Ornithogalum umbellatum

Umbels milk Star ( Ornithogalum umbellatum )

As umbels milk star, Doldiger Star of Bethlehem Star of Bethlehem or a species aggregate ( Ornithogalum umbellatum - aggregate) from the kind of milk Star ( Ornithogalum ) within the family of asparagus plants ( Asparagaceae ) is called. The division of the Ornithogalum umbellatum aggregate into different species or sub- species is the subject of current botanical research. Ornithogalum umbellatum aggregate to include the species Ornithogalum angustifolium, Ornithogalum tenuifolium, gussonii Ornithogalum, Ornithogalum Ornithogalum orthophyllum and kochii and many more. These species can only be distinguished by cytological examinations sure, since the determination of characteristics usually not unique and the individual species are partly not yet described in detail.

Description

The distinction of the different subspecies of Ornithogalum umbellatum aggregate alone on external characteristics is very difficult, since they only differ slightly.

Vegetative characteristics

These types of Ornithogalum umbellatum the aggregate grow as a perennial herbaceous plant and reaches stature heights between 10 and 30 cm. This form Geophyten onions as outlasting that are surrounded by many bulblets. The spring appears, usually four to six (rarely up to nine) basal leaves are 2-6 mm wide, parallel-veined simply have a white center stripe. While the leaves are usually highly colored green before flowering time and stand upright, they will bloom longer and softer so that they begin to hang down. After the flowering period the leaves turn yellow and soon die.

Generative features

The short, doldentraubige inflorescence contains eight to twenty flowers. The hermaphrodite, radial symmetry blooms are triple. The six arranged bloom ( tepals ) are white, greenish or under hand with green stripe means, are 15 to 22 mm (rarely to 30 mm) and 4 to 8 mm wide. There are two circuits, each provided with three stamens of which have a length, the outer 5-7 mm, and the inner length 6 to 8 mm. The simple up to 3 mm wide stamens are winged. Three carpels are fused to a 5 to 6 mm long, distinctly six -winged ovary. The stylus is 3 to 4 mm long. The flowering period extends from April to June.

The lower fruit stalks are last protruding horizontally. The dreifächerige, winged, fleshy fruit capsule is truncated and contains many seeds.

Ecology

The umbels Milk star is a bulbous Geophyt; his bulbs are 2.4 m deep. The spring leaves drag an early and are no longer visible in the summer. The basal leaves are fleshy - rinnig and so direct the water to the roots.

The flowers are vorweibliche, opened in the sunshine " nectar leading disk flowers "; with us, they are often sterile. The nectar is at the edge of the carpels deposited ( Septalnektarien ) and runs down on the outer grooves. From the anthers to first open the 3 outer, then the inner 3. Besides hermaphrodite plants are also those before with not opening anthers; the plant is so gynodiözisch. The flowers are pollinated by insects or there is self-pollination, for example, when the flowers close in dull weather or afternoon, or when moving the dust bag before pollination to scar down.

The fruits are subject to gravity spreading. The seeds have an oil body and are spread by ants ( myrmecochory ). In Central Europe, but often is no seed set.

Vegetative propagation is done by the small, sparsely -scale bulbils, for example, are abducted by voles, but also by the people with arable soil.

Toxicity

Especially toxic are the onions; they contain cardenolides Convallatoxin (0.04 %) and Convallosid which are particularly strong on the heart. The biological activity is in the onions to the heyday of the highest.

Occurrence

In Austria it is scattered to rare in all states except Vorarlberg ( extinct).

In Switzerland, he is in the Central Plateau, the Jura and the southern Ticino before, in the northern Alps, the Valais and Grisons he is rare.

In North America, he is a neophyte.

As the site preferably, the umbels - Milchstern roadsides, vineyards and dry to fresh pastures. It grows like on clay soils. It is relatively rare, but it is there, where it grows, usually heaped before.