Xerophyllum (plant genus)
| Xerophyllum | ||||||||||||
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Beargrass ( Xerophyllum tenax ) in Glacier National Park (United States) |
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| Systematics | ||||||||||||
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| Scientific name of the tribe | ||||||||||||
| Xerophylleae | ||||||||||||
| S. Watson | ||||||||||||
| Scientific name of the genus | ||||||||||||
| Xerophyllum | ||||||||||||
| Michx. |
Xerophyllum is the only genus of the tribe Xerophylleae in the family of melanthiaceae (Melanthiaceae). This genus consists of only two species . The two species differ mainly in the height of growth, the size of the leaves, the diameter of the inflorescences, with Xerophyllum tenax being slightly larger in all characteristics than Xerophyllum asphodeloides , and their area of distribution . The botanical genus name Xerophyllum is made up of the Greek words ξηρός xerós for "dry" and φύλλον phýllon for "leaf".
description
The two Xerophyllum species are perennial herbaceous plants . The roots are thick. They form woody rhizomes that end in tubers (with “tunics”). Upright and unbranched stems sprout from this , bloom only after a few years and die after seed formation. The foliage leaves, which are largely arranged in a spiral at the base, but also around the stem , are thin, linear and keeled. The leaf margin is sawn.
A terminal, racemose inflorescence is formed with closely spaced flowers and bracts . The small, fragrant flowers are hermaphroditic and threefold. The six more or less identical, cream-white bracts (tepals) have five to seven nerves. There are two circles with three stamens each; they are 3 to 4 mm long. Three carpels have become a top permanent ovary grown. The three free styluses are bent back.
Globular to egg-shaped, loculicidal capsule fruits are formed that contain two to four seeds per fruit compartment. The greenish-brown seeds are triangular, 3 to 4 mm in size and wingless.
The chromosome number for Xerophyllum tenax is 2n = 30.
use
Both species serve as ornamental plants .
The fibers of the leaves of the bear grass were woven into clothing and decorative waterproof baskets by the indigenous peoples . The fleshy rhizomes were roasted for several days and then eaten. Plant parts were used in folk medicine.
Systematics and distribution
The genus Xerophyllum consists of only two species. They used to form their own family Xerophyllaceae Takht. Both species were previously included in the genus Helonias . One species is native to eastern North America , the other to western North America:
- Xerophyllum asphodeloides (L.) Nutt. : It has a disjoint area in the dry oak hickory forests of the southern Blue Ridge Mountains and the dry sandy soils of the Pine Barrens in New Jersey . The alkaloid Xerophia was only detectedin this species(W. Procter 1839).
- Beargrass ( Xerophyllum tenax ( Pursh ) Nutt. ): Its range is mainly in western North America , from Canadian British Columbia in the north to southern California and in the east to Wyoming . Bear grass inhabits open coniferous forests , dry slopes, scree soils and clearings at altitudes between 0 and 2300 meters.
swell
- Frederick H. Utech: Xerophyllum in the Flora of North America, Volume 26, P. 71: Online (Engl.)
Individual evidence
- ^ Xerophyllum tenax at Tropicos.org. In: IPCN Chromosome Reports . Missouri Botanical Garden, St. Louis
- ↑ Entry in Plants for a Future.
