Worlds Apart

There are creamy yellow blossoms of mountain mahogany, blossoms of California bay, the passion-flower-like virgin’s bower (the cream-white native clematis) and the rest of the cream meme – star florets of wild cucumber, flat-top elderberry blossoms, pendulous poison oak flowers and the miniature grape-like flower clusters of its close relative, squaw bush - cream on grey skeletal twigs. The tiny fuzz balls on the mule fat (baccharis salicifolia) are the color of a tea-stained linen napkin while the local morning glory is whiter, but replete with red wine streaks on the exterior of its trumpet.

There are the blues of lupine, the nightshades, fiesta flowers, blue eyed grass and blue dicks and now sage; white popcorn flower, white California everlasting and the black to carmine of the California peony blossoms.

Most of the white ceanothus flowers were lost to the winds of late February and early March but there is still the blue. Owl’s head clover, tending deep pink, has pushed up in drifts amidst grasses, invasive erodium and clover; pink prickly phlox is set in sandstone cliffs and at the damp base, coral Indian paintbrush. The bush poppies and bush sunflowers provide splashes of yellow (along with the tiny punctuation of fiddlenecks) amidst the chaparral’s mostly blue, white, cream and pink flowers.

This efflorescence is a tiny slice of the local botanical diversity. As Lightfoot and Parrish point out in their California Natural History Guide, California Indians and their Environment, 2009,

"California is home to more endemic species of plants...than any other equivalent sized area in North America. 3,423 species are considered to be native and another 1,416 are classified as endemic, i.e. they are found only in habitats within the state. Nearly 25% of all known plant species in the United States are found in California. These include the world's tallest trees, the coast redwood (sequoia sempiverens), the world's largest trees, the giant sequoia (sequoiadendron giganteum); the worlds oldest trees, the western bristlecone pine (pinus longeava); and some of the smallest and unique plants known to mankind."

By contrast, as my friend Will Reed reminded me the other morning, Britain possesses only 32 (or maybe 35) native trees and 32 native shrubs, of which only one, an obscure hornbeam, is endemic. Yes, there are some 1,500 grasses and forbs native to the Old Dart, but Britain was wiped clean of flora during the massive glaciations which began around 100,000 years ago and has half the biotic diversity of its cross-channel neighbor France (quelle dommage!).

After the end of the last Ice Age, plants slowly re-colonized Britain in their general drift towards the northwest as the climate improved and the range of species was extended. However, about 8,000 years ago, with continued ice-melt, the rift between Britain and France was submerged in a cataclysmic megaflood fed by the rising waters of a vast freshwater lake formed over many thousands of years in what is now the southern north sea. This devastating surge of water pounded and gouged the land, creating a giant channel between the two land masses. This newly formed English Channel then halted terrestrial migration of plants from the rest of Europe, forever limiting Britain's native biotic diversity. (Sanjeev Gupta et al. in Nature 448, 2007)

It is interesting to note the comparative ages of human inhabitation in California and Britain. As I have detailed in Ancient Isle, the first humans arrived in California, perhaps via the Kelp Road (and if so, perhaps on the Northern Channel Islands) about 15,000 years ago during the last groans of the mega fauna.

Some 700,000 years before, early humans were mixing it up with hippos, rhinos and elephants along the banks of a vast meandering river that drained central and eastern England and flowed sluggishly into the North sea. This, of course, was millennia before Britain separated from Europe and the warm interglacial period afforded opportunities for settlement in the continent's northern reaches - what today is Suffolk and Norfolk. (Simon Parfitt et al. in Nature 438, 2005)

It is tempting to view the protracted isolation from the uber-predator as the reason for California's biotic fecundity. But, as I mention in WEIRD, human populations can sometimes foster biotic diversity and certainly the absence of pre-historic agriculture went some way towards preserving California's variety of plant-life - many of whose species native peoples incorporated into their food, medicine, craft and buildings. There are more profound, climatic and geological reasons why this 'Floristic Province' is now designated by Conservation International as a Global Biodiversity Hotspot.

Over the last 2 1/2 million years, California largely avoided the ravages of the Ice Ages. Instead, the coastal areas were characterized by grassy plains with rich sediments deposited by rivers meandering their way to the ocean. Seismic activity has bounced some of these old beaches inland and old sea floors now form our mountain tops. Old wave-cut ocean terraces step down towards the present-day coastline. Streams have cut through the up-lifted land mass and created deep valleys. As the climate warmed and sea levels rose these valleys were flooded to form estuaries rich in the deposition of soft sediments, which have eroded and spread their riches down stream as sea levels have dropped again (viz. the Oxnard Plain). Over time, these processes have shaped California’s unique habitats and produced a rich mosaic of life. Now, the cold ocean currents to the west and high mountains to the east have formed, in Carey McWilliams' phrase, an island on the land, where California's dizzying diversity is nurtured in its short wet winters and long dry summers.

The other evening on the pool terrace, drinking a Page tangerine cocktail (equal parts juice, Campari, and soda), with Jim Churchill, the drink's originator, he looked across at the east hill and asked, what is that pink bush mid-slope? It was at that hour when the world is suffused with an apricot blush (resonating with the color of our drinks) when the low sun, filtered through the planet's dust, casts its glow across the spalled cliff face of the Topatopas. I had no answer, but assured him that I would investigate the following morning.

Walking through the east meadow past the oaks and walnuts, I pushed through the chamise up the slope until I had a clear view of Jim's pink bush. In the morning light it was a more prosaic beige and it was apparent that the color belonged to a frost damaged bough of laurel sumac. In this floristic paradise, it is easy to imagine flowers where none exist.

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