Lilium grayi
Lilium grayi - Illustration by Joseph Dalton Hooker in 1892
Lilium grayi is a plant of the genus Lilium (Lilium ) in the section Pseudolirium ( American Section ). In the United States, the species is known as the Gray's lily. It is named after Asa Gray, an American botanist, named.
- 2.1 dissemination
- 2.2 habitats
- 2.3 stocks
- 2.4 Protection
- 3.1 hybrids
- 4.1 systematics
Features
Lilium grayi is a perennial, herbaceous plant. It reaches heights of growth up to 130 centimeters. It germinates delayed - hypogeous. In the first two years after germination Lilium flowers not yet grayi; During this time the onion is built up. Usually it blooms for the first time in the third year. The DNA of the species is 2n = 24 chromosomes distributed.
Onion
The bulbs are swellings of unbranched rhizomatic structures that are 2.2 to 2.6 inches high and 3.8 to 5 centimeters long. The rhizome is doing more than twice longer than high. The bulbs are, as is typical for lilies, composed of numerous, yellowish - white scales, which consist of up to two segments. The longest shed 0.9 to 2.2 centimeters long. Between the actual onions are unsegmented Rhizomstränge. The roots are adventitious roots that arise directly from the stem axis in part.
Shortly after the expulsion of the shoot from the bulb are the leaves in the bud huddled together on the cross and give the bud a roundish shape. After outgrowth of the stem axis is straight and smooth. The leaf position is lively or in part in lively three to five whorls of three to twelve leaves. The leaves are horizontal or slightly curved upwards, they are towards the tip lobed and are thus slightly bent downward. The leaf shape is elliptical to lanceolate or schmalelliptisch. The leaves are about 1.5 to 3.6 inches wide and 4.1 to 12.7 inches long, they are up to five times longer than wide.
The leaf margins are not curled, the leaf blade is sharp at the top, at the distal leaves less sharp. The main arteries run along and parallel to each other ( Parallelnervatur ). Abaxial, so the back edge of the sheet, and especially for the shoot axis towards the epidermis on the leaf veins is noticeably rougher. The leaf surface is covered here with tiny edged Trichomnadeln.
Flowers and Fruit
The plant blooms from late June to mid-July with one to nine, in culture also about twenty, nodding, stalked flowers in a large panicle. The flower stems are 2.6 to 6.5 inches long. The perianth is bell-shaped and does not smell. The flowers are hermaphroditic and threes, the six bracts ( tepals ) are alike. They are only slightly bent, at least the basal two-thirds of Hüllblattlänge 're at it, only after the bend begins. The color of the flowers varies from yellow- orange proximally ( at the base ) to dark red distally ( at the flowering tops ), they are densely covered with dark red speckles. The tepals are 3.1 to 5.6 inches long and 1.2 to 2 inches wide.
Each flower bears six stamens. The stamens (filaments ) are red. They run almost parallel to the pen of three fused carpels and are easily bent between 3 ° and 9 ° max out. The anthers ( anthers ) are magenta and between 4 mm and 1.2 inches long. The pollen russet. The stamp is from 2.4 to 3.8 inches long, the ovary is upper constant. The scar is 0.8 to 1.7 inches tall.
After blossoming, 2.1 to 3.7 centimeters are long and 1.5 to 2.1 centimeters wide capsule fruits. They are 1.5 to 2.1 times longer than wide.
Distribution, habitats, resources and protection
Dissemination
Lilium grayi is endemic to a very small area. Uncompounded, that is not hybridized populations of the species are found only in the Roan Mountain massif in North Carolina and Tennessee, where the species was discovered in 1840. The natural hybrid Lilium × pseudograyi is also found in small populations in the higher elevations of the Blue Ridge Mountains, including the Grandfather Mountain in North Carolina and Mount Rogers and Whitetop Mountain in Virginia.
The stock has declined drastically. In North Carolina, there were in 2000 only 61 stocks, but some of which consist of only five to ten individual plants. In Tennessee, there is only a single county small stocks.
Habitats
Lilium grayi need a very moist soil and prefers to grow in swamps or forest meadows. It requires an acidic soil, like on sandstone base. The preferred natural location is full sun and not shaded.
It occurs in forests, mainly from the American Red Spruce ( Picea rubens ) and Fraser fir (Abies fraseri ) are dominated, and is found at altitudes from 1200 to 1900 meters. The hybrid Lilium × pseudograyi is also found on altitudes up to 900 meters.
The greatest threat to the stocks goes from fungal diseases, similar to anthracnose from. Fungi of the genera Colletotrichum, Botrytis and Alternaria attack the lily. This attack by Botrytis or Alternaria but always seems to precede a Colletotrichum infection.
Another danger is the increased grazing of pastures by cattle and the increase of rabbits and wild boars in the region. As with many other endangered species is also in Lilium the destruction of habitats by humans and illegal collecting plants for the population decline grayi responsible.
Protection
The species is on the list of candidates for the Endangered Species list of the United States Fish and Wildlife Service. In the State of Tennessee the species is since 1986 as acutely threatened with extinction (S1 ) performed in Virginia, the stocks are since 1991 as critical ( S2) To the way you can at least ex receive situ, it was proposed to collect from all natural stocks seeds and to preserve it.
Ecology
Lilium grayi is highly specialized with respect to their pollination. Due to their special flower shape they can be pollinated only by hummingbirds ( Archilochus colubris ). Only some Nymphalidae ( Nymphalida ) of the genus Speyeria are still able to receive the nectar of the flowers, while the plants are pollinated but not reliable.
The similarity of the flower morphology to Lilium Lilium maritimum bolanderi and the American West is remarkable. Since this morphology was acquired independently, this suggests a high selection pressure in the pollination by hummingbirds ( Trochilidae ) for these species.
Hybrids
Lilium grayi is closely related to the Canada lily, with which it sometimes forms hybrids in nature, William Bywater Grove described this as hybrids Lilium × pseudograyi. Habitus also corresponds to a mixture of the two parents in most measurements in the range between species.
In horticulture, the species has been rarely used for breeding. In gardens it is to find a rarity outside of the United States as well as not.
Botanical history
Lilium grayi was discovered in 1840 by Asa Gray, but not until 1879, first described by Sereno Watson, who named it after Gray. 1888, she was first cultivated by Harlan Kelsey. 1934 was Lilium grayi attention when she won the Award of Merit of the British Royal Horticultural Society.
System
Comber put the type in 1949 in his classic, though now outdated system with Lilium canadense, L. iridollae, L. michiganense, L. michauxii, L. superbum and L. pyrophilum in a subsection. With the Canada lily ( L. canadense ) they can hybridize, which can be interpreted as an indication of a very close relationship. In molecular genetic studies Lilium grayi was not previously considered.