Reaching for the Sky: A California Project to Clone Redwoods

SAN GERONIMO, Calif. — Two yellow-helmeted tree climbers painstakingly hoisted themselves up ropes and climbed branches to reach the top of some old-growth redwood trees at a Marin County park near here called Roy’s Redwoods. More than 200 feet above the ground they cut branches to be used to create hundreds of redwood clones.

In a couple of years, when the clones are two to three feet tall, they will be used, it is hoped, to create redwood forests in other parts of California and around the world.

Cloning has “never been done with the world’s tallest organism,” said William J. Libby, a professor emeritus of forests and genetics at the University of California, Berkeley, and a board member of the Save-the-Redwoods League. Dr. Libby has helped plant clone-seedling redwood forests in England, France, New Zealand and elsewhere since the early 1980s.

The word “cloning,” in this context, may be misleading, in that it is nothing as arcane or difficult as cloning mammals. It simply means growing a genetically identical plant. With redwoods, this is accomplished by dipping a cutting four to six inches long into a growth-hormone cocktail and then planting it in a temperature- and moisture-controlled fog chamber. Nine hundred cuttings have already been made, 300 of each of three trees sampled. It takes 20 cuttings that have grown into seedling to reforest one acre.

Using the clones of the biggest and oldest trees themselves, however, gives reforestation efforts “reliability and control you don’t have with seedlings” Dr. Libby said, because the parents of a seedling are not known.

“A whole lot of things go into living longer, and no one can say these are better trees, although they likely are,” Dr. Libby said of the cloned redwoods. “But they are icons. I’ve seen foresters cry when they’ve stood at the feet of some of these trees.”

The hope is that the near-mythical nature of the trees being cloned will fuel interest in the creation of new redwood forests around the world. Dr. Libby is helping to find suitable trees to clone and suitable planting sites.

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