Characteristics
The pacific yew is a small to medium-sized evergreen tree, growing 10–15 m tall and with a trunk up to 50 cm diameter, rarely more. In some instances, trees with heights in excess of 20 m occur in parks and other protected areas, quite often in gullies.
The tree is extremely slow growing, and old trees often rot from the inside creating hollow forms. This makes it difficult and sometimes impossible to make accurate rings counts to determine a specimen's true age. Often damaged by succession of the forest, it usually ends up in a squat, multiple leader form.
It has thin scaly brown bark, covering a thin layer of off-white sap wood with a darker heartwood that varies in color from brown to a magenta/purplish hue. The leaves are lanceolate, flat, dark green, 1–3 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 except on erect leading shoots where the spiral arrangement is more obvious.
The seed cones are complex, each cone containing a single seed 4–7 mm long partly surrounded by a modified scale which develops into a soft, bright red berry-like structure called an aril, 8–15 mm long and wide and open at the end. The arils are mature 6–9 months after pollination, and with the seed contained are eaten by thrushes and other birds, which disperse the hard seeds undamaged in their droppings; maturation of the arils is spread over 2–3 months, increasing the chances of successful seed dispersal. The male cones are globose, 3–6 mm diameter, and shed their pollen in early spring. It is mostly dioecious, but occasional individuals can be variably monoecious, or change sex with time.
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