Hawthorn: Apple-and-thorn skeletonizer Categories: Hawthorn Hawthorn Insects Ornamental trees Ornamentals Last review date: 2026-09-29 06:57 Last edit date: Apple-and-thorn skeletonizer caterpillar feeding on leaf Photo by: A.L. Antonelli Biology The adult of the apple-and-thorn skeletonizer is a small dark-brown moth. It overwinters as an adult, laying eggs in the spring. The caterpillars are yellow green […]
Hawthorn: Hawthorn aphid Categories: Hawthorn Hawthorn Insects Ornamental trees Ornamentals Last review date: 2026-09-29 06:57 Last edit date: Green peach aphid closeup Photo by: Unknown Biology Hawthorn aphids are yellow green to pinkish, soft-bodied insects typically found on the leaves in the spring. Aphid feeding causes young leaves to curl tightly and turn purplish. Older […]
Hawthorn: Pear slug Categories: Hawthorn Hawthorn Insects Ornamental trees Ornamentals Last review date: 2026-05-15 09:08 Last edit date: Pear slug and damaged leaf from feeding Photo by: R.D. Akre Biology Pear slugs, or pear sawflies, are insect larvae which resemble a small greenish or black slug. They are typically 1/4″ to 1/2″ long, tadpole shaped. […]
Hawthorn: Scale insects Categories: Hawthorn Insects Ornamental trees Ornamentals Last review date: 2026-09-29 06:57 Last edit date: Lecanium scales on twig Photo by: R.S. Byther Biology Several species of scales may be found on hawthorn. In general, scales are approximately 1/16″ to 1/8″ in diameter, dull or shiny, and grayish to dark in color. They […]
Hawthorn: Fire blight Categories: Hawthorn Hawthorn Diseases Ornamental trees Ornamentals Last review date: 2026-05-15 11:49 Last edit date: Fire blight infected leaves Photo by: G.G. Grove Biology Fire blight is a bacterial infection of shoots which enters the plant through blossoms, vigorously growing shoot tips, young leaves, and wounds. Blossom clusters appear blighted. Shoots suddenly […]
Hawthorn: Leaf spot Categories: Hawthorn Hawthorn Diseases Ornamental trees Ornamentals Last review date: 2026-08-28 02:15 Last edit date: Hawthorn leaf spot Photo by: R.S. Byther Biology Leaf spot is a fungal disease which can infect hawthorn, photinia, pear, pyracantha, crabapple, and related species. Initial infections are small reddish-brown to grayish spots on the upper or […]
Hawthorn: Rust Categories: Hawthorn Hawthorn Diseases Ornamental trees Ornamentals Last review date: 2026-08-28 02:15 Last edit date: Rust pustules on underside of serviceberry leaf and on petiole Photo by: R.S. Byther Biology Rust is a fungal disease typically infecting leaves of hawthorn (occasionally also apple and crabapple). It may also be found on green stems […]
Hawthorn: Scab Categories: Hawthorn Hawthorn Diseases Ornamental trees Ornamentals Last review date: 2026-08-28 02:15 Last edit date: Apple scab on leaves and young fruit Photo by: R.S. Byther Biology Scab of hawthorn is caused by the same fungus that causes scab on apple and crabapple. The disease infects during wet weather in the spring and […]
Hawthorn: Spider mites Categories: Hawthorn Hawthorn Insects Ornamental trees Ornamentals Last review date: 2026-05-18 07:12 Last edit date: Spider mites under microscope Photo by: L.K. Tanigoshi Biology Spider mites are tiny, eight-legged and variably colored from yellow or green to red or brown. When viewed through a hand lens, they appear as tiny moving dots. […]