- Forest Health
- What is a healthy forest?
- "normal" biological functions
- photosynthesis & respiration
- growth
- carbon cycling
- energy cycling
- nutrient cycling
- etc.
- resilient to short term stress
- able to adapt to long term changes (climate)
- * satisfies mgmt objectives
- habitat for fish & wildlife
- wilderness
- biodiversity
- sequester carbon
- water quality
- recreation & aesthetics
- products (timber, food, greenery)
- 3 levels of health
- individual tree
- forest stand - majority healthy - some sick, individuals die - new trees grow
- forest watershed(s)
- biological legacies
- snags & wildlife trees
- consider disease
- landscape pattern (from disturbance) over time
- fire, insects, disease, climatic events
- harvesting patterns should "mimic"
- ecological processes
- energy capture & flow thru' the system ("happy healthy forest")
- hydrologic (e.g. MPB)
- Damaging Agents
- Fire
- Insects
- Disease
- Abiotic
- Scale of Disturbance
- low (endemic) level
- "natural"
- (if early) acts as a thinning agent
- sporatic mortality provides diversity (structure, age, species)
- can speed succession (change of species)
- high (epidemic) level
- unusually high level
- short term (yes for bugs, maybe not for disease)
- = major disturbance event
- stand replacement (i.e. kill existing and begin anew)
- or "just a major loss"
- introduced pests are a special case
- Introduced Pests
- native trees have little/no defence against introduced pests
- Often "wipes out" the native species
- examples
- Why we even care
- look back at mgmt objectives
- Forest Health Mgmt
- we manage forest to minimize/ prevent negative impacts
- how
- consider forest health triangle
- damaging agent (insect, disease or fire)
- host tree
- environment
- essentially target one of the above
- "attack" the agent (=sanitation, stumping)
- manage the host (tree) - species & vigour
- alter the environment (mainly in a nursery)
- short term (a.k.a. launch an offensive, attack the agent of mass destruction)
- stumping for root rots
- minimize scarring to minimize decay
- pruning for stem rusts
- trapping for insects
- sanitation - removed diseased/ infested
- pesticides - mainly defoliators (Btk & NPV)
- long term (grow a happy, healthy, resilient forest)
- promote species mix within stand
- many diseases/insects are "host specific"
- also consider potential climate change at planting - considers long term resilience
- a diverse forest stand is more resilient
- silviculture - maintain vigour
- fertilization
- thinning
- a vigourous stand is more resilient
- harvesting "mimics" natural disturbance patterns
- breaks-up the landscape
- mosaic of different aged forests
- "natural"
- many diseases/insects are age class specific
- a diverse landscape is more resilient
- The Big Guns
- Root Disease
- agents: DRL, DRA, DRT, (DRN), DRB, DRR
- damage: what & when
- signs & symptoms
- biology of the beast
- Root Rots (DRL, DRA, DRT)
- harvest/ regen
- alternate species (ecol. suited)
- stumping ($$, prod., site factors)
- avoidance? (marking imp., planting too)
- partial harvest??
- FG/ JS
- infection level
- other thoughts
- bridge tree
- flare-up
- pop-up spacing ($, site deg.)
- brushing
- DRB, DRR & DRN?
- Dwarf Mistletoe
- agents: DMP, DMH, DML, DMF
- damage: what & when
- signs & symptoms
- biology of the beast
- harvest/ regen
- residuals (proximity/ adjacency)
- mixed spp ... always a good idea
- FG/ JS
- Stem Rusts (Cankers)
- damage: what & when
- signs & symptoms
- biology of the beast
- Native: DSC, DSS, DSG
- infection level?
- timing?
- life of stand
- when to survey
- when to space (season, age of stand)
- sanitation
- density?
- delay?
- if high infection
- but not too long (up to 15 or 20yr)
- DSB
- hazard rating
- broad geographic
- site specific
- pruning
- tree breeding
- density?
- DSA
- damage: what & when
- harvest/ regen?
- FG/ JS?
