Saturday, February 12, 2011

Lodgepole Pine on Orcas Island

Lodgepole pine on Mount Constitution

Young lodgepole

Lodgepole pines on Orcas Island

Lodgepole pine has a range from the the mountains of Mexico to the Yukon and from the Pacific Coast to Alberta and Colorado. But most impressive is the range of elevation. This is a tree that grows well in very cold temperatures high in the Rocky Mountains. Large tracts of Yellowstone National Park and the high Colorado Rockies are covered by these trees. But the lodgepole is also present at low elevations in western Washington.

Just because the lodgepole can be found over a large range, this is a species adopts very specific traits to the sites where they grow. Hence taking seeds from one site to another to grow lodgepoles often leads to poor tree growth and coastal lodgepoles are particularly limited based on studies on the east side of Vancouver Island by Ying and Liang (1994). They noted even elevations of 500 feet had significant difference in tree health.

I observed stands of lodgepole on Orcas Island last week. The lodgepole pine (Pinus contorta) in the lowlands of western Washington are considered a subspecies called shore pine (Pinus contorta contorta).  The name shore pine is misleading as I find this lodgepole subspecies well away from the water more frequently than near the water. For a time I would see a contorted evergreen growing on rocky ground near the water and think it must be a shore pine but nearly always found the tree to be a Douglas fir. This winter I was on the upper slopes of Mount Constitution on Orcas Island well away from the water at 2,000 feet elevation and suddenly realized that nearly the entire stand of evergreens I was in consisted of lodgepole pine.

Lodgepoles were likely much more common in the past in western Washington when forest fires were more common. Particularly in areas in the Olympic Mountains rain shadow or areas where there are thin soils. Orcas Island straddles the rain shadow and certainly has lots of rocky areas with very thin soils. Balds and prairie areas were formerly much more extensive and fires would have been a much more common occurrence both naturally and from fires set by First Nations peoples. Without fire the larger, taller Douglas fir and western hemlock will shade out lodgepole.

I did note that young lodgepole seems to have an advantage over young Douglas fir. Deer nibble young fir into natural banzai trees, but leave the lodgepole alone giving the lodgepole pines an advantage. 

Lodgepole surrounded by heavily cropped Douglas fir

Stunted Douglas fir

1 comment:

G. Koep said...

I live in the Olympic Mountain Range rain shadow on southern Vancouver Island. Thanks, by the way - we enjoy quite a nice climate here because of that.

I see pine trees all the time on my hikes. They are not as noticeable as the larger Douglas-fir and Western red-cedar, but they are everywhere from the ocean up to the tops of the hills.

Hard to believe the stunted, twisted trees are related to the ones so straight and tall that native people used them for lodge poles.