Climate Change, Environmental Justice, and Urban Greenspace

Note: this article was originally written for the Hardy Plant Society of Oregon (HPSO) Quarterly Magazine (spring 2022 issue). The wonderful team at the HPSO, especially Eloise Morgan, provided copy editing assistance on this article.


To observe Oregon State University’s annual Martin Luther King Jr. Celebration, the Master Gardener Program hosted a screening of the movie ‘The Ants and the Grasshopper’. The movie follows Anita Chitaya, as she travels from her home in Malawi, to farms and gardens across the United States to share her story of how climate change is impacting her village. Afterwards, Dr. Vivek Shandas of Portland State University joined us to discuss the intersection of historical racism, landscaping and greenspace, and environmental justice.

When Anita Chitaya was asked what Americans can do to help the people in Malawi, she responded that she wanted people to talk about climate change and tell people about the plight of her village. Her response struck me for three reasons. First, she could have asked for many different things, such as money or advocacy. Instead, she thought it most important to talk about climate change. She, like many of you, saw great value in spreading knowledge. Second, after considering Anita Chitaya’s request, I realized that I don’t personally talk about climate change, outside of my classes. The scientific study of climate change has firmly established that human-caused climate change is happening, is accelerating at an unprecedented rate, and represents a danger to the life as we know it on earth (IPCC, 2021). I firmly believe that climate change is the one of the most important issues of our time, and I regularly worry about the world that my grandchildren will inherit. Yet I still feel shy to broach the subject with friends and family. Finally, Anita Chitaya was working to amplify the voice and concerns of those most affected by climate change. And, the movie made it quite clear that those most affected by climate change often hold the least power. This is something that Dr. Jeremy Hoffman of The Science Museum of Virginia and Dr. Vivek Shandas of Portland State University have studied in cities across the United States. And their work has direct connections to landscaping and gardening, as well as to historical racism and segregationist policies.

Together with Nicholas Pendleton, Drs. Hoffman and Shandas looked at 108 cities across the United States (Hoffman et al. 2020). For each city, they looked at historical Home Owner’s Loan Corporation (HOLC) maps from the 1930s, to see which neighborhoods had been ‘redlined’. Redlining is the historical practice of refusing loans or insurance to entire neighborhoods, based upon racially motivated perceptions about risk of investment. HOLC maps categorized neighborhoods from “Best” (A neighborhoods, outlined in green), “Still Desirable” (B neighborhoods, outlined in blue), “Definitely Declining” (C neighborhoods, outlined in yellow), and “Hazardous” (D neighborhoods, outlined in red).

After defining the historical boundaries of the A, B, C, and D HOLC neighborhoods, the scientists generated Land Surface Temperature maps (LST maps) using publically available Landsat imagery. The LST maps were based upon Landsat data for summer months (June – August) of 2014 through 2017, when cloud cover was less than 10 percent. The resolution of the LST maps was fairly course (30 meters by 30 meters), but nonetheless provided data on neighborhood- and city-scale patterns of modern-day heat.

A HOLC  map for Portland Oregon, circa 1938. Green areas were rated ‘A’ or ‘Best’. Blue areas were rated ‘B’ or ‘Still Desirable’. Yellow areas were rated ‘C’ or ‘Definitely Declining’. Red areas were rated ‘D’ or ‘Hazardous’. Creative Commons License. Original Source: Robert K. Nelson, LaDale Winling, Richard Marciano, Nathan Connolly, et al., “Mapping Inequality,” American Panorama
, ed. Robert K. Nelson and Edward L. Ayers, accessed February 7, 2022, https://dsl.richmond.edu/panorama/redlining/

What they found was astonishing: 94% of the cities they examined had city-scale patterns of extreme heat in historically redlined areas. Let me put this another way: 80 years had passed between the HOLC maps and the LST maps that they used as data for this study and 50 years had passed since the Fair Housing Act of 1968 was passed to stop the practice of redlining. Yet, these neighborhoods still bore the signature of historical racism, in the form of urban heat. Notably, the largest modern-day difference between “D” and “A” neighborhoods was found in Portland, Oregon. On average, neighborhoods that had been classified as “D” in the 1930s were 13 degrees Fahrenheit warmer than neighborhoods that had been classified as “A”. Nationally, historical “D” neighborhoods were 5 degrees Fahrenheit warmer than “A” neighborhoods.

What could account for these differences in temperature? First, historical “D” neighborhoods lacked tree canopy cover, parks, gardens and other greenspaces and green infrastructure that can help to naturally cool a city. This is consistent with the historical disinvestment in redlined neighborhoods. Not only were loans and insurance withheld, but when trees were removed due to damage and disease, they were often not replanted. In addition, redlined neighborhoods were also the most likely to be developed. Residents in these neighborhoods often lacked the social capitol needed to successfully protest the loss of a public garden or park, or to fight a new road or highway. This meant that these areas, over time, were more likely to be paved, and less likely to have trees.

I asked Dr. Shandas, during our discussion following the film, how gardeners and landscapers can promote social justice and fight environmental racism through our work. He responded that urban greening and tree planting initiatives seem and obvious answer, but that they need to be planned and executed in close consultation with community members most affected by urban heat. Perhaps not surprisingly, these community members are often the most vulnerable to extreme weather and climate change, including the homeless or those in rental or federally subsidized housing and without easy access to air conditioning. For a good example of an effort to work closely with local communities to increase trees and greenspace in historically redlined neighborhoods, you can visit Dr. Hoffman’s ‘Throwing Shade in RVA’ website (Hoffman, n.d.).

Urban forests, such as the trees that provide beauty and shade on the Corvallis campus of Oregon State University, are important assets for moderating urban heat and integral to building and maintaining sustainable cities. Photo Credit: Gail Langellotto

I don’t purport to have great solutions or answers to heavy issues such as climate change, environmental justice, or historical and systemic racism. But, I take inspiration from the direction provided by Anita Chitaya, and I am working to become more comfortable talking about climate change. I’m also taking inspiration from the direction given by Dr. Shandas, and am trying to grow my service to community partners in a way that focuses on listening, learning, and following their direction. I also think that it is interesting to note how gardens, trees, and greenspace play a central role in who is exposed to versus protected from urban, extreme heat. As gardeners, these aren’t often issues that we consider or contend with. But, the Master Gardener program is focused on the science of gardens and other greenspaces, and Drs. Hoffman and Shandas have provided compelling evidence of the research-basis of patterns that we might not notice or that we take for granted in cities and neighborhoods across the U.S.


Hoffman, J.S. No Date. Throwing shade in RVA. http://jeremyscotthoffman.com/throwing-shade, Accessed February 1, 2022.

Hoffman, J.S.; Shandas, V.; Pendleton, N. 2020. The Effects of Historical Housing Policies on Resident Exposure to Intra-Urban Heat: A Study of 108 US Urban Areas. Climate 8, 12. https://doi.org/10.3390/cli8010012

IPPC 2021. Climate Change 2021: The Physical Science Basis. https://www.ipcc.ch/report/sixth-assessment-report-working-group-i/

Meet OSU’s Newest Extension Master Gardener Faculty and Staff

Laurie Lee Bartlett

Laurie Lee Bartlett is the new Educational Assistant at the Curry Extension Office. She is looking forward to taking the Coos/Curry Hybrid Master Gardener class for 2022! As an educator and previous caretaker to her now grown son, she is starting the next chapter of her life with a desire to serve others. This includes reaching out to everyone who wants to learn more about home horticulture. Her family enjoys practicing sustainable gardening on their acre of land and taking care of goats and chickens. This winter she has been expanding her collection of air plants and orchids which she houses in her sunroom and office. Laurie is grateful for the opportunity to be part of the OSU community!

Amanda Woodlee

Amanda Woodlee is the Master Gardener program coordinator (EPA 2) for Umatilla County, based in Hermiston, Oregon. This position enables her to combine two of her longtime passions: gardening and education. Prior to coming to work for OSU, she enjoyed putting together an annual seed share and gardening expo for her local garden club, where she would talk to attendees about pollinators and compost and all things green. She is excited to apply that same passion and skill to developing, organizing, and enhancing Master Gardener events. When she’s not in her greenhouse or bringing up worms randomly in a conversation, she can usually be found with her nose in a seed catalog or a book, writing (with her garden and two bird feeders in sight from her desk), or studying languages (currently Spanish, French, and ASL). Her favorite thing to grow is the Pruden’s Purple heirloom tomato, and the best book she read recently is Alix E. Harrow’s The Once and Future Witches.

Evie Smith

Evie Smith is the new Master Gardeners (25%) and Small Farm (75%) Coordinator for OSU
Extension in Lincoln County. She is coming to OSU Extension from the University of California Cooperative Extension, where she worked in orchard crop research. In the past, she has worked in several different agricultural systems including mixed vegetable production, aquaponics and coffee. She has several years of experience working in a large mixed vegetable garden that donated everything it produced to the local food bank. She was involved in both volunteer coordination and agricultural management at the garden. She also worked on home gardening initiatives and small-scale agriculture projects in a variety of agricultural contexts in the southeastern United States (where she’s from originally), Guatemala, Cambodia, India and California. An avid gardener herself, Evie looks forward to learning about gardening in Oregon, and to using her experiences with volunteer coordination, gardening initiatives, and extension to support the work of the Master Gardeners in Lincoln County! In her spare time, Evie loves to hike, camp, and cook.

Jennifer Halter

Jenifer Halter has worked as a front desk Office Specialist for Washington County Extension since May 2016.  She was excited to join the metro area Master Gardener team as part of her duties in October 2021.  She always assisted MGs in the office, especially those working the phone helpline, an aspect of the job she loved.  Jenifer is thrilled to work more with this great group and our exceptional volunteers.  She tries to attend MG workshops and visit garden events when she’s able.  After going to a Fall seed saving workshop at Jenkins Estate (Beaverton, OR) she aimed to grow more of her own garden plants from saved seeds.  In 2021, almost all of her tomatoes were grown from previous year’s seeds!  She recalled, “That workshop was so memorable and useful!”  It was led by Washington County MG, Sarah Gramm Wolff, a volunteer at the OSU Extension Learning Garden at Jenkins Estate.  Jenifer’s forester father instilled in her a love of nature, and she enjoys hiking, berry picking (especially huckleberries), doing yard work, biking local trails, and catching sunrises and sunsets.   She looks forward to learning and helping MGs more in 2022!

Erika Szonntag

Erika Szonntag serves Jackson County in southwestern Oregon.  Forty percent of her time is dedicated to managing the Master Gardener Volunteer Program, while another forty percent is dedicated to developing programming and otherwise disseminating information to the community on topics of home horticulture.  Erika is really looking forward to supporting all the great work the Jackson County Master Gardeners are doing, including expanding their educational reach around native plants. 

Before coming to Oregon, Erika was a professional gardener in Colorado while finishing her master’s degree in agriculture and watershed science.  Erika also served as a Peace Corps Volunteer in Paraguay (2014-2016) in agriculture extension.  In her free time, Erika loves to hike and trail run with her dogs, mountain bike, paint and draw, and play in the snow.  Her favorite things to grow in the garden are any type of salad green and sunflowers.  She wishes she were better at growing root vegetables!  

Brooke Edmunds

Brooke Edmunds recently transferred to oversee the Master Gardener Programs in Marion and Polk Counties in July 2021. She has been with OSU Extension since 2014 and previously was in the same position in Linn and Benton Counties. Brooke is an Associate Professor (Practice) of Community Horticulture with a home in the OSU Department of Horticulture. Her background is in plant pathology (M.S. and Ph.D) so you’ll find her nerding out over cool diseases and insects in the garden. In addition to coordinating the Master Gardener volunteer programs in both counties, Brooke contributes to statewide programs related to food gardening (Grow This! Champions and Microgreens are two current projects), and develops online educational material for the OSU Extension website. It’s an exciting time for the OSU Master Gardener Program and Brooke is excited to try out a new flexible format that includes hands-on garden based learning. Brooke’s personal gardening goals for this year are to try growing winged beans (Psophocarpus tetragonolobus) and to install a new trellis planted with Passiflora.

Danielle Knueppel

Danielle is located at the Josephine County Extension Office in Grants Pass and divides her time equally between the Master Gardener Program and the Small Farms Program. Danielle’s experience in horticulture includes farming at an organic fresh-cut herbs farm in Colorado, maintaining gardens alongside volunteers at the Cheyenne Botanical Garden, and working as a grower at greenhouses and nurseries in Colorado and Indiana, where she grew up. Before joining OSU, she worked internationally for several years on programs to improve livelihoods and food security among smallholder farmers. Danielle loves to garden and is excited to show new gardeners how fun, easy, and tasty it can be to grow your own vegetables, herbs, and fruits.