What is Yew?
{{Taxobox | image = TXbaccata.jpg | image_width = 240px | image_caption = ''Taxus baccata'' (European yew) shoot with <br>mature and immature cones | regnum = [[Plant]]ae | divisio = [[Pinophyta]] | classis = [[Pinophyta|Pinopsida]] | ordo = [[Pinales]] | familia = '''Taxaceae''' | genus = '''''Taxus''''' | genus_authority = [[Carolus Linnaeus|L.]] | subdivision_ranks = Species | subdivision = }} [[Image:Taxus baccata MHNT flowers male.jpg|thumb|250px|Male cones of ''Taxus baccata'']] A '''yew''' is a [[conifer]]ous [[tree]]. The name is mainly used for species of the genus '''''Taxus''''', and sometimes for other conifers in the [[Family (biology)|family]] '''Taxaceae'''. == Poison == All species of yew contain highly [[poison]]ous [[alkaloid]]s known as [[taxane]]s. All parts of the tree except the [[aril]]s (red 'fruits') contain the alkaloid. The arils are edible and sweet, but the seeds are dangerously poisonous. Unlike birds, the [[human]] stomach can break down the seed coat and release the taxanes into the body. It can have fatal results if yew 'berries' are eaten without removing the seeds first. The seeds and leaves will kill [[cattle]] and [[horse]]s, but [[deer]] can break down the poisons and will eat yew foliage freely. Deer browsing of yews is often so extensive that wild yew trees are restricted to cliffs and steep slopes the deer cannot get to. The foliage is also eaten by the [[larva]]e of some [[Lepidoptera]]n [[insect]]s including the [[willow beauty]] [[moth]]. == Description == Yews are slow growing and can be very long-lived, and reach heights of 1-40 m, with trunk diameters of up to 4 m. They have reddish [[bark]], [[spear]]-shaped flat, dark-green [[leaf|leaves]] 1-4 cm long and 2-3 mm broad, arranged spirally on the stem, but with the leaf bases twisted to align the leaves in two flat rows either side of the stem. The tree is [[Flowering plant sexuality|dioecious]]: the sexes are on separate trees. The [[conifer cone|seed cones]] are highly modified, each cone containing a sing