By Mary Stuever

Approximately a hundred and fifty foresters and range managers met in Albuquerque in September 2006 to learn about Pinyon-Juniper woodlands. The conference was a joint meeting of the Society of American Foresters and the Society for Range Management. It wasn’t the first time a conference had been held to focus on the “short stature” trees. As one speaker pointed out, six previous workshops stemming from 1975 to 1997 had generated 272 articles on over 1600 pages of proceedings. Of course all this was before pinyon trees started dying by the millions.

Fifty-four million dead pinyons in New Mexico, one speaker suggested. That would be 100 million dead trees throughout the pinyon pine’s (multiple species) range in the United States, which takes in the bulk of New Mexico, Arizona, Colorado, Utah, and Nevada. That’s only about 15% of existing trees, another speaker optimistically offered. Tell that to someone in Santa Fe, Abiquiu, Prescott, or any other die-off “hotspot” where at least to the untrained eye, almost every pinyon seemed to have taken the hit. The tree counters have interesting data though. It seems that no size class has been immune. The deaths of small, little, medium, large, and granddaddy trees seems to follow classic “J” shaped curves indicating that all age classes are experiencing the same ratio of mortality.

Throughout the three-day conference both agreement and disagreement emerged among the presenters. Everyone seems to agree that many pinyon trees died during the 1950s’ drought, but whether this current die-off event is much larger was debated. Bark beetles are universally blamed as the primary causal agent of the tree deaths, however opinions varied on the drought conditions that weakened the trees and made them vulnerable to the beetle outbreaks. Some feel recent dry periods are part of normal weather fluctuations while others feel global warming is a key part of the equation.

Overall, there were few tears shed for the trees that had died. The general consensus is that, in the absence of regular fires burning across the landscape as in pre-settlement times, pinyon and juniper trees have been increasing in our woodlands and grasslands.  The trees intercept and transpire rainwater that would have otherwise entered into groundwater, streams, and springs. In addition, grasses and wildflowers are more likely to flourish where tree numbers have decreased. When these plants grow beneath trees, soils are less likely to erode. A study at Bandelier National Park illuminates this situation. On a 1/10 hectare plot in dense woodland, over 1,000 potsherds were found in soil that had eroded from just one storm event.

The final conference day focused on ways to thin woodlands and to utilize wood products. Pinyon and juniper firewood can be used for more than heating homes via the traditional wood stove. Power plants burning woody biomass produce far less pollution than coal burning plants. Not only is energy a marketable commodity, but energy credits gained by creating less pollution can be marketed to companies and countries in need of such credits to meet world-wide air quality guidelines. A businessman attending the conference also shared challenges of creating new products utilizing pinyon and juniper wood fibers.

Pinyon-juniper woodlands cover approximately one quarter of New Mexico and over one eighth of Arizona. These lands provide water, forage for livestock and wildlife, wood products, and recently a vast expansion of home sites. Foresters and range managers who attended the conference, and those who will read the resulting conference proceedings, are better prepared to make management decisions regarding this important and seemingly fragile ecosystem.