True yew wood is harvested from trees of the genus Taxus. In the United States, wood sold as yew is Pacific yew or Western yew, from the species Taxus brevifolia. Yews are coniferous trees, related to pines and other softwoods. Botanists classify another species sold under the trade name "New Zealand yew" in a different family from true yew. Yew trees are generally small and irregularly shaped, which makes lumber cut from the trees scarce and relatively expensive.
The heartwood of the yew tree covers a wide range of colours including shades of brown, orange and gold, often with purple streaks. The wood is characterised by a high lustre. Yew sapwood is considerably lighter, in shades of white and yellow, and clearly differentiated from the heartwood. Perhaps because yew trees are not often tall and straight, the wood grain is unpredictable and can be straight, interlocking, closed or figured.
Dry yew wood has a density of 15kg. per cubic foot, similar to that of most pines. Although considered a softwood because it is a conifer, yew's wood is hard and resilient. When tested using the industry standard Janka hardness test, Pacific yew receives a hardness rating of 1600, a ranking similar to that of oak or hickory. The wood has above-average resistance to natural decay, and is considered suitable for exterior use without additional treatment.
Although the wood of the Pacific yew has unpredictable grain, it remains suitable for carving and turning. The wood is especially well-suited for bending, so historically has been used in applications such as chair backs that require this property. Drilling, screwing and nailing are all average or better.
Because large pieces of yew lumber are rare, most of this wood in the United States finds its way into small carved or turned objects, where its striking colours and irregular grain are well-displayed in plates, bowls and small decorative wooden items. Yew is also found in furniture, bows, paddles for kayaks or canoes, some fine cabinetry, and musical instruments.
Because of its strength and flexibility, yew wood, particularly from a related species, the European yew, was historically used to make long bows. Special processing of the bark of the Pacific yew yields the anti-cancer drug Taxol, which takes its name from the genus name of the yew. Taxol and other drugs (generic name paclitaxel) derived from the bark of the yew are used to treat several different cancers.