Pacific yew, Taxus brevifolia

There are some old folks among us, silently watching our busy ways.  Pacific yew trees are like that…they were here before here was here.

Yes, older than Shasta, older than the Siskiyous.  Yews have traveled around the world, but remain their old selves.  Pacific yew is a conifer, like the pines and firs, but has amazing ancient traits unlike its brothers and sisters.

From a distance yews look like knarly, redwood bonsais, graceful yet full of individual personality.  The similarity to redwood is a clue to yew’s origins.  They’re close relatives, but the venerable giant redwood cathedrals are just new kids on the block, with a cool modernity compared to yew.

Archaic yew traits are many.  First, there are separate boy trees and girl trees…unusual among gymnosperms, or conifers.  The males make small pollen catkins under the young branch bases in the Spring, and look very similar to the same structures on redwood, cypress and sequoia trees.  The females are really different.  They make single naked seeds scattered sparsely under the young foliage, instead of a woody cone full of seeds like most conifers.  Those seeds develop an orange-red fleshy cup that attracts birds.  It’s not a berry or a fruit, but you can’t tell the birds that.

Incidentally, the passage of the seed intact through a bird enhances the germination, softening theseedcoat.  Pretty good chance it will be deposited with some fertilizer too!  Most conifer seeds have wings to aid with wind dispersal, but the yews borrow the wings of birds, potentially increasing their ability to spread widely into appropriate habitats.  The ‘fruits’ are sweet, but the seed if crushed is toxic, so spit them out.  Yew foliage and bark are also considered poison, but I’m not convinced.  I’ve seen yews turned into wild topiary in deer overwintering areas, heavily grazed over many years.  And that ‘poison’ bark can actually save lives.

Pacific yew bark contains taxol, a complex plant alkaloid that can inhibit cell division in cancer cells, and has been effective in the treatment of a variety of soft cancer tumors.  It’s interesting to note that several tribes north of here inhaled the smoke from the bark to relieve lung problems, perhaps helping to limit tumors.

Not many years ago, people in the Pacific Northwest began collecting the bark to sell to drug companies.  The price was good, and the yews suffered.  Bark stripping killed the trees, with the biggest, oldest specimens having the thickest bark.  Even the Forest Service got worried, and began a program to inventory stands, sample for taxol, and to propagate and preserve representative stands in orchards for future use.  Fortunately, just before bark stripping caught on in the Klamath watershed, a process was developed where European yew (Taxus baccata), which has been cultivated for centuries, are grown in farm fields where their needles can be sustainably harvested. A compound in the needles is extracted and converted to taxol, providing today’s anti-cancer drug in adequate quantities.

Another archaic property that yews possess is the absence of hairs on their roots, limiting water and nutrient absorption.  This helps explain their ‘happy spots’…usually in the forest understory near water, where summer moisture stress is minimized.  Being a smaller, heavily-branched tree with thin bark, yews tend to be herded off the dry slopes by fire, finding refuge in riparian habitats.  That said, they grow from the river to the mountain tops.  Up on Preston Peak, I think the highest trees I’ve seen were ancient yews tucked in the boulder fields, with sweeping views from Shasta to the sea.

And how about that wood?  Yew is beautiful, with a purple/red heart and blonde sapwood…tough as nails with a very high specific gravity.  It has an amazing quality of great bending strength, rapidly returning to its original shape.  It has been the wood of choice for archery bows around the world wherever it was found. The Karuk, Yurok, and Hoopa all passed this knowledge on over generations.  William the Conqueror wouldn’t have conquered if his English archers had not employed yew longbows.  Yew wood smooths to a satiny, skin-like feel.  This gentle strength was used industrially for textile mill spindles and parts well into the 20th century.  Perfect for buttons too folks, so find a nice, maybe dead limb, say thanks, and get to work!

Dean Davis
Certified Arborist WE-8600A