In any case, a recent speaker, Nick Melcher of the USGS, whose talk I attended on this very topic had one suggestion (among many good ones) that I’ll bring up here.  In giving a formal talk to non-scientists start with the punchline.  Give the conclusions first and work your way back to how you came to these conclusions.   This sounds simple enough, but in our training in college and graduate school it is drilled into us to process from statement of the problem to hypothesis, to methodology, results, discussion and conclusions.  Suspense is sustained in the withholding of conclusions to the end, not in how we arrived there.  However, with a non-scientist audience starting with the fireworks could capture attention and even debate. The challenge is then to show the audience how you came to that conclusion.

I will try this sometime.   When I have some results, that is where I will begin.

My own research focuses on past climate changes and their impact on pinyon/juniper woodlands and the  people who relied on their resources on the Colorado Plateau.  For those who are not familiar with these woodlands, they cover a vast area of the Southwest at elevations between the lowland deserts and highland forests.  They are distinct in that the trees are short in stature with spreading crowns.  Along these lines they are sometimes referred to as pygmy woodlands.   Both pinyon and juniper (of which there are several species) are semi-arid adapted trees and have a marvelous ability to weather and survive changing environmental conditions, especially drought. That said, it is becoming more and more apparent that despite this survival ability, when conditions pass certain unfavorable thresholds mortality can ensue en masse. While trees can take decades to reestablish, mortality can occur quickly having an immediate impact on forest ecosystems. The recent pinyon die-off is a case in point. Growing in a semiarid environment pinyon is especially slow to reestablish and grow, thus the effects of the 2000s die-off will be seen on sowthwestern landscapes for decades to come.

Did warming temperatures play a role in the die-off?  Possibly.  Some scientists have suggested as much.   Warmer temperatures, through a variety of processes, can place trees under greater stress during drought conditions.  Experiments (not my own) are currently underway in the Biosphere 2 here in Tucson placing pinyon trees under simulated drought conditions at different temperatures to see how they react.  On the landscape, however we know that the 2000s die-off is not unique.  In the 1950s another period of extreme drought also led to a pinyon die-off across the southwest.   Questions abound. How was the 2000s drought different, was it warmer?  How different were the spatial patterns of mortality?  Which trees actually died in each drought – youngsters, mature trees, already decling trees?  And so on.

As I said in my last entry, my little drop in the bucket will be to add a longer term perspective to these questions.   We’ll see how it goes….

So, what do I do? Most broadly, I am interested in past environments, how they change, and how people have dealt with this change (and often actively partook in the change). I know this includes a lot of stuff – my interests are broad, so maybe I should focus on what I am doing for my dissertation.

I am looking at how climate shapes pinyon/juniper woodlands and how changes in the woodlands may have affected past peoples. Over the past few years (peaking in 2002-2003) millions of pinyon trees and a few junipers have succumbed to drought and pests on the Colorado Plateau. If you have driven around southeastern Colorado or northern New Mexico lately you may have noticed an awful lot of these dead trees along the road. Is this die-off a sign of our warming climate, where warmer droughts produce ideal conditions for weakened trees and heightened bark beetle reproduction? Or, are these woodlands prone to occasional die-offs which reset the ecological clock and open up niches for new young growth? Or, some combination of both? Finally, what are the implications for past peoples of the southwest who relied on the pinyon nut as a source of protein – ho might past die-offs change our view of the archaeological record? Using tree-rings I am attempting to provide a bit of perspective on the recent die-off by dating past mortality of pinyon. In a nutshell, I am picking-up old dead wood off the ground and dating when it died. With tree-rings from other species I am looking at past climate to see if there is a correlation between climate conditions and patterns of tree death. Simple enough in concept…

An all too common sight throughout the range of Colorado pinyon.

Over the next few months I’ll posting some of what I’ve done thus far and where I hope to be going. Up next though, is the first bi-weekly theme I have been assigned – climate change.

Soon again.