LARAMIE – A new University of Wyoming bulletin contributes to the building knowledge base of post-fire ponderosa pine restoration across Wyoming and the West.

UW faculty members, students and others are exploring best management practices for restoring a ponderosa pine forest following the 2012 Arapaho Fire, which burned approximately 98,000 acres in the north Laramie Mountains of southeast Wyoming.

They are conducting the ongoing study at the 320-acre Rogers Research Site (RRS) in extreme northeast Albany County. The fire killed the majority of ponderosa at the site, which is owned by UW and managed by the Wyoming Agricultural Experiment Station (WAES) within the College of Agriculture and Natural Resources.

In 2015, a UW faculty-student team launched the long-term project at RRS to investigate the impacts of different restoration treatments applied to the post-fire landscape. Early findings are detailed in RRS Bulletin 5, Restoration of Ponderosa Pine Following High-Intensity Fire, Rogers Research Site, North Laramie Mountains, Wyoming. B-1298.5.

Ponderosa pine (Pinus ponderosa) has evolved to survive frequent, low-intensity fires, which clear out the understory. But high-severity fires like the Arapaho, which occurred during a severe drought, are killing the thick-barked trees, and research is still evolving to determine best management practices for restoring P. ponderosa forests following such fires.

“Extreme wildfire seasons are occurring concurrently with drought, and our research is trying to determine if utilizing management practices like broadcast-seeding ponderosa pine seed or hand-planting seedlings are viable options for reforestation,” said co-author Stephanie Winters, a graduate student in the UW Department of Ecosystem Science and Management.

“We are also trying to determine how soil microbiology and biogeochemistry change following a high-severity fire in a ponderosa pine ecosystem and how soil ecology is linked to seedling regeneration,” she said.

Winters’ faculty adviser and bulletin co-author, Linda van Diepen, an assistant professor in the Department of Ecosystem Science and Management, stated preliminary results emphasize the difficulty of ponderosa pine restoration in dry environments where climate change and forest management practices, including long-term fire suppression, have resulted in more frequent high-severity fires.

“Ponderosa pine regeneration following high-intensity wildfire is limited in mid-elevation, lower montane, dry forests in the Rocky Mountain region, including areas like the Laramie Mountains and RRS,” van Diepen said. “This is due to a reduction of seed supplies from living trees, warming temperatures and limited precipitation.”

The study at RRS was initiated by co-authors Mollie Herget, while a graduate student at UW, along with her faculty adviser, UW Professor Steve Williams, who has since retired. Among their goals were to determine which method of introducing ponderosa to the burned site is most effective for forest regeneration: natural regeneration, planting seedlings or planting ponderosa seed.

Of the original 2,400 seedlings that were planted in 2015, only 146 were still alive last year, a survival rate of 6.1 percent. At the same time, however, little natural regeneration has been observed.

The study is also examining whether various timber cutting treatments and the planting of native grass seed help reestablish ponderosa pine. Winters and van Diepen, with the help of others, will conduct additional surveys at RRS this year. They will also examine whether the various treatments affect soil biogeochemistry and the microbial community, and whether there is a correlation with forest restoration success.

WAES editor and co-author Robert Waggener said ongoing research at RRS is following the wishes of Col. William C. Rogers, who bequeathed his land in the north Laramie Mountains to UW in 2002, stipulating the property be used to conduct research relating to the improvement of forestry and wildlife resources in the area.

“Colonel Rogers, who believed in the education of young people, would be very pleased knowing that UW graduate and undergraduate students are carrying out studies in collaboration with their faculty mentors and others,” Waggener said.

The bulletin is available by going to uwyo.edu/uwe and selecting the Find A Publication link. Type the title of the bulletin or the bulletin number into the search field. RRS Bulletin 5 and other publications in the series are posted on the James C. Hageman Sustainable Agriculture Research and Extension Center website at bit.ly/RogersResearchSite.