Forest Entomology Introduction

Forest Entomology Introduction
- History - stages
  - Individual Outbreaks (impact/loss recognized)
  - Taxonomy & Life Cycles - 1800's (study "the individual")
  - Population change due to "a single factor" - 1880-1950 (abiotic vs. biotic vs. pop'n density)
  - Ecological Interactions - 1950-80 (recognition of "web of relations")
  - Population Modeling - present (mathematical models for outbreaks)
- Forest Health
  - 2 Viewpoints
    - Ecosystem (no social values imposed; outbreaks are natural)
    - Utilitarian (mgmt objectives)
  - What is a healthy forest?
    - 'normal' biol. function
    - resilient to short term stress
    - able to adapt to long term change
    - (may) depend on objectives/ viewpoint (as above)
    - provides 'goods & services'
  - 3 Levels
    - individual tree
      - original concept
      - still applies to urban forestry
    - forest stand
      - majority healthy (but some not), most die of "old age", not due to pest outbreak
      - "classic timber forestry"
    - forest ecosystem
      - considers all parts (plants, animals, fungus, etc.)
      - 'functioning' - energy cature and flow, hydrology, carbon, nutrient cycling
      - broader thinking ... holistic: "trees are part of the whole forest"
- What is a PEST?
  - depends on impact on mgmt objectives & forest values
  - it ain't the 'critter itself' ... it's the level of damage
  - said another way "an insect becomes a pest when the damage it causes interferes with mgmt objectives
- Integrated Pest Mgmt (IPM)
  - approach
    - uses all available options
    - as needed vs. "calendar spray" for prevention
    - 3 E's
      - effective
      - economic
      - environmetally safe
  - Steps
    - 1) Correct ID of pest
    - 2) Monitor pop'n level and assoc. injury level
    - 3) Consider Options
      - cultural
        
        how crop is grown
        
        species choice
        
        fallow
        
        density mgmt
        
        harvest age and patterns
        
        nursery: water and fertlizer mgmt
      - mechanical
        
        directed at the pest
        
        traps
        
        screens
      - biological
        
        predators
        
        parasites
        
        pathogens
      - chemical
        
        pesticides
        
        semiochemicals (pheromones & allomones)
      - host resistance
        
        use (breed for) resistant stock
        
        antibiosis
        
        tolerance
        
        preference/ non-preference
      - regulatory
        
        to prevent entry/ establishment of "alien" pest
        
        or to eradicate/ suppress pop'n
        
        legislation (regulations with penalties)
    - 4) Implement treatment strategy
    - 5) Evaluate results (feedback to improve for next time)
- Forest Insect Pest Mgmt
  - managing forestland and (possibly) applying treatments to minimize/ prevent pest damage
  - long term - maintain healthy forest
    - harvesting mimic natural disturbance patterns
    - silviculture - maintain thrifty/ resilient stands (species choice, dtand density)
    - sounds like 'good forest mgmt' doesn't it?
  - short term - action to deal with outbreak
    - monitoring pop'n/ damage
    - trapping
    - pesticides
    - bio-controls
    - sanitation
    - sounds like IPM doesn't it?
- Why do we even care? (Impact of Outbreaks)
  - Economics
    - AAC - delay establishment, ↓ stocking, ↓ growth, mortality
    - value $$ - deformities, species (Ss), product (stain, holes)
    - cost of mgmt - disrupts plans, direct costs
  - Other Values
    - wildlife habitat
    - recreation / aesthetics
    - hydrology / water quality
  - All tree parts affected
    - seeds & cones
    - seedlings - cutworms and root weevils
    - saplings & poles - terminal weevils, aphids, shoot tip moths, defol.
    - mature - defol., bark beetles, wood borers
    - dead & down - wood borers
  - Ecology
    - recycling / decomposition
    - stand replacement vs. stand thinning
    - diversity in species, age & structure
    - fire
      - dead trees are a fire hazard
      - fire suppression & MPB
    - complexes & predisposition
      - defol & bark beetles
      - root disease & bark beetles
    - stand development
      - forest-range (PyFd) - tussock moth
      - convert Pl to Sx stand - MPB
      - delay Ss growth/ establishment - terminal weevil