True Fir

True Fir: Balsam woolly adelgid

True Fir: Balsam woolly adelgid categories: Conifers Ornamentals True Fir True Fir Insects last review date: 2026-01-29 12:43 Balsam woolly adelgid damagePhoto by: R.S. Byther Biology The balsam woolly adelgids 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, […]

True Fir: Giant conifer aphids

True Fir: Giant conifer aphids categories: Conifers Ornamentals True Fir True Fir Insects last review date: 2026-01-29 01:00 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 […]

True Fir: Annosus root rot

True Fir: Annosus root rot categories: Conifers Ornamentals True Fir True Fir Diseases last review date: 2026-01-29 12:02 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 […]

True Fir: Armillaria root rot

True Fir: Armillaria root rot categories: Conifers Ornamentals True Fir True Fir Diseases last review date: 2026-01-29 12:13 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 […]

True Fir: Current-season needle necrosis

True Fir: Current-season needle necrosis categories: Conifers Ornamentals True Fir True Fir Diseases last review date: 2026-01-29 12:49 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 […]

True Fir: Flowers

True Fir: Flowers categories: Conifers Ornamentals True Fir True Fir Diseases last review 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. […]

True Fir: Grovesiella canker

True Fir: Grovesiella canker categories: Conifers Ornamentals True Fir True Fir Diseases last review date: 2026-01-29 01:10 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 […]