The YETMAN Trail

What may be the first in-person gathering of Pima County Master Naturalists (PCMN) since we started Zooming our Board Meetings back in March of 2020 took place in the Tucson Mountains on Wednesday, June 16, 2021. Six MNs and a family member initiated the PCMN hiking Program with a four mile hike along a section of the Yetman Trail. Although it was already well into the 80’s at 0615 when we started, everyone was excited and prepared for the desert heat.

Photo: Avery Lane
Pictured here at the historic Bowen Stone House are (L-R) Josh Ruddick C1, Jessica Paul C4,
Jean Boris C2, Franklin Lane C1, Penny Marshal C2 and Melissa Mundt C5

This particular route was selected because it is a great ‘novice’ desert trail. One goal of the PCMN Advanced Training Committee is to encourage members to enhance their appreciation of the Sonoran Desert by offering an introductory level course on local hiking. While together, the group discussed an informal curriculum that could qualify for either Advanced Training (Skills) or minimally, Advanced Training (AT) credit. Hikes, especially more challenging ones, would also be offered simply for recreation and comradery. Something we can all certainly use! Our new C5 colleague, Melissa, also suggested a family and friends options that we will explore.

“We have Master Naturalists, including me, that relocated to the Sonoran Desert, as well as local folks who have not hiked much. The AT Committee would like to offer various levels of hiking classes so MNs can hike safely, and learn new trails. Hiking with other MNs also brings the added dimension of their knowledge in specific areas, so much shared knowledge occurred on this awesome first in-person class since Covid hit!” Penny Marshal, Chair PCMN Advanced Training Committee

While there are several accesses to the Yetman Trail, this inaugural hike left from the Camino de Oeste Trailhead near the west end of Speedway at Gates Pass Rd. The first half mile is through a nice steep canyon so was shaded a bit from the rising sun both in and out. The historic Bowen Stone House is at the 1.5 mile mark. A good turn-around point and Southern vista is at 2 miles.

Photo: Jean Boris
Hikers explore the Bowen Ranch House built in the early 1930’s by Sherry and Ruby Bowen.
At the time, Sherry was city editor of the Arizona Daily Star

At the turn-around point we could see the Clearwater Renewable Resource Facility. Jean Boris subsequently researched it and learned that this is where Central Arizona Project (CAP) water is stored after it is pumped up from the aquifer before delivery to our taps.

As mentioned, an added advantage to hiking with other Master Naturalists is the knowledge that can be shared. Josh Ruddick explained/showed how rock lichen reflects local air quality. An amusing memory aid was offered; “Alice algae took a lichen to Freddy fungus but we hear their relationship is on the rocks”

The group also observed and discussed the abundance of Saguaro blossoms this year. The theory being that it’s a species response to the challenging conditions of draught and excess heat. Everyone was also offered some of the ‘candy of the desert’.

Photo: Penny Marshal

We were able to develop a strong curriculum of ‘best practices’ for hiking in the desert which we’ll begin offering on future hikes. Topics range from trail safety and protocol to hydration and equipment. In the meantime you can contact the Advanced Training Committee with any specific questions. Our hiking sub-committee includes Paul Stillman C3, Deb Huie C1 and myself.

Franklin Lane

Palo Verde: The Sonoran Desert Tree of Life

Capstone Presentation created by Pima County Master Naturalist Intern Marcia Lambert from Cohort 5.

City nature Challenge 2021 Wrap-up

Round-tailed ground squirrel by southwestsemanticist on iNaturalist.

April 30 through May 3, 2021 the Arizona Master Naturalists participated in the City Nature Challenge where community members documented plant and animal species using the app iNaturalist. The City Nature Challenge is a global project and 1,270,767 observations were made this year. Over 45,300 species were identified and more than 2,100 rare, endangered, and threatened species were observed. Over 52,777 observers participated in the event while enjoying the outdoors as volunteer community scientists.

Here in Tucson about 200 people participated in the event! Over 2,500 observations were made and included over 640 species. Our most common observations included:

Prickly pears by restringham on iNaturalist
  • Saguaro, 35 observations
  • Fish hook barrel cactus, 28 observations
  • Creosote bush, 24 observations
  • Desert spiny lizard, 24 observations
  • Common slider, 23 observations

Our top Observers included usernames:

  • Direwolfplayz – 335 observations of 70 species
  • JMarvin – 164 observations of 126 species
  • Roomthily – 139 observations of 71 species

The locations in which observations were made could reflect where accessible natural spaces exist in our city. Tucson is located at the base of surrounding mountains and is famous for being surrounded by parks and trail systems. By looking at the City Nature Challenge’s interactive map we can see that participants were able to make observations both within our parks and our urban environment!

Check out what observations were made by visiting the Tucson City Nature Challenge Website.

Thank you to everyone who participated and enjoyed the outdoors while celebrating community science month, and special thanks to our community members that helped coordinate this event!

The Arizona Trail

My youngest daughter (Avery Lane) just completed the 800 mile Arizona Scenic Trail (AZT). I provided logistical support and accompanied her on a few of the segments. It took her (50) days to complete the (43) passages from the Mexican border, in the Huachuca Mountains, to the Utah border on the the Kaibab Plateau.

Start 3/25/2021
Finish 5/13/2021

The first couple of miles are a bit odd. You can park at Montezuma Pass in the Coronado National Monument but then must hike south for ~2 miles to the obelisk marker at the actual border. When Avery and I did this section, the trail to the border was still ‘technically’ closed due to border wall construction…..!

Coincidentally new wall construction ended exactly at the AZT Trailhead on 1/20/2021! To the left (east) is still the original wire fence.

As you turn back and head north you pass Coronado Peak. This is where Dale Shewalter, a Flagstaff public school teacher, envisioned the idea of linking trails on private and public land to span the entire State. The last passage of the AZT was completed in 2012. There is a Golden Spike on Passage 16 just north of the Gila river to commemorate this accomplishment.

The remainder of this post will attempt to show some of the amazing biogeography of our State. Hopefully it will encourage you to consider exploring some of the passages. Most people who enjoy the AZT are not ‘through-hikers’ but rather divide it up over time. Please feel free to contact me or Avery if you have any questions. Contact info below or through Pima County Chapter of the Arizona Master Naturalists.

Agave parryi var. huachucensis
Captured on a UofA Jaguar Monitoring Camera on Miller Peak

From mountain snow to desert heat.
Quemada Canyon near Colossal Cave, Vail Arizona
Water where you can get it in the desert. North of Oracle Az.
Gila River near Kearney
West of Superior Az.
Champion Juniper in Reavis Canyon
Mazatzal Peak in the Tonto National Forest just south
of Payson Az.
Snow again near Mormon Lake SE of Flagstaff. But coffee helps!
And just when you think you’re almost done; The Grand Canyon!

Franklin Lane

Volunteer Spotlight: Burrowing Owl Project

Pima County Master Naturalists Penny M and Joshua R recently volunteered with Wild At Heart’s Burrowing Owl Project. Wild At Heart (WAH) is a nonprofit conservation organization that rescues, rehabilitates, and releases birds of prey. Their Burrowing Owl Project creates artificial burrows for owls and relocates owls from upcoming development sites to safe spaces throughout the region.

Wild At Heart was created in 1993 and was the first program to create artificial underground owl burrows. Bob and his wife “Sam” Fox, founders of WAH, identified a need to build artificial owl burrows in Arizona and began this relocation program. In 2001, Greg Clark became Wild At Heart’s Burrowing Owl Habitat Coordinator who expanded Wild At Heart’s rescue and relocation procedures.

“We are currently in one of the high intake periods where owls are being trapped to remove them from new development areas at a rate of 400-500 per year,” shares Clark. “Last year I relocated 400 Burrowing Owls but we still have owls coming in and we are in a foot race to get more habitat installed so owls can be relocated as fast as possible.”

Volunteers are part of this solution! Wild At Heart burrowing owl events are open to the public. Thousands of volunteers have helped build over 6,000 artificial burrows — providing homes for 2,500+ owls.

Western burrowing owls (Athene cunicularia hypugaea) are charming little owls who get their name from nesting in underground burrows. They incubate and raise their chicks within burrows that they borrow from other species like prairie dogs and ground squirrels. Burrowing owls are vulnerable to predation from a variety of other wildlife and are especially vulnerable to construction and land development projects. The western burrowing owl is the only fossorial owl species in the Americas, and is endangered in Canada, threatened in Mexico, and a species of special concern in the United States.

“Land next to active irrigated farmland is preferred by the owls,” says Clark. “Marana is one of those areas. Most of the owls come from Maricopa and Pinal Counties. Specifically, Buckeye is in the bullseye right now. Perhaps your chapter can help us find more land for relocation.”

If you are interested in helping The Burrowing Owl Project or volunteering with Wild At Heart you can donate, head to their website, follow them on FaceBook, or contact them at

Burrowing owl eggs inside of an artificial burrow.

Create Habitat for Sonoran Desert Wildlife in Your Backyard

Capstone project created by PCMN Erin Posthumus.

Resources and Reading list:

Selecting native plants:
Top 10 plants for birds in Central Arizona:
Habitat for Lizards:
Plants for Pollinators:
Arizona Game and Fish: Reading list for Landscaping for Wildlife:

Arizona Game and Fish: The Wildlife Friendly Garden
The Arizona Native Plant Society: Native Gardening
Center for Biological Diversity
Desert Connections: A Partnership between Tucson Botanical Gardens and Pima County Public Library

A Rare Beauty, Crested Saguaro

A capstone Project Created by Don Featherstone

Cristate Saguaros, also known as fasciation, is a relatively rare condition in which the growing tip, or apical meristem, of a vascular plant exhibits abnormal growth. The apical meristem is normally concentrated around a single point which allows for approximately cylindrical growth. Instead, the tissue becomes elongated perpendicular to the intended direction of growth. This results in a flattened, ribbon like crest or elaborately contorted tissue.

Cristate are known to occur in over 100 species of plants including many cacti, aloe,acer, euphorbia, digitalis and even cannabis. It is not known what causes cristate but there are many hypotheses: A. genetic mutation B. micro-organisms C. hormonal activity D. damage due to freezing or lightning

A cristate saguaro will still produce viable flowers, fruit and possibly arms emanating from the crest. The incidence of this condition is uncertain but is believed to occur in 1:200,000 to 1:250,000.

In 2005, two members of the Tucson Cactus and Succulent Society (TCSS), Bob Cardell and Pat Hamness, created the Crested Saguaro Society ( whose mission is to find and document all crested saguaros in the Sonoran Desert. At its inception, there were believed to be approximately 200 crested saguaros in existence. To date they have documented over 2000.

Pima county 772 Pinal county 57 Maricopa county 405 Cochise county 158 Yavapai county 112 Graham county 49 La Paz county 10. Mohave county 7. Santa Cruz county 3. Yuma 2


Richard D Moore , Too Tough to Die

The Botanical Review, Fasciation, vol 14, no 6

SKY ISLANDS: A Recipe for Biodiversity

Capstone Project written by PCMN Carrie Barcom

I came across a brochure in the Sabino Canyon Gift shop titled, “Map of Sky Island Scenic Byway”. I know a lot has changed in the 16 years I’ve been away from Tucson, but when did we get Sky Islands? And more importantly, what are they?

Sky islands are a type of continental or inland terrain made up of a sequence of alternating valleys and mountain ranges. Isolated mountains are separated from one another by physical distance resulting in a mountain “island” surrounded by “oceans” of desert or grassland. The slopes and summit have a dramatically different ecosystem from the base and distinctly different biospheres occur all the way up the mountain with various types of life existing at each level. Sky islands have a stack of biotic communities that allow seasonal vertical migration between highland and lowland habitats but the valleys between them act as a barrier preventing species from crossing from one mountain range to another. There are about twenty groups of sky islands on the planet, all continents with the exception of Australia harbor sky island complexes.

One of the most renowned chains of sky islands can be found in an exspansive cluster in Arizona, New Mexico and northern Mexico, known collectively as the “Sky Islands”, “Madrean Sky Islands” or “Madrean Archipelago”. The descriptions of this area read like a giant cosmic recipe for biodiversity: Begin by connecting the massive continental back- bones of the Rocky Mountains with the Sierra Madre Occidental. Blend in temperate, sub-tropical, and tropical latitudes. Add a dash of elevation, sometimes up to a 6,000 ft. gradient from valley to mountain peak. Flank these peaks with the Chihuahuan and Sonoran deserts in an east-west overlap. Finally, mix it all together with a bi-seasonal rainfall pattern, with frontal winter precipitation and convective summer thunder storms arriving from different regions of the Pacific Ocean and providing life-sustaining rainfall. This unique and intricate blend of topography, location, and weather create an explosion of life found nowhere else on the planet.

This concept originated in 1943 when Natt N. Dodge referred to the Chiricahua Mountains as “a mountain island in a desert sea” in an Arizona Highways article. Nature writer Weldon Heald, who lived in the Chiricahua Mountains of southeastern Arizona, popularized the term. In his 1967 book, Sky Island, he demonstrated the concept by describing a drive from the town of Rodeo, New Mexico, in the western Chihuahuan desert, to a peak in the Chiricahua Mountains, 56 kilometers (35 miles) away and 1,700 meters (5,600 feet) higher in elevation. Ascending from the hot, arid desert, to grasslands, then to oak- pine woodland, pine forest, and finally to spruce-fir-aspen forest.

This region spans four states and two countries, covering a patchwork of protected and unprotected public and private lands. The majority of the Sky Island mountain ranges in the U.S. are part of the Coronado National Forest. In Mexico, the mountains and low desert valleys are a mixture of private ranches, ejitidos (communal farm plots) and Reserva Forestal National. The Sky Island region has approximately 65 isolated mountain ranges covering roughly 70,000 square miles overall. The U.S. Mexico borders splits this region nearly in half with 20,000 square miles in the United States.


Valley floors within the Sky Island region vary between 2,500 and 4,500 feet while the isolated mountain peaks rise 6,000 to 11,000 feet with temperatures dropping about 4 degrees Fahrenheit every 1000 feet.

Eight distinct biotic communities are recognized on the highest Sky Islands of Arizona: Desert Scrub, Desert Grassland, Oak-Grassland, Oak-Woodland, Chaparral, Pine-Oak Woodland, Pine Forest and Mixed Conifer Forest. These 8 communities encompass five of the world’s great biomes: Desert, Grassland, Mediterranean Woodland and Shrub land, Temperate Broad-leaf Forest, and Coniferous Forest. Not every Sky Island is high enough to sustain them all; many are lacking pine and mixed coniferous forest.

Moist air moves up from the Gulf of California in the summer and the North Pacific in the winter. When these air masses are forced up and over the mountains, water vapor con-denses, forming clouds and rain. The mountains pull the water from the sky and bring it back to the landscape where it creates washes that recharge the aquifers and supply riparian areas, bringing life to plants, animals and people as it moves to the valleys below. One of the unique aspects of this region is the mix of floristic affinities, the trees and plants of higher elevations are more characteristic of northern latitudes while the flora of the lower elevation has ties to the desert and mountains further south. It is the only group of sky islands on the planet straddling two major floristic and two faunal realms as well as three major climatic zones: Tropical, Subtropical, and Temperate.


The Madrean Sky Islands contain some of the most rugged and remote lands in the southwest and feature some of the highest levels of biodiversity in the world. The Sonoran portion of the Sky Islands is not as well known biologically speaking but the Arizona portion is amazingly diverse hosting species that draw from all directions, elevations and latitudes. Although some species show little genetic variation between mountain ranges, other species have evolved on these mountain islands. Like a bunch of separated terrariums, they serve as natural laboratories for the study of evolution because conditions differ from island to island.

More than half the bird species in North America are found here as well as, 29 bat species, over 3,500 species of plant, 150,000 invertebrate species and 104 species of mammals, the highest concentration of mammals in the United States.

Plants and animals of every shape, size, and specialty reside here. From familiar favorites like the giant Saguaro Cactus towering 60 feet above the earth “holding it’s breath” all day to conserve water, to the many species of tiny Talus Snail, found deep intalus crevices and leaf litter, only surfacing after it rains. Mexican Gray Wolf, Thick Billed Parrot, New Mexican Ridge Nosed Rattlesnake and Apache Trout are a few of the endangered species that live here and in recent years the Jaguar and Ocelot have returned. There are many other rare creatures found here, with names that capture our imagination like Tropical Soldier Fly, Santa Catalina Geometer Moth, Sonoran Tiger Salamander, and Elegant Trogon just to name a few. Several new species discoveries have been made such as the colorful Fire -Tailed Ground Snake, the Black Tailed Ringtail Dragonfly and a yet unnamed species of Bog Orchid. Bee, reptile, and ant diversity is unparalleled here, speaking volumes about the sub-tropical influences withinthe region.


The bi-national Madrean Archipelago or Sky Island region of the southwestern UnitedStates and northwestern Mexico is recognized for its unique biological diversity, naturalbeauty, and cultural heritage.

Today the most significant threats to the Sky Island Region are climate change, over-grazing, fire suppression, loss of predators, energy development, mining, and borderissues. Groups such as The Sky Island Alliance are working on both sides of the border to protect and restore the biodiversity and natural heritage of the Sky Islands. They work with volunteers, scientists, landowners, public officials, government agencies and over a hundred partner organizations to establish protected areas, restore healthy landscapes, and promote public appreciation of the region’s unique biological diversity. Their Madrean Archipelago Biodiversity Assessment (MABA) project is a groundbreaking effort to extend knowledge of animals and plants in the Sky Islands of Arizona and New Mexico southward into Sonora and Chihuahua, Mexico. The biodiversity in the Madrean Archipelago is recognized globally, but information about species distributions is critical to understanding and protecting biodiversity.

The Biodiversity and Management of the Madrean Archipelago Conference (known as the “Madrean Conference” or “MADCON”) is a regional event for sharing science and building collaboration and is part of a series that still shapes our understanding of the region through presentations given in 1994, 2004 and 2012. The conference is a dynamic opportunity for researchers, managers, and conservation practitioners to learn the latest science and translate it intopractical management approaches.

There is still so much to discover and learn about this region and with the very real threat of climate change there is no time to waste. Just as our magnificent Sky Islands connects mountain ranges, deserts, states, and even countries, successful conservation also requires connections. Not just across the physical and political landscape but most importantly conservation requires connection between people and the place they live. It’s good to know that there are so many working to foster these connections in order to restore and preserve the truly unique biodiversity of this region that is our home.


Aslan, Clare. “Celebrating the Sky Islands” Sonorensis – Arizona-Sonora Desert Muse-um: Celebrating the Sky Islands (2013)

Center For Biological Diversity

Coblentz, David. Riitters, Kurt H. A quantitative topographic analysis of the Sky Is-lands: a closer examination of the topography-biodiversity relationship in the MadreanArchipelago [Abstract]

Colodner Debbie. “Sky Island Geology.” Sonorensis – Arizona-Sonora Desert Museum:Celebrating the Sky Islands (2013)

Debano, Leonard H., et al. “Biodiversity and Management of the Madrean Archipela-go: The Sky Islands of Southwestern United States and Northwestern Mexico.” 1995,doi:10.2737/rm-gtr-264.

Koprowski, J.L., 2005, A Dearth of Data on the Mammals of the Madrean Archipelago:What We Think We Know and What We Actually Do Know in Connecting MountainIslands and Desert Seas: Biodiversity and Management of the Madrean Archipelago

II: United States Department of Agriculture, Forest Service, Rocky Mountain ResearchStation, Proceedings RMRS-P-36, p. 412-415.

Leary, Catie. “9 Sky Islands That Are Brimming with Endemic Species.” MNN – Moth-er Nature Network, Mother Nature Network, 31 May 2017,

Phillips, Steven J., et al. A Natural History of the Sonoran Desert. Arizona-Sonora Des-ert Museum Press, 2015.

Pociask, Stefan. “What Are Sky Mountains and Why Are They Important?” The Huffing-ton Post,, 5 May 2017,

Robbins, Ted. “Hotter, Drier Climate Moves Up Sky Islands’ Slopes.” NPR, NPR, 21July 2007,

Staff, Live Science. “Life’s Diversity Abounds in Madrean Sky Islands.”LiveScience, Purch, 12 Jan. 2011,

Skroch, Matt. “Sky Islands of North America: A Globally Unique and Threatened InlandArchipelago : Articles.”,

“Sky Island.”, 2 July 2015,

“Sky Island.” Wikipedia, Wikimedia Foundation, 10 Apr. 2018,

Van Devender, Thomas R., Deyo, Nick., Neeley, Jenny. “Exploring Biodiversity andConservation Opportunities in the Sky Island Region” Sonorensis – Arizona-SonoraDesert Museum: Celebrating the Sky Islands (2013)

Warshall, Peter, The Madrean Sky Island Archipelago: A Planetary Overview

The Madrean Sky Islands of the United States and Mexico map by Sky JacobsCatalina Mountains photo by Carrie Barcom

Citizen Science: City Nature Challenge 2021

The City Nature Challenge is a global initiative to document the world’s biodiversity (see How it got Started), particularly in urban areas. This event occurs in two parts:

Part 1- April 30-May 3
* Discover- explore to find a variety of species.
* Document- take a photo of each with your camera or smart phone.
* Share- upload your observations to iNaturalist.

Part 2- May 4-9
* Identify- help identify all of the project’s observations.

Join our project on iNaturalist here: City Nature Challenge 2021: Greater Tucson Area

This is the first year Tucson is participating and we, the Pima County Master Naturalists, are the main organizers. Why are we doing this? The benefits to our city are numerous!

  • Get people outside interacting with nature to foster a connection with and care for local biodiversity.
  • Provide people an opportunity to be part of a citizen science project.
  • Build community around a shared love of nature.
  • Introduce people to iNaturalist as a tool to document and identify organisms.
  • Engage schools in project participation and related lessons to have more children learning about their local natural environment.
  • Develop a database of observations that are “Research Grade” so they can be used by scientists.
  • Increase the visibility of PCMN in the community.
  • Develop and strengthen partnerships with other organizations.

Photos from Sweetwater Wetlands, Tucson AZ: Deb Petrich (C1)