In other languages, Taxus is commonly known as Eibe in the German language. The oldest recognizable yew is the Triassic species, Paleotaxus rediviva , found in strata million years old.
The mid-Jurassic species Taxus jurassica million years old is more recognizable as a member of Taxus , containing features characteristic of T. A Quaternary yew, Taxus grandis , is probably simply T. Yews are relatively slow-growing and can be very long-lived, reaching mature heights of 3 to feet 1 — 40 m , with trunk diameters of up to 12 feet 4 m , measured at breast height.
The most distinct yew species are the Sumatran yew T. The Mexican yew T. The Florida yew, Mexican yew and Pacific yew are all rare species listed as threatened or endangered. All species of yew contain highly poisonous alkaloids known as taxanes, with some variation in the exact formula of the alkaloid between the species.
All parts of the tree except the arils contain the alkaloid. The arils are edible and sweet, but the seed is dangerously poisonous; unlike birds, the human stomach can break down the seed coat and release the taxanes into the body.
This can have fatal results if yew 'berries' are eaten without removing the seeds first. Grazing animals, particularly cattle and horses, are also sometimes found dead near yew trees after eating the leaves, though deer are able to break down the poisons and will eat yew foliage freely. In the wild, deer browsing of yews is often so extensive that wild yew trees are commonly restricted to cliffs and other steep slopes inaccessible to deer.
Yew wood is reddish brown with whiter sapwood , and is very springy. It was traditionally used to make bows, especially the longbow. Most longbow wood used in northern Europe was imported from Iberia, where climatic conditions are better for growing the knot-free yew wood required. The yew longbow was the critical weapon used by the English in the defeat of the French cavalry at the Battle of Agincourt, It is suggested that English parishes were required to grow yews and, because of the trees' toxic properties, they were grown in the only commonly enclosed area of a village — the churchyard.
The yew tree can often be found in church graveyards and is symbolic of sadness. Yews are widely used in landscaping and ornamental horticulture. Over cultivars of yews have been named, the vast majority of these being derived from Taxus baccata European yew or Taxus cuspidata Japanese yew. The hybrid between these two species is Foundation yew Taxus x media.
A popular fastigiate selection of the European yew Taxus baccata 'Fastigiata' is often called the Irish yew, which often exacerbates the difficulties with common names. A few cultivars with yellow leaves that are being propagated, collectively are known as golden yews, which is another nomenclature blunder.
The Pacific yew Taxus brevifolia , native to the Pacific Northwest of North America, and Canada yew Taxus canadensis are the sources of paclitaxel or Taxol, a chemotherapeutic drug used in breast and lung cancer treatment and, more recently, in the production of the Taxus drug eluting stent by Boston Scientific. Over-harvesting of the Pacific yew for this drug led to fears that it would become an endangered species. However, methods were developed to produce the drug semi-synthetically from cultivated yews, without the need to further endanger the wild populations, and the Pacific yew is not endangered.
Other yew species contain similar compounds with similar biochemical activity. Docetaxel, an analogue of paclitaxel, is derived from the Taxus baccata. Shopping Bag. Over 50 in stock Taxus PDF. Add to Wish List. Valley Yarns Taxus is a fun must-have unisex pullover combining texture and stranded colorwork knit in Northfield.
This crewneck sweater has a simple texture pattern on the lower body and a fun colorwork pattern on the upper sleeves and lower chest. Valley Yarns Northfield is a glorious blend of Merino, baby alpaca, and silk. This DK weight is perfect for warm, cozy pieces that you want to be next-to-the-skin soft.
The Wave Rib stitch pattern is charted and written out, and the colorwork pattern is in chart form only. This pattern is only available as a PDF download! Click here to purchase this pattern as part of a project kit. Product Details Valley Yarns Taxus is a fun must-have unisex pullover combining texture and stranded colorwork knit in Northfield.
Attributes Author Julie Turjoman. Getting your download. Digital product.
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