Saving Whitebark Pine: Infrastructure Funds Back Recovery in 10 National Parks

A mature whitebark pine at Crater Lake National Park. NPS / Jen Hooke.

Whitebark pine is a keystone species of the mountains of the western United States and Canada. It grows slowly in near-constant wind and bitter cold, as high as 12,000 feet, and its old trees are gnarled and twisted, with silvery trunks and needles like a bad case of bed head.

A tree in trouble

Scientists estimate more than half of standing whitebark pines are dead, from mountain pine beetle outbreaks, fire and the non-native white pine blister rust. Climate change — warmer conditions and shifting precipitation — may add to the damage. Together these led the U.S. Fish and Wildlife Service to list the species as threatened under the Endangered Species Act.

The die-off has crept across the mountains in waves since the early twentieth century. The loss would reach far beyond the scenery:

• Food: its seeds are high-energy food for Clark's nutcrackers and grizzly bears.
• Water: healthy stands slow snowmelt runoff, reducing erosion and protecting water quality and supply.
• Ecosystem: it shapes the lives of many other native plants and animals.

Blister rust on a whitebark pine. NPS photo.

About blister rust

White pine blister rust is a lethal fungus of five-needle ("white") pines, probably from Asia, that reached the U.S. from Europe early in the 20th century. Five U.S. five-needle pines are susceptible, including whitebark.

Its life cycle needs an alternate host — currants, gooseberries or paintbrush. Spores from those plants blow onto pines and can kill whitebark from sapling to mature tree.

A failed fix: when the disease appeared in the 1930s, several western parks tried to stop it by destroying the alternate hosts. For four decades, big crews tore out countless native plants and sprayed more than half a million gallons of the herbicide 2-4-5T in national parks. In 1971 the effort was judged ineffective and stopped.

The strategy now: resistant trees

1. Find "plus trees" that show no rust.
2. Collect their seed and test seedlings in nurseries by exposing them to rust spores; proven ones are "elite trees."
3. Plant resistant seedlings back out.

It is slow and costly. Some parks are testing direct seeding — planting seed straight into the ground instead of spending 2–3 years raising seedlings — and genetic research may speed up spotting resistant trees, for example from needle samples. Over the past 15 years, ecologists at several parks have found trees that seem resistant; in some areas more than 60 percent of their seedlings have survived rust exposure.

What the new funding does

Money from the Bipartisan Infrastructure Law and the Inflation Reduction Act supports recovery at 10 parks: Crater Lake, Sequoia and Kings Canyon, Lassen Volcanic, North Cascades, Grand Teton, Olympic, Mount Rainier, Yellowstone, Glacier and Yosemite. Beyond finding resistant trees and growing seedlings, more staff and partners will let parks collect and store seed in "mast" years, when the pines make huge seed crops every three to five years.

"The infrastructure law funding is a once-in-a-career, long-term opportunity to push back against the die off of white pines," said Dr. Steve Buckley, an NPS ecologist. "The overarching goal is to save the biodiversity of these forests."

Climate's part

A warming climate helps the beetles: winters are no longer cold or long enough to control them. For blister rust the picture is less clear. Its spores ride cool, moist summer air, and how climate change alters that will vary across the range. Research is under way on the tree's vulnerability to future climates.

Reaching the trees often means long hikes over hard ground. NPS photo.

The hard work of collecting

• Remote: the trees grow high in rugged mountains, mostly in designated or proposed Wilderness, where motorized equipment is restricted.
• Twice over: a technician climbs each tree to cage the developing cones against birds and animals, then returns to harvest them. "And we do it twice," said ecologist Beth Fallon of Mount Rainier, describing hikes of several miles through thick vegetation with no roads or trails.
• Irregular crops: mast years come every three to five years. North Cascades' last was in 2021; the next was expected in 2025.

Clark's nutcracker, the pine's partner. NPS / Jim Peaco.

Seeds that need help: whitebark seeds are too heavy for the wind. Clark's nutcrackers, which evolved with the pine, cache seeds sometimes more than 11 miles from where they found them; squirrels store cones in middens; grizzly bears raid the middens or climb for cones to fatten before hibernation. Steady federal funding will let restoration crews keep collecting seed, growing seedlings and planting them out for years to come.

Sources

Based on "Bipartisan Infrastructure Law and Inflation Reduction Act support range-wide efforts to rescue disease-addled whitebark pine," National Park Service; a work of the United States government in the public domain.