Pacific yew Facts for Kids

The Pacific Yew is a unique tree that grows in the Pacific Northwest of North America. You can find it from Alaska all the way down to central California. It usually grows near the coast, but some can also be found inland in places like British Columbia and Idaho. This tree is part of the yew family, known as Taxaceae.

What the Pacific Yew Looks Like
- Pacific Yew Reproduction and Seeds
Where the Pacific Yew Lives
Different Kinds of Pacific Yew
How People Use the Pacific Yew
- Discovery of Taxol Medicine
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What the Pacific Yew Looks Like

The Pacific yew is a small to medium-sized evergreen tree. This means it keeps its green leaves all year long. It is also a conifer, which means it grows cones instead of flowers.

This tree usually grows about 10 to 15 meters (33–49 feet) tall. Its trunk can be up to 50 centimeters (20 inches) wide. In special, protected places, some trees can grow even taller than 20 meters (66 feet).

The Pacific yew grows very slowly. Its trunk often rots from the inside, becoming hollow. This makes it hard to figure out how old a tree is by counting its growth rings.

The bark of the tree is thin and scaly, with a brown color. The wood underneath can be off-white on the outside and darker inside. The center wood, called heartwood, can be brown, purplish, or deep red.

Its leaves are flat and dark green. They are about 1 to 3 centimeters (0.4–1.2 inches) long. The leaves grow in a spiral pattern on the stem. However, they often twist to look like they are in two neat rows on each side of the stem.

Pacific Yew Reproduction and Seeds

The Pacific yew has special seed cones. Each cone holds one seed, which is about 4 to 7 millimeters (0.16–0.28 inches) long. This seed is partly covered by a soft, bright red, berry-like part called an aril. The aril is about 8 to 15 millimeters (0.31–0.59 inches) long and open at the end.

The arils become ripe 6 to 9 months after the tree is pollinated. Birds like thrushes enjoy eating these red arils. When they do, they spread the hard seeds in their droppings. This helps new yew trees grow in different places.

Male cones are round, about 3 to 6 millimeters (0.12–0.24 inches) wide. They release their pollen in early spring. Most Pacific yew trees are dioecious. This means a single tree usually has either male cones or female cones, but not both. Sometimes, a tree might have both, or even change its sex over time.

Where the Pacific Yew Lives

Pacific yew trees can grow in many different environments. In dry areas, they often grow close to streams. In moist areas, they can be found on slopes and even on top of ridges.

This tree can grow well in the shade, but it can also grow in sunny spots. Because it likes shade, it often grows under taller trees. This helps it provide shade to streams, keeping the water cool for animals.

Different Kinds of Pacific Yew

While the Pacific yew is usually a tree, there are also forms that look more like shrubs. One of these is called Taxus brevifolia var. reptaneta. This type often creeps along the ground before growing upwards. Its branches tend to grow on one side of the stem.

This shrub form is sometimes called "thicket yew." This is because it can root as it creeps, forming thick groups of yew plants. Unlike the typical tree, thicket yew can grow in open, sunny areas, like paths cleared by avalanches. It can also grow in the shade of the forest.

Another type is Taxus brevifolia var. polychaeta. Most yew trees have a single seed on a small shoot. But this variety has a longer main shoot with up to five smaller shoots. This makes it look a bit like a worm, so it's sometimes called 'worm cone yew'. This variety seems to be quite rare.

How People Use the Pacific Yew

Native American tribes traditionally used the wood of the Pacific yew. They made bows, paddles for canoes, and many other everyday items. The wood is also used in Japanese carpentry for decoration.

Many parts of yew trees are poisonous and can be dangerous if eaten. However, the soft red aril around the seed is usually safe to eat. This is true as long as the seed inside is not chewed or swallowed. Birds eat these arils and help spread the seeds.

Discovery of Taxol Medicine

A very important medicine called paclitaxel (also known as taxol) can come from the Pacific yew. This medicine is used in chemotherapy to treat different types of cancer, such as breast, ovarian, and lung cancer.

When scientists found out how useful taxol was, the Pacific yew was already becoming rare. So, it wasn't harvested much from its natural home. Instead, scientists found a way to make a similar medicine from other types of yew trees that are grown on farms. This made sure there was enough medicine for everyone who needed it.