TIDAL LIFE: Hey, you! Gardener! Leave that tree alone
By NANCY BARTLETT
South Whidbey Record Columnist
October 3, 2008 · Updated 5:07 PM
“Your madrones look pretty good,” Jim said. Chainsaw idling, he stood beside a pile of firewood and brush, the remains of my dead fir.
I froze, pen poised above the check I was writing, ready to fling myself protectively in front of a peeling red trunk.
“Thanks. You sound surprised.”
The woodsman-turned-professor told me disease was attacking madrones, gave me my receipt and some experts to call and drove away. My madrones were still standing.
As much a fixture in West Coast lives as Starbucks, the Pacific Madrone, Arbutus Menzeisii Pursh, is loved by some for its scent and color, hated by others for its litterbug ways. In the 200 years since it was named, this striking, fragrant, broadleaf evergreen has been mistaken, ignored, mistreated and swept aside. Yet it feeds creatures we prize and literally holds the ground under our feet.
As a child I was captivated by that weird, peeling red bark.
When I outgrew my need to crumble things ,I enjoyed curving branches among upright evergreens and red skin glowing against shadowy cedars. Madrones were a highlight of the San Juan Island ferry trip, where giants spread glossy canopies atop granite bluffs and smaller specimens cling to the rock face.
When we built our house in a madrone grove, the attraction deepened. Walking under their arch in spring, I was enveloped in vanilla fragrance from a million blossoms. Sun-toasted summer leaves combined with nearby roses like Victorian potpourri.
In May a madrone hums as each ball-shaped flower entertains a bee. Then the skin pops open with the strain of growth, rolling into tubes that whistle when they fall. Autumn winds elicit arias from sinewy limbs, leaves clatter like castanets. Then one chilly morning, twittering robins fill the trees, gorging on scarlet berries. The season finale.
Not everyone rhapsodizes. When a pristine landscape is planned, “those messy madrones” that constantly drop leaves, must go. Jim’s experts said madrones are threatened by disease and development, and that the two were inextricably linked.
According to real estate tycoons the three rules are — location, location, location. Nowhere is the adage truer than in the world of the madrone, whose native soil is prime view property.
Retreating glaciers left huge lakes along the Pacific Coast. As the lakes receded, lake-bottom sediment became a layer of clay, the sandy deposit above formed the high bluffs where madrones took root.
When vegetation is cleared from a bluff, rainwater that was previously slowed by leaves and used by roots leaches through the soil and down to the clay layer. Where soil becomes waterlogged, the bond between it and the clay gives way — a landslide.
Coastal geologists say extensive madrone root systems play a big part in stabilizing shorelines. Plus, wide evergreen canopies act as umbrellas to the slopes, providing year-round erosion protection.
By contrast, planting grass at the top of a bluff is a primary cause of slides. Waterfront homeowners should be wary of removing madrones to plant lawns or enhance views. It could mean kissing a chunk of expensive property goodbye.
Important as madrones are in the landscape — they also feed the beautiful cedar waxwing and the endangered band-tailed pigeon — they’re touchy. Removing one from a group stresses the others by changing wind and sun access and interrupting root connections. Stress opens the remaining trees to disease, and often death, within five years.
“This reaction to isolation is typical for madrones,” says A.B. Adams, editor of The Decline of Pacific Madrone, “golf course syndrome.” Scientists don’t completely understand this sensitivity, but they advise homeowners to treat madrones carefully.
The organisms that carry diseases live within madrones. When a tree is stressed its resistance breaks down, allowing organisms to attack. This weakens the tree, leading to further disease and into full-blown decline. A dying madrone puts on a display of extravagant bloom, looking gorgeous for a couple of years to attract birds and bees to help it produce offspring.
Madrones benefit from forest fire, which destroys diseased tissue. The tree then re-grows from the intact root. But fire isn’t a favored gardening tool; instead we cut or prune diseased trees. In madrones, these practices aggravate the problem, so our best bet is to manage stress. Since no garden center sells tree tranquilizers, we must understand and meet their needs. Group tree hug.
Major stressors are change in soil level, sudden exposure to weather, over-watering, soil compaction and erosion. Construction brings all of these, unless we design buildings or gardens with trees in mind. Choose a site away from madrone roots and don’t place soil on top of existing soil around the tree. Sudden exposure to heat or cold is usually due to removal of trees that sheltered the madrone. Prevent this stress by leaving groves intact.
Pruning is unnecessary; madrones drop old branches. If you must prune, cut only dead wood and leave several inches of limb attached. The tree will heal the wound with a protective collar. Lower limbs shade the sensitive bark of the trunk, so learn to enjoy a view that includes curving branches, bird antics and the dramatic glow of sunset on red bark.
Rainfall provides all the water madrones need. Sprinkling can cause root rot. To limit compaction from foot traffic, leave native shrubbery below the tree. Children are particularly drawn to low, inviting branches. Given other care, the tree will probably take a little love from the kids.
It may be too late for my madrones. We made all the mistakes. We cut down trees that sheltered them from the weather, dug foundations close to vulnerable roots, hung rope swings from red limbs and watered. Now we’ve moved lawns and paths away and quit watering. For the moment my madrones still entertain me with scents, sounds and birdsong. I hope they’ll stick around.