The Whitebark Pine (Pinus albicaulis) is a keystone species in the sub-alpine forests from western Wyoming north to central British Columbia and Alberta. It can also be found at the timberline in the Cascades (think: BC down to the Sierra Nevada) and some mountains between the Cascades and the Rockies.
The Whitebark Pine has been historically ignored by foresters and ecologists, but that changed in the 1980s when researchers realized its importance to the ecosystem as both a moderator of hydrology and a critical food source for fauna.
Hydrology. Whitebark Pine has a broad crown that creates a lot of shade, much more shade than the other species with which is grows. Without the shade provided by the Whitebark Pine, snow melts faster. This alters regional hydrology by increasing spring floods and late summer drought.
Food Source. The Whitebark Pine is also a critical wildlife food source. Bears will eat the seeds of the Whitebark Pine instead of salmon because they are so nutritious! In addition, the Whitebark Pine has a special relationship with the Clark’s Nutcracker. The Clark’s Nutcracker feeds on these seeds and caches them, dispersing them to other mountains by burying the seeds to eat later. In fact, without the Clark’s Nutcracker, Whitebark Pine wouldn’t be able to reproduce – its seeds can’t grow in the shade of their parents and only grown on burned and disturbed sites with plenty of sun.
To encourage the Clark’s Nutcracker to eat and disperse its seeds, the cones of Whitebark Pine face upwards and aren’t open so only the Nutcrackers can get to them. The Nutcrackers then store up to 200 seeds in their sublingual pouches (the only bird known to have one!) as they forage and cache.
Threats. Unfortunately, this keystone tree faces numerous threats, including from pine blister rust, the mountain pine beetle, climate change, and changes in fire regime. Pine blister rust originated from Asia by way of the American nursery trade with Europe. The rust has a few alternate hosts, like Ribes species, that help it stay in the ecosystem. Newly infected plants tend to develop red-brown branches until the entire tree just dies. The good news is that a small percentage of plants have some natural, genetic resistance to the rust. Conservationists and the park service are working to propagate Whitebark Pine trees from those resistant plants.
How do you identify Whitebark Pine? This pine is in the “white pine” group, so it has needles in fascicles (i.e., bundles) of 5s. These needles are small, only 1.5 to 3 inches long. The cones, often standing upright, which is strange for pine, and closed up are 2 to 3 inches long. The bark is also a distinctive, gray-white color.
Sense of Place 