Douglas Fir: Spruce spider mite categories: Conifers Douglas Fir Douglas Fir Insects Ornamentals revision date: 2024-06-05 02:04 Spruce spider mite adultPhoto by: A.L. Antonelli Biology The presence of spruce spider mites is indicated by yellow or bronze stippling beginning near the needle bases. Infestations usually begin on older needles of the lower branches and spread […]
Douglas Fir: Armillaria root rot categories: Conifers Douglas Fir Douglas Fir Diseases Ornamentals revision date: 2023-01-31 12:00 White fungal mat of Armillaria root rot infecting trunkPhoto by: C.R. Foss Biology Armillaria root rot is a fungal disease transmitted between plants by root contact. Armillaria is often found in newly cleared soils or ones which have […]
Douglas Fir: Laminated root rot categories: Conifers Douglas Fir Douglas Fir Diseases Ornamentals revision date: 2023-01-31 12:00 Staining in wood (James) and wind-thrown tree (Wallis) R.L. James (wood), G.W. Wallis (tree); Bugwood.org Biology Laminated root rot is a fungal disease of conifers throughout the Pacific Northwest. Douglas-fir, grand fir, and mountain hemlock are highly susceptible […]
Douglas Fir: Rhabdocline needle cast categories: Conifers Douglas Fir Douglas Fir Diseases Ornamentals revision date: 2024-06-05 02:07 Douglas-fir Rhabdocline needle castPhoto by: R.S. Byther Biology The first symptoms of this fungal infection are many tiny yellow spots on the current season’s needles appearing in late summer or fall. By spring, these spots have expanded and […]
Douglas Fir: Rust categories: Conifers Douglas Fir Douglas Fir Diseases Ornamentals revision date: 2023-01-31 12:00 Douglas-fir Melampsora rustPhoto by: G.A. Chastanger Biology Rust is a fungal disease infecting the needles of Douglas fir. Wind-blown spores infect the new needles in the spring. Yellow to orange bumps, or pustules, are found on the underside of needles […]
Douglas Fir: Stem cankers categories: Conifers Douglas Fir Diseases Ornamentals revision date: 2023-01-31 12:00 Douglas-fir stem cankerPhoto by: Unknown Biology Stem cankers on Douglas fir are sunken and oval, occurring on branches or new shoots. Each canker is typically centered around a dead twig and can be small or up to 30″ long or more. […]
Douglas Fir: Swiss needle cast categories: Conifers Douglas Fir Douglas Fir Diseases Ornamentals revision date: 2024-06-05 02:07 Douglas-fir Swiss needle castPhoto by: R.S. Byther Biology This fungal disease causes infected needles to become off-color and mottled yellow or brown. The needles may turn completely brown and are usually dropped prematurely, often in early spring. Infected […]
Douglas Fir: Upper stem canker categories: Conifers Douglas Fir Douglas Fir Diseases Ornamentals revision date: 2024-06-05 02:07 Douglas-fir upper stem cankerPhoto by: R.S. Byther Biology Upper stem cankers are caused by fungi in the soil. Seedling Douglas fir trees are affected, with the tops of infected trees turning yellow. By fall, the tops turn reddish-brown. […]
Douglas Fir: Yellow-green mottle syndrome categories: Conifers Douglas Fir Douglas Fir Diseases Ornamentals revision date: 2023-01-31 12:00 Douglas-fir yellow-green mottle syndromePhoto by: G.A. Chastanger Biology he cause of yellow-green mottle syndrome is unknown, but may be genetic. Needles of all ages are affected by yellow-green mottle syndrome. Yellow-green blotches may be small or may cover […]
Cedar: Cedar flagging categories: Cedar Conifers Ornamentals revision date: 2023-02-08 12:00 Cedar flaggingPhoto by: R.S. Byther Biology Evergreen plants naturally shed some old foliage each year. Stress factors, such as lack of sufficient water, hot winds, construction damage or other root disturbance, poor planting procedures, or recent planting can promote flagging. Brown foliage develops on […]
Cedar: Leaf blight categories: Cedar Conifers Ornamentals revision date: 2024-06-05 10:24 Arborvitae Didymascella leaf blightPhoto by: R.S. Byther Biology Leaf blight is a fungal disease. The symptoms typically appear first in late spring as bleached spots followed by brown or black cushion-like fungal fruiting bodies. Infected foliage may be anywhere on the plant. Individual leaves […]
Cedar: Port Orford cedar root rot categories: Cedar Conifers Ornamentals revision date: 2023-02-08 12:00 Phytophthora root rot infecting trunkPhoto by: R.S. Byther Biology Phytophthora root rot on Port Orford cedar is usually a problem only in areas with poor drainage or where flooding occurs. The fungus attacks the roots, which rot and die. The infection […]
Cedar: Seiridium canker categories: Cedar Conifers Ornamentals revision date: 2023-02-08 12:00 Seiridium cankerPhoto by: M. Harris Biology Seiridium cardinale and Phaeobotryon cupressi are fungal pathogens which cause yellowing or browning of the foliage. The result is flagging, the dieback of branch tips and entire branches of trees in a random distribution throughout the canopy. Cankers […]
Arborvitae: Cypress tip moth categories: Arborvitae Arborvitae Insects Conifers Ornamentals revision date: 2024-06-05 02:07 Arborvitae cypress tip moth damagePhoto by: R.S. Byther Biology The adult cypress tip moth (cypress tip miner) is a silver-tan moth approximately 1⁄4″ in length. The larvae are green, about 1⁄8″ long, and tunnel in the one- and two-year-old shoot tips. […]
Arborvitae: Flat-headed and shothole borers categories: Arborvitae Arborvitae Insects Conifers Ornamentals revision date: 2023-02-07 12:00 Shothole borer infestation holesPhoto by: A.L. Antonelli Biology Flat-headed borer attacks are most severe on declining plants. The 1⁄2″ adults are either brown to metallic gray or black with red or orange markings, depending on species. The larvae mine under […]
Arborvitae: Juniper scale categories: Arborvitae Arborvitae Insects Conifers Ornamentals revision date: 2024-06-05 02:05 Juniper scalePhoto by: Unknown Biology Juniper scale is a small, round, white to gray scale with a yellow dot at the center. Leaves, twigs and branches may be attacked. Symptoms of scale feeding include loss of normal color and luster of foliage, […]
Arborvitae: Juniper webworm categories: Arborvitae Arborvitae Insects Conifers Ornamentals revision date: 2024-06-05 02:10 Juniper webworm damagePhoto by: A.L. Antonelli Biology The adult juniper webworm is a copper-brown moth with white bands on the edges of the front wings. The moth is about 1⁄2″ across. The webworm caterpillars initially feed by mining inside leaves. As they […]
Arborvitae: Berckmann’s blight categories: Arborvitae Arborvitae Diseases Conifers Ornamentals revision date: 2024-06-05 10:24 Arborvitae Berckmann’s blightPhoto by: R.S. Byther Biology Berckmann’s blight is a fungal disease of the leaves and small twigs of Oriental arborvitae. Growth at the tips of branches is infected first, turning brown in late spring. As the infection moves down the […]
Arborvitae: Cedar flagging categories: Arborvitae Arborvitae Diseases Conifers Ornamentals revision date: 2023-02-07 12:00 Cedar flaggingPhoto by: R.S. Byther Biology Evergreen plants naturally shed some old foliage each year. Stress factors, such as lack of sufficient water, hot winds, construction damage or other root disturbance, poor planting procedures, or recent planting can promote flagging. Brown foliage […]
Arborvitae: Leaf blight categories: Arborvitae Arborvitae Diseases Conifers Ornamentals revision date: 2024-06-05 10:24 Arborvitae Didymascella leaf blightPhoto by: R.S. Byther Biology Leaf blight is a fungal disease. The symptoms typically appear first in late spring as bleached spots followed by brown or black cushion-like fungal fruiting bodies. Infected foliage may be anywhere on the plant. […]