| Camellia -- Ramorum leaf blight and shoot dieback | ||
| See Also: Rhododendron -- Ramorum Leaf Blight and Shoot Dieback ; and Tanoak -- Sudden Oak Death | ||
| Symptoms: Infected leaves develop dark, water-soaked lesions with defined margins. When lesion dry out they turn brown and brittle and may distort thinner leaves. Lesions on older leaves do not involve the entire leaf blade. Lesions may cover young leaves completely and then travel down the petiole and into the stem. Lesions may be difficult to see on the upper surface of some cultivars but more obvious on the lower surface. Diseased leaves generally fall off 4 to 5 days after infection even if there are no symptoms present. Defoliation is a common characteristic of this disease. Occasionally branch diebacks have been observed. Under extensive rainy conditions, flower buds may become necrotic starting first on sepals and progressing throughout the bud. Infected buds eventually abscise. | ||
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| Notes: All Camellia species, hybrids and cultivars are now regulated. Cultivar susceptibility is quite variable among the various species, hybrids and cultivars. . If you suspect you have seen a P. ramorum-infected plant in Oregon, call the Invasive Species Hotline, 1-800-INVADER (1-800-468-2337). In Oregon, the Nursery & Christmas Tree Program Supervisor at ODA must be notified if importing nursery stock from any source (out-of-state or international). Plants must be certified as free from P. ramorum and have a copy of the official certification shield. | ||
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References: Shishkoff, N. 2006. Susceptibility of Camellia to Phytophthora ramorum. Online. Plant Health Progress doi:10.1094/PHP-2006-0315-01-RS. |
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| Content edited by: Jennifer Parke on January 1, 2009 | ||
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