Queen butterfly (Danaus gilippus). Photo Courtesy of Bruce Taubert.

Author: Kelli Larson, Professor of Geography and Sustainability at ASU

Kelli Larson is a Professor at Arizona State University who moved to the Sonoran Desert in 2005 and regularly engages students in her research. Her work focuses on how people interact with nature and manage urban landscapes and the environment. When she is not working, Kelli practices yoga and loves to hike, paddle, and otherwise explore nature and different places throughout Arizona and elsewhere. She also enjoys spending time with her dogs, going to plays, and cooking. You can learn more about Kelli or contact her through ASU.

From forested mountains to desert landscapes, wildlife travel far and wide to seek the best habitat for their survival. As urban and residential areas expand, wildlife increasingly finds their way into our backyards and neighborhoods. Although urbanization and other human activities degrade wildlife habitat worldwide, people can positively impact wildlife where they live. In particular, gardening for wildlife in residential yards and neighborhoods can provide crucial habitat for birds, bees, and other animals, thereby helping to protect wildlife and conserve biodiversity. 

Based at Arizona State University in Tempe, my research team has been collaborating with other researchers and conservationists to answer a variety of questions related to the environmental impacts of residents’ yards, broadly defined as the outdoor areas of homes inclusive of lawns (i.e., turfgrass), other plant species, gravel or wood mulch, patio areas, pools, and other natural or built features. Yards are particularly prevalent in neighborhoods with “single-family” or detached homes, in contrast to “multi-family” homes such as apartments and condos. You might ask: just how widespread are yards, and do they really matter? The short answer is yes — and in the U.S., residential areas cover about 30% of land, and among the U.S. housing stock, about two-thirds constitute single-family housing with yards, which we also refer to as residential landscapes or gardens. Since the design and management of these residential landscapes can significantly impact the environment, my research broadly examines: how and why do residents design and manage their yards in various ways, and what are the environmental as well as societal implications? 

As a Professor of Geography and Sustainability at Arizona State University (ASU), I have been conducting social science research on residential landscapes for nearly twenty years, particularly within metropolitan Phoenix and other urban regions of the U.S. My early research on yards primarily focused on water conservation in our arid region, since lawns and other landscape features (e.g., pools) in residential areas consume a significant amount of water. In fact, did you know that, collectively, residents’ irrigation of lawns and other plants — coupled with other outdoor water uses (including evaporation from pools) — constitute up to two-thirds of all water consumed in municipal (urban areas) of Arizona? Did you know that in Arizona's urban areas, up to two-thirds of all municipal water is consumed through outdoor uses, including lawn irrigation, plant watering, and pool evaporation? However, since the 1980s, cities like Phoenix and others in the southwestern U.S. have been transitioning away from mesic (wet) lawns to what researchers call xeric (dry) yards.

Xeric yards — which contain gravel or rock groundcover (instead of turfgrass, or lawns) — are often planted with native vegetation or climate-adapted, low water-use plants. As these landscapes have grown and replaced lawns in recent decades, the region has substantially lowered per-capita water use. This shift in residential (and other) landscapes not only conserves our state’s water resources; they can also have a positive impact on wildlife. So, over the last decade, I have been collaborating with ecologists and other social scientists to investigate: who is gardening for wildlife, and why? In other words, what factors motivate people to design and manage their yards in ways that provide habitat for wildlife, and what barriers exist to the adoption and expansion of wildlife-friendly yards? Meanwhile, I collaborate with ecologists and other scientists to examine how different yard designs and management practices affect the environment, including wildlife. 

From left to right: Diadasia diminuta, Lucifer sheartail hummingbird (Calothorax lucifer), and lesser longnosed bat (Leptonycteris curasuae yerbabuenae). Photos Courtesy of Bruce Taubert.

In a series of blog posts, my team will be sharing research on residential yards with you. The research projects we feature involve partnerships between ASU, the Arizona Wildlife Federation (AWF), and the National Wildlife Federation (NWF), especially their programs focused on gardening for wildlife. If you are unfamiliar with these programs, they include certification programs that acknowledge residents' efforts to provide food, water, and shelter to wildlife, which you can read more about on the AWF and NWF websites. In a previous project funded by the National Science Foundation, an interdisciplinary team of social and ecological scientists collected data in NWF-certified habitats in residential yards and other types of landscapes to measure plant and bird biodiversity. During this project, I also led the analysis of social survey data to better understand who is gardening for wildlife and what is motivating them relative to people with traditional lawns or other types of landscapes. More recently, we have been analyzing where Certified Wildlife Habitats® are located in the state, and how many yards and other types of properties have been certified over the last 50 years. In this blog series, we present the results and welcome your feedback. 

The ASU team includes three bright undergraduate students — all of whom are majoring in sustainability with links to geographical sciences and urban planning. All three are passionate about wildlife and conservation: Alexandra (Lexi) Cegielski, Sharika Kapur, and Sophia Ruger. Each student has co-written a blog post to share past and recent research findings.

First, Lexi details the biodiversity impacts of Certified Wildlife Habitats® in people’s yards compared to other types of yards and parks based on research by my colleagues, Drs. Padu Cubinos, who is a biogeographer, and Susannah Lerman, who is an ecologist.

Next, Sharika explains how aesthetics and maintenance concerns dominate when residents are making decisions about their yards. By extension, we provide tips for designing beautiful yards that are easy to maintain.

Lastly, Sophia Ruger presents our preliminary geospatial and temporal analyses of the Certified Wildlife Habitats® in Arizona, partly using Geographic Information Systems which enable mapping and spatial analysis. In addition to showing that the vast majority of certifications are in people’s yards, some years have experienced relatively high and low numbers of Certified Wildlife Habitats®, which are prevalent in some Arizona communities more than others.

We hope you enjoy learning about our work!