The Pacific yew
On a hot August day in 1962 Arthur Barclay stood in Washington States
Gifford Pinchot National Forest staring at a small stand of scraggly conifer
trees. A Harvard-trained botanist, Barclay worked for the New Crops Research
Branch of the Agricultural Research Service, an arm of the USDA. In the
stand, at an elevation of 1,500 feet, Barclay spotted a twenty-five foot
tall Pacific yew tree, Taxus brevifolia, which he designated B-1645.1
Barclay and his three graduate student assistants collected two samples:
PR-4959, stem and fruit; and PR-4960, stem and bark.
Barclay collected T. brevifolia, an evergreen, apparently because
the strategy was to collect at random. Not much was known about the tree.
It belonged to the genus Taxus, the yew, one of five genera in
the Taxaceae family. The yew is native to the Americas, Europe, and Asia.
The Pacific yew, T. brevifolia, is a tree of medium height with
reddish bark and flat, slightly curved needles about an inch long. It
lives in the shade of giant conifers on the banks of streams, deep gorges,
and damp ravines. It has hard wood that is of limited use. It has few
natural pests because most of it is poisonous. And, significantly for
the future, the Pacific yew grows very slowly.
Humans have made use of the yew since the dawn of history. A spear point
made of yew found in England is thought to be 50,000 years old. In the
Alps, an unfinished six-foot yew bow was found alongside the mummified
remains of a man who died 5300 years ago. The ancient Egyptians made household
implements and weapons of yew. Homer described archers besieging the walls
of Troy with yew bows. Rome armed its legions with yew lances, pikes,
and bows. The Celts used yew for tools and weapons. The yew influenced
English history; Kings Harold, William II, and Richard Lion-Heart were
killed with yew bows.
Because it is poisonous and because it was long used to make weapons,
the yew has mythological associations with death. The Greeks believed
the yew sacred to Hecate, goddess of the underworld. The scientific name
for the yew, taxus, is eerily similar to the Greek word for bow
and poison, toxon and toxicon. The Romans also associated
the yew with death, using yew boughs in funeral ceremonies.
This mythology, which focused on the European yew, Taxus baccata,
undoubtedly contributed to the scientific interest in the tree. An alkaloid,
taxine, was isolated in 1856 and found responsible for the European yews
poisonous nature. But there had been little scientific interest in the
Pacific yew, T. brevifolia. That would change in the 1960s when
Arthur Barclays collections reached the Research Triangle Institute.
1 B-1645 because it was the 1645th plant sample collected