Cicuta virosa

Water hemlock ( Cicuta virosa )

The persistent and highly toxic water hemlock or tyrant ( Cicuta virosa ) is a flowering plant in the carrot family ( Apiaceae ) and next to the spotted hemlock ( Conium maculatum ) and the Fool's Parsley ( Aethusa cynapium ) one of the most poisonous umbelliferous. The plant is to be perceived by some people as offensive.

Occurrence

The water hemlock is found in moist areas silting meso-to eutrophic ( mesotrophic = moderate nutrient content, eutrophic = high nutrient content) of stagnant water such as lakes, ponds or ditches. Other stocks may occur in wet alder forests. At present, its holdings, however, strongly retreating, which is mainly due to the increasing use of intensive silting areas. In most provinces, the water hemlock is now classified in the Red List of vascular plants as endangered or critically endangered. But he is seriously threatened, partly in its holdings in the rest of Europe. The water hemlock occurs only in Eurasia course in submeridionalen to boreal climates from the flat until the hill country. He is the Kennart the plant association Cicuto - Caricetum pseudocyperi and has its main occurrence in association glutinosae Alnion ( alder swamps ).

Identifying

The water hemlock can be up to 1.50 m tall and has a bulbous thickened Rhizomknolle that is hollow and chambered by transverse walls appear. Such air chambers serve as an adaptation to the low oxygen, muddy ground. Its cells have 11 or 22 chromosomes. It forms two and three times pinnate leaves whose Fiederabschnitte are linear lanceolate and sharply cut. The individual flowers are available in a 10 - to 20 - rayed compound umbel. The bracts of the umbel are missing. The individual umbellules are floriferous and have numerous Hüllchenblätter on. The fruits are only about 2 mm wide, almost spherical shaped and ribbed characteristic.

Ecology

The water hemlock is a perennial plant stem or a swamp or rooted aquatic plant. The tubed stems and tuberous thickened, stunted shoot base have air chambers in the internodes; This is an adaptation to the oxygen-poor ground. Through the air chambers and the tubers are buoyant.

The flowers are vormännlichen " nectar leading disk flowers ". Pollinators are mainly Diptera, especially hoverflies. Blooms from July to September.

The fruits are Doppelachänen with swimming fabric for the floating spread. The fruits are light and cold to germinate.

Vegetative propagation is done by uprooted and floating tubers. The summer green water hemlock survived the winter in the protective layer of leaves of the soil.

Toxicity

All plant parts of water hemlock is highly poisonous, particularly the buoyant by air chambers tubers. The toxicity is caused by polyynes, in particular the Cicutoxin. After consumption of even small amounts can cause death due to respiratory paralysis. According to an old Prussian law, the plant should be exterminated because of their toxicity.