By John Pint

“There are interesting rock formations in the Primavera Forest between Río Salado and Tala,” I was told recently by Mario Guerrero, who has been hiking and camping all over Mexico since he was a boy. I figured if he considered a rock interesting, it ought to be curious indeed, if not bizarre. And I was right.

Mario, his friend Arturo Tejeda and I, headed for the Salty River via the western entrance to the Primavera Forest off highway 70. Mario’s objective was “Cañada Incognita,” a pretty canyon he had begun to explore, which, he said, we could reach “in 20 minutes” by bicycle.

We walked our bikes across the warm, shallow Río Salado, which is what Río Caliente is known as after it cools down a bit. Then we passed the cycles through a hole in a barb-wire fence, right under a sign saying “Private Property.”

“Don’t worry,” commented Mario, “that just means cars aren’t allowed in here.” I could see this was going to be another typical Mexican Adventure.

I somehow assumed a “20-minute” ride means we’d be following a flat road. Well, the dirt road was wide and smooth, alright, but flat it was not and it took a full two hours to reach Mario’s Unknown Canyon. When I pointed out the time discrepancy, I was told, “Bueno, we would have made it in 20 minutes if you hadn’t stopped to take so many pictures.”

We hid our bikes off the side of the road and headed into an impenetrable wall of underbrush. “Miseria,” said Mario, “last time I came here there was no maleza at all; lucky I brought this machete.” Ah, yes, a true Mexican Adventure.

While Mario furiously hacked at the maleza, Arturo—who was wearing shorts—complained that mosquitoes were eating him alive. “I can’t stand it! I’m cycling back home,” he announced and left. His home, by the way is in Tesistán, 22 kilometers away as the crow (but not the bicycle) flies. I did not get a single mosquito bite, which I attribute to the vitamin B Complex I take every day, which I highly recommend, because the dengue-carrying Aedes Aegypti is all over Guadalajara and was recently found at the outskirts of the Primavera Forest.

Dripping with sweat after advancing only two meters, Mario gave up his chopping and we backtracked to the site of the mysterious rock formations. These I have seen before in the Tala area where we named them “Fairy Footstools” (See Reporter, July 18, 2008). They look like tree stumps, about one foot wide and up to two feet high, but are composed of volcanic rock (rhyolite, apparently). What I found special about Mario’s find was that, because of road construction and subsequent erosion, the subsurface part of one “footstool” has been exposed, showing it to be a vertically oriented column of rock with a consistent diameter. While in the Ahualulco area, we have Piedras Bola (Great Balls of Rock), in certain areas around Tala there are mini-forests of these “Rock Footstools, sometimes numbering in the hundreds.

So how were these curious columns formed? Local geologist Chris Lloyd suggests they are “Bubble Trails” marking the places where gas bubbles rose through a cooling pyroclastic flow (an incandescent cloud shot out of a volcano at high speed), provoking crystallization. Eventually the degassing pipe gets completely full of particles which may later solidify and end up being much harder than the surrounding material, eventually standing out as pinnacles, columns or even lowly footstools. After sending pictures of these formations to other geologists, I learned that they are often called “fossil fumarole pipes” and examples can be found in Alaska, Oregon, Australia and elsewhere.


Instead of traveling to Alaska, however, you can see a lot of these Rock Pipes simply by taking a 4.5 kilometer walk (or bike ride) south of the Rio Salado.

We also found a very interesting trail only 3.7 kilometers from the river. This is a true hiker/biker’s delight, shady and narrow, which parallels a small river past all kinds of bizarrely shaped rocks, including some of those curious Fossil Fumaroles. We followed the trail for 450 meters till time constraints forced us to turn back, but we definitely plan to return and see where it goes.

By the way, we saw no cars, ATVs or human beings during our odyssey in “Transaladania,” my new name for the area south of the Río Salado.
  

How to get there

Take Highway 15 (Nogales) 25 kilometers west of the Periférico to Highway 70 (Ameca). Don’t get on the toll road by mistake! Go southwest on 70 toward Ameca for about 3.5 kilometers at which point you are about to cross over or detour around a bridge under reconstruction. Immediately after crossing over or under the bridge, turn left onto an unmarked dirt road heading southeast. Follow the main drag until you come to a fork with a big sign advertising a balneario. Along the way, you may be hit for a small “car fee.” Don’t go to the balneario, but bear left and you’ll soon come to some lavish buildings (private property) where you’ll now have to pay a ten-pesos-per-person fee. About 280 meters southeast of this point you’ll pass a fenced-in pool full of big fish and you’ll see the Río Salado dead ahead. Park next to the pool, cross the river, step through the convenient rectangular hole in the barb-wire fence and head southwest on a dirt road. After 1.9 kilometers, you’ll see a side road. Keep going straight. Next you’ll come to a big green, locked, iron gate with a convenient bypass for hiker-bikers. At 2.9 kilometers from the river you’ll see a road heading left, but you continue going straight. At 4.5 kilometers you’ll at last come to the exposed Fossil Fumarole Pipes (GPS N20 39.587 W103 37.145 datum WGS84). Walk due north from here to see a lot more of them.

Driving time from Guadalajara to the river crossing is less than one hour. This is also reachable from the Lake via Jocotepec, Santa Cruz and Tala. The turnoff to the Primavera Forest entrance road (dirt) is about 11 kilometers northeast of Tala. If you have a GPS, you’ll find this turn at N20 43.580 W103 37.159.