13 May 2008

Tree Management To Improve Woodlands of Central Niobrara Valley

Planning is underway for tree management to improve woodland resources on the Niobrara National Scenic River east of Valentine.

The project - one of the first on state managed property in the area - will occur at the leased Krzyzanowski Tract with the renowned Smith Falls along a spring-branch creek, to the south across the river from the state park.

"With the fuels treatment effort, we are getting back to general forest management and providing avenues to increase forest health through proper stocking densities," said Jessica Yahnke, a forest fuels management specialist with the Nebraska Forest Service.

"Increased forest health means a healthier ecosystem," Yahnke said, and will enhance "wildlife habitat for deer, elk, turkeys and other animals. Snags will be left at a minimum of 2-5 per acre, to provide bird habitat."

The clearing will reduce the extent of "ladder" fuels and improve the vitality of the remaining trees.

"The Niobrara woodlands are growing 10-20 times the number of trees per acre than were present historically," Yahnke said. "If there is no fuel treatment by thinning or controlled burns, then there will eventually be a catastrophic wildfire, which could destroy whole woodland stands or large areas and thus, remove habitat for birds adapted and dependent on the horizontal and vertical edge that forests provide along the Niobrara River valley.

"The upper slopes that consist of ponderosa pine and eastern redcedar understory, will have both of these species mechanically removed. On the lowlands, most of the invasive redcedar trees will be removed from among the hardwood tree growth. Some hand thinning will occur on the midslope areas.

"Most of the understory trees consist of eastern red cedar, but also include ponderosa pine and hardwoods. Of these understory trees, most are considered 'ladder' fuels, which means they provide a means for a surface fire to gain easy access to tree crowns and a higher potential for fire spread. These ladder fuels combined with flashy fine fuels - such as grasses and yucca - in mountainous type terrain creates a volatile situation and thus, proposes a high risk threat for stand replacing wildfires."

The Big Rock Fire in mid-July 2006 on the north side of Valentine, is an example of this type of destructive fire which burns the trees and destroys the woodlands.

"A thinning project may cause the numbers of some bird species to decline to historic levels of occurrence in localized areas, as birds - American robins, for example - that utilize the cedar berries are displaced," Yahnke said, "but other redcedar trees are located both up and down river from the project area. Isolated patches of redcedar may still also remain where ladder fuel characteristics are not a concern and a break in fuel continuity can be accomplished to reduce the threat of unmanageable wildfire."

An evaluation visit with potential contractors will occur in mid-summer, Yahnke said.

Eradication of invasive Redcedar trees has been carried out elsewhere in the area along the Niobrara National Scenic River, especially by controlled burns and/or mechanical removal at the Niobrara Valley Preserve, owned by The Nature Conservancy, and to a lesser extent by private landowners.

Burning is also used as a grassland management tool at the Fort Niobrara National Wildlife Refuge, just east of Valentine.

No comments:

Post a Comment