Archive for December, 2004
Speeding out of town east through the tunnel, past the suburbs into the greening hills. We pay our four bills to the guy in the kiosk with the Santa hat and park our car among the horse trailers and the Subarus topped with mountain bikes. We have only our feet, a bottle of water, and a camera. We are off to visit the winter gardens of inner coastal California.
Crunch of gravel beneath our feet, a sharp breeze penetrates my wool sweater. Above us a fingernail moon floats in the electric blue sky. Waves of dried thistles cast purple shadows on the flanks of the hills. Black-green groves of bay laurel and live oak nestle in the hill folds.
We head toward the line of snaking willows, the only sign a creek lives here in this cattle-mowed savannah. December light has lit the willow limbs a ruby glow. Finches and junkos appear and disappear from the thickets. We follow the meander along the still-dry creek bed. Splayed bark reveals the reddish cambrium beneath. A buck testing his antlers for the fall rutting?
The tell-tale “M” of deer hooves in the narrow dirt trail. We follow them up the grassy slope, stooping to pick out needle sharp thistles from our pant legs. The hillsides are scored by thin parallels of cattle trails as if turned on a giant lathe. The deer prefer the hidden paths of the creek canyons, invisible from a distance.
A gust of goldfinches rises from the steep hillside like pale leaves blown in the wind. They are feeding on the thistle seeds. We stop to catch our breath. Far off on the opposite slope a duet of bicyclists attack the hill.
Following our trail back down to the creek’s alluvial plain we stop to admire the spectral beauty of an ancient buckeye tree.
Like the redwood and live oak, the california buckeye is a pleistocene relic – surviving into the eons following the Ice Ages, drought-adapted to shed its leaves in mid-summer then budding out after winter rains. Probably over two hundreds years old our tree glows in the winter light, it’s branches gilded with lichen.
Standing under the buckeye I notice a rock at my feet. It seems out of place in the grassy field. I crouch to get a better look and see the sea shells. Stuck in the sand, turned to stone and, nine million years later, mine to wonder at in the waning afternoon.
as to a question about whether Roger’s Red cultivar of the wild California grape will grow in Zone 5, here’s what I found at the Jepson Horticultural Database, a most useful project of the University of California’s Jepson Herbarium:
Information from the Jepson Horticultural Database for Vitis californica
Given no specific additional requirements, grows especially well in zone 6 and also in zones 4 and 5.
Given moderate summer watering, grows especially well in zones 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, and 24 and also in zones 7, 8, 9, 10, 11, and 12.
Cultivars available in the horticultural trade.
Hmmm… as I’m writing this I realize there is a zone identification problem. The zones referred to in the Jepson Manual are based on the Sunset Magazine gardening zones of which there are 24 that apply only to Pacific coast and western U.S. areas. (And Sunset Magazine does not allow on-line access to it’s zone index unless you subscribe to the mag.) In this system, Zone 5 is represented by coastal Oregon. The USDA climate zone system is a “plant hardiness” index based on temperature gradients and applies to the entire U.S. In this system Zone 5 is an area that can experience temperatures in the lower ranges from -10 degrees to -20 degrees.
Now I think I need to investigate how far up into the mountains the California grape will grow which may give me an idea of how cold hardy it is. There’s no easy answer to the original question….
In November the garden enters an altered state. The angle of light shifts leaving the yard in shadow where flower borders and ground dwelling plants have gone to seed or rest for the season. But up above in the garden canopy a transformation is occuring–the trees and clambering vines that during the growing months provide a subtle backdrop of greens have suddenly taken the stage in brilliant array. This year it is an extravaganza of reds. The scarlet oak reveals its dual nature for one month of the year, beginnning with the far edge of the furthest leaf on the longest limb of the towering tree. A glowing edge becomes a neon sign and finally the whole bower combusts. The fire dies out quickly to a dull doe brown where only the embers of heat remain in the leaf’s inner vein.
The dying of the light and the leaf are intertwined in the deciduous trees of the temperate zones. The longer night, it seems, is the cause. And yet, some aspects of this transformative act are probably etched in the genes of the leaf. Some will change even without the signaling long-dark periods.
Have you ever asked why the leaves turn? I confess to not having once thought about it in all my years of leaf viewing. We (the scientists, that is) know only that a green leaf is green because it is packed with cells whose only job is to turn sunlight into food (or chlorophyll) for the tree. The leaf turns to yellow at the end of its annual cycle–when it is worn out from its chlorophyll production tasks. But a leaf turning from green to scarlet is something different. Red pigment must be created by the leaf, and it uses up valuable energy when doing so. Only some trees paint themselves red in the fall but we don’t know why. Recently, it has been speculated by plant geneticists that the red pigment is a deterent to insects that might want to eat the leaf, or lay their eggs on it. The red signals poison to them. But plant physiologists have come up with a competing theory for autumn reds–sunscreen. The red pigment apparently acts as a sponge for dangerous free radicals that can burn the leaf.
Whatever their reasons for turning red, the scarlet oak and the Japanese maple in my garden are just doing what all their species do each year. The wild grape, on the other hand is a mutant and can’t be held accountable to its cousin species. A local plantsman of note, Roger Raiche, found the differently-colored grape somewhere in the hills of the East Bay. The species normally turns from green to golden yellow in the fall. Roger’s grape decided red was better. Now it is commonly seen about the town, draped over trellises and consuming lesser shrubbery and small structures. Roger’s Red, the nurseries call it.