is a long-term visual storytelling project by Luke Swenson (Documentary Photographer) and Jack Dash (Naturalist and Writer). Since 2017, we have been working to better understand the Arizona-Sonora Borderlands alongside ecologists, cattle ranchers, humanitarian aid workers, migrants, hunters, ex-border patrol agents, and indigenous community members. This project will ultimately bring together hundreds of original film photographs, oral history interviews, botanical specimens, historical images, and found objects; creating a living archive dedicated to this remote 42-mile section of the US-Mexico border.
Opuntia santa-rita (Santa Rita prickly pear) growing from exposed rock along a canyon running south through Cumero Mountain. This species is known only from Southern Arizona and Northern Sonora.
Archeological evidence suggests that the Atascosa Highlands were part of an overlapping boundary between the Hohokam and Trincheras cultures, long before the existence of the United States and Mexico.
The lack of significant perennial water sources suggests that indigenous communities probably had little in the way of permanent settlements throughout the Atascosa Highlands, but that the region would have been used for hunting and gathering, as well as movement between villages.
Anthropomorphic figures - oftentimes depicted with outstretched hands and fingers, or holding a bow and arrow - as well as abstract curvilinear, and representational designs depicting flora and fauna are some of the most common stylistic elements seen in Hohokam petroglyphs; thought to date back to A.D. 600 to 1450.
Hohokam petroglyphs at the peak of Cumero Mountain.
Hohokam bedrock mortars below Cumero Mountain.
Agave harvesting knife, courtesy of the Tubac Presidio State Historic Park and Museum.
Worked stone sherds, courtesy of the Tubac Presidio State Historic Park and Museum.
Mano and metate, courtesy of the Tubac Presidio State Historic Park and Museum.
The grasslands of the Pajarito Mountains following a monsoon downpour. These summer rains spur the growth of heat and humidity loving plants that give the region a distinctively subtropical feel. The Arizona-Sonora Borderlands are in the midst of the most extreme long-term drought recorded in the region in 1,200 years which makes these monsoons essential to stabilizing drought-stricken ecosystems.
Jim Verrier surveying the hills above Holden Canyon in the Pajarito Mountains. Jim is a researcher and the Nursery Director of the Tucson based non-profit native plant nursery Desert Survivors, where he manages cultivation of native species for conservation and urban landscaping.
Myriopteris lindheimeri (fairy swords, hierba de la pena) in the Pajarito Mountains. This diminutive fern can form dense clonal colonies on shaded slopes.
Echinargus isola (Rearkirt's blue) nectaring on Heliomeris longifolia (long-leaf false goldeneye). These tiny butterflies have a wingspan of less than an inch but can occur in vast numbers following abundant monsoon rains.
Coryphantha recurvata (Santa Cruz beehive cactus) at upper Alamo Canyon in the Pajarito Mountains. The only known locality for this small cactus in the United States, is in the Atascosa Highlands, where it grows on rocky ledges or tucked among bunchgrasses. Historical slide photograph courtesy of Frank Reichenbacher.
Ecologist and Ethnobotanist, Gary Nabhan at his home in Patagonia, AZ. Gary has been instrumental in establishing the Wild Chile Botanical Area in the Tumacacori Mountains to preserve populations of Capsicum annuum var. glabriusculum (chiltepin). These plants are the wild progenitors of dozens of chile cultivars including Bell, Anaheim, Serrano, and Jalapeno peppers.
Chiltepin is the port of entry, or the gateway drug to get people excited about the whole area. It's possibly...the northernmost wild Chile population that we know of in North America.
A rugged drainage hosts a previously undocumented population of Chiltepins a few hundred yards north of the Arizona-Sonora Boundary. These wild chili peppers - growing near the edge of their range - possess unique traits which could help plant breeders increase the resiliency of cultivated pepper plants
The fruits of chiltepins are relished by bird species who are unperturbed by the intense spice of these small peppers. This makes chiltepins an important seasonal food source for native avian fauna who spread the seeds to favorable locations to germinate.
Rancher, Sue Chilton harvests chiltepins growing in her garden near Arivaca, Arizona. These plants were grown from seed collected in the mountains nearby and easily withstand the extremes of heat and cold experienced in the area.
Sycamore Canyon in the Pajarito Mountains. This canyon is an essential migratory corridor for birds and mammals, and hosts plant species that occur nowhere else in the United States.
Mimosa grahamii (Graham’s mimosa) growing in Sycamore Canyon.
Mimosa grahamii (Graham’s mimosa)
Frank Reichenbacher's floral checklist from a trip to Sycamore Canyon in the Pajarito Mountains in September, 1980. Checklists such as this can help botanists compare changes in the species demographics of a given locality and are essential to developing an understanding of how ecosystems around us are changing over time.
Quercus emoryi (Emory oak) and Juglans major (black walnut) growing together at the entrance to Sycamore Canyon in the Pajarito Mountains. In 1946 the botanist Leslie Goodding referenced this exact oak tree in an article for the New York Botanical Garden writing, "if you wish to explore...you will probably park your car in the shade of a widely spreading Emory oak."
Graptopetalum bartramii (Patagonia Mountains stonecrop) can occur as individual plants, or in small populations perched precariously on rocky crevices in the shade of riparian canyons growing just a few inches across. The flowers of this small succulent bloom following the summer monsoons and are pollinated by small flies. Seeds are thought to wash down canyon in seasonal floods which leads to isolated populations spread out from one another with limited ability to cross pollinate. This pattern means that the die off of a single shaded tree, or the misplaced boot heel of a passing hiker could be the end of an entire population.
Frank Reichenbacher's observation and collection journal from July 26th - October 19th, 1980.
Frank Reichenbacher's observation and collection journal from April 24th, 1989 - April 27th, 1993.
Historical slide photograph of Penstemon discolor (Catalina beardtongue) courtesy of Frank Reichenbacher.
Frank Reichenbacher processing botanical specimens on a folding table behind the trunk of his Nissan Xterra. For nearly 40 years, Frank has observed and recorded a single population of Penstemon discolor (Catalina beardtongue) just south of Corral Nuevo in the Atascosa Mountains.
The Penstemon discolor (Catalina beardtongue) population in the Atascosa Mountains is located approximately 90 miles or 145 kilometers from the nearest known population. Studies of these isolated individuals may help botanists uncover the evolutionary and biogeographic history of this uncommon species.
Agave parviflora (small-flowered agave) a state-listed rare plant known only from a handful of localities in Southern Arizona and Northern Sonora. This uncommon species occurs in isolated colonies separated from each other by miles. The yellow blooms are pollinated by native bee species, and the flower stalks are sometimes browsed by deer and cattle.
Agave parviflora (small-flowered agave) habitat in the Pajarito Mountains. This species doesn't compete well with other plants and prefers to grow on thin, rocky soils, which prevent grasses and shrubs from growing too densely. Agave parviflora was first described from a collection made in 1855 by Arthur Schott, a botanist with the US-Mexico Boundary Survey.
Historical slide photograph of Agave parviflora (small-flowered agave) habitat courtesy of Frank Reichenbacher.
Historical slide photograph of Agave parviflora (small-flowered agave) courtesy of Frank Reichenbacher.
Robert Villa observing a population of Agave parviflora (Small-flowered agave) hidden among tall grasses east of Atascosa Peak. Villa is a naturalist, research associate, and Community Outreach Assistant at the University of Arizona's Desert Laboratory on Tumamoc Hill in Tucson, Arizona.
Robert stops to make a note in his field journal on a trip to Sycamore Canyon in the Pajarito Mountains. In addition to his work documenting the flora and herpetofauna of the Sonoran Desert region, Villa is president of the Tucson Herpetological Society. He is most well known for helping raise awareness for the unsustainable, and inhumane use of Bufo alvarius (Sonoran Desert toad) venom as a psychotropic substance.
Robert Villa holding a Diadophis punctatus (ring-necked snake). This species occurs across a broad swath of North America and thrives in the riparian canyons of the Sky Island region.
Historical slide photograph of Oxybelis aeneus (Mexican vine snake) courtesy of Frank Reichenbacher. This species is extremely rare in the United States and is an indicator of the subtropical influence on the flora and fauna of the Atascosa Highlands.
Thamnophis cryptosis (black-necked gartersnake) sheltering in boulders near the edge of Sycamore Canyon in the Pajarito Mountains.
Thamnophis cryptosis (black-necked gartersnake) dipping into a seasonal stream in Sycamore Canyon in the Pajarito Mountains. These snakes occupy a variety of habitats and elevations but are most often found near springs and streams.
Looking west from Atascosa Lookout towards Atascosa Peak.
Lagascea decipiens (doll's head) blooming at the base of Cumero Mountain. This species is only found in the United States in a small portion of Southern Arizona.
A steep canyon running towards the border from Alto Shumaker Tank in the Pajarito Mountains.
Wendy Hodgson is a Senior Research Botanist at Desert Botanical Garden, and one of the world's foremost experts on the genus Agave. Here she explains the history of an agave cultivar on the grounds of the Garden. Agave cultivars like this one are species that were intentionally selected for and cultivated by indigenous people as a source of food and/or fiber.
Entrance to the Ahearn Desert Conservation Laboratory at Desert Botanical Garden in Phoenix, Arizona. This state of the art research facility is home to a crucial seed bank for Sonoran Desert plants, where Garden scientists are working to protect species from changing environmental conditions and human impact.
Greenhouses at Desert Botanical Garden in Phoenix, Arizona. The Garden houses a collection of around 400 rare, threatened or endangered desert plant species with a focus on cacti and succulents. Collections like these ensure that the genetic lineages of rare plants survive so that they can be studied and cultivated for conservation purposes.
Collection and observation journal of Wendy Hodgson detailing one of her first trips to the Atascosa Highlands in September, 1985.
Knife marks left on a Ferocactus wislizeni (fishhook barrel cactus) from the harvesting of two ribs for processing into botanical specimens. These ribs are later dried and pressed, before being deposited in an herbarium. Because of the difficulty in collecting cacti and succulents these plants are generally underrepresented in herbaria.
Ferocactus wislizeni (fishhook barrel cactus)
Wendy Hodgson observing and recording information about a flowering Agave palmeri (Palmer's agave) prior to collecting a specimen.
Wendy Hodgson overlooking the grasslands north of Cerro Del Fresnal.
Wendy Hodgson returning to her Desert Botanical Garden vehicle with an Agave palmeri (Palmer's agave) specimen for the herbarium.
Botanical specimens being prepared for long-term storage at Desert Botanical Garden's herbarium. Plants are pressed and dried, and treated with preservatives, before being glued to herbarium sheets with a label and photographs. They are then digitally catalogued and officially accessioned into the herbarium's collection.
Folders of botanical specimens ready for processing in the herbarium.
Wendy explaining the proper collection procedure for cacti and agave while on a tour of the herbarium at Desert Botanical Garden.
Wendy Hodgson observing individuals of Mammillaria grahamii (fishhook pincushion cactus) and Mammillaria macdougallii (pancake pincushion cactus). These plants thrive in the rhyolitic cliffs which rise above the surrounding grasslands.
Mammillaria grahamii (fishhook pincushion cactus) at Desert Botanical Garden.
A butterfly in the genus Asterocampa lands on the spiny branch of a chain fruit cholla at the base of Cumero mountain. "Cumero" is a Spanish word for the tree known in English as Celtis reticulata (canyon hackberry) which is the food source for the larvae of these butterflies.
Cylindropuntia fulgida (chain fruit cholla) cutting ready to be pressed and processed into an herbarium specimen. The grasses growing around the cutting are primarily non-native species.
Light spills across the dried up pools at the narrows in Sycamore Canyon during extreme drought. Seasonal pools like these have historically provided important habitats for amphibians and reptiles in the Atascosas such as Rana chiricahuensis (Chiricahua leopard frog). Herpetofauna are under increasing pressure from ongoing drought, competition from introduced species like Lithobates catesbeianus (American bullfrog), and chytridiomycosis, a fungal disease that has dramatically impacted frog populations globally. Efforts are underway by the Arizona Game and Fish Department to eradicate invasive populations of bullfrogs, and support the reintroduction of the native leopard frog here in Sycamore Canyon.
An Arizona Game and Fish Department vehicle parked along Ruby Road where it crosses Alamo Canyon. Game and Fish is tasked with the monitoring and conservation of native species as well as control of hunting in the state of Arizona.
Tom Jones, Amphibians and Reptiles Program Manager with Arizona Game and Fish scans for Lithobates chiricahuensis (Chiricahua leaopard frog) at Peña Blanca Spring. This small pool is man-made, fed by a small, underground pipe that runs from the nearby spring. An obstruction of that single pipe, could easily result in the evaporation of this critical habitat for herpetofauna. The Atascosa Highlands were historically home to Lithobates tarahumarae (Tarahumara frog), a species that has now been extirpated from the United States entirely.
Tom Jones holds the desiccated remains of a snake killed by traffic along Summit Motorway south of Atascosa Peak. Increased traffic on these roadways from recreationists, migrants, smugglers, and border patrol can negatively impact the herpetofauna of the Atascosa Highlands who have to cross these roadways or use them to sun themselves.
Looking east towards Atascosa and Ramanote Peaks from Ruby Road. The grasslands of the Atascosa Highlands have been altered by centuries of cattle grazing and fire suppression. The rolling plains are dotted with trees and shrubs that are unpalatable to livestock and which have thrived in the absence of fire.
Pennisetum ciliare (buffelgrass) is a non-native grass, which was intentionally introduced to Arizona in the 1930's and has gone on to become one of the most destructive invasive plants in the Borderlands. Buffelgrass contributes to biodiversity loss and encourages catastrophic fires which damage fragile desert ecosystems.
Pennisetum ciliare (buffelgrass)
Quercus rugosa (netleaf oak) is one of the less common oak species found in the Atascosa Highlands. The population of netleaf oak in Sycamore Canyon is growing at the lowest known elevation for this species.
Grassland and Oak woodland come together in a side drainage of Pena Blanca Canyon. Though ecosystems are often split and defined by elevational range, the complex topography of the Atascosa Highlands brings together different habitats which increases the local biodiversity present within a given area.
Water has carved ravines in a rubble flow that comes down from a recently constructed section of border wall in the Pajarito Mountains.
The remnants of oaks buried by the waste rock from border wall construction and road building in the Pajarito Mountains.
Yucca "schottii" (mountain yucca) near the mouth of Sycamore Canyon in the Pajarito Mountains stands nearly 8-10' tall. This tree-like yucca is found in the wooded canyons of sky island mountain ranges along the US-Mexico boundary.
Yucca "schottii" (mountain yucca) partially buried in debris from border wall construction near USFS road 222.
Pseudognaphalium leucocephalum (white rabbit-tobacco)
Fouquieria splendens (ocotillo)
Opuntia chlorotica (pancake prickly pear)
Pinus discolor (border pine)
Agave palmeri (Palmer's agave)
Elionurus barbiculmis (wooly balsamscale)
Newly constructed sections of border wall running across the Altar Valley, seen through a grove of Fouquieria splendens (ocotillo) at the base of Cumero Mountain. The recent push to build border wall in the Atascosas continued up until the close of the Trump Administration on January 19th, 2021.

Information

The Atascosa Highlands are an area of incredible biological diversity located within one of the most ecologically rich regions on the planet. While these mountains have been inhabited for thousands of years, the last few centuries of human activity have had a profound effect on this stretch of the US-Mexico border, making it essential to document the ecology of the region now.

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Acknowledgements

THIS PROJECT WAS FUNDED THROUGH A GRANT FROM THE KALLIOPEIA FOUNDATION WITH ADDITIONAL SUPPORT FROM THE WITTLIFF COLLECTIONS. FILM DEVELOPMENT BY BLUE MOON CAMERA AND MACHINE.
SOUND DESIGN AND MUSIC BY GUS TOMIZUKA AND PATO CORONADO AT TRANSITORY TAPES, AN AUDIO-VISUAL COLLECTIVE BASED IN THE UNITED STATES AND MEXICO.
INTERACTIVE AND VISUAL DESIGN BY DEVIN JACOVIELLO. DEVELOPED BY BRANDON CHANG. STRUCTURED CONTENT POWERED BY Sanity.io.
project by: l.swenson & J.Dash
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