Insects & Disease
We provide technical assistance and training to private landowners and forest managers, designed to minimize insect and disease risk.
Our focus is on prevention and suppression of damaging insects, diseases, and weeds before and during outbreaks. We promote restoration of tree species most suited to the soils and environment in order to grow long-lived, productive and healthy forests.
Prevention is the best means to protect trees. Treatments focused on prevention result in reduction of tree mortality; thinning dense stands, applying preventative chemical barriers, pruning and favoring existing tree species most resistant to forest pests are good examples. Pest surveys and monitoring can prevent a pest from increasing to damaging levels and reduce tree mortality, when early detection is followed by a rapid response.
The IDL Forest Health staff cooperate with other state and federal agencies to complete several annual pest detection and monitoring surveys.
- Aerial detection surveys locate, identify, and map insect damage agents and the impacted tree species across most forested lands in Idaho.
- Monitoring surveys for the native Douglas-fir tussock moth provides predictive data of the next cyclic outbreak and informs management decisions to control the pest.
- Pheromone trapping surveys for the European and Asian gypsy moths detect incipient populations. Early detection of non-native pests increases the probability that eradication efforts will be effective and prevent widespread, long-term damage and mortality to urban and rural forests.
- 2014 Forest Health Highlights (pdf - 4 MB)
- 2015 Idaho aerial detection survey map (pdf)
- Root diseases in the Inland Northwest (pdf)
- Are your trees at risk? Bark beetle brochure (pdf)
- Bark beetle mitigation projects in eastern Idaho (pdf)
- Forest Health highlights by state
- Field guide to diseases and insect pests of northern & central Rocky Mountain conifers (pdf - 7 MB)
Douglas Fir Tussock Moth
- 2016 North Idaho Douglas-fir tussock moth pheromone trapping report (pdf)
- Douglas-fir tussock moth management guide (pdf)
- Douglas-fir tussock moth leaflet (pdf)
- Forest Insect & Disease leaflet (pdf)