Our View: Will coastal redwoods be history?

May 17, 2007 12:00 am

Certainly one of the many reasons Del Norte County is a great place to live is its natural beauty of lush redwood forests meeting the dramatic ocean coastline.

Though global warming likely will wreak havoc with the aquatic life in the ocean, at least the coastline view will remain. The prognosis for our redwood and inland forests is much less certain, however.

Imagine a coast in which only a handful of redwoods are able to survive. Inland, wildfires have devastated thousands of acres of forests, opening the way for oak trees to dominate. Most native plants have disappeared, replaced by invasive species that change the very look and feel of the landscape.

It's all too real of a threat, and is only a decade or two from reaching a tipping point where there is no going back to the Del Norte County that we now know.

Perhaps the greatest loss will be a significant reduction in the number of redwoods – an ancient giant of which more than 90 percent of the population already has been lost to logging and development. "Forest stands that require relatively cool conditions may not be able to adjust to the relatively rapid warming that is being predicted," a NASA report warns. As air and ocean temperatures rise, the fog that cools and provides precipitation to the redwoods will decline markedly.

The most immediately evident loss will be seen inland from Hiouchi to the Oregon and Siskiyou County borders: The destruction and loss of spruce forests. We can expect that late winters and springs will be far drier – which is happening this year – resulting in drier conditions, according to a UC Irvine study published earlier this year. This opens the way for wildfires. As warmer temperatures allow destructive insects and diseases to take root, the trees native to inland forests will have great difficulty regaining ground. Expect black oak, a species better suited to grow in the new climate to take hold.

The landscape along the coast, from Crescent City to Smith River, also will change. As global warming alters air circulation patterns over the Pacific Ocean, precipitation will fluctuate along the coast, the UC Irvine study notes. This disruption will allow invasive plant species – such as tansy ragwort, Scotch broom, English ivy, European beach grass – to become even more prevalent. Such plants dramatically alter water and nutrient cycles, pushing out native plants and forcing native animals to shift their ranges. Some invasive plants, such as the tansy ragwort, also pose a threat to livestock.

The reality is that global warming isn't just warmer and longer summers or the melting of glaciers thousands of miles away. It's also about dramatically altering the very landscape that Del Norters cherish and love. It's a good reason for all of us to be concerned about global warming.