Denali National Park has closed to visitors due to the rapidly spreading Riley Fire near its entrance, prompting evacuations and a significant firefighting response.

Small spiny growths on a rosebush resemble spiny galls created by cynipid wasps.

There are over one hundred and forty landslides along the Denali Park road, the 92 mile road through Denali National Park and Preserve. None are more threatening than the Pretty Rocks Landslide at Polychrome Pass.

Kettle ponds in Denali National Park contain less water this spring than in previous years, due to low snowfall and permafrost thaw. Shrubs are replacing grasses as the lakes dry.

Beetles that killed millions of acres of trees in the 1990s were a first sign of climate change. In a new flare-up, they continue marching north as Alaska warms.

Of the 140 unstable slopes along the 92-mile park road, Pretty Rocks has the most potential to disrupt traffic.

John Craighead "Craig" George was swept under a logjam last Wednesday on the Chulitna River near Cantwell, Alaska State Troopers said. The dive team responded to the area Friday morning but found that the water was too high to deploy.The rafting party was decending when they encountered an unusual amount of logjams.

The aggressive infestation that took hold in the Matanuska-Susitna Borough north of Anchorage in 2016 has now spread north, covering hillsides in the communities outside the park with rustred dead trees and reaching into park boundaries.