Elm: Aphids categories: Elm Elm Insects Ornamental trees Ornamentals revision date: 2024-04-08 11:46 Elm woolly aphidPhoto by: A.L. Antonelli Biology Aphids are soft-bodied, pear-shaped insects that feed on the leaves. They are yellowish to green in color and approximately 1/16″ long. Aphids often produce honeydew, a sweet, sticky substance which can develop a dark growth […]
Elm: Bark beetles categories: Elm Elm Insects Ornamentals revision date: 2022-11-22 02:27 Bark beetle larval galleriesPhoto by: A.L. Antonelli Biology Elm bark beetles are about 1/8″ long and may be shiny brown or black. Adults, larvae, or pupae overwinter under bark. Adult beetles emerge in the spring (around May), leaving tiny “shotholes” in the bark. […]
Elm: Carpenterworm categories: Elm Elm Insects Ornamental trees Ornamentals revision date: 2022-11-22 02:15 Carpenterworm larval minePhoto by: Unknown Biology Carpenterworms are the larvae of a mottled gray and black moth. The caterpillars are white to pinkish-red with a dark head and 1″ to 3″ long when mature. They bore in the trunk and main branches […]
Elm: Elm leaf beetle categories: Elm Elm Insects Ornamental trees Ornamentals revision date: 2023-04-04 12:00 Elm leaf beetlesPhoto by: Unknown Biology Elm leaf beetles feed on the leaves both as larvae and as adults. The larvae appear in late spring (typically May-June) from eggs laid by overwintering adults. The 1/4″ larvae are greenish or yellow […]
Elm: Elm leafminer categories: Elm Elm Insects Ornamental trees Ornamentals revision date: 2022-11-22 01:41 Elm leafminer damagePhoto by: J. O’Brien Biology Elm leafminers feed by removing green tissue from between upper and lower surfaces of the leaves. Symptoms of feeding by the yellowish or green larvae include large brown to gray brown blotches on the […]
Elm: European elm scale categories: Elm Elm Insects Ornamental trees Ornamentals revision date: 2023-04-04 12:00 European elm scalesPhoto by: A.L. Antonelli Biology The European elm scale is a reddish-brown to purplish scale surrounded by a conspicuous fringe of white, waxy material. They sometimes resemble mealybugs. The mature females are about 1/8″ in diameter. The crawlers […]
Elm: Bacterial wetwood (Slime flux) categories: Elm Elm Diseases Ornamental trees Ornamentals revision date: 2022-11-22 01:14 Elm bacterial wetwood (slime flux)Photo by: R.S. Byther Biology Wetwood or slime flux is a bacterial infection common in elm and poplar. The infection causes production of large amounts of moisture in the wood of trunks or large branches. […]
Elm: Dutch elm disease categories: Elm Elm Diseases Ornamental trees Ornamentals revision date: 2022-11-22 01:10 Dutch elm diseasePhoto by: C.R. Foss Biology Dutch elm disease is a fungal infection transmitted by elm bark beetles. Bark beetles carry disease spores on their bodies and infect trees when they feed. Leaves above the infection site turn yellow […]
Elm: Nectria canker categories: Elm Elm Diseases Ornamental trees Ornamentals revision date: 2022-11-22 12:56 Nectria canker fruiting bodies on branchPhoto by: R.S. Byther Biology Nectria canker is a fungal disease often found on twigs and branches that have been weakened by drought, frost damage, insect damage, or other diseases. Cankers are initially distinguished by discolored […]
Elm: Spiny elm caterpillar categories: Elm Elm Insects Ornamental trees Ornamentals revision date: 2023-12-02 09:17 Spiny elm caterpillarPhoto by: S.J. Collman Biology The spiny elm caterpillar is the larval stage of the mourningcloak butterfly. The adult is approximately 2 1/2″ across, with purplish-brown to black wings bordered by a creamy yellow stripe and a row […]