Conium maculatum

Conium maculatum, the hemlock or poison hemlock, is a highly poisonous biennial herbaceous flowering plant in the carrot family Apiaceae, native to Europe and North Africa. A hardy plant capable of living in a variety of environments, hemlock is widely naturalized in locations outside its native range, such as parts of North and South America, Australia and West Asia to which it has been introduced. Conium maculatum is known by several common names. In addition to the British hemlock, the Australian carrot fern and the Irish devil's bread or devil's porridge, the following names are also used: poison parsley, spotted corobane, spotted hemlock, and poison hemlock. The dried stems are sometimes called kecksies or kex. The plant should not be confused with the coniferous tree Tsuga, also known by the common name hemlock, even though the two plants are quite different. Similarly, the plant should not be confused with Cicuta (commonly known as water hemlock). Conium comes from the Ancient Greek κώνειον – kṓneion: 'hemlock'. This may be related to konas (meaning to whirl), in reference to vertigo, one of the symptoms of ingesting the plant. Conium maculatum is an herbaceous biennial flowering plant that grows to 1.5–2.5 m (5–8 ft) tall, with a smooth, green, hollow stem, usually spotted or streaked with red or purple on the lower half of the stem. All parts of the plant are hairless (glabrous); the leaves are two- to four-pinnate, finely divided and lacy, overall triangular in shape, up to 50 cm (20 in) long and 40 cm (16 in) broad. Although it looks like a carrot plant, poison hemlock can be distinguished by the smooth texture and light green color it possesses. The poison hemlock's flower is small and white. The flowers are loosely clustered and each flower has five petals. It has been introduced and naturalised in many other areas, including Asia, North America, Australia and New Zealand. The plant is often found in poorly drained soil, particularly near streams, ditches and other watery surfaces. It also appears on roadsides, edges of cultivated fields and waste areas and is considered an invasive species in 12 U.S. states. Conium maculatum grows in damp areas, but also on drier rough grassland, roadsides and disturbed ground. It is used as a food plant by the larvae of some Lepidoptera species, including silver-ground carpet. The poison hemlock moth (Agonopterix alstroemeriana) feeds on the plant during its larval stage. A. alstroemeriana has been widely used as a biological control agent for C. maculatum. Poison hemlock flourishes in the spring, when most other forage is gone. All plant parts are poisonous, but once the plant is dried, the poison is greatly reduced, although not gone completely.