From Wikipedia, the free encyclopedia.
(This article is about plants named "hemlock." There is also a place in Michigan by that name: see Hemlock, Michigan.)
Several plants are called hemlock.
- Poison hemlock is a common European plant, Conium maculatum, of the Parsley family, Apiaceae (formerly Umbelliferae); it is toxic, containing the alkaloid Coniine.
- Water hemlock is Cicuta virosa, another deadly plant in the same family.
Similar in appearance to hemlock is Queen Anne's Lace, with the exception that the latter features purpleish flowers in the center. Likewise, parsnip, of the carrot family, which is plucked, cut up, and boiled into soups and other dishes, has a white cluster of flowers and grows in similar places. Parsnip can be easily mistaken as hemlock and vice-versa. A good rule of thumb is that hemlock is more stalk-like. It is essential, of course, that one knows what one is picking, or the results could very well be deadly.
Hemlock, Queen Anne's Lace, and Parsnip commonly grow in ditches in most temperate regions of the globe.
Quite different from these are the coniferous trees in the genus Tsuga, family Pinaceae. These are not toxic, being called 'hemlock' through a supposed similarity in the scent of the foliage to that of Conium.
- Western hemlock, Tsuga heterophylla. This is particularly common in the Pacific Northwest of North America and planted as a timber tree in Britain and some other temperate areas.
- Eastern hemlock Tsuga canadensis.
- Mountain hemlock Tsuga martensiana.

