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Suggest pagesSorbus americana
| Sorbus americana | |
|---|---|
 |
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| Scientific classification | |
| Kingdom: | Plantae |
| (unranked): | Angiosperms |
| (unranked): | Eudicots |
| (unranked): | Rosids |
| Order: | Rosales |
| Family: | Rosaceae |
| Genus: | Sorbus |
| Section: | Commixtae[2] |
| Species: | S. americana |
| Binomial name | |
| Sorbus americana[1] Marshall |
|
The tree species Sorbus americana (syn. Pyrus americana) is commonly known as the American Mountain-ash. It is a relatively small (height 12 meters / 40 feet)[3] deciduous perennial tree, native to eastern northern North America[2].
The American mountain-ash and related species (most often the European Mountain ash, Sorbus aucuparia) are also referred to as rowan trees.
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[edit] Description
The American Mountain-ash attains its largest specimens on the northern shores of Lake Huron and Lake Superior.[4]
It resembles the European Mountain-ash, Sorbus aucuparia.
- Bark: Light gray, smooth, surface scaly. Branchlets downy at first, later become smooth, brown tinged with red, lenticular, finally they become darker and the papery outer layer becomes easily separable.
- Wood: Pale brown; light, soft, close-grained but weak. Sp. gr., 0.5451; weight of cu. ft., 33.97 lbs.
- Winter buds: Dark red, acute, one-fourth to three-quarters of an inch long. Inner scales are very tomentose and enlarge with the growing shoot.
- Leaves: (see Leaf shape for explanation of terms) Alternate, compound, odd-pinnate, six to ten inches long, with slender, grooved, dark green or red petiole. Leaflets thirteen to seventeen, lanceolate or long oval, two to three inches long, one-half to two-thirds broad, unequally wedge-shaped or rounded at base, serrate, acuminate, sessile, the terminal one sometimes borne on a stalk half an inch long, feather-veined, midrib prominent beneath, grooved above. They come out of the bud downy, conduplicate; when full grown are smooth, dark yellow green above and paler beneath. In autumn they turn a clear yellow. Stipules leaf-like, caducous.
- Flowers: May, June, after the leaves are full grown. Perfect, white, one-eighth of an inch across, borne in flat compound cymes three or four inches across. Bracts and bractlets acute, minute, caducous.
- Calyx: Urn-shaped, hairy, five-lobed; lobes, short, acute, imbricate in bud.
- Corolla: Petals five, creamy white, orbicular, contracted into short claws, inserted on calyx, imbricate in bud.
- Stamens: Twenty to thirty, inserted on calyx tube; filaments thread-like; anthers introrse, two-celled; cells opening longitudinally.
- Pistil: Two to three carpels inserted in the bottom of the calyx tube and united into an inferior ovary. Styles two to three; stigmas capitate; ovules two in each cell.
- Fruit: Berry-like pome, globular, one-quarter of an inch across, bright red, borne in cymous clusters. Ripens in October and remains on the tree all winter. Flesh thin and sour, charged with malic acid; seeds light brown, oblong, compressed; cotyledons fleshy.[4]
[edit] Distribution
Native to northern North America; Eastern Canada:[5]
Canada - New Brunswick, Newfoundland, Nova Scotia, Ontario, Prince Edward Island, Quebec
Northeastern U.S.A.: United States - Connecticut, Indiana, Maine, Massachusetts, Michigan, New Hampshire, New York, Pennsylvania, Vermont, West Virginia
North-Central U.S.A.: United States - Illinois [n. (Ogle Co.)], Minnesota, Wisconsin
Southeastern U.S.A.: United States - Georgia, Maryland, North Carolina, Tennessee, Virginia
Sorbus americana is listed as endangered by the State of Illinois.[6]
[edit] Ecological aspects
The berries of American mountain-ash are eaten by numerous species of birds and small mammals, including ruffed grouse, ptarmigans, sharp-tailed grouse, blue grouse, American robins, other thrushes, waxwings, jays, squirrels, and rodents.
American mountain-ash is a preferred browse for moose and white-tailed deer. Moose will eat foliage, twigs, and bark. Up to 80 percent of American mountain-ash stems were browsed by moose in control plots adjacent to exclosures on Isle Royale. Fishers, martens, snowshoe hares, and ruffed grouse also browse American mountain-ash.
http://www.fs.fed.us/database/feis/plants/tree/sorame/all.html
[edit] Cultivation
Prefers a rich moist soil and the borders of swamps, but will flourish on rocky hillsides.
[edit] See also
- Rhus glabra (Smooth Sumac) - similar leaf pattern arrangement.
[edit] References
- ^ http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=25319&print_version=PRT&source=to_print ITIS Report Sorbus americana
- ^ a b McAllister, H.A. 2005. The genus Sorbus: Mountain Ash and other Rowans . Kew Publishing.
- ^ http://plants.usda.gov/java/charProfile?symbol=SOAM3 USDA Natural Resources Conservation Service
- ^ a b Keeler, Harriet L. (1900). Our Native Trees and How to Identify Them. New York: Charles Scriber's Sons. pp. 136–140.
- ^ http://www.ars-grin.gov/cgi-bin/npgs/html/taxon.pl?34994#uses USDA Germplasm Resources Information Network (GRIN)
- ^ http://plants.usda.gov/java/threat?statelist=states&stateSelect=17 USDA Natural Resources Conservation Services Threatened and Endangered Species (Illinois)
[edit] External links
- Sorbus americana - picture of young tree, and complete summary data
- Interactive Distribution Map for Sorbus americana
- distribution map
