Life As a Lodgepole
Lodgepole pines, pinus contorta, are named for their arrow-straight trunks, a species prized by native peoples for teepee poles. A common conifer of the Rocky Mountains, lodgepoles inhabit the middle zone of the mountains, generally above the foothills, but below the barren ridgetops and towering peaks on the crest of our nation’s greatest mountain range.
A species whose lifecycle is bound closely to fire, crowded, dehydrated stands of lodgepoles whose moisture content sometimes approximates that of kiln-dried lumber are often first to ignite in a lightening storm. Dense stands are normally devoid of lower branches on their trunks, creating spectacular infernos as flames race through the forest crown. After the fire, lodgepoles have a unique mechanism for repopulating their seared environment. The cones of this species open only when temperatures exceed 113 degrees (F), releasing seeds during a forest fire that will germinate in the scorched earth with the coming of spring. Lodgepoles produce cones every year that accumulate on the ground until a fire provides sufficient heat to open them. According to the U. S. Forest Service, viable seeds have been retrieved from cones 80 years old.
In 1988, wildfires seared vast portions of the lodgepole landscape in and around Yellowstone National Park. On a recent hike, I observed several areas burned in the ’88 fires. Some of the “new” trees, now in their third decade, had achieved heights of some ten feet or more. These were the saplings inhabiting good soil. Some slopes, however, were populated by stunted lodgepoles who had yet to press more than three feet above the rocky, poor soil. It’s easy to assume that in a given region, trees of the same size are roughly the same age. But obviously not. Very localized conditions may greatly favor a stand of trees on a fertile slope over its neighbors less than a quarter-mile away. Such is the life of a lodgepole.