Overview
The Arizona hedgehog cactus (Echinocereus arizonicus subsp. arizonicus) is a dark-green succulent plant with brilliant red claret-cup flowers. Plants are found scattered on open rocky slopes, steep-walled canyons, and cracks within granite boulder-pile ridges (Arizona Rare Plant Committee 2000) within chaparral and oak woodlands. Located in central Arizona, predominantly on lands administered by the U.S. Forest Service, the cactus occupies a narrow geographic range between the towns of Superior and Globe in Pinal and Gila counties.
The Arizona hedgehog cactus was listed as an endangered variety (Echinocereus triglochidiatus var. arizonicus) on October 25, 1979 (USFWS 1979). Designation of critical habitat was not deemed prudent because it would increase threats to the plant from illegal collection. At the time of listing, accurate identification was difficult and the taxonomic status of this entity had not been completely resolved; multiple varieties of Echinocereus triglochidiatus were taxonomically difficult to separate. The final listing rule states: “Different varieties within the species Echinocereus triglochidiatus intergrade extensively with one another. Mixed populations showing extensive variation but with some affinities toward var. arizonicus are not to be considered classical var. arizonicus and therefore will not be subject to the protection and restrictions of the Endangered Species Act...until further data is available only known populations of this variety will be subject to the Endangered Species Act.” While the wording "known populations" has resulted in confusion, specifically in regards to federally proposed actions, the cactus is listed throughout its entire range wherever found.
The cactus is distributed over an estimated 141,747 acres of interior chaparral, and upland Sonoran desert habitat. Total abundance of the rangewide population and population trends are unknown. Direct access to a large portion of the species range is limited due to the rugged topography and remoteness of its habitat making surveys difficult to conduct. However, based on surveys that have been completed, there were over 7,000 documented Arizona hedgehog cacti as of January 2021 (AZGFD HDMS 2019). In the summer of 2021, two large wildfires burned through more than 181,000 acres of its habitat. About 1,578 Arizona hedgehog cacti were documented in the fire scar and their status is currently being assessed. As more information becomes available, the estimated abundance will be updated.
Threats to the Arizona hedgehog cactus include habitat loss and fragmentation from activities associated with mining, mineral exploration, road construction, power-line construction and utility corridors; illegal collection; habitat disturbance from livestock grazing; and climate change climate change
Climate change includes both global warming driven by human-induced emissions of greenhouse gases and the resulting large-scale shifts in weather patterns. Though there have been previous periods of climatic change, since the mid-20th century humans have had an unprecedented impact on Earth's climate system and caused change on a global scale.
Learn more about climate change that influences increased temperatures and reduced precipitation. Additional threats to the cactus include wildfire, herbicide and pesticide application, and insect infestation (USFWS 1979, Fletcher 1984, Cedar Creek 1996).
Identification Numbers
Characteristics
Habitat
The Arizona hedgehog cactus is found from 3,400 to 5,300 feet (1036 to 1615 m) in the ecotone of Interior Chaparral, Madrean Evergreen Woodland, and Upland Sonoran Desert plant communities (Brown 1982). The cactus is scattered on open rocky slopes of 20 to 90 degrees, boulder outcrops, exposed bedrock, and steep-fissured cliffs (Fletcher 1984). The cactus roots invade crevices, fissures, and narrow areas between boulders or rock fields that exhibit sufficient fracturing or rock interstices for establishment. Soil, where available may be sandy, shallow, and cobbly, providing the roots with the necessary anchoring medium, periodic moisture, and shelter from high temperatures. The cactus typically grows on north, south, and southeast facing slopes.
Geography
At the time of the listing, the Arizona hedgehog cactus was only known from the general vicinity of the type locality, a limited area along the U.S. 60 Highway that extended between the towns of Miami and Superior in central Arizona (Fletcher 1984). Surveys and other investigations resulted in a better understanding of its distribution. Currently, the known range of the Arizona hedgehog cactus is a narrow geographic area between Superior and Globe in Gila and Pinal counties in central Arizona. Within this range, the cactus is distributed from the Superstition Wilderness area south to Devils Canyon, east along US 60 to Top of the World, and south to the Pinal Mountains. There is also a small population that occurs on the Mescal Mountains.
The Globe Ranger District on the Tonto NF manages over 90 percent of the known occupied habitat of Arizona hedgehog cactus. The remainder of occupied habitat occurs on land administered by the Bureau of Land Management (BLM), Arizona State Trust Land, and privately owned lands. Based on its known distribution and potential habitat, the estimated range of the Arizona hedgehog cactus is approximately 141,747 acres.