Asian Longhorned Beetle Control Strategy

Asian Longhorned Beetle Control Strategy


Host Material Removal
Chemical Control
Data Collection

The control strategy provides a means to significantly reduce ALB populations by targeting the area into which the pest is most likely to naturally disperse from an outbreak site.


Infested trees: Remove ALB-infested host material. Presence of oviposition sites or exit holes indicates infestation.

Control zone: Remove or chemically treat all ALB host material up to ½ mile radius of infested hosts.

Hosts: For control purposes, hosts include Acer spp., Aesculus spp., Albizia julibrissan, Betula spp, Celtis spp, Cercidiphyllum spp., Fraxinus, spp., Platanus spp., Populus spp., Salix spp., Sorbus spp., and Ulmus spp.

Rationale for minimum radius:

  • Estimated distance of natural spread/year:
    • China: maximum distance in mark-recapture study - 4600 ft in 3 weeks,
    • Chicago: 2 years data; measured distance from 666 trees with oviposition sites only to the nearest tree with exit hole: 80% of trees with oviposition site only are within 330 ft (1/16 mile) of a tree with an exit hole; 94% within 660 ft (1/8 mile); 99% within 1320 ft (1/4 mile); 99.7% within 1980 ft (3/8 mile); Trees with both oviposition sites and exit holes are excluded from the analysis.
  • Flight ability: China: maximum distance of single observed flight - 1200 ft.

Managers may conduct control activities beyond the minimum depending upon the detection data and the degree of infestation. For example, where there is a large established core with several satellite detections beyond the minimum radius, a manager may want to conduct control activities in the area between the core and the satellite detections.

Any decision to reduce the scope of control actions will be made in consultation with the project director and cooperators.

The decision between removing and chemically treating host trees depends upon specific characteristics of the site or area. Onsite managers in conjunction with the program director and cooperators will determine the most appropriate activity based on social, biological, environmental, and economic concerns. Considerations:

  • Total host removal and/or chemical treatment within a ½ mile radius would encompass an area where a large percentage of the beetles would disperse, but a low percentage will likely disperse beyond this distance. An effective detection program is essential both inside and outside the control zone.
  • Host removal removes immature life stages eliminating potential adult beetle dispersal. Host removal is recommended in near proximity of an infested tree because of the likelihood of infestation.
  • Removal during adult emergence and flight season may result in adults dispersing during the process. A bark spray prior to removal is warranted where public and/or environmental health would not be impacted.
  • Chemical treatment will need to remain active through a minimum three emergence seasons to be effective and several applications will be required to ensure effective coverage. Chemical treatment is expected to remove a high percentage of emerging adults as they feed on twigs and leaves prior to mating and dispersal. Mated female adults are susceptible to treated trees as they prepare oviposition sites. Additionally, young larvae burrowing into the tree are also exposed to the chemical.
  • As long as active populations exist in an area, chemical treatments may need to be applied on an annual basis.
  • When using chemical treatments, managers should expect to continue to discover exit holes and/or oviposition sites on treated trees. The chemical treatment is not believed to be effective against large larvae already present in the tree at the time of treatment. Also, some holes/sites may not have been discovered during previous surveys. These newly discovered trees with exit holes and/or oviposition sites should be removed and the control zone be adjusted accordingly. Because of this possibility, tree owners should be informed that their chemically treated tree is less likely to become infested but that the tree may have to be removed in the future if evidence of the beetle is discovered.
  • The cost of removing and replanting a fixed number of trees may equal or exceed chemically treating the same number of trees over a three year period.


It is recommended that the roots of host material be removed to a minimum of 9 inches below ground level. Any aboveground roots of a half inch or more in diameter should also be removed.

Host material should be chipped or burned. Chipped material must be no larger than 1 inch in two dimensions. Host material that is not chipped may be moved to an approved burning site with proper safeguards: vehicles must be tarped or covered to prevent spillage, an emergency spill plan with contact numbers must be carried by the driver, and host material may be held no longer than 24 hours at the burn site prior to burning.

Chemical control

All pesticides should be used according to their label instructions.

1. Soil or trunk injection of insecticides:
Imidacloprid, a chemical with systemic properties and low mammalian toxicity, has been found to be effective against adult ALB as it feeds on small twigs, the female when depositing eggs, and young larvae. This insecticide is formulated for soil and trunk applications from a number of sources. The contractor/applicator and Contracting Officer's Representative (COR) must have all pesticide and 2(ee) labels (if required by the state) at all times during treatment. Label instructions for application must be strictly adhered to as well as all environmental and safety requirements. Proper spill cleanup material must be on site at all times. Treatments are typically made in early spring, in order to allow the insecticide to be taken up and distributed throughout the tree so as to be most effective during the ALB emergence and flight period. Soil treatments can take up to 3 months before sufficient levels are observed in target plant tissues.

2. General pesticide use:

When applying pesticides, phytotoxicity (damage to the target plant) can occur and should be checked on a limited number (1-3 plants per species) of specimens before treating large numbers of trees. The various species can react differently to the pesticide.

Before using any pesticide, always read the entire label and follow all instructions. Make sure the material is registered for your specific use in the area where you plan to treat - in some cases exemptions may be needed before using a product in ALB programs. Make sure all human and animal safety guidelines are strictly followed. Make sure all environmental guidelines are strictly followed and adhere to restrictions regarding the use of insecticides near wetlands and bodies of water. Adhere to state and local requirements. Dispose of any empty containers as per label instructions.

Data collection

1. When ALB host material is treated the following data will be recorded:

  1. Date and time of treatment.
  2. Type of treatment (Mauget, pressurized trunk injection, soil injection, bark spray).
  3. Type and amount of chemical applied.
  4. Location of host material, street address, or GPS coordinates.
  5. Host Species.
  6. DBH of host species.
  7. Tree type (private, street, or park). If private ownership, a release will be obtained, and the name, address, and phone number of the owner will be documented.
  8. Tree location on property.
  9. Contracting company and applicator conducting the treatment.
  10. Work order number.
  11. Weather conditions.
  12. Name of inspector supervising treatment.


2. When ALB host material is removed the following data will be recorded:

  1. Date of removal.
  2. Date(s) of chemical treatment, if applicable.
  3. If tree is infested or high risk.
  4. If infested, damage to tree in regards to number of egg sites and exit holes.
  5. Location of host material, street address, or GPS coordinates.
  6. Host Species.
  7. DBH of host species.
  8. Tree type (private, street, or park). If private ownership, a release will be obtained, and the name, address, and phone number of the owner will be documented.
  9. Tree location on property.
  10. Hazardous conditions at the location.
  11. Contractor conducting the removal.