A walk along the mile-long trail of the Lava Cast Forest gives you a glimpse of how recent volcanic activity has affected the local environment. The trail is located several miles directly west of Sunriver, Oregon in part of the Newberry National Volcanic Monument .
The Newberry National Volcanic Monument was established in 1990 and it preserves some unique features created in the recent geological past. Newberry volcano erupted 7,000 years ago and smooth textured pahoehoe lava flowed through a series of fissures along its northwest flank. This is known as the Northwest Rift Zone. The lava enveloped the forest creating lava trees and tree molds that are still visible today.
The most recent activity related to the Newberry volcano occurred 1,300 years ago. You can see the results of that activity by visiting the Big Obsidian Flow nearby.
The area is slowly recovering from the past volcanic activity and healthy plant communities can be seen along the trail. Ponderosa pine, lodgepole pine, white fir, and a variety of shrubs, grasses, and wildflowers are present. At certain times of the year, flowers such as Indian paintbrush and purple penstemon display a marked contrast against the grayish-black volcanic rock. Many plants have established themselves in the wind-blown ash that settled on the soil.
You may also catch a glimpse of some of the wildlife living in the area. The small mammal called a pika prefers to live in rocky habitats and you may hear its whistling call. Red-breasted nuthatch birds can be seen working down the sides of trees and heard calling in short nasal tones. Golden-mantled ground squirrels and yellow-pine chipmunks may scurry across the trail in front of you. A red-tailed hawk may drift over you carried by the warm thermals.
Remnants of a lava lake can be seen along the trail. Pahoehoe lava poured through a series of vents and settled into a depression.
Tree molds can be seen in many places along the trail. As lava flowed through the forest, it piled up along the upstream side of the trees burning them out but leaving a “mold” of the tree’s form. Some of the trees snapped off and were carried away by the lava; others fell to the ground and were hollowed out by the flows.
At one point along the trail you can see an island of trees surrounded by a rocky landscape. This feature is called a “kipuka”. This particular spot consists of older cinder cones that were encircled by younger lava.
To learn more about this and other volcanic features in the area, be sure to visit the Lava Lands Visitor Center located south of Bend. See this link for hours of operation and additional information. Note that this center is only open from May 1 to mid-October. http://www.fs.usda.gov/recarea/deschutes/recreation/recarea/?recid=38394