**Ambrosia Beetle (Xylosandrus)**

New Jersey notable species: Black stem borer (Xylosandrus germanus),granulate (Asian) borer (Xyleborus crassiusculus)
Small, reddish brown to black, cylindrical beetles from 1/8 – 3/16 inches long
Entrance and exit holes from the beetle are about 1mm in diameter
Increases plants’ risk for infection by opportunistic pathogens (i.e.Fusarium spp.)
Two generations per year
Overwinter in tree galleries (tunnels they create inside of the trees)
First attacks occur from April to June, but peak adult emergence, flights,and egg-laying occur during the first two weeks of May
Sawdust and frass pushed out from the holes resemble toothpicks
- Once these are observed, it is too late to apply protective insecticides
Can cause increased sap production, branch wilting, dieback, barkcracking, and wood staining
Redbud flower bloom is a useful PPI
Host plants: Deciduous, thin-barked species
- Dogwood, honey locust, magnolia, maple, redbud, Japanese snowbell

Avoid transporting infested plants
Reduce plant stress
- Provide appropriate soil conditions and sufficient space for root growth
- Protect trees from injury
- Avoid excessive pruning, over- and under watering
- Trees under anaerobic stress are more likely to be attacked
Ethanol baited traps
- Use to scout for infestations and time spraying treatments
Watch for successive 70F days = triggers flight

Contact insecticides:
- Pyrethroids [3]: permethrin, bifenthrin
  - Spray on lower stems before peak beetle flight
Systemic insecticides:
- Not effective because beetles feed on fungus in trees, NOT the tree tissues themselves.
Considerations:
- Will harm beneficial and non-target species.