Biology:Ornithogalum umbellatum

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Short description: Species of spring flowering bulb in family Asparagaceae

Ornithogalum umbellatum
Ornithogalum umbellatum flowers, open and closed
Scientific classification edit
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Monocots
Order: Asparagales
Family: Asparagaceae
Subfamily: Scilloideae
Tribe: Ornithogaleae
Genus: Ornithogalum
Species:
O. umbellatum
Binomial name
Ornithogalum umbellatum
Map-World-Ornithogalum-umbellatum.png
Global distribution (native + introduced) of Ornithogalum umbellatum
Synonyms[1]
P3+3 A3+3 G(3)
Floral formula: Flowers actinomorphic and hermaphrodite with 6 undifferentiated tepals in two whorls of three, the same number and arrangement of stamens, and a superior ovary with 3 fused carpels
From centre outwards: Trilocular ovary, 6 stamens, 6 tepals

Ornithogalum umbellatum, the garden star-of-Bethlehem, grass lily, nap-at-noon, or eleven-o'clock lady, a species of the genus Ornithogalum, is a perennial bulbous flowering plant in the asparagus family (Asparagaceae). O. umbellatum is a relatively short plant, occurring in tufts of basal linear leaves, producing conspicuous white flowers, in a stellate pattern, in mid to late spring. The flowers open late in the day (hence some of its common names), but when closed have a green stripe on the outside. It is native throughout most of southern and central Europe, and north-western Africa. O. umbellatum is often grown as a garden ornamental, but in North America and other areas it has escaped cultivation and can be found in many areas, where it may become an invasive noxious weed. Parts of the plant are considered poisonous, but are used in some regional cuisines. Essences are also sold as patent remedies. O. umbellatum has been depicted in art by artists such as Leonardo da Vinci, and folklore has suggested it originally grew from fragments of the star of Bethlehem, hence its horticultural name.

Description

O. umbellatum is a perennial herbaceous bulbous plant (geophyte), dying back after flowering, to an underground storage bulb. The following year, it regrows from the often shallow rooted bulbs, which are ovoid with a membranous coat,[2] 15–25 millimetres (12–1 inch) long and 18–32 mm (341 14 in) in diameter. The bulbs form multiple leaf-bearing bulbils that soon separate but remain close by.[3] Initially the plant forms 6–10 basal leaves, that arise in tufts from the bulbs. The leaves are grooved (canaliculate), smooth (glabrous) and linear with a white to light green linear midrib on the upper surface, and grow up to 30 centimetres (12 in) long and 8 mm (14 in) broad.[4]

O. umbellatum is scapose, with a glabrous flower stem (scape) that emerges from the leaf tufts later and is about 10–30 cm (4–12 in) in height, tapering at its tip.[2]

Plant Morphology
Bulb with associated bulbil
Bulb with bulbil
Entire plant after digging up
Ornithogalum plant
Scapes arising from tuft of leaves
Clump of scapes with closed flowers arising from basal leaves

The inflorescence bears 6–20 flat star shaped flowers on ascending stems (pedicels), 3–3.5 cm (1 141 12 in), associated with membranaceous leaflets (bracts), 2.5–3 cm (1–1 14 in), in an open branching umbrella (umbel) shaped terminal cluster, described as a corymbose raceme.[3] The petal-like perianth is radially symmetric (actinomorphic), which is 1.5–2 cm (1234 in) in diameter, consists of six lanceolate tepals which are white with a green stripe on the underside (outside), 15 mm (12 in) in length and 5 mm (14 in) wide. From the outside the closed flower appears green with white margins.[2]

The reproductive parts consist of both male (androecium) and female (gynoecium) parts (hermaphrodite). The androecium has six yellow-brown stamens that are free of the perianth and form two groups, each of about 5–8 mm (1438 in), with filaments that are simple and flattened and oblong anthers that are 2–4 mm (116316 in). The gynoecium has a single pistil with a superior (i. e. above the floral parts) ovary that is ovoid to obovoid, 3–4 mm (18316 in), and longer than the style that extends above it. The fruit is a capsule which is oblong-ovoid with 3 sides and 6 ribs. Within it, each locule contains many seeds with a black coat of phytomelan.[5][6] The species is polyploid (having more than two sets of chromosomes).[7]

Floral morphology
Arrangement of floers in inflorescence
Inflorescence, pedicels & bracts
Underside of tepals
Underside of tepals
Flower seen from above, close up
Detail of flower from above
Side view of flower
Flower from side
Lateral view of reproductive organs
Detail of structures
Capsules on scapes, following pollination
Capsules on scapes

Taxonomy

John Gerard's illustration
Illustration by John Gerard
1597
page from Linnaeus' Species Plantarum, describing Ornithogalum umbellatum
Description by Linnaeus
1753

Ornithogalum umbellatum has been known and described for a long time, according to some authors, as far back as Dioscorides in the first century.[8][9][10] In 16th-century England, William Turner (1562) mentions it.[11] In Henry Lyte's 1586 New Herbal (a translation into English of Dodoens' 1554 Cruydeboeck), reference is made to an Ornithogalum as the White Field Onion. John Gerard, in his Herball of 1597, describes Ornithogalum as the "star of Bethlem".[12] The species known today as Ornithogalum umbellatum was first formally described by Linnaeus (1753),[13] who is the botanical authority for the species (L.). O. umbellatum is the type species of the genus Ornithogalum, which contains about 50 species.[14] The lectotype (reference specimen) was established by Stearn in 1983.[15]

Etymology

The species epithet reflects the flower formation as an umbel.[16] The plant's many common names include garden star-of-Bethlehem,[17] sleepydick,[18] nap-at-noon,[7] grass lily, summer snowflake, snowdrop, starflower, bird's milk, chinkerichee, ten-o'clock lady, eleven-o'clock lady, Bath asparagus, and star of Hungary. The references to the time of day reflect the opening times of the flowers, opening late and closing at night or in cloudy conditions. The star names indicate the arrangement of the petals and bird's milk is a literal translation of ornithogalum.[19][20][21] It has also been called dove's dung, equating it with a plant described in the bible.[22] [23] The name star-of-Bethlehem is shared by a number of species of Ornithogalum, due to the white stellate flowers, and the folklore relating the flower to the biblical star-of-Bethlehem (see In popular culture).[24]

Distribution and habitat

A native of most of Europe,[25] North Africa and western Asia, O. umbellatum has been adopted as an ornamental garden plant from where it has escaped and naturalised widely in North America,[7] where it is considered an aggressive noxious weed of lawns, gardens and no-till agricultural land, which can be difficult to eradicate.[23] In Europe its range extends from Ireland[26] and Portugal in the west, Italy in the south, north to parts of France and east to Turkey[2][16][18] and the Levant.[27]

O. umbellatum prefers damp habitats, being found along rivers, streams, and lower, wet areas of pastures.[23] It is tolerant to shade and soil type.[28]

Ecology

Life cycle

Ornithogalum umbellatum is thermoperiodic, requiring a cold winter to complete its life cycle.[29] It first appears in early spring as tufts of leaves, prior to flowering (proteranthous), which occurs in late spring (May–June), the leaves fading prior to blooming. It reproduces by its bulbs, which form many offsetting bulbils that can be dispersed by water.[2] Like many bulb plants from temperate regions, a period of exposure to cold is necessary before spring growth can begin. This protects the plant from growth during winter when intense cold may damage it. Warmer spring temperatures then initiate growth from the bulb. O. umbellatum spreads aggressively in clumps by means of these offsets.[16][30]

Pollination

The flowers are insect pollinated, but may also be self-fertile, forming seeds in summer (June–July).[28] Seed dispersal plays a relatively minor role in propagation, but accounts for isolated blooms.[29]

Effect of light

The petals exhibit photoperiodism, often opening at noon and closing at night or on cloudy days.[7]

Effect of light
Closed flowers on cloudy day
Cloudy day
Same plant on sunny day with open flowers
Sunny day

Cultivation

Leonardo da Vinci's Leda and the Swan, in which she holds a bouquet of Ornithogalum umbellatum in her hand
Leda with star of Bethlehem

Ornithogalum umbellatum requires considerable moisture during winter and spring, but can tolerate summer drought. It can be grown in a woodland garden as semi-shade is preferable. It is hardy to zone 5 UK,[28] 4–9 USDA, and can become invasive. It is produced commercially as an ornamental garden plant.[20] To control invasive tendencies, it is best to plant in a container or an edged area.[31] O. umbellatum may be grown as an indoor plant.[32]

Toxicity

The plant, especially the bulb and flowers, contains cardiac glycosides, specifically convallatoxin and convalloside which are toxic to humans and livestock.[2][6][7] Symptoms of poisoning include nausea, salivation, vomiting, diarrhea, and shortness of breath, as well as pain, burning, and swelling of lips, tongue, and throat. Prolonged contact may lead to skin irritation.[23][33]

Uses

Despite the known toxicities, the plant has been described as edible for 2,000 years[8][34] and incorporated into some traditional regional cuisines (e.g. Turkey)[35] and traditional medicine (e.g. India).[36] In Britain, the plant has long been the subject of herbals for its claimed culinary and medicinal properties.[12][10] This includes drying and grinding the bulbs, or boiling them and baking the flowers into bread.[30][37] Essences are sold as patent remedies and for aromatherapy,[30] such as Bach flower remedies.[38][39] Medical authorities advise against ingesting any part of the plant.[40]

In culture

Drawing of flowers by Da Vinci
Leonardo da Vinci drawing of flowers

Leonardo da Vinci drew O. umbellatum and included the plant in one of his depictions of Leda and the Swan (1508–1515), in which the flowers are held in Leda's left hand.[41][42] In folklore, the biblical star of Bethlehem is said to have fallen to the earth and shattered into pieces which became the ubiquitous white flowers.[24] Legend has also associated it with the journeys of Crusaders and pilgrims to the Holy Land.[37]

A biblical passage in 2 Kings 6:25 relates an account of a siege in Samaria in which the desperate population consumed the excrement of doves (chiriyonim). "There was a great famine in Samaria; and behold, they besieged it, until a donkey's head was sold for eighty shekels of silver, and a fourth of a kab of dove's dung for five shekels of silver". There has been considerable discussion as to the exact meaning of this term. In notes taken by Paul Dietrich Giseke from a lecture by Linnaeus[34] it is suggested that this Stercus Columbarum was in fact the plant Ornithogalum umbellatum, which grew abundantly in Palestine and "unde Anglis Bethlem's Star dicitur" (is known to the English as Bethlem's Star), the white colour of which resembled the excrement of birds, hence the name lac Avium (bird milk or Ornithogalum), and which was still eaten by the poor of that country.[43][44]

Culturally, the flower has been associated with purity and hope, atonement and reconciliation.[30]

Grass lilies make a number of appearances in the Metal Gear video game series.

References

Bibliography

Books

Historical sources

Articles

Databases

Other websites

External links

Wikidata ☰ Q161155 entry