DESERT INSTITUTE
at Joshua Tree National Park
Spring Session
2016
74485 National Park Dr. Twentynine Palms, CA 92277
Phone: 760-367-5535; e-mail: desertinstitute@joshuatree.org
Summit Mary Peak
Information
Date/ Time:
Meet at:
Instructor:
Sunday, February 28, 8 am – late afternoon
Oasis Visitor Center (click on link for a map of the meeting site)
74485 National Park Drive, Twentynine Palms, CA
Mark Wheeler, Naturalist
Overview
Sitting right across the Pinto Basin from the imposing bulk of Pinto Mountain, Mary Peak is often
overlooked by hikers and passersby. It’s only 160 feet shorter than Pinto, but it tends to blend into the
Hexie Mountains skyline and escapes attention, that is, unless an observer is looking for geologic
irregularities. In that case, Mary’s vertical and broken north face catches the eye, suggesting that time
might have left more rocky exposures on the peak worth seeing. Indeed, the backside of Mary is riven
by a tight little drainage that has some of the showiest specimens of water polished rock in the park,
most of it a handsome rock called “gneiss.” There are other cliffs and rocky formations to see, but it’s
the gneiss that really steals the show. In addition, these gneisses contain the oldest rocks in the park,
dating to 1.8+ billion years. Some detail about this rock and the geologic history of the basin will be
shared during the hike.
Total round trip mileage is about eight miles in a loop, with an elevation gain of 2,000+ feet. There is
need for some rock scrambling in the backside drainage, but it is non-technical and limited. The entire
route is cross-country. If there are winter rains, wildflowers in this part of the basin should be peaking
right about now.
Itinerary
Sunday, February 28, 8 am – late afternoon
Oasis Visitor Center, Twentynine Palms
 Introduction
 Field class
 Lunch/snack break, bring your own food
 Field class
What to Bring to the Course
Optional Class Materials
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7.5” USGS Queen Mountain quad??
Compass
Camera
Binoculars
Field guides
Suggested Reading:
 John Sowell, Desert Ecology, University of Utah Press, 2001

Bruce Pavlik, The California Deserts, University of California Press, 2008
The 10 Essentials: Every day in the Desert
 Day pack
 4 quarts of water
 Closed toe hiking shoes
 Lunch and snacks
 Clothing layers
 Hat
 Sun glasses
 Sunscreen
 Notebook and pencil/pen
 Whistle
Fitness Requirements
Participants must be in good physical condition for courses/activities in a desert that may be hot, dry,
windy, and sometimes surprisingly cold.
Hike Level
Strenuous – 8 miles round trip
*People attending this hike must be in good physical condition and comfortable spending the day rock
scrambling as well as covering up to eight miles up and down the peak. Please call if you have
questions concerning your rock scrambling/hiking abilities.
Guidelines
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You are responsible for your safety.
Park your car in designated areas only. Parking along the side of the road is dangerous to
you and the environment.
Rattlesnakes are present in the desert. Avoid contact with wildlife. Put your hands and feet
only where you can see them.
Stay with the group. If you get lost, stay put.
Before leaving the class, check out with the Desert Institute Representative.
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Drink plenty of water. If you run out, notify the instructor or the Desert Institute
Representative.
Instructor Biography
Mark Wheeler has a M.S. in Education and a journeyman's degree in natural history, having spent
most of thirty years hiking and studying the mountain and desert landscapes of the west coast. Mr.
Wheeler has worked extensively with wilderness-adventure programming groups such as Outward
Bound, training both students and instructors in wilderness travel skills and group dynamics. A working
writer, he has focused on subjects about the natural world.
* The Desert Institute staff/instructors will attempt to accommodate participants needs, however we
reserve the right to deny a student participation in the course due to concerns regarding health and
safety issues.