There is minimal foliage directly at the site, but please be respectful of the park, any nearby foliage and wildlife, and always do CITO. Be especially careful of deer if traveling at dusk.
FTF: tugies!
The summit of Mount Lemmon (In O'odham: Babad Doʼag) is 9,159 feet, and is the highest point in the Santa Catalina Mountains. Located in Coronado National Forest, it was named for botanist Sara Plummer Lemmon, who trekked to the top of the mountain with her husband and E. Stratton, a local rancher, by horse and foot in 1881.
Hoodoos
At first glance the hoodoos you see around you may seem similar to pinnacles, but actually they are quite different. Pinnacles in Mt. Lemmon are straight-sided, typically made of granite, and formed by water seeping into cracks and then freezing and melting. Hoodoos in this area are made of volcanic ash and other soft stone materials, topped with a harder material, and formed by weathering from rain. They have irregular edges and often have a totem pole shape and varied colors due to the varying erosion of softer materials, and wear a "hat" of less erosive material on top.
The name hoodoo came from early pioneers who, when they saw these rocks emerging from the mist, thought they looked like magical beings. The name refers to the use of energies in Hoo Doo, a form of pagan magic that came to prominence in the 1800s. The French call hoodoos demoiselles coiffées, which translates to “ladies with hairdos,” referring to the “hat” that hoodoos wear that their cousins pinnacles do not. While you travel around the park notice many of the hoodoos resemble people with hats, and seem to be speaking to one another in little rock communities.
A hoodoo, also called a tent rock, fairy chimney, or earth pyramid, is a tall, thin spire of rock that protrudes from the bottom of an arid drainage basin or badland. Hoodoos can be found on every continent, but nowhere else on earth are hoodoos more abundant than in Bryce Canyon National Park, in Utah.
Bryce Canyon hoodoos
Formation
Millions of years of erosion have placed hoodoos along the side of Mt. Lemmon. These stone were birthed by volcanic eruptions spanning 35 to 25 million years ago. They exist in high dry desert communities called “sky islands,” isolated forested mountains surrounded by radically different lowland environments. Geologists state these rocks are volcanic ash which fused into welded Rhyolite tuff (consolidated volcanic ash), with subsequent erosion creating the tall spires and columns. This is different from the Bryce Canyon hoodoos, which are limestone based and formed by frost wedging.
Hoodoos range in size from 15 feet tall to heights exceeding that of a 10-story building. Hoodoo shapes are affected by the erosion patterns of alternating hard and softer rock layers. Minerals deposited within different rock types cause hoodoos to have different colors throughout their height.
Hoodoos typically form in areas where a thick layer of a relatively soft rock, such as mud stone, poorly cemented sandstone or tuff is covered by a thin layer of hard rock, such as well-cemented sandstone, limestone or basalt. In glaciated mountainous valleys the soft eroded material may be glacial till with the protective capstones being large boulders. Over time, cracks in the resistant layer allow the much softer rock beneath to be eroded and washed away. Hoodoos form where a small cap of the resistant layer remains, and protects a cone of the underlying softer layer from erosion. Further erosion of the soft layer causes the cap to be undercut, eventually falling off, and the remaining cone is then quickly eroded.
Rain is the chief source of the erosion that sculpts hoodoos. The summer monsoon rainstorms travel through the region, bringing short duration but high intensity rain. Rainwater is slightly acidic, which lets the weak carbonic acid slowly dissolve limestone grain by grain. It is this process that rounds the edges of hoodoos and gives them their lumpy and bulging profiles. Where internal mudstone and siltstone layers interrupt the limestone, you can expect the rock to be more resistant to the chemical weathering because of the comparative lack of limestone. Many of the more durable hoodoos are capped with a special kind of magnesium-rich limestone called dolomite. Dolomite, being fortified by the mineral magnesium, dissolves at a much slower rate, and consequently protects the weaker limestone underneath it.
Thor’s Hammer hoodoo, Bryce Canyon, UT
Tea Tables
Tea tables are a variety of hoodoos. A tea table is a rock formation that is a remnant of newer strata that have eroded away. A tea table is a type of rock column comprising discrete layers, usually of sedimentary rock, with the top layers being wider than the base due to greater resistance to erosion and weathering. Sometimes these occur just beyond bluffs or cliffs at the end of a ridge; sometimes they are the only rock formation remnant on top of a ridge or even on fairly level ground.
Devil’s Tea Table, Athens County, Ohio
Logging Requirements
Please email answers to these questions through messaging or CO profile. Short answers are fine.
1. Look to the north of the Hoodoo Vista parking area. Notice the "stone man" sitting against the wall in his cloak with his hat on. Optional: Take your photo with him/this hoodoo behind you and post with your log. (To see an excellent photo of the formation I mean, see Copperwings' photo in his log of Oct. 18, 2016, or see his photo in the gallery.)
2. Are the hoodoos around you formed from frost wedging or erosion of tuff made from volcanic eruptions?
3. What are two differences between hoodoos and pinnacles?
4. Turn around and carefully cross the street to the listed waypoint, taking care with children and dogs, to touch the large wall of rock there. What is the texture of the granite in front of you? How does it compare to the apparent texture of the large stone perched on top of the granite? How does this relate to hoodoo formation?
References: https://en.wikipedia.org/wiki/Mount_Lemmon, http://www.crystal-life.com/blog/hoodoo-rocks-of-mt-lemmon/#sthash.EqK8QTic.dpuf, http://www.crystal-life.com/blog/hoodoo-rocks-of-mt-lemmon/, https://en.wikipedia.org/wiki/Hoodoo, https://en.wikipedia.org/wiki/Tea_table, https://en.wikipedia.org/wiki/Geology_of_the_Bryce_Canyon_area