Mountain Pine Beetle Natural Disaster or Natural Consequence?

1. Mountain Pine BeetleNatural DisasterorNatural Consequence?

2. Presentation Overview • Meet the Mountain Pine Beetle (MPB) • Importance of Lodgepole Pine in BC • Life Cycle of the bug • Green – Red – Gray Attack • Population Dynamics • Pine – Beetle – Fire Ecology • Management Tactics

3. Meet the MPB • MPB - a small beetle, the size of a grain of rice • Range western N.A. (and is now expanding) • MPB is an important part of the ecosystem • but it can have dramatic effects • Preferred host is lodgepole pine

4. Importance of Lodgepole Pine in BC • BC – has a vast amount of lodgepole pine • Some figures: • 95 million ha (hectares) – size of BC • 60 million ha – forested land • 25 million ha – “operational forests” • 15 million ha – lodgepole pine forest (~25% of BC’s forest) • 13.5 million ha – MPB outbreak • 0.2 million ha harvested per year • When the outbreak is finished … • 80% of the mature lodgepole pine in BC will be dead

5. The Outbreak !! Videos – Ministry of Forests Cumulative Damage–of current outbreak (from 1999) After viewing an animation, when you hit the “back” button to return to this presentation you may see a window that asks whether you want to open, save or cancel – select open to return to this slide.

6. Life Cycle • Typical 4 stages of an insect (with complete metamorphosis): • Adult • Egg • Larva • Pupa

7. Adult • Adults emerge from under the bark in late summer • Need to fly! • Female seeks out a suitable host • Larger (older) pine is preferred (kairomones) • Once suitable host is found … pheromones female-perfume & males-cologne (=party time!) • Mating pair then tunnels into the cambial zone • Inoculate tree with blue stain fungus • “No vacancy” pheromone once tree is fully occupied

8. Egg • Parents bore a gallery in the inner bark / cambial region • Gallery is vertical • Eggs are laid alternately along the sides of the gallery

9. Larva • Larva hatch after 1-2 weeks • Larva create feeding tunnels at right angles • Inner bark (phloem) is full of sugar! • Larva overwinter under the bark … • … and continue feeding next spring

10. Pupa • Pupal stage occurs the following year • Takes about 2-4 weeks to change from a larva to an adult

11. Life Cycle Review 4) Next Summer (next generation of adults emerge) 1) Summer (adults emerge & attack) 3) Next Spring (larva continue feeding, then pupate) 2) Over winter (as larva under the bark)

12. Blue Stain Fungus • Ceratocystis spp. (Ophiostoma) • Ascomycetes (not a decay fungus) • Brought in with the beetle • Fungus infects sapwood • Blocks water flow • Reduces ability to ‘pitch out’ beetle • Retains moisture – good for beetle brood • Provides critical nutrition for young adults

13. Green – Red – Gray Attack • In the year a pine tree is attacked (summer) it remains green • The following year it dies … and turns bright red (but beetles are gone) • After that the foliage turns gray and falls off • Only the green attack trees contain beetles

14. Susceptible Stands • Susceptibility increases with • Age (>80 years are at highest risk) • Size (> 25 cm diameter @ breast ht.) • Stand composition (higher % of pine, higher risk) • Stand density (750 – 1,500 trees/ha) • Temperature (lower latitude/elevation, higher risk)

15. Population Dynamics (4 Stages) • 4 Stages: • Endemic – “normal” level – natural thinning agent • Incipient – building phase • Epidemic – outbreak! – stand replacing agent • Collapse (back to endemic) • Factors favoring the outbreak • Abundant food source (Pl forest) • Drought stress (late ’90’s and 2003) • Nice weather for beetle flight (summer) • Mild winters • Collapse Factors • Lack of food • Cold weather • -40C ‘spike’, -30C prolonged, -20C in shoulder season

16. Reminder • This outbreak is the largest in BC recorded history • After it is done … ~80% of the lodgepole pine will be dead • Reasons for outbreak: • Abundance of pine • Mild winters • Warm summers

17. MPB – Fire – Lodgepole Pine • Fire & the MPB play a complex role in regenerating lodgepole pine (video) • you will have the option to download a video from the Canadian Forest Service (CFS) web site; video is about 5 minutes and VERY good • after viewing the video, when you hit the “back” button to return to this presentation, you may see a window that asks whether you want to open, save or cancel – select open to return to this slide • Low intensity fires act as a thinning agent • High intensity fires act as a stand replacing agent • We fight fires … so we now have denser (more stressed) stands AND we have more area with older lodgepole pine than ever before (3 x’s) • Natural fires ~500,000 ha … now ~23,000 ha fire • Remember the MPB likes older, stressed lodgepole pine

18. Management Options – aimed at MPB • Annual Monitoring (aerial/ground surveys, pheromone traps) • Mass Trapping – often with other trtmts(with pheromones, ineffective in epidemic) • “Go after the beetle” • Sanitation Logging – a control tactic(get the green attack before beetle flight) • Spot Treatment – for isolated patches(insecticide (MSMA) or fall & burn, before flight) • Broadcast Fire - mimic nature(with control measures) • Hauling Restrictions – no hauling during beetle flight (less of an issue in vast epidemic) • Salvage Logging – not a control tactic(get the red/gray attacked trees) • Abandon – for out of control epidemic(just “walk away”) • Protective Insecticide – for urban setting(Carbaryl (Sevin) on trunk before flight) • Pheromone Repellant- verbenone, looks promising (“no vacancy” scent) • Trunk Screen - fiberglass wrapped around trunk – urban setting

19. Management – Aimed at Pine • Log most susceptible stands first (80+ yr, 25+ cm dbh, etc.) • Create an age class mosaic within a watershed • Utilize a shorter rotation (harvest) age • Promote mixed species (planting & spacing) • Remove pine from mixed stands (during outbreak) (speed succession) • “Beetle proof” pine stands reduce density <500 sph(light/temp, wind, vigour)

20. Summary • Outbreaks result from an abundant food source and favourable weather (warm summers & mild winters) • In spite of best efforts, outbreaks will occur … they are natural • Best time for action is at the incipient stage • Long term management should focus on lodgepole pine, not the MPB

21. This presentation was brought to by… the Tree Doctor

22. That’s all folks!