Statewide Attack Sought for Pine Pitch Disease

A relentless and incurable disease that first struck Monterey pines in Santa Cruz and southern Alameda County 10 years ago, has spread into 17 coastal counties and threatens to invade the Sierra, Coast, and Cascade Ranges, prompting an appeal for help at the statewide level.

The insidious pine pitch canker disease, carried by 10 species of bark, cone, and twig beetles, has killed hundreds of trees, and no end is in sight.

"I don't want to sound like Chicken Little, but this disease has grown by leaps and bounds," Gary Kelly, director of the Caramel Department of Forests, Parks, and Beaches, told the California Biodiversity Council in Oxnard Sept. 19.

"When you watch it move throughout the forest, and you really can't do anything about it, you don't have much hope," Kelly said. In Carmel alone, 132 trees showed pitch canker symptoms three years ago, and now, the disease is evident in close to 600 trees, he said.

Pine pitch canker was first found in California in a Monterey pine at New Brighton State Beach in Santa Cruz, pictured here.

Kelly is co-chair of the Pine Pitch Canker Task Force, a subcommittee of the California Forest Pest Council that includes the state Departments of Forestry and Fire Protection, Fish and Game, Parks and Recreation, U.S. Forest Service, University of California at Berkeley, Monterey County Agricultural Commissioner's Office, San Luis Obispo County Department of Agriculture, and other local and nonprofit groups.

Pine pitch canker occurs in the southeastern United States, Haiti, Mexico, South Africa, and Japan. It is assumed to have been brought into California by visitors or commercial interests, perhaps on firewood from the southeast, or lumber from Mexico. When the disease was first noticed in 1986 at New Brighton State Beach in Santa Cruz, and in the Union City-Fremont area, a proposal to remove the infected trees was rejected. By then, the disease was already widespread, and tree removal was deemed too costly, troublesome for disposal, and objectionable to the public, since the trees showed little or no outward signs of disease.

Now, the fungus is spread up and down the coast, infecting trees from San Diego to Mendocino, too many to remove. Researchers at the University of California, Berkeley, are hoping to develop a resistant strain, but the only defense so far is educating the public about all of its aspects.

How to Recognize It
Monterey pine has grown naturally in California since pre-historic times, but today, most of it is planted, except for three native stands -- Monterey, Ano Nuevo State Reserve north of Santa Cruz and Cambria, a community north of San Luis Obispo.

The tree, planted statewide, is most susceptible to pine pitch canker, but at least eight other native pines are vulnerable, including its close relative, Bishop pine, and the popular Christmas tree, Douglas fir.

Interestingly, pine pitch canker shows no visible signs during the latent period when it first infects a tree, but eventually, the fungus appears as cankers on the woody parts, including cones, branches, trunk, and exposed roots. It infects branches from the tips down, turning them a brownish orange, and creates an excessive pitchy flow of amber resin that runs down the trunk. Infected trees usually die in about four years after being weakened and finished off by bark beetles.

Insects spread the disease locally, but long-distance movement is believed to be caused by humans transporting infected logs, firewood, wood chips, Christmas trees, seedlings, cones, pruning tools, and other woody material.

The California Department of Forestry and Fire Protection advises consumers to recognize the disease, avoid transporting contaminated materials and items, and carefully clean tools used on infected trees with a disinfectant.

Dave Adams, a CDF pathologist who has been working on the pine pitch canker problem since its outbreak, said if the disease wipes out different strains of Monterey pine, it will threaten the genetic diversity that enables the tree to establish and sustain itself in various soils and climates.

"Monterey pine is an important player in its ecosystem, which is very fragile," Adams said. "Other plants co-exist with it, even depend upon it. Once you change the composition of the Monterey pine stands, you affect all the other parts of that ecosystem, and you can't put it back together again."

In seeking the support of the agencies on the Council, Kelly explained that communities alone cannot stop the disease.

"It's too big to deal with on the local or regional level," Kelly said. "We need a broad-based state effort to address the situation. Once it reaches the epidemic point, the disease won't follow any logical progression. It takes on a life of its own."

Council Chair Doug Wheeler, California's secretary for resources, asked the task force to recommend a statewide course of action. The Council will take up the issue at its winter meeting Dec. 12 in Sacramento.

Recommendations
Because there is no cure for pine pitch canker, and eradication is not a viable option, the task force is focusing on public education and research, and already have held two symposiums.

The task force is compiling a data base of people they want to inform or communicate with about pine pitch canker. The group also intends to designate representatives in each infested county to serve as a conduit for information and help assemble mailing lists for public and news media notification.

Brochures, research updates, posters, and other literature about pine pitch canker is available, and the Pacific Grove Natural History Museum has created a three-dimensional display. Presentations are planned for conferences, meetings, county fairs, tree growers, foresters, environmentalists, and others.