Guidelines for a Pleasant Visit-Information Release-History

Information Release ( *updated 6/23/2016 )

SITE: Boyce Thompson Arboretum is 55 miles east of Phoenix, in the Arizona Upland division of the Sonoran Desert. It is located near U.S. Highway 60 milepost #223 on the south side of the road, just west of Superior, in Pinal County. The Arboretum is nestled against the base of the 4400-feet-high Picketpost Mountain. Elevation in the gardens is 2,400 feet and is generally a few degrees cooler than the Phoenix area.
GPS Coordinates N 33.28094*,W 111.16135* US-AZ mapcode MC3.WC4

PURPOSE: The purpose of the Boyce Thompson Arboretum is to instill in people an appreciation of plants through the fostering of educational, recreational, research and conservation opportunities associated with the world’s arid land plants. An Arboretum is an area that focuses on trees and other woody plants. Although the Colonel’s original intent was to plant trees (hence the name, Arboretum), he soon realized that all types of plants from around the world should be included.
The Arboretum was founded April 1, 1924, incorporated as Arizona’s first non-profit research institution on October 5, 1927, and officially dedicated and opened to the public on April 6 1929.
The Arboretum is cooperatively managed by the non-profit 501(c)(3) Boyce Thompson Southwestern Arboretum, Inc., University of Arizona, and Arizona State ParksIt is accredited by the American Alliance of Museums.

PUBLIC FACILITIES: The Arboretum is open daily year-round, except Dec. 25. During Fall and Winter months, hours our 8 a.m. to 5 p.m. (last admission at 4 p.m.). Summer hours (May, June, July, August, September) are 6 a.m. to 3 p.m. (last admission at 2 p.m.) Daily admission is $12.50 for adults and $5 for ages 5-12. Children under 5 years of age are admitted free.
The Arboretum Visitor Center is located at the edge of the entry parking lot just off Highway 60. The Visitor Center contains a bookstore/giftshop, plant sales, administrative offices, greenhouse, art gallery, and patios.
The historic Smith Building, located a short distance downhill, was the original Visitor Center. Erected in 1926, it is constructed of rhyolite, a native stone quarried directly across Highway 60. It encompasses an Interpretive Center with museum exhibits and displays. Two public greenhouses attached to the Smith Building display living specimens of cacti and succulent plants from around the world.
The chief attraction at the Arboretum is the system of nature trails, with over three miles of combined length that weave through the Arboretum. In walking these trails one will discover our cactus and demonstration gardens, as well as exhibits recreating various deserts of the world, such as Australia, South America and South Africa.
The Picnic Area is adjacent to Queen Creek and about 100 yards southeast of the Visitor Center. Mature trees provide shaded throughout the picnic area. Picnic tables and charcoal grills are available for use. (Propane-only fire restrictions often go into effect in the summer). A Demonstration Garden is west of the Picnic Area. It exemplifies use of drought-tolerant plants for landscaping, and demonstrates water-harvesting methods and irrigation techniques.

EDUCATIONAL GROUP LECTURES AND TOURS: Most visitors take two or three hours to explore the Arboretum using maps and trail guides available at the Visitor Center. Guided tours can be arranged for groups of at least 20 or more people, provided sufficient notice is given. Appointments may be arranged by phone at 520.689.2723, or by email at
The public may visit at any time in small groups. However, organized groups and classes are asked not to come without an appointment, since the facilities (including restrooms, parking lots, trails, etc.) can accommodate only the number of groups and classes that are ordinarily scheduled. Adult supervisors and an orientation session are required for classes below college or university level.
The Arboretum offers a series of public events each year, most of them included with daily admission. Our annual Bye-bye Buzzards Day is in September; seasonal Plant Sales events are in October and March (though plants are sold year round); and November has both a Live Music Festival and our Fall Color Festival on Thanksgiving Weekend. Australia Day is in January; and the annual Welcome Back Buzzards festival is in mid-March. Seasonal weekend tours during fall, winter, and spring include bird-walks, the Plants of the Bible Lands tour, and the Edible/Medicinal Plants of the Desert walk. Summer nature walks include lizard, butterfly, and dragonfly walks. For complete event details visit our website or call the recorded message phone: 520.689.2811
Annual membership is a great way to support the Arboretum. Membership levels start as low as $60 and include a full year’s access to the Arboretum with extra guest passes for friends or family. For complete information about benefits of membership call Lori at 520-609-7873 or email
Read more complete information about benefits of membership


Although the public is currently restricted to about 100 acres of the Arboretum, the total acreage is closer to 392. Bordered on all sides by the Tonto National Forest, visitors get a true sense of escaping the city and being transported to a wilder setting.
A storage reservoir designed to hold 3,680,000 gallons (10-acre feet) of water for irrigation was constructed in 1925. This was later named to honor Judge Charles F. Ayer, legal advisor to Colonel Thompson, who (with the Colonel and Attorney Edward W. Rice of Globe) was an original incorporator of the Arboretum. Ayer Lake is filled by means of pumps: one lifts water from Queen Creek over Magma Ridge and the other pumps from a well approximately ½ mile west of the Arboretum.
The early work at the Arboretum in soil-retention by plant roots was instrumental in development of the U. S. Soil Conservation Service (SCS). The original Arboretum Director, Franklin J. Crider, left to become the first head of the Plant Materials Section of the SCS. As such he was one of the important founding fathers of the Soil Conservation Service. His original program was a cooperative one headquartered at the Arboretum and consisting of an interlocking project jointly accomplished by the Arboretum, the Forest Service, the Bureau of Indian Affairs, and the Civilian Conservation Corps.
During World War II, the Arboretum distributed young cork oaks widely in the Southwest as a measure of emergency preparedness when the Nazi-Fascist interests that threatened the world’s cork supply.
Weather observations at the Arboretum, including precipitation and high and low temperatures, have been faithfully recorded daily for over 75 years. Rainfall averages 17.0 inches per year, with two thirds in winter and one third in summer. Since 1965 guest quarters have been maintained, housing a variety of visiting scientists, researchers, lecturers and special guests. These scientists bring a wide range of studies appropriate to desert surroundings to the Arboretum. The Arboretum can provide housing, research facilities and logistic support for studies.
To inquire about this call 520.609.7821.
Since the 1960s, Arboretum bird checklists have been made available to visitors. Because of the Arboretum’s diverse habitats 270 species of birds have been recorded here, including many rare and unusual migrants. Checklists for birds, mammals, reptiles, amphibians and wildflowers may be requested at the visitor center.

William Boyce Thompson was born at Virginia City, Montana on May 13, 1869. He attended the School of Mines a Columbia University, becoming a mining engineer. He created a fortune by studying mines and selecting the most promising for development and investment. He was the founder and first president of Inspiration Consolidated Copper Company at Globe-Miami, Arizona and Magma Copper Company at Superior, Arizona.
Thompson received the honorary title of “Colonel” when he led a Red Cross expedition in 1917 to bring medical supplies, humanitarian assistance, comfort and advice to the Russian people who had just overthrown the Czar and who were still fighting Germany in the eastern theatre during World War I. He reached St. Petersburg after a long trip through arid parts of Asia. During this trip he became impressed with mankind’s dependence on plants. He was struck by the fact that all food comes originally from plants. Although he encountered starvation and malnutrition, he was impressed by the many uses made of the rather scarce plants. During the trip he thought of creating an arid land arboretum where plants from the world’s deserts could be brought together, catalogued, and their uses inventoried and their seeds distributed. Colonel Thompson died on June 27, 1930. The Arizona Legislature stated that it was “profoundly appreciative” of the Boyce Thompson Southwestern Arboretum as a “scientific institution for the purpose of experimentation and research in the matter of native vegetation of the state and the Southwest.”

Updated: 6/23/2016