By Terry Twigg
(January 6, 2024) — New Year. The winter solstice is just behind us, and as people have done since the beginning of time, we struggle to remind ourselves that, however long and dark the nights may be, they are slowly, steadily ceding precious minutes to daylight as the world tilts back toward the sun. We are never more aware of the passage of time, the eternally changing seasons, our past losses and hopes for the future, than at the new year. Light from darkness; life from death.
Nothing in our gardens better captures this duality than the yew tree. From the beginning of human history, or even earlier, people cut evergreen branches of yew to brighten winter’s darkness. For thousands of years, across tribes and religions, it was venerated simultaneously as a sacred symbol of immortality and as an agent of death. Immortal, because yews are among the longest-living trees; some of the oldest, particularly in the British Isles, are documented at more than a thousand years, while the fourteenth-century Irish Book of Lismore prophesies three lifetimes of the yew for the world from its beginning to its end. And an agent of death, because it’s one of the most toxic plants known.
Yew’s longevity is attributable in part to its growing habits. It regenerates readily from stumps and roots, making it ideal for topiary and forgiving of pruning mistakes. (If your house has overgrown yew foundation plantings, don’t yank them out. Cut them back hard, and they’ll respond with new, dense foliage.) It sends out downward-growing branches which root where they touch the ground, effectively cloning the tree, and then grow upward, merging with the original trunk and eventually replacing it as the oldest parts die out.
Little wonder the tree-worshipping Druids revered it as a sacred symbol of reincarnation. To them, it was one of five sacred trees brought from the Otherworld, possessed of magical properties, and therefore their priests’ preferred wood for staffs and wands. (Given my Irish and English heritage, and more pointedly, my name, it amuses me to believe I must be of Druidic descent.)
Old World yew trees resemble our East Coast native, Taxus Canadensis, in foliage and fruit, but there the similarity ends. The American native is an understory shrub, rarely more than six feet high. English yews can tower sixty or eighty feet, or even more, while Japanese yews, the variety most commonly found in American gardens, can reach 50 feet . But whether native or imported, yews in American landscaping are usually pruned into boring gumdrops. In the British Isles and northern Europe, they are often found as towering, wildly atmospheric features of churchyards and cemeteries. As the Christian belief in the resurrection supplanted the pagan doctrine of reincarnation, new churches were built on the ancient sacred sites—which explains why so many churchyard yews are believed to be much older than their churches. Yews were believed to have mystical powers to purify the dead or to keep their souls pinned in place. An alternate, more prosaic explanation is that their poison was an incentive for people to make sure their livestock didn’t wander into the churchyard.
How toxic? Enough to feature on numerous “Top Ten” lists; to have its fatal dose for an adult estimated as just 50 grams of needles or two seeds; to have “slips of yew, silvered in the moon’s eclipse” stirred into their cauldron by Shakespeare’s three witches in Macbeth. Its taxane alkaloids kill quickly, stopping your heart. Our native is less toxic than its European cousin, but not by much. You don’t need to ingest it to be affected: the toxins can be absorbed by the skin, or breathed in if the branches are burned (don’t). According to legend, sleeping under yew causes hallucinations, and apparently there’s some evidence that, in certain conditions, the plant does emit toxins in gaseous form.
As with many plants, the poison is most concentrated in the seed. Unfortunately, yew seeds are wrapped in fleshy red berries (more accurately, “arils”), tempting to animals and small children. The red flesh is the only part of the tree free of poison. Birds and some mammals are able to safely eat the seed, because it passes out of their bodies undigested. Humans and most livestock are not so lucky. Yes, yew can be toxic to deer, but white-tailed deer tolerate it better than most. They will strip the branches as far up as they can reach, leaving distinctive lollipop-shaped shrubbery.
As if poison fruit weren’t enough, yew also killed on the battlefield. Medieval English longbow archers dominated their world for centuries with yew bows, so much so that the domestic supply was largely cut down and the precious, very durable, but notoriously slow-growing wood had to be imported.
But the life and death duality of the yew has taken a twist the ancients could never have foreseen. The toxins that stop your heart also stop cell division in its tracks. Paclitaxel, derived initially from the Pacific yew but later from other species, is now a go-to chemotherapy for many cancers. As you cut branches for wreaths and garlands, enjoy their bright winter color, respect their murderous potential, and celebrate their life-giving powers. Maybe those tree-worshipping Druids were way ahead of their time!