A critical tree species found in some of America’s most revered national parks is in decline, leading researchers to embark on a race to prevent more from dying off. Whitebark pine, or Pinus albicaulis, is a keystone tree species found in the greater Yellowstone area, play a critical role in the ecosystem in the greater Yellowstone area, Laura Jones, branch chief of vegetation ecology at Grand Teton National Park, said. But the already few whitebark pine trees that exist on the rooftops of the Teton mountain range are dwindling quickly, and the impacts — while still unknown — could be a major disruption to the ecosystem, experts said. …One of the key steps to conserving the species is identifying the trees that are resistant to the pine rust and promoting those trees on the landscape, Jones said.