly aborting, 1-2 viable in each capsule, winged
Species 3(-4) : North America, e Asia, and Turkey.
ID Features: Distinguish from maples because leaves are alternate. Aromatic foliage. Distinct shiny fruit balls. Star shaped pith. Relatively large terminal and flower buds. Corky ridges on stems (often absent). For young trees habit is distinctly pyramidal.
Flowers: Monoecious. Yellowish-green in May. Not showy. • Bloom Period: March.
Foliage: Summer foliage: Alternate "maple-like" star shaped leaves. Leaves are 5- to 7- lobed , 4 to 8" long and wide. Margins serrate. Dark to medium glossy green. Camphor odor when crushed. • Fall foliage: Typically quite showy on most individuals. Best trees are orange, red, burgundy, and purplish. Some trees drop leaves yellow and green.
Growth Rate: Fast. • Size: Fast growing to 40 to 50 ft . high, 25 to 30 ft. wide.
Landscape Uses: Lawn tree or shade tree for larger residences. For fall color. Street tree where ample room is provided. Parks and campuses. • Liabilities: Chlorosis on high pH soils. Lack of cold hardiness , especially young trees . Because of wide geographical range it is important to use northern seed. sources for trees in New England or the Northeast. Has a shallow root system . Spiny fruit balls can be a litter problem. • Care: Follow a regular watering schedule during the first growing season to establish a deep, extensive root system . Watering can be reduced after establishment. Feed with a general purpose fertilizer before new growth begins in spring .
Culture: Prefer deep, moist, bottomland soils. Best in full sun , does okay in partial shade. Transplant B&B due to fleshy , coarse root system . Use larger plants when transplanting in colder areas to avoid cold injury. to twigs .
Soil: Moist, slightly acidic soil. Tolerates wet soils. • Minimum pH: 6.1 • Maximum pH: 7.5
Sunlight: Sun Exposure: Full sun
Moisture: Water Requirements: Once established needs only occasional water.
- Whittaker & Margulis,1978
- Haeckel, 1866
- Cavalier-Smith, 1981
- Sinnott, 1935 ex Cavalier-Smith, 1998
- Vascular Plants
- Kenrick & Crane, 1997
- Brongniart, 1843
- Takhtajan, 1967
- Takhtajan, 1967
- Dumortier, 1829
- Family: Hamamelidaceae () - R. Brown, 1818 - witch hazel
- Order: Saxifragales () - Dumortier, 1829
- Superorder: Hamamelidanae () - Takhtajan, 1967
- Subclass: Hamamelididae () - Takhtajan, 1967
- Class: Spermatopsida () - Brongniart, 1843
- Infraphylum: Radiatopses () - Kenrick & Crane, 1997
- Subphylum: Euphyllophytina ()
- Phylum: Tracheophyta () - Sinnott, 1935 ex Cavalier-Smith, 1998 - Vascular Plants
- Subkingdom: Viridaeplantae () - Cavalier-Smith, 1981
- Kingdom: Plantae () - Haeckel, 1866 - Plants
Publishing author : Rehder Publication : J. Arnold Arbor . 12: 70, fig 1931 .
Members of the genus Liquidambar
ZipcodeZoo has pages for 20 species, subspecies, varieties, forms, and cultivars in this genus:
L. acalycina (Changs Sweetgum) · L. formosana (Formosa Sweetgum) · L. formosana 'Afterglow' (Formosa Sweetgum) · L. orientalis (Oriental Sweetgum) · L. styraciflua (American Sweetgum) · L. styraciflua f. rotundiloba (Fruitless Sweetgum) · L. styraciflua var. macrophylla (Sweetgum) · L. styraciflua 'Aurora' (Aurora Sweetgum) · L. styraciflua 'Burgundy' (Burgundy Sweetgum) · L. styraciflua 'Cherokee' (Red Gum) · L. styraciflua 'Corky' (Corky Sweetgum) · L. styraciflua 'Festival' (Festival Sweetgum) · L. styraciflua 'Gold Dust' (Red Gum) · L. styraciflua 'Grazam' (Grandmaster Sweetgum) · L. styraciflua 'Gumball' (Red Gum) · L. styraciflua 'Palo Alto' (Palo Alto Sweetgum) · L. styraciflua 'Silver King' (Red Gum) · L. styraciflua 'Slender Silhouette' (Red Gum) · L. styraciflua 'Variegata' (Golden Variegated Sweetgum) · L. styraciflua 'Ward' (Ward Cherokee Sweetgum)
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- Chang Hung-ta. 1979. Hamamelidaceae. In: Chang Hung-ta, ed., Fl. Reipubl. Popularis Sin. 35(2): 36116.
- Bogle, A. L. 1986. The floral morphology and vascular anatomy of the Hamamelidaceae: Subfamily Liquidambaroideae. Ann. Missouri Bot. Gard. 73: 325-347.
- Duncan, W. H. 1959. Leaf variation in Liquidambar styraciflua L. Castanea 24: 99-111.
- Hill, A. F. 1952. Economic Botany. New York.
- Holm, T. 1930. Leaf-variation in Liquidambar styraciflua L. Rhodora 32: 95-105.
- Sargent, C. S. 1890-1902. The Silva of North America.... 14 vols. Boston and New York. Vol. 5, pp. 7-12.
- Schery, R. W. 1952. Plants for Man. New York.
- Schmitt, D. 1966. Pistillate inflorescence of sweetgum (Liquidambar styraciflua L.). Silvae Genet. 15(2): 33-35.
- Wilson, P. 1905. Altingiaceae: Liquidambar. In: N. L. Britton et al., eds. 1905+. North American Flora.... 47+ vols. New York. Vol. 22, p. 189.
- Brands, S.J. (comp.) 1989-present. The Taxonomicon. Universal Taxonomic Services, Zwaag, The Netherlands. Accessed March 27, 2012.
- Merrifield Garden Center, Fairfax VA USA
- The International Plant Names Index. Accessed Dec 27, 2011.
- Globally Unique Identifier: urn:lsid:ipni.org:names:141360-2
- International Plant Names Index (IPNI) ID: 141360-2
- Zipcode Zoo Species Identifier: 1269292
- Zhi-Yun Zhang, Hongda Zhang & Peter K. Endress "Hamamelidaceae". in Flora of China Vol. 9 Page 18. Published by Science Press (Beijing) and Missouri Botanical Garden Press. Online at EFloras.org. [back]
- "Liquidambar". in Flora of North America Vol. 3. Oxford University Press. Online at EFloras.org. [back]