Insects and disease

Wood borer galleries burrowed under the bark of a conifer

Forest pests and diseases are a natural part of a forest ecosystem. While most native pests or pathogens occur at low population or infection levels, there are times when they can become epidemic. Of particular concern is watching out for introduced pests and pathogens that can cause substantial problems. Forest management can influence habitat and survival of pests and pathogens.

Forest pests and disease affect forest fuels and wildfire, by killing trees and other vegetation and making them more susceptible to ignition and severe Wildfire.  Bark beetles are often singled out as the cause for tree mortality, but beetle attacks at large, catastrophic scales (1000s of acres) usually occur following a severe, multi-year drought which weakens the trees. Forests can be managed to be more resilient to drought, insect mortality, and catastrophic wildfire.

For more background on forest pests in California forests, please see:

Forest Stewardship Series 16 - Forest Pests and Diseases.

Other UC Resources:

SOD Blitz - UCCE Extension Specialist in Forest Pathology Matteo M. Garbelotto has hosted an annual SOD blitz since 2008 with coordinated sampling, production of a SOD map, and public workshops on treatment of SOD.

UCCE North Coast SOD Program - UCCE monitors for the presence of the SOD pathogen in Mendocino, Humboldt, and Del Norte Counties and is working on developing silvicultural techniques for reducing pathogen presence in forested settings.

Pests of Native California Conifers - This book is also an excellent resource http://www.ucpress.edu/book.php?isbn=9780520233294 (order) 

Other Resources:

The CalFire 2010 Forest and Rangeland Assessment Report has a chapte which describes forest pests and other threats to ecosystem health and community safety in California.

Some current forest pests of concern in California are:

• Sudden Oak Death (SOD) www.suddenoakdeath.org,
• Gold Spotted Oak Borer (GSOB) - A UC IPM pest note was released with management guidelines on GSOB in January 2013.

Identification of forest insects can be tricky. Check out the following websites for descriptions and photos of insects:

• http://www.forestpests.org/
• http://www.forestryimages.org/insects.cfm
• http://www.forestpathology.org/index.html

CALFIRE pest specialists - They help protect the state's forest resources from native and introduced pests, conduct surveys and provide technical assistance to private forest landowners, and promote forest health on all forest lands.

The US Forest Service Forest Health Protection (FHP) program - FHP is responsible for technical assistance for forest health activities; monitoring and reporting on the health of all forest lands in the Pacific Southwest Region. They work in partnership with the National Forest System, other federal agencies, states, Native American tribes and the private sector, to provide assistance, knowledge and forest health information. FHP has specialists in: forest pathology; forest entomology; pesticide use and safety; remote sensing and geographic information systems.

County Agriculture Commissioners - Each California county has an agricultural commissioner that can assist with identification of insects identification, appropriate pesticides. Commissioners also regulate pesticide use and can provide information on safe and effective use of pesticides.

California Forest Pest Council - The Council (CFPC) fosters education concerning forest pests and forest health, and advises the California Board of Forestry and Fire Protection on forest health protection. They host annual meetings and field trips for forest managers, forest pest specialists, policy makers and analysts, government agencies and anyone interested in forest health.

Forest Health and Carbon Storage in the Sierra Nevada - System Indicators: A final report to the Sierra Nevada Conservancy, December 2012. This reports on the status of Sierra Nevada forests from the standpoint of health, fire and carbon storage.

Maps

For maps of aerial surveys done by the USFS Forest Health Protection (FHP), see:  http://www.fs.fed.us/r5/spf/fhp/fhm/aerial/draft/index.shtml

http://ucanr.org/news/?uid=1262&ds=191.