Camellia: Cold injury categories: Camellia Camellia Diseases Ornamentals Shrubs revision date: 2022-11-30 12:00 Browning on camellia flower edges from cold damagePhoto by: R.S. Byther Biology Camellia leaves are sensitive to direct sunlight, which kills leaf tissue. Sunburn occurs when the shrub is planted in full sun or against a south- or west-facing wall. Winter sunlight […]
Camellia: Flower and petal blight categories: Camellia Camellia Diseases Ornamentals Shrubs revision date: 2022-11-30 12:00 Camellia flower blight: healthy vs. diseased bloomsPhoto by: OSU slide library Biology Flower and petal blight is a fungal disease of camellia flowers. Leaves, stems, and roots are not attacked. Symptoms begin with development of brown spots on the petals. […]
Camellia: Leaf gall categories: Camellia Camellia Diseases Ornamentals Shrubs revision date: 2022-11-30 12:00 Camellia leaf gallPhoto by: R.S. Byther Biology Leaf gall is caused by a fungus, and results in the formation of off-colored, thick, fleshy leaves in early spring, shortly after bud break. Through April and May, the galls are obvious and range from […]
Camellia: Oedema categories: Camellia Camellia Diseases Ornamentals Shrubs revision date: 2022-11-30 12:00 Oedema on camelliaPhoto by: B.M. Johnson Biology Oedema, or edema, is a condition which may result from excess water in the soil or high humidity. Usually found on the lower leaf surface, oedemas initially resemble protruding watery blisters or galls. Later the blisters […]
Camellia: Ramorum leaf and shoot blight (Sudden oak death) categories: Camellia Camellia Diseases Ornamentals Shrubs revision date: 2022-11-30 12:00 P. ramorum symptoms on Camellia sinensis leavesPhoto by: M. Elliott Biology Ramorum leaf blight is caused by Phytophthora ramorum, the same organism that causes sudden oak death (SOD). In Washington, most cases have been found in […]
Camellia: Sooty mold (Black mold) categories: Camellia Camellia Diseases Ornamentals Shrubs revision date: 2022-11-30 12:00 Camellia sooty mold (black mold)Photo by: R.S. Byther Biology Sooty mold is a fungal growth often found on plants infested with honeydew-producing insects, such as aphids and scales. The fungus does not attack the plant but simply grows on the […]
Camellia: Sunburn categories: Camellia Camellia Diseases Ornamentals Shrubs revision date: 2022-11-30 12:00 Sunburn on camellia leavesPhoto by: R.S. Byther Biology Camellia leaves are sensitive to direct sunlight, which kills leaf tissue. Sunburn occurs when the shrub is planted in full sun or against a south- or west-facing wall. It only takes one hot summer day […]
Camellia: Virus categories: Camellia Camellia Diseases Ornamentals Shrubs revision date: 2022-11-30 12:00 Camellia yellow mottle leaf virusPhoto by: R.S. Byther Biology The camellia yellow mottle leaf virus is transmitted by propagating from an infected plant or by grafting from an infected plant to a healthy one. Sometimes the virus is purposefully transmitted to foster variegated […]
Camellia: Aphids categories: Camellia Camellia Insects Ornamentals Shrubs revision date: 2024-06-05 02:04 Aphid colony on leafPhoto by: A.L. Antonelli Biology Camellias are infested by black citrus aphids and other aphids. The black citrus aphid is a small reddish-brown to black insect typically found on new growth and flower buds. These aphids may be found at […]
Camellia: Brown soft scale categories: Camellia Camellia Insects Ornamentals Shrubs revision date: 2024-06-05 02:04 Brown soft scalesPhoto by: R.S. Byther Biology Brown soft scales are yellowish to dark brown insects (adults are usually darker). They are found mainly on twigs, although young scales may also be found on the foliage, typically on the underside of […]
Camellia: Cottony camellia scale categories: Camellia Camellia Insects Ornamentals Shrubs revision date: 2024-06-05 02:04 Cottony camellia scale on holly leavesPhoto by: A.L. Antonelli Biology The cottony camellia scale is a flat brownish or yellowish insect. The scales overwinter on twigs or evergreen leaves. In the spring, adult females lay cottony egg masses on the underside […]
Camellia: Root weevils categories: Camellia Camellia Insects Ornamentals Shrubs revision date: 2023-04-04 12:00 Root weevil larval damagePhoto by: A.L. Antonelli Biology Root weevils are small flightless beetles with a snout. The adults are black or mottled and approximately 1/4″ long, depending on species. They feed on the leaves by crawling up the stems and chewing […]
Boxwood: Boxwood leafminer categories: Boxwood Boxwood Insects Ornamentals Shrubs revision date: 2023-04-04 12:00 Boxwood leafminerPhoto by: A.L. Antonelli Biology Leafminers feed by removing green tissue from between the upper and lower leaf surfaces. Feeding by leafminers can be detected by the presence of yellow to brownish blotch-like mines or by a blistered, thickened appearance of […]
Boxwood: Boxwood mite categories: Boxwood Boxwood Insects Ornamentals Shrubs revision date: 2024-06-05 02:04 Spider mites under microscopePhoto by: L.K. Tanigoshi Biology Boxwood mites are small and greenish brown. Their presence is typically indicated by small white, yellow, or bronze streaks resembling fine scratches or speckles on the upper surface of leaves. The mites may be […]
Boxwood: Boxwood psyllid categories: Boxwood Boxwood Insects Ornamentals Shrubs revision date: 2024-06-05 02:05 Boxwood psyllidPhoto by: K. Grey Biology The presence of the boxwood psyllid is indicated by the cupping of leaves at the tips of terminals. The white immature psyllids (nymphs) feed on the developing buds and leaves at the tips of branches, causing […]
Boxwood: Box blight categories: Boxwood Boxwood Diseases Ornamentals Shrubs revision date: 2022-11-30 12:00 Box blight brown leaf spots and defoliationPhoto by: J. Glass Biology Box blight is a fungal disease that causes leaf spots, stem cankers or black streaks, and foliar blight, and defoliation. Symptoms of blight and defoliation can appear suddenly and affected plants […]
Boxwood: Canker categories: Boxwood Boxwood Diseases Ornamentals Shrubs revision date: 2022-11-30 12:00 Boxwood cankerPhoto by: R.S. Byther Biology Boxwood canker is caused by a fungus which often infects branches through pruning wounds or at branch crotches, where infected, dead leaves have accumulated. Leaves of affected branches often change color to light green, yellow, then tan. […]
Boxwood: Leaf spot categories: Boxwood Boxwood Diseases Ornamentals Shrubs revision date: 2022-11-30 12:00 Boxwood Pseudonectria leaf spotPhoto by: R.S. Byther Biology Boxwood leaf spot is caused by fungi which survive in fallen, diseased leaves beneath the plant. Leaves develop discolored spots and may turn tan or brown from the margins and tips inward. Small, black […]
Boxwood: Phytophthora root rot categories: Boxwood Boxwood Diseases Ornamentals Shrubs revision date: 2022-11-30 12:00 Phytophthora root rot infecting trunkPhoto by: C.R. Foss Biology Phytophthora is a fungal infection of the roots and crown. Infected plants often show wilting, discolored or dead leaves which remain on the branches, dead twigs and branches, stunting, gradual decline, and […]
Bamboo: Aphids categories: Bamboo Bamboo Insects Ornamentals Shrubs revision date: 2024-06-05 02:04 Aphid colony on leafPhoto by: A.L. Antonelli Biology Aphids on bamboo are yellowish to light green insects with pear-shaped bodies. They typically feed in large clusters on the underside of leaves and may produce large amounts of honeydew. The shiny, sticky honeydew can […]