There are 14 numbered posts on Black Canyon’s Warner Point Nature Trail. They are keyed to pages in a booklet that visitors pick up at the trailhead which describes the trees of the woodland along the trail. Rotted with age, we gradually replaced them this fall with new ones; anchoring them in the rocky, shallow soil.
The work takes time, except for post number 13 at one of the aged pinyon pines near the end of the trail. The marker was fairly worn, but we pulled it out with little trouble. It was the last one for that day, so we could sit under the shade of the tree’s spreading branches for a short break.
We don’t exactly know the age of this tree, but studies in the 1940s and 1950s of tree rings from some nearby specimens, revealed ages that today approach 900 years. It started me to wonder about longevity in pinyon pines compared to that of people.
Modern medicine, in the human world, suggests that longevity might be realized by genetics, as DNA is gathered to study age-related diseases. Research related to the sequence of genes in the DNA could unlock the secrets of Illnesses like Alzheimer’s or Lou Gehrig’s Disease (ALS).
Species, perhaps all species, have DNA (a sequence of traits) that could mean healthier or less healthy individuals. In the drought of 2002 – 2004, large stands of pinyon pines in New Mexico and Arizona succumbed to lack of moisture. Their weakened condition opened the door to ips beetle attack. Beetles took advantage of weakened trees, and large quantities of the trees kicked the bucket.
Back in the shade of our old pinyon, I wonder if there are traits in pinyon trees that better equip them to tolerate temperatures as they warm and conditions as they dry out. Might the gene make-up of some individual trees help them to fend off a beetle attack? It’s a grand specimen; sometimes called by colleagues as the grandparent tree or the grand-pinyon tree. Over the years we have bonded with this denizen of time.
Studies have uncovered various conditions which can affect an individual pinyon’s chances when conditions go downhill. Soil, nutrients, rain and snow, competition from other trees, and temperature all play a part in survival success. Location is also critical. Pinyons on south facing slopes, like many on this ridge, face greater challenges than on north facing sides of hills and canyons.
A recent study of tree rings on pinyons showed that trees which have lived through wetter and drier periods, meaning they have abided through good and bad years, are more successful in getting through a warming period. On top of that, those which have survived to age 70 are more likely to live to a ripe old age than others.
An increase in heat has set the stage to a great deal of beetle kill for Douglas fir and mortality among aspen groves on the south side of Black Canyon. Overlooks and trails expose the die-off that has come about in only the past few years. Yet, after 26 years of hiking the Warner Trail, it’s hard not to have a concern for this grandparent pinyon that I have come to know.
I have sat with the tree as it helped me with the loss of my dad in 2006. It’s fun greeting the tree at the end of an arduous hike back from Warner Point to the river. Touching its bark, smelling the “piney” aroma on a hot summer day, knowing that the tree is part of a community of living things similar to our own human community, and sharing the glory of old age with visitors have all been part of my relationship.
The tree sits on the north facing slope of the canyon. It appears to have the usual advantages to survive. It’s hard not knowing if it might have a genetic advantage to live through increasing heat and lower moisture in the years ahead.
People who look to the future with promise often find additional years added to their life, whether it’s in their genes or not. It seems that other factors can contribute to longevity in both humans and plants.
Still, pinyon trees, like the grand pinyon inspire hope. Not an uninformed, ingenuous hope. This is a hope that gives flight to love of trees and woodlands. And in that regard the longevity question is less important than the pull given by that great old tree to have a heart open to the land.
Paul Zaenger has been a supervisory park ranger at Black Canyon of the Gunnison National Park since 1993. Other park assignments include Mount Rushmore National Memorial and Glen Canyon National Recreation Area.