Part 2: Bark beetles threatening more than just lodgepole pines
This article is the second of a two part series on the book "The Insatiable Bark Beetle" by Dr. Reese Halter. The first article covered the grand sweep of our rapidly warming forests and the attacking strategies of the bark beetles. This second article gives a taste of Dr. Halter's tours of several magnificent forest types and the dire future awaiting them if we continue to overheat our planet.
For a few years I've been reading a lot -- and writing occasionally -- about the mountain pine beetle's epic attack on BC's lodgepole pines. All this time I've been bothered by the lack of discussion about: "what comes next?"
The media and politicians talk as if BC's epic beetle kill is a one-time event that is now winding down. But how can that be if the climate continues to warm rapidly, humans are doing nothing effective to slow it down, and the bugs certainly aren't going away? Clearly there is more to this story that isn't getting reported or discussed.
Fortunately I finally stumbled upon this tiny gem of a book -- "The Insatiable Bark Beetle" by Dr. Reese Halter. Dr. Halter spent months reading "a couple thousand scientific papers and several dozen books." He compiles all that into an extremely readable and engaging series of chapters devoted to many different kinds of conifers in harm's way:
- Lodgepole Pines
- Spruce Forests
- The Piñon Pines
- The Whitebark and Limber Pines
- The Bristlecone Pines
I have read this book three times now, amazed at what I'm learning about our magnificent forests and the threats our native bark beetles pose in a rapidly warming world. Finally someone has laid out for the general public the larger picture of "what comes next?"
Here are a few insights and excerpts from the book's later chapters on specific tree species.
The Lodgepole Pines
The shocking tale of how the tiny mountain pine beetles devoured half of BC's lodgepole pine forests in just the last decade is fairly well known. (see: Half of BC pines dead from fossil fuel pollution. Is it over?)
Dr. Halter tells that story briefly and goes on to make it clear that it is much larger than just in BC:
Mountain pine beetles have also been on an epic all-you-can-east smorgasbord in the US, across eastern Washington, Idaho, Montana, Wyoming, Colorado and South Dakota… mortality rates in excess of 90 per cent, as many smaller-stemmed trees have also been killed from intense infestations.
What is much less well known is that the remaining BC lodgepole pine forests in our colder northeast are next on the menu as the climate warms. Even worse, they lack a critical "terpenoid" resin defense mechanism because they have never faced mountain pine beetles before. Global warming is now allowing the bark beetles access to these "naïve" and unprepared forests.
Any subsequent temperature rise of between 1 and 2C will be endgame for many lodgepole pine forests; the species would likely survive in only 17 per cent of its current range.
And the wholesale destruction doesn't stop with lodgepole pines. As this chapter makes gruesomely clear, when lodgepoles are in short supply the mountain pine beetles are happy to attack and devour:
- western white pine
- ponderosa pine
- whitebark pine
- limber pine
- eastern white pine
- pitch pine
- red pine
- jack pine
- true firs
As we warm the planet, vast new landscapes are becoming accessible to these insatiable bark beetles:
There is every reason to believe that jack pines, red pines and eastern white pines along the lake states in the northeastern United States will, with rising temperatures, also face mountain pine beetles incursions.
This chapter tells the story of six rugged and long-living species of spruce that have thrived where the climate has been cold enough to prevent the Spruce Bark Beetle (Dendroctonus rufipennis) from reaching dangerous levels.