Tucson Fire prepares for wildfire season after heavy rains fuel grass growth

Tucson residents are heading toward another wildfire season with an unusual concern on the ground: heavy rain has produced thick stands of invasive grass that could become highly flammable as the weather dries. Tucson Fire Department crews are already surveying areas where vegetation could help a fire spread, clearing brush and creating firebreaks before summer conditions arrive. Officials are also asking homeowners to keep defensible space around their properties and report hazardous vegetation through city and county online forms.

The recent rainfall has made the Tucson area look greener, but that growth may create more fuel later in the year. Invasive grasses can dry quickly, catch fire from a small ignition source and carry flames across open land. Tucson Fire Deputy Chief of Operations Antonio Canizales said the department expects the vegetation produced by the wet year to create challenges during the next fire season. Crews are using drones to locate areas of concern and reviewing weather patterns and known hazards throughout the year, rather than waiting for red flag conditions to begin preparation.

That planning includes coordination with fire agencies in surrounding communities. Regional cooperation allows departments to share resources and strengthen their response if a fire moves across jurisdictional boundaries. For property owners, firefighters say basic prevention can reduce the amount of available fuel near homes. Maintaining defensible space, clearing vegetation and notifying officials about dangerous growth are among the steps residents can take before extreme heat and dry conditions make those tasks more difficult.

The concern is not limited to the first hours of a wildfire. Research connected to a fire north of Tucson shows that burned land can remain vulnerable long after flames are contained. The March 2025 Saddlebrooke Fire was stopped within two days after burning more than 200 acres of State Trust Land leased for grazing by Falcon Valley Ranch, co owned by Grant Wilson and his sister, Jennifer Wilson. The fire moved toward the ranch during calving season, when young cattle could be difficult to move, and wind pushed flames toward the ranch headquarters and Wilson’s home.

The immediate threat passed, but the burned landscape faced a different set of dangers. When an Arizona State University research team visited the area in November 2025, heavy rain had washed soil from portions of the burn scar. With much of the vegetation gone, water had cut deep channels through the ground. Trees and cacti stood as blackened remnants, while only limited grasses had returned. Researchers said burned soil can lose its structure and remain susceptible to wind erosion, flooding, debris flows and shallow landslides for years. Those effects can damage property, roads, water supplies and other infrastructure.

The Saddlebrooke Fire also illustrates why invasive grasses are a growing concern in Southern Arizona. Desert plants historically stood far enough apart that many lightning caused fires had difficulty spreading. Invasive grasses now fill the spaces between native plants, creating a continuous layer of fuel. Lehmann lovegrass, one species found at the burn site, was introduced from South Africa to Arizona in the 1930s to help control erosion and provide forage for livestock. Once established, invasive grasses can return quickly after fire and compete with native plants, reinforcing a cycle of repeated burning.

That cycle is intensified by drought and rising temperatures linked to climate change. The ASU team is investigating whether fungi could provide a more affordable and environmentally sustainable way to protect soil after a fire. The researchers are studying mycelium, the underground, rootlike network that makes up the main body of a fungus. Their work focuses on oyster mushroom fungus, Pleurotus ostreatus, whose mycelium can grow around soil particles and potentially bind them together.

The project is part of Assistant Professor Emmanuel Salifu’s work in biogeotechnics, an emerging field that examines how living organisms can help stabilize soil, remove pollution and repair infrastructure. Civil engineering student Henry Nakaana began the wildfire recovery project as a first year student, and environmental engineering student Lune Martin later joined the effort. Nakaana became interested in the question of how to restore vegetation quickly for ranchers whose grazing land has burned, while Martin brought experience from summer work restoring prairies, removing invasive grasses and conducting prescribed burns in Texas. Both students emphasized the importance of soil, especially in a desert where recovery can be slow.

Current post fire erosion controls often rely on physical barriers that are expensive, labor intensive, slow to install and difficult to maintain. The ASU researchers are exploring whether fungal networks could offer a natural alternative or complement to those methods. Their work remains in development, but Russell Benford, a policy and research adviser with the Arizona Department of Forestry and Fire Management, said the approach could address a major gap in post fire response. He identified soil erosion, debris flows and catastrophic flooding as some of the most serious threats after a fire.

For Tucson and nearby communities, the research underscores why wildfire preparation must include both prevention and recovery. Fire crews are working now to reduce fuel before grass dries, while researchers are looking at ways to limit the damage left behind when vegetation is gone. Residents can support those efforts by maintaining clear space around homes and reporting dangerous growth. The combination of wet season vegetation, invasive grasses and vulnerable desert soils means the risks may continue well beyond the day a fire starts.