Sudden Oak Death California Department of Food and

Sudden Oak Death California Department of Food and Agriculture

Phytophthora ramorum - SOD • Caused by the fungus-like organism Phytophthora ramorum. • First identified in 1993 in Germany and the Netherlands on Rhododendron and Viburnum. • 1995 - a new disease killing tanoak and oak trees was observed in California. In 2000, the pathogen was confirmed to be P. ramorum. • Natural infections limited to Europe, California and a small portion of Oregon. • Problem in plant nurseries!

Sudden Oak Death • Related to Phytophthora infestans, the causal agent of late blight of potato • Soil-borne organism, which can cause root, canker, and above-ground infections. • Spread by soil and water splash (irrigation, rain, wind-blown rain…). • Favored by relatively cool temperatures (68 F) and high moisture.

SOD - Hosts • Coast Live Oak (Quercus agrifolia) • Tanoak (Lithocarpus densiflorus) • Shreve’s Oak (Quercus parvula v. • Canyon Live Oak (Quercus • Bigleaf Maple (Acer macrophyllum) • Madrone (Arbutus menziesii) • Manzanita (Arctostaphylos • Coast Redwood (Sequoia • shrevei) manzanita) chrysolepis) sempervirens) • Douglas-Fir (Pseudotsuga menziesii) • Wood Rose (Rosa gymnocarpa) • California Buckeye (Aesculus californica) • • Camellia Pieris Rhododendron & Azalea Viburnum California Bay Laurel (Umbellularia californica) • California Honeysuckle (Lonicera hispidula)

SOD- Associated Hosts • Grand Fir (Abies grandis) • Horse-Chestnut (Aesculus hippocastanum) • Strawberry Tree (Arbutus unedo) • Mountain Laurel (Kalmia latifolia) • Victorian Box (Pittosporum undulatum) • Southern Red Oak (Quercus falcata) • Northern Red Oak (Quercus rubus) • Poison Oak (Toxicodendron diversiloba) • European Yew (Taxus baccata) • Lilac (Syringa vulgaris) • California Hazelnut (Corylus cornuta) • Sweet Chestnut (Castanea sativa) • Formosa Firethorn (Pyracantha koidzumii)

Distribution of SOD in CA

Sudden Oak Death Oak Symptoms

Sudden Oak Death Tanoak – shoot dieback and branch canker Viburnum Shoot dieback Maple - tipburn Rhododendron – leaf blight

Sudden Oak Death Treatment? • There are currently no treatments recommended for naturally infected areas. • Fungicide sprays may be used to help reduce disease in nurseries. • Eradication is being attempted in many areas where the pathogen has been detected – burning, deep burial, disinfection of contaminated area. • Continue and increase the National Survey - CAPS.

• http: //www. cnr. berkeley. edu/comtf/index. html • http: //www. invasivespecies. net/database/welcome/ National Forest Health Monitoring Øhttp: //fhm. fs. fed. us/sp/sod. shtm