Boisea (Leptocoris) trivittata

Adult and immature boxelder bugs. Photo: Carol Simisky
Scientific Name: 
Boisea (Leptocoris) trivittata
Common Name: 
Boxelder Bug
Growing Degree Days (GDD's): 
None available at this time.
Host Plant(s) Common Name (Scientific Name): 
Boxelder (Acer negundo)
Fruit of apple or plum, occasionally.
Silver maple (Acer saccharinum)
Insect Description: 

This insect is known from eastern Canada throughout the eastern United States. Mostly a pest when adults try to enter homes to overwinter. They will gather in groups on the south sides of trees, buildings, and rock faces exposed to the sun. After they gather in large amounts, they will fly together to homes or buildings, searching for a place to overwinter. In the spring, they leave their overwintering shelter and seek out expanding boxelder buds, where they will lay eggs between late-April and early-May in the cracks and crevices of boxelder bark or surrounding sheltered areas. Eggs change in color from yellow to red as they mature. Nymphs are red when they emerge from hatched eggs and feed on fallen boxelder seeds. Up to two generations may occur per year, depending on local temperatures.

Damage to Host: 

Often a nuisance household pest in the fall as adults seek shelter. (Boxelder bugs do not cause structural damage in buildings.) Be sure all window screens fit snugly and close any gaps/openings that would allow entry into the home. Foliage and twigs of female boxelder (Acer negundo) may be impacted slightly. May cause foliar distortion, bronzing, or stippling. Generally not a threatening pest to boxelder. Feeds on seeds of female boxelder; remove female boxelder trees, if necessary, to reduce populations seeking overwintering shelters. Adults fly long distances, so removing trees may not be entirely effective as additional hosts on neighboring properties may be located close enough to provide a population looking to overwinter.

Monitoring: 

If found inside structures such as homes of garages, investigate to find the possible point of entry.

Cultural Management: 

Be sure all window screens fit snugly and close any gaps/openings that would allow entry into the home. Remove from indoor locations using a vacuum. Empty the vacuum after each use. Chemical management inside the home for boxelder bug is not recommended or necessary.

Natural Enemies & Biological Control: 

None reported.

Chemical Management: 

Acephate (NL)

Azadirachtin (NL)

Carbaryl (L)

Chlorpyrifos (N)

Cyfluthrin (NL)

Cypermethrin (NL)

Deltamethrin (L)

Gamma-cyhalothrin (L)

Horticultural oil (L)

Lambda-cyhalothrin (L)

Permethrin (L)

Pyrethrins (L)

Tau-fluvalinate (NL)

Zeta-cypermethrin (L)

Notes: 

Chemical management of boxelder bugs on host trees is not necessary to protect the overall health of the host plant, since this insect is often not very damaging to its host. It may be considered on landscape specimens that are attracting boxelder bugs, which in the fall may seek overwintering shelters in nearby homes, if that is a problem. However, chemical management for this insect is often not necessary.

Active ingredients that may be applied systemically include: Acephate (injection) and azadirachtin (injection, 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.

Read and follow all label instructions for safety and proper use. If this guide contradicts language on the label, follow the most up-to-date instructions on the product label. Always confirm that the site you wish to treat and the pest you wish to manage are on the label before using any pesticide. Read the full disclaimer. Active ingredients labeled "L" indicate some products containing the active ingredient are labeled for landscape uses on trees or shrubs. Active ingredients labeled "N" indicate some products containing the active ingredient are labeled for use in nurseries. Always confirm allowable uses on product labels. This active ingredient list is based on what was registered for use in Massachusetts at the time of publication. This information changes rapidly and may not be up to date. If you are viewing this information from another state, check with your local Extension Service and State Pesticide Program for local uses and regulations. Active ingredient lists were last updated: January 2024. To check current product registrations in Massachusetts, please visit: https://www.mass.gov/pesticide-product-registration .