Bipartisan Infrastructure Law and Inflation Reduction Act support range-wide efforts to rescue disease-addled whitebark pine forests

A keystone species of the western United States and Canada, whitebark pine live in near-constant wind and bitter cold high in the mountains. They grow slowly at elevations up to 12,000 feet. The oldest and even the not-so-oldest are gnarled and twisted with silvery trunks and needles often grouped like a serious case of bed head.

Mature but scraggly whitebark pine tree in Crater Lake National Park.

NPS / Jen Hooke

It’s an edgy existence and scientists estimate more than half of standing whitebark pines are dead from the combined effects of mountain pine beetle outbreaks, fire and the spread of the non-native white pine blister rust. A changing climate, with warming conditions and shifts in precipitation, also may negatively affect stands of whitebark pine. Taken together, these challenges contributed to the U.S. Fish and Wildlife Service decision to list the species as “threatened” under the Endangered Species Act.

The die-offs didn’t happen quickly. Scientists and land managers have seen the damage creep across the mountains since the early Twentieth Century. The destruction comes in different waves of blister rust and pine beetle outbreaks.

There is much to lose beyond the stunning visual impact of whitebark pines. This species influences the health and life cycles of other native plants and animals. It provides a high-energy food source for animals like the Clark’s nutcracker and the grizzly bear. Healthy whitebark pine stands play an essential role in slowing runoff from snowmelt which reduces soil erosion and protects water quality and supply.

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Blister rust on a whitebark pine.

NPS Photo

About blister rust

White pine blister rust is a lethal stem rust fungus of five-needled or " white" pines. It is a non-native disease that is thought to have originated in Asia and come to the U.S. from Europe early in the 20th century. There are five susceptible species of five-needle pines in the US, including whitebark pine. 

Blister rust has a complex life history involving an alternate host from plants such as currants, gooseberries and paintbrush which are key components of the infection transmission to five-needle pine trees. Spores from fungus grow on alternative plants and then release into the air and attached on pine trees, which infects and can kill whitebark pine from sapling to mature tree. 

When the disease was detected during the 1930s, several western national parks tried to control the disease by removing the alternative host plants. This campaign was intended to save the pines at the expense of other native species and resulted in the destruction of uncounted numbers of native plants, the spraying of over half a million gallons of the herbicide 2-4-5T in national parks, and a huge effort by large crews of workers for four decades. In 1971 the effort was deemed to be ineffective and discontinued. 

Current research is focused on identification of rust resistant trees for seed harvesting and replanting to grow stands which carry natural immunity, or reduced susceptibility, to blister rust infection.  Seed collection of “plus trees” - trees that don’t appear to carry any rust infection, and further nursery testing to identify “elite trees” - trees that are proven to have rust resistance, is a long and expensive process. To help streamline the process, some parks are studying how effective direct seeding is – putting seeds directly in the ground versus taking 2-3 years to grow them as seedlings.  Additional research on the genetic makeup of elite trees is underway that may shorten the process of identifying rust resistant trees via faster methods such as needle sample testing.  

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The funds this year enabled whitebark pine recovery work at these national parks: Crater Lake, Sequoia and Kings Canyon, Lassen Volcanic, North Cascades, Grand Teton, Olympic, Mount Rainier, Yellowstone, Glacier, and Yosemite. In addition to identifying disease resistant trees and cultivating rust-resistant seedlings, increased staffing and expanded partnerships will also allow parks to collect and store seed during years when the pines produce massive amounts of seed during “mast events” that come along every three to five years.

These new funding opportunities come at a critical time for whitebark conservation. The influx of project support has energized the whitebark pine conservation community whose members have been working on restoration for decades.

“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, a National Park Service ecologist. “The overarching goal is to save the biodiversity of these forests.”

Our warming climate favors the beetles because winters aren’t cold enough or long enough to control the insect. The effects of climate change on the pines from blister rust is not as clear. Blister rust spreads through spores that are carried on summer’s cool, moist air currents. How climate change affects these moisture conditions will vary across the range of whitebark pine. Recognizing the importance of understanding climate change impacts to conservation of whitebark pine, there is research underway on the vulnerability of whitebark pine to future climates and its stressors.

Climate connections aside, scientists have discovered and are further refining a strategy to combat the decline of whitebark pine forests. In the past 15 years, ecologists at several parks have identified trees that appear resistant to rust infection. They have collected seeds, started seedlings and exposed them to the blister rust spores in nursery settings. The survival rate has exceeded 60 percent for those seedlings in some areas. With expanded funding from the Bipartisan Infrastructure Law and the Inflation Reduction Act, parks will train more staff and form partnerships to provide additional people to collect and test more seed and seedlings and plant out seedlings in more areas across the whitebark pine range.

Getting to the trees often requires long hikes through difficult terrain.

NPS Photo

How this species saving strategy works

Identifying healthy trees in blister rust infected stands is relatively simple. Rust resistant trees don’t show signs of the disease that slowly kills the tree. The season to find whitebark pine that are resistant to the rust is short and getting to the trees often requires long hikes through difficult terrain. The trees are at high altitudes in rugged mountain environments. And they are mostly within designated or proposed Wilderness areas within national parks which poses additional administrative challenges – like a restriction on the use of motorized equipment for conservation actions. Once found, the seeds must be protected from birds and other wildlife until they are mature and can be harvested. The proven method is for a technician to climb the tree and place cages over the developing cones.

Ecologist Beth Fallon of Mount Rainier National Park said it can be a hike of several miles through thick vegetation – no roads or trails – to reach these target trees. “And we do it twice. Once when we put the baskets or cages over the cones we want to collect and again when it’s time to collect the mature cones. These operations span several days.”

Clark's nutcracker.

NPS / Jim Peaco

There are additional hurdles for the ecologists. Many species expand because their seeds can float on the wind to new growing areas. Not so with whitebark pine seeds. They are relatively heavy, too heavy to be scattered by the wind. They are tough seeds and disperse only with the help of wildlife or people. The Clark’s nutcracker has evolved with whitebark pine. These birds cache seeds for future consumption sometimes more than 11 miles away from where they are collected. Squirrels collect cones and store them in middens within whitebark pine stands. Grizzly bears devour the rich seeds, found in middens or by climbing the trees to reach cones, to put on fat before hibernation.

Whitebark pine seed production isn’t steady and that’s another limiting factor. They produce massive amounts of cones every three to five years. The last cone mast in North Cascades National Park, for example, was in 2021. The next is expected in 2025. The availability of federal funds over time will help restoration experts to continue to be able to collect seed, grow seedlings, and plant them out in forests well into the future.

About the Bipartisan Infrastructure Law

The Bipartisan Infrastructure Law makes critical investments in the resilience and restoration of America’s lands, skies, and waters, and enhances conservation and recreation opportunities. Visitors will see tangible results such as repaired and upgraded trails and campgrounds, removal of invasive species, as well as healthy wetlands, grasslands, and forests. 

Inflation Reduction Act

The Inflation Reduction Act provides the National Park Service with a historic opportunity to address critical ecosystem resilience, restoration, and environmental planning needs. Projects funded in national parks represent broad-scale and impactful resource investments across every corner of our nation—from Alaska to Florida to Maine.