Think of a forest.

For many of us who live here, the suggestion conjures images of a dripping redwood grove, a deep, moist cathedral with moss and ferns, a spectacular living community built around one of California's oldest residents, the Coast Redwood. These thoughts usually belong to landscapes we know that are nearer to the ocean. Many people are surprised to learn that redwoods have a significant role in our valley as well.

In the steep canyons near the headwaters of many of our local creeks, redwoods exist, sometimes in abundance. A recent survey of the forests of Annadel State Park, especially in the areas that drain into our valley, shows that hundreds of redwoods exist in stands of various ages. Along our western hillsides there is excellent habitat for redwoods, especially in the deeper canyons where moisture is near the surface, even in dry months. The Coast Redwood, Sequoia sempervirens, exists here where climate conditions are similar enough the conditions that gave rise to this unique tree millions of years ago, a time when our changing landscape was very different.

At the time of the first redwoods, Sonoma Valley didn't exist. Their relatives evolved well over two hundred million years ago with the closing of an era in geologic history, the Paleozoic Era, and the beginning of another era, the Mesozoic. These plants were the gymnosperms, or "naked seed" plants that had perfected the ability to reproduce using a seed. They include firs, cedars, pines, hemlocks, spruces, and the now all but vanished cycads and ginko. Seed-bearing allowed these plants to tolerate new extremes in climate, a climate that had been stable for 50 million years and then abruptly was in change. The gymnosperms used their advantage to dominate forests around the world. Then, as the climate became colder they were forced to compete with the next wave of plant evolution, the angiosperms, the flowering plants with "covered seeds". Finally, glaciers of the ice ages left the gymnosperms in remnant populations, including the redwoods that survive here today.

The Coast Redwood is the world's tallest known living tree, at over 368 feet. Other redwoods are thought to have been much larger but were cut down. A redwood can pump water and nutrients from its roots to needles as high as 450 feet up, a height about 420 feet higher than a suction pump, limited to a mere 33 feet at sea level. The tree is also among the oldest. It's species name, sempervirens, refers to its "everliving" quality. Its bark can be nearly a foot thick which protects it from fire and it is full of tannin that insects can't tolerate. A redwood can be flooded and have soil deposited around its trunk, a condition that would kill most trees, and it will sprout new roots. Its trunk can be broken at almost any elevation and it will resprout or regrow. Because it is so long lived, about the only thing that will destroy it is climate change, a high wind, or human activity. When a tree does fall, it takes on a new life as a "nurse log" which is home to countless species that create the conditions from which a new adult tree can emerge. In all its life stages, the tree is one of the most significant contributors in the web of life on earth.

I have stood beside an old redwood in the valley, a tree that has been suggested to date back to the time of the Roman Empire, and felt a quiet strength, something that must be more than my imagination. I will perhaps never know for sure. I am certain that its value, like so much of life that exists just beyond my understanding, is part of what makes life on earth so amazing.