Fact Sheets

Yew: Cottony camellia scale

Yew: Cottony camellia scale categories: Conifers Ornamentals Yew Yew Insects revision date: 2024-04-08 11:46 Cottony camellia scale on yewPhoto by: A.L. Antonelli Biology The adult cottony camellia scale is a flat, oval, brownish insect. It is also found on holly and camellia. The scales overwinter on twigs or needles. In the spring, adult females lay […]

Yew: Lecanium scale

Yew: Lecanium scale categories: Conifers Ornamentals Yew Yew Insects revision date: 2024-04-08 11:46 Lecanium scales on twigPhoto by: R.S. Byther Biology Lecanium scales are shiny brown insects found on leaves and twigs. Adults are 1⁄8″-1⁄4″ in diameter and roughly turtle-shaped. Crawlers (immature scales) are flatter. Scales produce large amounts of honeydew, a sweet, sticky material […]

Yew: Root weevils

Yew: Root weevils categories: Conifers Ornamentals Yew Yew Insects revision date: 2023-04-04 12:00 White pine weevil damage on spruce close-upPhoto by: C.G. Landgren Biology Root weevil larvae feed on the roots and bark of plants near the crown. The white grubs are found in the soil around the roots. Larval feeding can cause significant damage, […]

True Fir: Balsam twig aphid

True Fir: Balsam twig aphid categories: Conifers Ornamentals True Fir True Fir Insects revision date: 2023-04-04 12:00 Balsam twig aphidPhoto by: A.L. Antonelli Biology Balsam twig aphids feed on needles and buds of firs. Three distinct forms of the balsam twig aphid occur. Aphids may be (1) small and yellow-green, (2) large and bluish-gray, or […]

True Fir: Balsam woolly adelgid

True Fir: Balsam woolly adelgid categories: Conifers Ornamentals True Fir True Fir Insects revision date: 2023-02-07 12:00 Balsam woolly adelgid damagePhoto by: R.S. Byther Biology The balsam woolly adelgid feeds on the stems of true firs. White or grayish cotton-like masses, inside which are the purplish-black insects, can be found on the twigs, branches, or […]

True Fir: Coneworms

True Fir: Coneworms categories: Conifers Ornamentals True Fir True Fir Insects revision date: 2023-02-07 12:00 Coneworm larvae on pinePhoto by: K. Grey Biology Coneworms attack trees by boring into shoot tips or stems, especially around wounds, and feeding on the soft bark tissues. Tip dieback may result from coneworm feeding. They may also bore into […]

True Fir: Giant conifer aphids

True Fir: Giant conifer aphids categories: Conifers Ornamentals True Fir True Fir Insects revision date: 2023-04-04 12:00 Giant conifer aphids on pinePhoto by: A.L. Antonelli Biology Giant conifer aphids are large (up to 1⁄5″) and dark brown to black in color. They overwinter as eggs on twigs or branches. Adults and nymphs begin feeding on […]

True Fir: Spruce budworm

True Fir: Spruce budworm categories: Conifers Ornamentals True Fir True Fir Insects revision date: 2023-04-12 12:00 Caption: Spruce budwormPhoto by: T.J. Fitzgerald Biology These larvae feed on the buds and foliage and may tie shoot tips together with webbing to make a nest. They are typically green to brown in color with a darker head […]

True Fir: Annosus root rot

True Fir: Annosus root rot categories: Conifers Ornamentals True Fir True Fir Diseases revision date: 2023-02-07 12:00 Annosus root rot decayed wood with black flecksPhoto by: B.M. Johnson Biology Annosus root rot is caused by the fungus Heterobasidion annosum. This native soil pathogen is often in large old tree stumps. It can live several decades […]

True Fir: Armillaria root rot

True Fir: Armillaria root rot categories: Conifers Ornamentals True Fir True Fir Diseases revision date: 2023-02-07 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 soils which have […]

True Fir: Current-season needle necrosis

True Fir: Current-season needle necrosis categories: Conifers Ornamentals True Fir True Fir Diseases revision date: 2023-02-07 12:00 Current-season needle necrosisPhoto by: R.S. Byther Biology Current-season needle necrosis affects noble fir and grand fir. The cause is unknown, but appears to be a cultural problem due to a mineral deficiency. Shortly after growth begins, the current […]

True Fir: Flowers

True Fir: Flowers categories: Conifers Ornamentals True Fir True Fir Diseases revision date: 2023-02-07 12:00 Fir flowersPhoto by: R.S. Byther Biology Old, spent flower parts remaining on twigs can be misinterpreted as a disease or insect problem or an unusual growth anomaly. Management Options Use Integrated Pest Management (IPM) for successful plant problem management. Non-chemical […]

True Fir: Grovesiella canker

True Fir: Grovesiella canker categories: Conifers Ornamentals True Fir True Fir Diseases revision date: 2023-02-07 12:00 Fir Grovesiella cankerPhoto by: R.S. Byther Biology Grovesiella canker is a fungal disease found mainly on the lower branches and stems of young trees or the lower branches of older trees. Sunken, dead areas develop on one-year-old and older […]

True Fir: Interior needle blight

True Fir: Interior needle blight categories: Conifers Ornamentals True Fir True Fir Diseases revision date: 2023-02-07 12:00 Interior needle blightPhoto by: G.A. Chastanger Biology Interior needle blight is found primarily on noble fir in Christmas tree plantings, but may also occur in the landscape. While a fungus has been associated with the disease, other factors […]

True Fir: Needle casts

True Fir: Needle casts categories: Conifers Ornamentals True Fir True Fir Diseases revision date: 2023-02-07 12:00 Fir needle cast symptomsPhoto by: R.S. Byther Biology Needle casts on true fir are caused by several fungi. Infected trees develop brown or straw-colored needles which drop prematurely. Severely infected trees may have only current-season and one-year-old needles. The […]

True Fir: Phytophthora root rot

True Fir: Phytophthora root rot categories: Conifers Ornamentals True Fir True Fir Diseases revision date: 2023-02-07 12:00 Phytophthora root rot symptomsPhoto by: R.S. Byther Biology Phytophthora root rot 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 moves up […]

True Fir: Rust (Pucciniastrum)

True Fir: Rust (Pucciniastrum) categories: Conifers Ornamentals True Fir Diseases revision date: 2023-02-07 12:00 Fir Pucciniastrum rustPhoto by: R.S. Byther Biology Pucciniastrum rusts are fungal diseases. Yellowish spots or blotches appear on the upper side of infected needles. White, tube-like structures are typically found on the underside of last season’s needles in early summer or […]

True Fir: Spruce spider mite

True Fir: Spruce spider mite categories: Conifers Ornamentals True Fir True Fir Insects revision date: 2023-02-07 12:00 Spruce spider mite adultPhoto by: A.L. Antonelli Biology The presence of spruce spider mites is indicated by yellow or bronzish stippling beginning near the needle bases. Infestations usually begin on older needles of the lower branches and spread […]

True Fir: Rust (Uredinopsis)

True Fir: Rust (Uredinopsis) categories: Ornamentals True Fir True Fir Diseases revision date: 2023-02-07 12:00 Fir Uredinopsis rustPhoto by: R.S. Byther Biology Uredinopsis rust is a fungal disease. Yellowish spots or blotches appear on the upper side of infected needles. A slight discoloration may first be observed on current-season needles in fall or winter. White, […]

True Cedar (Cedrus): Needle blight

True Cedar (Cedrus): Needle blight categories: Conifers Ornamentals True Cedar revision date: 2023-02-08 12:00 Shoot needle blight on cedarPhoto by: R.S. Byther Biology Certain fungi have been associated with needle blight on Atlas and Deodora cedars. In spring, infected needles turn a tan-pink color. The blight may be only on the new shoots or may […]