- Ambrosia Beetles
- Overview
- a.k.a. pinworms, pinhole beetles
- generalized life cycle
- adults fly in spring/ summer
- semiochemicals
- "attack" windthrow/ logs (kairomones ... alcohol & pinene)
- aggregation pheromones ... mating
- anti-aggregation pheromone
- tunnels into log
- white dust on bark
- tunnels in outer sapwood ($$)
- ambrosia fungus (black staining)
- feed on fungus
- larva remain 'in place', pupate and later emerge out same hole
- biggest economic insect pest on the coast
- losses: $100+ million / yr
- 75% in forest
- 25% in sorting/ storage areas
- premium lmbr → common lmbr
- signs & symptoms
- Trypodendron highlights
- OW in duff
- spring - flight when 3 days >16C (April-May)
- flight
- photopositive
- kairomones
- poor flyers (4-6 ft ht)
- attracted to logs felled fall/ early winter
- needs bark on log
- life cycle stuff
- female ♀ tests log, aggregation pheromone (lineatin)
- female tunnels & male cleans
- may have 2nd flight in July
- egg - adult in ~ 10 weeks
- emerging adults are photonegative, NOT attracted to semiochemicals
- OW in duff
-
- 2 species: G. sulcatus & G. retusus
- prolonged spring (summer) flight, (May-June ... July)
- less picky about host material
- down time as little as 2 weeks & up to 3 years
- will attack material without bark ... green lmbr
- male ♂ tests log, aggregation pheromone (sulcatol, retusol)
- entire life cycle within log, except to find new material
- Management
- Avoid Attack
- hot logging
- logs felled fall & winter, move out by March
- Tryp. has a major flight in Apr.-May, need to avoid
- Gnath. attacks 'any age' and flys over spring/summer months
- rapid turnover of logs in DLS
- FIFO principle, esp. valuable logs
- Repel Attack
- water misting
- sprinklers - fine mist
- poor flyers
- no fly in 'rain' or <16C
- mist cools the air temp
- mist 'waters down' semiochemicals
- but
- need constant watering (weekend example)
- drainage of DLS
- maintenance
- corrosion if salt water
- damage from normal DLS operations
- repellants
- terpentine & pine oil
- verbenone (anti-aggregation pheromone)
- Trapping
- purpose
- monitor - 30-40 traps (at new site)
- reduce/"exclude" pop'n @ DLS - 120-240 traps ... perimeter barrier
- method
- funnel traps
- chemicals
- pheromone (lineatin, sulcatol and/or retusol)
- pinene
- alcohol :o)
- timing
- spring - 85:15 for Tryp:Gnath
- summer- 50:50 for Tryp:Gnath
- trap logs
- to attract those that get past perimeter
- use low grade logs of right "vintage"
- can lace with attractants
- and add insecticides
- problems
- process logs when beetles inside (10 wk window)
- logs vary in attractiveness
- hard to estimate pop'n - not good for monitoring
