Laurel roses
| Laurel roses | ||||||||||||
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Narrow-leaved bay rose ( Kalmia angustifolia ) cultivar 'Rubra' |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Kalmia | ||||||||||||
| L. |
The laurel roses ( Kalmia ) form a genus of plants in the heather family (Ericaceae). They are mainly found in North America.
description
Vegetative characteristics
Kalmia species usually grow as shrubs , only Kalmia latifolia rarely as a tree . The branches are mostly upright, but the branched Kalmia procumbens forms mats. The bark of the branches is glabrous to downy or hairy with glands. Most of the species are evergreen, but Kalmia cuneata is deciduous. The alternate, opposite or in threes in whorls of the branches arranged leaves are divided into petiole and leaf blade. The simple leaf blade has a smooth leaf margin.
As ornamental plants in parks and gardens, laurel roses are usually only around 1 meter high in the temperate latitudes.
Generative characteristics
The flowers are sometimes solitary or usually two to 40 in lateral or terminal, racemose , doldy , spiked or bundled inflorescences . The hermaphroditic flowers are radial symmetry and five-fold with a double flower envelope (perianth). The rarely four, mostly five green to greenish, mostly durable sepals are fused. The five petals are almost completely cup-shaped to bell-shaped fused or free. There are usually two (with Kalmia procumbens only one) circles with five stamens each, they do not protrude above the corolla. The stamens are usually hairy at their base. The anthers are mostly purple in color. The mostly bald ovaries are rarely two to five chambered. The straight or curved stylus does not protrude beyond the corolla and ends in a capricious or rarely five-lobed stigma.
The mostly five-lobed capsule fruits are more or less spherical and contain about 100 to 150 seeds. The elongated, egg-shaped or obovate seeds are often winged or tailed with a net-like seed coat (testa).
The basic chromosome number is x = 12.
Toxins
Both main types contain acetylandromedol in their leaves , which causes irritation of the oral mucous membranes, allergic reactions , nausea, disorientation, sweating, and stomach and intestinal problems with diarrhea. In severe cases of poisoning, the heartbeat slows down and respiratory paralysis can lead to death. Names such as English “Lambkill” (“lamb murderer”) or German sheep-laurel rose indicate this toxic side effect of the shrub.
Systematics and distribution
Of the approximately ten species today, eight are native to North America. Two types occur in Eurasia . There is one species in Cuba . Kalmia species are usually found on mountain slopes and in mountain forests.
The genus Kalmia was first published in 1753 by Carl von Linné in Species Plantarum , 1, p. 391. With the botanical genus name Kalmia , Carl von Linné honored his pupil Peter Kalm (1715–1779), a Swedish botanist who was a plant collector in eastern North America and sent the first Kalmia copies to Carl von Linné. The genus Kalmia belongs to the tribe Phyllodoceae in the subfamily Ericoideae in the family Ericaceae . Synonyms for Kalmia L. are: Dendrium Desv. , Kalmiella Small , Leiophyllum (Pers.) R. Hedw . , Ledum L. sect. Leiophyllum Persoon and, more recently, Loiseleuria Desvaux .
The genus Kalmia today contains about nine species:
- Narrow-leaved bay rose ( Kalmia angustifolia L. , Syn .: Kalmia carolina Small , Kalmia intermedia Lange ): With two varieties in eastern North America; in Central Europe wild in places . It has lanceolate oval leaves similar to those of laurel and blooms from May to June with pink or purple flowers.
- Sand myrtle ( Kalmia buxifolia (PJBergius) Gift & Kron , Syn .: Ledum buxifolium Bergius , Dendrium hugeri Small , Leiophyllum buxifolium (Bergius) Elliott , L. hugeri (Small) K.Schumann , L. prostratum Loudon , L. serpyllifolium DC. ) : It is native to North America.
- Kalmia cuneata Michx. : It thrives at altitudes between 20 and 200 meters in North Carolina and South Carolina .
- Cuban bay rose ( Kalmia ericoides Wright ex Grisebach ): It thrives in savannahs and pine heaths only in western Cuba .
- Kalmia hirsuta Walter : It thrives at elevations between 0 and 100 meters in open sandy savannas, sandy hills and pine barrens in Alabama , Florida , Georgia and South Carolina .
- Broad-leaved bay rose or mountain laurel ( Kalmia latifolia L. ): It thrives in North America at altitudes between 0 and 1900 meters. It has white-pink flowers and can reach dimensions of three to nine meters. The mountain laurel is the state flower of the US states Connecticut and Pennsylvania . In the USA , mountain laurel is also called Ivybush, Calico Bush, Sheep Laurel, Lambkill, Clamoun, Spurwood, which means "spore wood" because the Indians used to make their spurs from it.
- Kalmia microphylla (Hook.) A.Heller (Syn .: Kalmia occidentalis Small ): With two varieties in northern and western North America.
- Chamois, chamois or chamois heather , also alpine azalea, alpine heather, deer heather or rock rose ( Kalmia procumbens (L.) Gift & Kron , syn .: Azalea procumbens L. , Chamaecistus procumbens (L.) Kuntze , Loiseleuria procumbens (L.) Desvaux ): It has a wide distribution in North America and Eurasia.
- Poleiblättrige Laurel Rose ( Kalmia polifolia Wangenh. , Syn .: Kalmia glauca Aiton ): It thrives at altitudes between 0 and 800 meters widespread in North America.
swell
literature
- Jaynes, Richard A., 1997: Kalmia, mountain laurel and related species, Timber Press, Portland, Oregon, USA
- Shunguo Liu, Keith E. Denford, John E. Ebinger, John G. Packer, Gordon C. Tucker: Kalmia in der Flora of North America , Volume 8, 2009, p. 480: Online. (Section systematics and description)
Individual evidence
- ↑ First publication scanned at biodiversitylibrary.org.
- ^ Kalmia in the Germplasm Resources Information Network (GRIN), USDA , ARS , National Genetic Resources Program. National Germplasm Resources Laboratory, Beltsville, Maryland.
