After the hottest summer on record in the U.S., the value of a landscape with robust tree cover is hard to argue against. Trees keep cities livable, particularly in the desert Southwest, but getting the science of desert tree care into everyday practice takes more than the science itself.

Over four years, two teams from the University of Arizona College of Architecture, Planning and Landscape Architecture, or CAPLA, worked on the same challenge from different perspectives: the science of keeping desert trees alive, and the gap between that science and what people actually believe about tree care. Their efforts earned two national awards from the American Society of Landscape Architects, or ASLA.

The first team studied how to keep young desert trees alive on less water. In 2024, master of landscape architecture students Annalise Hummel, Christian Aguilar Murrieta and Cordell Lee won a National ASLA Student Award in Research for "Smart Tree Watering in Southern Arizona's Urban Environment."

This year, Master of Landscape Architecture students Ashley Zahri Danforth, Esmeralda Rubi Carrasco and Xavier Fernandez, and Bachelor of Landscape Architecture students Robin Tittelbaugh and Danielle Covey, won a National ASLA Student Award in Communications. Their project, "Growing Impact: Advancing Knowledge of Urban Desert Tree Care," was honored at the September 2026 ASLA annual conference in Los Angeles.

Image

Where good advice goes wrong

Carrasco, who holds a doctorate in business and was recently admitted to the Horticultural Research Institute's selective Leadership Fellows program, said common tree-care misconceptions come from good advice getting simplified over time. 

“‘Do not overwater’ or ‘do not over-prune’ can easily turn into blanket rules, even though tree care depends on the species, the site, the soil and what the tree is actually doing," she said.

In the desert, how and where you water matters as much as how much, Carrasco said. 

"Deep, less frequent watering encourages a stronger root system, while constantly watering right around the trunk can create other problems." Pruning requires similar nuance, she said. "Young trees need time to establish, and you definitely don’t want to over-prune them, but that doesn’t mean they should be left alone. Early structural pruning can help guide the tree as it grows."

Taking the science to the public

To address common tree-care misunderstandings at scale, the team designed and conducted five workshops and a series of hands-on sessions at the Campus Agricultural Center and on the university’s main campus. 

More than 200 people attended, among them landscape company owners, nursery professionals, arborists, city and county staff, students and garden club members. The team also offered webinars with the U.S. Environmental Protection Agency, the City of Tucson and Pima County, and produced training videos and printed guides.

For Fernandez, a third-year master's student who led the data and imaging related to the project, the value was in finding other local people and organizations using their skills and resources to achieve similar goals, such as staff from Tucson Water's Storm to Shade program. 

“The overlap between us was immediate,” he said. “Once we realized we were both doing data modeling, we both were like, ‘Oh good, we're not alone in this!’ We were able to compare notes."

Danforth, the team leader and a two-time graduate of the U of A who now works as a landscape designer with Kimley-Horn, said watching connections form was among the best parts of the project. 

“I loved when people from Tucson businesses and local government would say, ‘You're doing that too?’” she said. “You could see they appreciated discovering that someone with the same goals was doing things slightly differently, and that those differences were worth learning from.” — Ashley Danforth, MLA graduate student

A guidebook for the Southwest

The team’s capstone deliverable was the “Guidebook on Tree Health and Maintenance for Climate Adaptation in the U.S. Southwest”, which is expected to be published in the Arizona Department of Forestry and Fire Management public resource library.

Faculty advisors from five disciplines at the U of A, along with two colleagues at Arizona State University, guided the project, which was funded by a Regents' Grant from the Arizona Board of Regents, the National Science Foundation, the Arizona Department of Forestry and Fire Management and The Nature Conservancy.

Together, the two teams’ work offers a fuller picture of what it takes to keep a desert city green: not just knowing how to help trees survive the heat, but making sure that knowledge reaches the people planting, watering and pruning them.