Seeing and Observing Part 1: A Tale of Two Trails

PEEC Amateur Naturalist
Column by Robert Dryja

Sherlock Holmes has a lesson for us. It is taken from the story “A Scandal in Bohemia”: “When I hear you give your reasons,” I remarked, “the thing always appears to me to be so ridiculously simple that I could easily do it myself, though at each successive instance of your reasoning, I am baffled until you explain your process. And yet I believe that my eyes are as good as yours.”

“Quite so,” Holmes answered, throwing himself down into an armchair. “You see, but you do not observe. The distinction is clear. For example, you have frequently seen the steps, which lead up from the hall to this room.”


“How often?”

“Well, some hundreds of times.”

“Then how many are there?”

“How many? I don’t know.”

Like Dr. Watson in the story, how many times do we see the natural world around us, but do not observe it?

Let us take a hike on two trails that are similar in their physical geology. Deer Trap Mesa with its trail is easily accessed from Barranca Mesa in Los Alamos.

However the second trail in which we are interested involves a drive on N.M. 4 into the Jemez Mountains.

There is a parking area shortly before the turnoff to the St. Peters Dome Road (FR 289.) The trail head is across the street from the parking lot.

This trail is identified only as a Cross Country Ski Trail on some maps. Both trails are on flat mesa tops and both are easy to hike. An eagle will fly about nine miles in a straight line between the two mesas.

Both mesas face toward the east. The views from the ends of the trails at the mesa tips are panoramic.

Two major differences are easy to see. The Cross-Country Ski Trail is on a mesa that has had two major forest fires pass through it in the past 12 years.

The Deer Trap Mesa Trail, in contrast, shows no sign of fire. The mature ponderosa trees at the base of this mesa may be 100 or more years old.

This suggests that there has been no forest fire here for perhaps centuries. This is what we see, but what can we observe?

The views from the Cross-Country Ski Trail and Deer Trap Mesa Trail. Photo by Robert Dryja/

Observation shows that actually many areas of the Cross-Country Ski Trail have not been burnt in spite of the two recent fires.

Indeed there is only one area along the trail that appears to have been burnt twice. Other areas appear to have been burnt one time only or not all.

The fire from twelve years ago, the Cerro Grande, burnt large pine trees. Today their charred trunks have finally fallen to the ground.

The slow growth of mushrooms over the years on these fallen trunks also indicates that these trees were in the older fire. A mystery can be observed.

The fire went into the ground for some of these trees, burning tunnels where the roots had been. A distinctive set of holes has been created and the remains of the broken base of the trunk can be seen.

However, the rest of the burnt trunk is not to be seen. No sign of a burnt trunk can be seen on the ground around the hole.

How did the fire cause this? We now have an observation without an immediate answer.

Mushrooms on a charred trunk and a fire hole where roots had grown. Photo by Robert Dryja/

Other areas show the return of plant life one year after the more recent fire, the Las Conchas Fire. A forest of young aspen trees has grown two to three feet high.

Observation shows a pattern to this growth. The trees grow in clusters about four feet apart and in curving lines. What is going on?

The young trees are growing up from the roots of an original tree. Perhaps some of the roots of the original tree spread in lines rather than spreading randomly.

These roots are protected by the soil above them from any fire. New aspen trees therefore can begin to grow immediately after a fire.

A final surprise is waiting at the tip of the mesas. All you need to do is observe what is growing at your feet at the edge of the cliff.

Cacti are growing in groups in what is a forest of trees. What are desert plants doing here? These cacti have been here a long time judging from their size and how slowly they grow.

Did some bird bring seeds back from Deer Trap Mesa? Can the same species of cacti be found at Deer Trap Mesa?

Observe the top of the cactus in the photograph and be prepared to look for something similar in my next column.

New aspen tree growth. Some of the new trees grow in a line, perhaps following the path of a straight root of a prior aspen tree. Photo by Robert Dryja/

Cacti grow at the tip of the mesa of the Cross Country Ski Trail. Photo by Robert Dryja/

Want to Learn More? If you are interested in hiking these two mesas, send an e-mail to


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