Re: ALB in Hawaii?
Here's some good info straight off of the USDA site:
Control zone: Remove or chemically treat all ALB host material within a minimum 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.
