Taxus is a genus of yews, small coniferous trees or shrubs in the yew family Taxaceae. They are relatively slow-growing and can be very long-lived, and reach heights of 1–40 m, with trunk diameters of up to 4 m.[citation needed] They have reddish bark, lanceolate, flat, dark-green 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.