This genus of small, brightly colored moths have larvae who bore into the bark of deciduous trees. The linden bark borer moth is a native of Europe. It was first reported in North America from specimens collected in New York City in 1928 (Klots, 1942). Reports in additional states include New Jersey, Connecticut, Vermont, and near Boston, Massachusetts. This species has also been reported in parts of Canada. Larvae of the linden bark borer moth feed in the bark of European linden (Tilia x europea). Larvae excrete rusty colored frass as they feed. Pupation is reported to occur in the early spring, once larvae reach approximately 6 mm. in length. Reports indicate that adults emerge and may be seen flying approximately from May to August. However, adults may fly in early June in Massachusetts for 7 to 10 days (Robert Childs, UMass Extension). In Canada, abundant numbers of adults have been reported, indicating that clouds of hundreds or thousands of the adult moths can be seen flying during the day around infested trees. A single generation is reported, however little about the biology of this species is known. The bark of its host becomes honeycombed by the feeding larvae - and they can cause this damage from ground level on the trunk through high in the crown of the tree (Majka, 2005).
Larvae feed in the bark of European lindens, primarily, and cause damage that makes the inner bark look like a honeycomb. In some reports, even the outer bark is severely damaged to the point where it can be crumbled by hand. Long and short-term impacts of this insect on its host need to be investigated (Majka, 2005). Further study to understand the extent of the impact of this insect on its hosts in Massachusetts is also needed in order to confirm pest status.
Look for reddish, fine sawdust in lower bark furrows, especially in May–June on European linden.
Information about cultural management options for the linden bark borer moth is currently unavailable. Further study is necessary.
Information about natural enemies and biological control options for the linden bark borer moth is currently unavailable. Further study is necessary.
Abamectin (NL) (Labeled for “Lepidopterous insects” and other borers.)
Acephate (larvae) (NL) (Labeled for “Lepidopterous larvae” and other borers.)
Azadirachtin (NL) (Labeled for “borers”.)
Chlorantraniliprole (larvae) (NL) (Labeled for “Lepidopterous larvae” and other borers.)
Chlorpyrifos (N) (Labeled for “Lepidopterous larvae” and other borers.)
Cyantraniliprole (NL) (Labeled for “caterpillars, larvae” and other borers.)
Imidacloprid (L) (Labeled for “larvae” and other borers.)
Neem oil (NL) (Labeled for “caterpillars” and "borers".)
Permethrin (L) (Labeled for “borers”, including those of other lepidopterous species.)
Spinosad (NL) (Labeled for “Lepidopterous larvae” and “borers”.)
Tebufenozide (larvae) (NL) (Labeled for “caterpillars” and “Lepidopterous larvae”.)
When used in a nursery setting, chlorpyrifos is for quarantine use only.
Active ingredients that may be applied systemically include: abamectin (injection), acephate (injection), azadirachtin (injection, soil drench), chlorantraniliprole (soil drench), cyantraniliprole (soil drench, soil injection), imidacloprid (soil drench), and neem oil (soil drench).
Make insecticide applications after bloom to protect pollinators. Applications at times of the day and temperatures when pollinators are less likely to be active can also reduce the risk of impacting their populations.
Note: Beginning July 1, 2022, neonicotinoid insecticides are classified as state restricted use for use on tree and shrub insect pests in Massachusetts. For more information, visit the MA Department of Agricultural Resources Pesticide Program.