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Five Scientific Studies that Changed the Way I Think About Gardens: Part 2, Putting a Price on Nature

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This is the second is a series of articles that I am writing for the Hardy Plant Society of Oregon Quarterly Magazine. I extend my thanks to the HPSO editorial team for improvements to my narrative.

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Humans benefit from the natural world in many ways. These benefits include the products (such as food, fiber, or timber) that we can harvest from nature, or the processes (such as pollination, biological control, or nutrient cycling) that make earth such a nice place to live. Whether people recognize the importance of these so-called “ecosystem services” to our health and well-being varies considerably as a function of education, past experiences with nature, and other socio-economic factors. In fact, some people find abundant ecosystem disservices in nature. For example, some people view natural areas as dangerous places that should be avoided.

A major focus of the Garden Ecology Lab research program is to discover which garden plants may help maximize the ecosystem services of pollination and biocontrol.

In an increasingly urbanized world, where many people lack meaningful interaction with the natural world, how can we help ensure that the importance of nature is recognized and valued? As Robert Michael Pyle wrote in his book The Thunder Tree: Lessons from an Urban Wildland (1998: Oregon State University Press), “What is the extinction of a condor to a child who has never seen a wren?”

One approach to helping society value the natural world is to put a dollar value on it, and that’s just what Robert Costanza and 12 colleagues did over the course of a five-day workshop hosted by the National Center for Ecological Analysis and Synthesis in 1996. A few months later, they published the second global accounting of the monetary value of the ecosystem goods and services of our planet1.

The authors found over 100 studies that valued one or more ecosystem services. They standardized the dollar value of each ecosystem service as the 1995 dollar value per hectare. They noted the location of each study and categorized the biome where the study occurred. They also generated novel estimates of the dollar value of various ecosystem services in various biomes by constructing what were essentially supply and demand curves. With these curves, they mathematically asked questions such as “How much more valuable would pollinators be, if they were endangered?” In this way, they were able to mathematically manipulate supply and demand curves and estimate what is known as the “marginal value” of each ecosystem service. In short, they used a lot of math. On a global map, they measured the area taken up by each biome. They multiplied the dollar value of each ecosystem service per unit area by the area taken up by each biome and developed a global map of sum-total value of ecosystem services.

The authors estimated that the value of the earth’s ecosystem services averaged $33 trillion dollars per year (1995 dollar value), which was 1.8 times the global gross national product. Nutrient cycling represented the highest valued ecosystem service, at $17 trillion per year. Coastal systems were identified as the most valuable biome, at $12 trillion per year.

Urban and suburban areas were included in the study. What struck me about this paper, however, was that the dollar value of ecosystem services of urban areas was not listed. Instead, the authors noted that ecosystem services in urban areas (like desert, rocks, tundra) “do not occur or are known to be negligible.”

When I read this paper as a young Ph.D. student in 1997, I was incensed. My family grew food and raised chickens and rabbits in the backyard of our Baltimore rowhouse (ecosystem service = food). As a child, I captured water striders, turtles, and tadpoles from urban streams (ecosystem service = habitat). As an undergraduate, I loved exploring the urban forests of Patapsco Valley State Park for exercise and stress management (ecosystem service = recreation). Did urban areas really deserve a zero? This paper made me want to study the ecosystem services of cities, just to prove the authors wrong!

Composting is an example of the ecosystem service of waste treatment.

In 2002 I started to study the ecology of urban areas, as an assistant professor of biology at Fordham University in New York City. I collaborated with doctoral student Kevin Matteson to study the value of urban gardens as wildlife habitat and pollinator conservatories. We found that 18 small gardens dotting one of the most urbanized landscapes on earth were used by a diversity of insects, including 24 species of butterfly and 54 species of bee. At this same time, others were also documenting the ecosystem services of urban areas. For example, The New School’s Timon McPhearson estimated that raised bed gardens in New York City annually helped to retain and manage 12 million gallons of stormwater from flooding city streets. Karin Burghardt, as a University of Delaware undergraduate studying with Doug Tallamy, showed how plant choices can increase bird abundance and diversity in suburban gardens in Pennsylvania.

Raised beds in urban areas retain rainwater and reduce run-off and storm system overflows. This is an example of the ecosystem service of disturbance regulation.

In fact, the early 2000s were a heyday for urban ecology research, due in large part to National Science Foundation funding of urban long-term ecological research efforts in Phoenix, Arizona, and Baltimore, Maryland. Whereas less than one-half of one percent of all papers published in nine leading ecological journals between 1995 and 2000 focused on urban systems or urban species (Collins et al. 2000), by 2016 over 1,000 articles, books, and book chapters have been published; and over 130 students have been trained in urban ecology by the Phoenix and Baltimore programs, alone (McPhearson et al. 2016). Despite these advances, the field of urban ecology is still relatively young, and much remains to be discovered.

In 2014, Costanza and colleagues published a new paper, with an updated estimate for the value of our globe’s ecosystem services.2 They estimated that natural systems annually provided $125 trillion (2011 US$ value) in ecosystem services to humanity. At least part of this increase is due to improved documentation of the portfolio of ecosystem services provided by different biomes (see table). And this time, ecosystem services provided by urban areas were valued at $2.3 trillion dollars, or $2.9 trillion in inflation-adjusted dollars for 2020.

”Hmph,” I thought. “At least it’s a start.”

1Robert Costanza et al. (1997): “The value of the world’s ecosystem services and natural capital.” Nature 387: 253-260.

2Costanza (2014): “Changes in the global value of ecosystem services.” Global Environmental Change 26: 152-158.

Table 1. The Value And Ecosystem Services Provided By Various Biomes On Earth. All dollar values have been inflation adjusted to 2020 dollar values, and are reported as TRILLIONS of dollars. Red Text: Identified as a service in Costanza et al., 1997, but not 2014; Green Text: Identified as a service in Costanza et al., 2014, but not 1997; Black Text: identified as a service across both papers.

BiomeValue from 1997 PaperValue from 2014 PaperEcosystem Services
Open Ocean$14.8$27.9Gas regulation, Cultural, Climate regulation, Genetic resources, Recreation, Nutrient cycling, Biocontrol, Food
Coastal$22.1$35.3Climate regulation, Erosion control, Genetic resources, Disturbance regulation, Nutrient cycling, Biocontrol, Waste treatment, Habitat, Food, Raw materials, Recreation, Cultural
Forest$8.3$20.7Gas regulation, Pollination, Habitat, Climate regulation, Disturbance regulation, Water regulation, Water supply, Erosion control, Soil formation, Nutrient cycling, Waste treatment, Biocontrol, Food, Raw materials, Genetic resources, Recreation, Cultural
Grassland$1.5$23.5Climate regulation, Water supply, Habitat, Raw materials, Genetic resources, Cultural, Gas regulation, Water regulation, Erosion control, Soil formation, Waste treatment, Pollination, Biocontrol, Food, Recreation
Wetlands$8.5$33.65Gas regulation, Climate regulation, Erosion control, Nutrient cycling, Biocontrol, Genetic resources, Disturbance regulation, Water regulation, Waste treatment, Habitat, Food, Raw materials, Recreation, Cultural
Lakes/Rivers$2.9$3.1Water regulation, Water supply, Waste treatment, Food, Recreation
Desert$0$0 
Tundra$0$0 
Ice/Rock$0$0 
Cropland$0.3$11.9Climate regulation, Water supply, Erosion control, Soil formation, Waste treatment, Raw materials, Genetic resources, Recreation, Pollination, Biocontrol, Food,
Urban$0$2.9Climate regulation, Water regulation, Recreation

Five Scientific Studies that Changed the Way I Think About Gardens: Part 1

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[Preface: For the past few years, I have written a column for the Hardy Plant Society of Oregon’s (HPSO) Quarterly Magazine. It has been a wonderful experience, as the HPSO provides excellent editorial assistance. Below, I share my most recent article for the HPSO Quarterly, and thank Eloise Morgan and her team for helping to improve and elevate my writing.]

I spend my nights thinking about gardens: not about the plants that I want to purchase or the crops that I want to plant. Instead, I puzzle over how to study a system that is incredibly variable (from person to person, or even in the same person’s garden from year to year) and complex (with more plant species than just about any other system that has been studied). Gardens are both wild and managed, and unlike other systems I have worked, it is impossible to divorce human behavior from the ecology and evolution of the garden.

In this series, I wanted to share five scientific studies that have had a large role in shaping how I think about gardens. Because of space limitations, I will share the first study in this article. I will wrap up the remaining four studies, in subsequent issues. The five studies are:

Simberloff and Wilson (1969). This study commenced 54 years ago, and yet remains a ‘must read’ for any ecology student. In 1966, Dan Simberloff and Ed Wilson selected six small mangrove islands off the coast of Florida. The islands varied in distance from the mainland coast, from near to far (Figure 1a), as well as size, from small to large (Figure 1b)

Figure 1. In Simberloff and Wilson’s experiment, they selected mangrove islands that varied in their (a) distance from the mainland (the coastline of Florida) and (b) their size. Attribution: Hdelucalowell15 / CC BY-SA (https://creativecommons.org/licenses/by-sa/4.0)

Simberloff and Wilson constructed a scaffold that encircled the edge of each island, covered the scaffold with a tarp, and then proceeded to ‘defaunate’ each island with methyl bromide pesticide. In other words, they killed every arthropod on the islands. After removing their ‘death tents’, and over the course of the next year, they carefully monitored, cataloged, and counted every arthropod that arrived and survived on each island. What they discovered was formulated into the ‘Theory of Island Biogeography’, or a theory about how organisms colonize new habitat, and assemble into a biological community.

They found that islands that were closer to the mainland coast of Florida were colonized earlier, and accumulated species faster, compared to islands that were farther (Figure 2). They also found that species would accumulate on each island, over time, until a maximum peak is reached (not shown). Then, the number of species would begin to drop, as ecological interactions (such as competition for food) would allow some species to prosper, while others went locally extinct. They found that smaller islands were more prone to species extinctions, than larger islands (Figure 2).

Figure 2. Island size (small or large) and distance from the mainland coast (near or far) infuenced the dynamics of species colonization and extinctions on mangrove islands. Image Source: https://commons.wikimedia.org/wiki/File:Island-biogeography.jpg#file

Size, distance, age: those are the three things that Simberloff and Wilson predicted would govern the diversity and assembly of organisms within a habitat.

My first faculty position was at Fordham University in New York City, where I studied pollinators in 18 community gardens in Harlem and in the Bronx. During the course of this study, I was inspired by Simberloff and Wilson. I could not help but see the 600+ community gardens that dot the landscape of New York City as islands of green in a sea of concrete.

We expected that gardens that had been long-established would have more pollinator species than newer gardens. We expected that larger gardens would host more pollinator species than smaller gardens. And, we expected that gardens that were closer to ‘mainland’ sources of pollinators, such as Central Park or the New York Botanical Garden, would have more species of pollinator than those that were distant.

We were wrong on two out of three predictions (Matteson and Langellotto 2010). Larger gardens had more pollinator species than smaller gardens, but neither distance nor age had any impact. I was so disappointed that we did not find an effect of distance, or of garden age. I had visions of ‘revitalizing’ the Theory of Island Biogegraphy for urban landscapes, but it was not to be. If anything, our study suggested that the ‘sea of concrete’ was not exactly a wasteland, afterall. The street trees, potted plants, windowsill gardens, and patio gardens all provided resources for urban pollinators, even in one of the most densely populated and heavily developed cities in the world.

This study showed me that it will be much more difficult to track pollinator movements among urban gardens, than I had hoped. We tried to use a traditional mark-recpture approach (see Matteson and Langellotto 2012), but out of 476 marked butterflies we only found four in a garden other than which it was marked and released. We were searching for the ‘needle’ of small butterflies in the ‘haystack’ of the New York City landscape. My students tried to follow pollinators as they left our study gardens, and almost got hit by a car, as they were running across the street. We played around with the molecular markers of a few bumblebees (see Morath 2007), to see if there was evidence of genetic differentiation, but were stymied by a lack of reliable primers that could help us look for any genetic differences in bees from different gardens. And then I moved to the Willamette Valley, where gardens are islands of green in an ocean of green. Understanding what draws pollinators to particular gardens will be even more difficult in this landscape, where pollinators have so many other choices for finding nectar and pollen.

Based upon our initial results from our Portland Garden study (2017-2019), I think I have a new hypothesis as to what might draw pollinators to home and community gardens. Our second study year (2018) was characterized by a hot and dry summer. Our first sampling season was also dry, but the spring months were wet, and the summer was cooler. In 2018, we collected far more bees (abundance) and more types of bees (species) than we collected in 2017 or 2019. In 2018, the landscape of the Willamette Valley was toast! Almost all flowering plant materials seems to shut down photosynthesis, so that they could conserve pressure water that would otherwise escape through open stomates. In this type of situation, bees seemed to concentrate in home gardens, which seemed to be one of the few places where they could reliably find nectar and pollen.

If this is the case, gardens aren’t necessarily going to be an important source of floral resources across all years. In a good year, there should be other plants in bloom in the greater landscape that bees can use. But in a hot, dry year, gardens may become an even more important refuge for bees. Most gardeners provide irrigation, which extends the bloom season beyond what is natural in the valley. Or, gardeners select plants that can prosper and bloom without supplemental irrigation, such as goldenrod or Douglas aster. It’s important to note that, even in the hot, dry weather of 2018, we still collected more bees from gardens that used drip irrigation, rather than overhead sprinklers. I think that the overhead irrigation physically blocks bees from navigating through a garden, which lessens their abundance and diversity.

Ultimately, I hope that our studies can lead us to a more predictive model of the resource value of home gardens to pollinators. The goal isn’t necessarily to understand what gardeners should do to attract pollinators, but to describe the conditions where gardens become increasingly important to pollinator conservation. In addition, I’d love to describe the value of gardens, relative to other habitat types, to pollinators. And finally, I hope to better understand the direction and movement of pollinators between gardens and other habitat types.

 

Garden Ecology Lab Research Update

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COVID-19 has impacted our research in many different ways, including making it more difficult to find time to provide research updates on a regular basis. Despite the long silence, we have many projects up and running this summer! In fact, we’re launching four new projects, finishing up three long-term projects, and writing up another two projects.

In this blog post, I give a brief overview of the four new Garden Ecology Lab projects that launched this summer.

Microbiome of Garden Soils and Gardeners: Dr. Gwynne Mhuireach’s project has been spotlighted in a recent blog post and webinar. She has selected the 40 gardeners that will be included in her study: 20 high desert and 20 Willamette Valley gardeners, half of whom are organic and half of whom are conventional gardeners. Soon, these gardeners will be sending in their soil and skin swab samples. And then, the long process of analysis will begin.

She’s studying the microbe community in garden soils, and how those might differ according to garden region (Willamette Valley or high desert) and gardening practices (organic versus conventional soil managmeent). She’s also studying whether garden soil microbes transfer to gardeners’ skin during the act of gardening, and if so, how long those microbes persist on the skin.

Pollinators on Native Plants and Native Cultivars: Jen Hayes is well into the data collection phase of her first field season. She is working with undrgraduates Jay Stiller, Tyler Spofford, and Isabella Messer to: track flowering phenology, measure floral traits, observe pollinator visits to study plots, and collect pollinators so that they can later be curated and identified to species. Jen has written about her research project, in a past blog post. I’ve also set up a Flickr album to host photos from her study.

Native plant and nativar study site, at the Oak Creek Center for Urban Horticulture. A yarrow cultivar, ‘Salmon Beauty’, can be seen in the foreground. Nemophila, Clarkia, and Escholzia cultivars can be seen in the background.

Jen’s field site is located at the Oak Creek Center for Urban Horticulture at OSU, which makes it so much easier for undergraduate student researchers to participate in this project. She samples pollinators on Tuesdays and Fridays. She takes 5-minute observations of pollinator visits on Mondays and Thursdays. In between, lots of time is spent weeding and watering plots, counting flowers, and measuring floral traits.

Cost / Benefit Analysis of Growing Edible Plants in Containers: Tyler Spofford is a new lab member, who is completing his undergraduate degree in the BioResource Research program at OSU. He is working to develop a ‘budget’ for growing food in low-cost containers. I’ve summarized this ‘budget’ data for growing food in standard vegetable gardens, but no data yet exists (that I can find) for containerized vegetable gardens. Tyler is growing 40 tomato plants across two sizes of containers (3 gallons and 5 gallons), as single plants and in combination with basil. He’s keeping track of all of the costs (both money and time spent to grow food). When he harvests food, he’ll weigh his harvest, and track the economic benefit of his efforts, and how container size and planting configuration (one or two crops per container) influences harvest. I’ve set up a Flickr album for his study, to host project photos.

Tyler’s project grew out of my concern that, even though 18,000+ people enrolled in a free, online vegetable gardening course (over 40,000, at last count) ~ that the people who might be most at risk for food insecurity may not be benefitting from Extension Master Gardener resources and information. Tyler’s project is one component of a larger effort to develop more support for renters who might want to grow their own food.

Bucket gardens, on the day that the tomatoes were planted into 5-gallon BiMart buckets. We tried to keep all materials and plants low cost and easily accessible. Photo Credit: Tyler Spofford.

Below is an excerpt from a concept paper I’m writing on the topic:

We know that the COVID-19 pandemic is exerting stress on multiple pressure points related to the economic and food security of U.S. households: more people are in need of food aid and more people are concerned about food access. The U.S. has a long history of gardening in times of national emergency (e.g. Victory Garden of WW I and WWI II, ‘recession gardens’ of 2008). The benefits of gardening as a tool of economic security and resilience are well-established. However, research suggests that these benefits are largely restricted to homeowners. Currently, most state and local laws afford no legal right to renters who want to grow their own food. Community gardens might offer renters opportunities to grow their own food, except that these gardens are often associated with gentrification. To promote public health in the face of economic and health risks of COVID-19 and future pandemics, it is critical to support the food gardening efforts of the most vulnerable. Those in rental housing have been found to be most vulnerable to food insecurity, as well as the food and economic insecurity associated with natural disasters.

Pollinators on Buddleja Cultivars: Cara Still is studying how breeding butterfly bush (Buddleja davidii cultivars) for sterilty impacts the pollinator community that visits Buddleja blossoms. Buddleja davidii and some fertile varieties of this plant are considered noxious weeds in Oregon, and many other places. Normally, noxious weed status would make it illegal to sell or trade butterfly bush in Oregon. However, the Oregon Department of Agriculture allows exceptions for non-sterile cultivars and interspecific hybrids.

Buddleja ‘Buzz Velvet’ (I suspect that plant breeders have a lot of fun, naming new cultivars)

Cara is studying whether or not the plants that are allowed for sale, under the exceptions, still pose a risk of invasion. Our group is working with Cara to document the abundance and diversity of pollinators that visit eight fertile Buddleja cultivars with 16 cultivars that have been bred for sterility.

When I was initially approached to participate in this project, I thought that it should be obvious that sterile cultivars would not attract pollinators. Afterall, sterile cultivars don’t produce pollen, or produce very little pollen. Without pollen, I doubted that bees would visit the plants. But, it is possible that sterile plants would still produce nectar. And, many pollinators ~ such as butterflies and moths ~ visit plants to consume nectar, rather than pollen.

The more I looked into the literature, I realized that no one has yet studied how breeding for sterility might affect a plant’s attractiveness to pollinators. Would sterile forms of butterfly bush no longer attract butterflies? Would sterile varieties attract syrphid flies that visit blossoms for nectar, and not pollen? We’ll let you know what we find, in about a two years. In the meantime, you may want to visit the Flickr album of photos I set up for Cara’s study.

Link to ‘Garden(er) Microbiome’ Webinar Recording

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Thanks to all who signed up for the ‘Citizen Science in the Garden!: Studying the Garden(er) Microbiome’ webinar. The webinar recording can be found below, or via THIS LINK.

If you are interested in participating in this project, please leave your information in this short survey. We will work to get back to everyone who responds, within the next month. Depending upon the volume of interest that we receive, it may take a bit longer.

Thanks to all wanting to learn more about the microbiome of garden soils and gardeners!

Welcome Gwynne Mhuireach and the Garden(er) Microbiome Project

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This post a from Gwynne Mhuireach, who will be studying the microbiome of garden soils . . . and gardeners!!

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A little about me…

Gwynne Mhuireach will be studying the microbiome of garden soils and gardeners!

I am a researcher, farmer, and mom to twin teenagers. My formal education is broadly cross-disciplinary, including degrees in biology, architecture, and landscape architecture. While I was working on my Masters, I began studying microbes inside buildings as a member of the Biology and Built Environment Center at the University of Oregon, where we discovered that our exposure to microorganisms indoors depends a great deal on what microorganisms are present in the immediate outdoors. This line of inquiry was so fascinating that I entered the PhD program in Landscape Architecture to investigate how urban green space might influence the airborne microbial communities that people are exposed to in their daily lives. Ultimately with my research, I aim to gain a deeper understanding of how human health and environmental health are connected through the microbes we share. 

In addition to my academic research, I also own and operate a small livestock farm with my two teenagers, Lyric and Cadence, and my partner, Tom. A native Oregonian, I was born and raised on a small farm near Klamath Falls, Oregon, where my family produced (and continues to produce) hay and cattle. Now I choose to continue the agricultural lifestyle that has been my family’s way of life for three generations. Producing food through hard work and stewarding a small piece of land to pass on to my children is very important to me. I believe that having a strong connection to the land is also part of what drives me to study microbes in the context of the outdoors, particularly how we interact intimately with them by getting our hands dirty in the soil.

The Garden(er) Microbiome Project

In partnership with Gail Langellotto, I am launching a new citizen science project called, “Microbes under your fingernails? An exploration of the garden microbiome and potential transferability to human skin.” While soil science is well-developed in terms of nutrients and organic matter needed to keep plants healthy, less is known about the diversity and composition of microbes present in agricultural soils, particularly in small-scale farms and gardens. Astonishingly, despite the likelihood of substantial exposure to soil microbes while gardening, yet we lack even the most basic understanding of how much microbial transfer from soil to skin occurs, what types of microorganisms are transferred, or how long they persist. Through this project, we seek to answer these questions with the help of volunteers—you!

Gardeners who volunteer to participate in this project will be asked to collect soil samples from several different beds in their gardens and from the surface of their hands and/or forearms. There will also be questionnaires that ask for information about garden management practices and daily skin care (use of anti-bacterial soap or lotion, etc.) during the sampling period, which will last 2 days. Volunteers will receive detailed results, including a comprehensive soil health assessment and skin/soil microbiome reports. We will also share our findings with other researchers, farmers/gardeners, and the broader public online and through the Master Gardener network. We anticipate that this citizen science project will not only answer our original research questions, but also shed light on how different management practices can impact garden soil health in different climate zones of Oregon.

If you are interested in participating in this project, I am hosting an informational webinar on Friday, June 5th (2020) at 10am. Registration is required to attend. The webinar will be recorded and posted.

If you are unable to attend, but are still interested in participating, please let us know a bit more about you and your garden by taking this short survey. Please note that for this particular project, we are specifically seeking gardens located in Oregon’s Willamette Valley or High Desert regions.

How COVID-19 Has Impacted the OSU Garden Ecology Lab

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I asked our group if they would be willing to share how COVID-19 is impacting their science, their studies, and their life. Our collective reflections can be found, below.

Gail Langellotto, Professor and Statewide Master Gardener Coordinator: In early February, I woke up from a dream, sobbing. I had dreamt that my parents were sick in Baltimore, but that domestic air travel had been shut down. I am not an expert in the ecology of infectious disease, but I used to teach infectious disease models to pre-meds. And, there were several things that I saw in reports of this emerging disease that greatly troubled me. Unfortunately, my fears of large scale community spread have come true, and life has changed for us all. Luckily, my parents and sisters continue to be healthy, even though they live in a COVID-19 hotspot.

I teach two face-to-face entomology courses at OSU during the spring term: ENT 311 and ENT/HORT 444/544. I had exactly one week to pivot these classes to fully remote offerings. Instead of real time (and automated) assessment of learning using TopHat, I’m building quizzes and assignments into Canvas, where I am manually grading 210 quizzes and assignments per week. I’ve drastically cut down on course content, in part because I continue to try and focus on essential messaging, but also because I know that many of my students are under immense stress.

Spring term is when I normally move to having a lighter touch with the Master Gardener Program. New Master Gardener students are completing their coursework and exams. Long-time Master Gardeners move their attention to plant sales, garden fairs, and educational outreach. Not this year. Training classes had to move online or to Zoom. Plant sales, garden fairs, and other Master Gardener events were cancelled. Our working group started trading resources and ideas via weekly Zoom meetings. Each new dictate from the Governor or the University requires attention and consideration of how it applies to the Master Gardener Program. It’s been a challenge to stay on top of everything, and a challenge to keep a positive attitude.

In terms of science, there has been good and bad. The ‘bad’ is that, as an Associate Editor of the journal Urban Ecosystems, it has been difficult to find peer reviewers for scientific manuscripts. And, it feels ‘out of touch’ to prod folks to get their reviews in, when they may be sick, or they may be busy home-schooling kids or shopping for senior family members. Also in the ‘bad’, I generally have zero time or energy to work on my own scientific manuscripts. Exhaustion is a constant. The ‘good’ is that I can’t sleep at night. And, during these sleepless nights, I often think about next steps in our research, and plotting out key questions in urban ecology that remain unresolved, but could be addressed in garden systems.

Gail’s workstation at home. The photo of the bear and fish (to the right) is named ‘A meditation on perspective’. When working, I often stop to tell myself ‘be the bear, not the fish’.

Angelee Calder, senior year June 2020, Agricultural Science undergraduate: Covid has greatly impacted my plans and life!  As some of you may remember from my last blog post, I was expecting to spend my final term as a senior at Oregon State University doing an internship in Costa Rica! Twelve days before I was scheduled to leave, we entered a worldwide pandemic and all my plans where flipped and turned upside down! In preparation to leave for Costa Rica, I had put in my 30 day notice in on my apartment and my roommate found somewhere else to live. Last minute, I had to scramble to get my refunds, register for classes, and find somewhere to live. Since then, I have been struggling with homelessness.

Currently, I am living in the emergency housing at OSU provided by the Human Resources and Services Center. While I am extremely thankful to be here, I am only permitted to stay for less than a month. Which means my struggle with homelessness during my final term of school will continue to be an issue well into finals week. I started my first term at OSU homeless and I am finishing my final term homeless! While this is stressful and uncertain, I have managed to continue to kill this term academically. I am proud of myself for prevailing during these hard times to thrive under these heavy pressures and keep my eyes on the prize of my diploma that I have worked 5 long years to earn.

My passion for agriculture and my dedication to school go unwavered. This time has helped me to feel more secure in my chosen field as Agriculture than I ever have before. After seeing the bare shelves at the store and hundreds of thousands of Americans get laid off of their jobs, I realize agriculture is about as “essential” as you can get! My passions and education can not only create stable work for myself but also can help the rest of the world through these difficult times with stable sustainable food production.

Angelee’s workstation at the OSU Human Services Resource Center.

Mericos Rhodes, M.A. Student in Environmental Arts and Humanities. As a practitioner of ecological agriculture, this COVID era is one of the most interesting times of my life. Put simply, I have never witnessed such intense interest in what is, to me, the most interesting topic in the world: local ecological farming.

The farm that I help run, Spoon Full Farm, has completely sold out of CSA memberships and many other items. Our waitlist is growing. Here in Corvallis, the farmers markets are well-adjusted and well-attended. I can understand why: a shorter food chain means far fewer opportunities for food to be contaminated. Healthy nutrient-dense food is a cornerstone of resilient health. Small businesses such as local farms need our support now, more than ever.

In an exciting development, a friend and I are busy converting an old grassy field, across from the Corvallis Fairgrounds, into a small-scale community-based farm. We connected with the landowner after he put up a sign at the co-op seeking farmers! So, our restorative farming project has begun! It doesn’t look like much, but we have 7 chickens moving rapidly through the grass between our dug rows of mixed perennials (mostly currant bushes and thyme), fertilizing the ground to support annual vegetable beds. We plan to dig a little pond and use a heavy mulch of leaves and/or wood chips.

The Corvallis field that Mericos and his partner are converting into a farm.

How is this relevant to the garden ecology lab? In two ways:
First, I am planning my graduate project to be a narrative introduction to ecological farming (stories, characters, motives will be highlighted). This personal experience will be part of the story. Second, this project will put into place many practices suggested by Gail’s Insect Agroecology class (ENT 544), which I am currently taking, including creating diverse perennial habitat for insects, and not spraying pesticides or synthetic nitrogen. It will also be an experiment in “Dry-Farming,” which basically means zero irrigation – perhaps a critical farming technique here in the Northwest, where irrigation water may be in much shorter supply, in the decades to come.

I feel extremely grateful to be able to work outside, with living nature, during these times when so many are stuck in screen world, all day every day.

Aaron Anderson, PhD Candidate: During this uncertain time, I feel lucky to be able to be part of the Garden Ecology Lab and be able to continue my classes and work. As I am in my fourth year as a graduate student here at OSU, I have already collected all of my field data. This means that I am able to hunker down at my desk here at home, without having to worry about the logistics of conducting fieldwork during a pandemic. I’ve been busy taking two courses, and also plugging away on some data entry and statistical work.

Things can be undeniably stressful due to the background worries about COVID-19, but working from home has had some plus sides. The first is the ability to work with a cuddly cat on my lap. I’ve also been able to take breaks out in the yard, where we’ve been working on our garden bed and also seeded the side yard with several native plants from my study. We have Phacelia heterophyla just starting to germinate, and Clarkia amoena and Achillea millefolium are both beginning to bolt. Hopefully, some native bees will be visiting soon!

Aaron’s cat.
Aaron’s side garden.

Signe Danler, Instructor, online Master Gardener training course: As an instructor of an online course, most of my work was already done online via computer before the pandemic hit. I have also worked from home for many years in a variety of jobs, so I already had a full office set up at home, and did much of my OSU work at home already. In this regard, there was not much change – I grabbed a few things from my office at OSU so I would have them at home, and have not been on the campus since the stay-at-home order.

Nevertheless, life suddenly became much more stressful. For the first few weeks, the constant bombardment of new and conflicting information was terribly distracting, making it hard to be productive on any project requiring sustained effort. The cancellation of virtually all events I normally participate in has been saddening and frustrating. With two vulnerable family members at home, we have to exercise great caution in outside contacts. I not only have to do all grocery shopping, but do it in a way that takes much longer than usual, and is tiring and stressful. I’m keeping trips out very infrequent!

All in all, though, I feel we are very fortunate, since we are in a position to ride this situation out with minimal problems. To stay healthy and sane I’ve been taking more walks, which is easy since we live at the edge of town and crowds are non-existent. My large garden is getting more attention than usual, and I’m propagating more of my own plants to reduce nursery visits. As I have adjusted to the new normal, my ability to focus is getting back to normal too, and I am confident we’ll get through it just fine. 

Signe’s Plant starts.

Mykl Nelson, Instructor of Urban Agriculture: The first thing I noticed was how much remained the same. I was already fully remote and integrated with eCampus. I was lucky. I watched the flurry of emails, the hectic conference meetings, the string of popular articles. Everyone seemed to scramble as essentially the entire academic world pushed to move fully online and remote. I’m excited to see this push because I hope to see advancement in the teaching of remote teachers. When I first started trying to educate myself about educating others in agricultural topics in a remote classroom, I saw very little supporting material. I hope that changes now.

I’ve seen real changes in the community around me. Store shelves lay bare as a slow realization—the façade of abundance—spreads across stores. I know from my time as a grocery clerk that those shelves aren’t stocked that deep, and the “back stock” is kept as thin as possible. I’m watching my country get squeezed around me; the most vulnerable of my fellow citizens being forced to confront the more dire aspects of this pandemic. 

But in this panic, I feel safe. I get to add yet another scenario to the privileged category of my life. From my youth in a military family to my time now as university faculty, I am repeatedly shown the benefits of access to health care. When it comes to basic hygiene and global health, I want everyone to be able to wash their hands just as easily as they could access medicine. It only makes sense to extend such secure foundations to as many people as possible.

Mykl’s workstation in Central Oregon.

Happy 50th Anniversary of Earth Day

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Today is the 50th anniversary of earth day. I am almost as old as earth day (I will turn 50, next February), and am finding myself in a reflective mood.

Ever since I was a child, I have been fascinated by and loved nature. I used to try and catch lightning bugs, and put them in a mason jar, hoping to catch so many that I could make a lantern. Today, when I visit my folks near my childhood home, nary a lightning bug can be found. Scientists suspect that increased landscape development has removed the open field habitats and forests that the lightning bugs depend upon to display their mating signals and to live. Light pollution likely also plays a role.

lightning bug 8758
Eastern Lightning Bug. Photo Credit: Terry Priest. https://www.flickr.com/photos/artfarmer/197649535

My time in college was my first real exposure to nature. I worked at Patuxent Wildlife Research Center, supporting the work of James Wagner when he was a graduate student at UMBC. He was studying wolf spiders, and I fell in love with these amazing creatures. Did you know that wolf spider mommas carry their young on their back ~ at least for the first few days of a baby spider’s life? Did you know that to collect wolf spiders, you go out at night with a flashlight . . . shining the flashlight into the forest floor litter, to find eight tiny glowing eyes staring back at you? Wolf spider eyes glow, as an adaptation to capture more light (enabling them to see better) when hunting at night. Like a cat’s eye, wolf spiders have a tapetum at the back of their eye . . . a mirror that re-reflects light back out, and lets the spider’s eyes have a second shot at capturing that light. My time working with James was magical. For the first time in my life, I gained the skills to identify trees, and wildflowers, and birds, and insects. I tell people that it was as if a scrim had been lifted from my eyes, and I saw the world in an entirely different light. I was forever changed, by this newfound knowledge that allowed me to ‘read’ the natural world in a different way.

Behind the rusty eyes
A wolf spider. Photo Credit: Jean and Fred. https://www.flickr.com/photos/jean_hort/4430861610

As a graduate student, I studied salt marsh insects on the New Jersey coastline. I had never been to a salt marsh before, despite living within an hour of the ribbon of salt marsh that hugs the eastern seaboard. I saw horseshoe crabs for the very first time. I saw the fishing spiders in the genus Dolomedes that I had read about in books. I went bird watching and butterfly hunting with scientists who were generous with their time and knowledge, most notably, my advisor, Robert Denno. Now, so much of that ribbon of coastline has been destroyed. What remains is at risk due to increased nutrient pollution from fertlizers and run-off.

Big cordgrass salt marsh
Tall grass in an eastern salt marsh. Photo Credit: Ecological Society of America. https://www.flickr.com/photos/ecologicalsocietyofamerica/25086412492

My post-doctoral work was spent in California on many projects, including studying the food webs of cotton fields that were using organic or conventional production practices. From talking to the farmers and stakeholders, I learned that there are not insurmountable impediments to growing organic cotton. The problem was that there was a limited market for organic cotton, grown in the United States. Growers who would plant organic cotton faced an uncertain market and reduced yields. Often, reduced yields might be compensated for with a premium price for organic products. But not in the case of US-grown organic cotton. This is when I first started to realize that science can not work in a silo, but that an understanding of economics and the social sciences is critical to promoting more sustainable solutions.

My first faculty position was at Fordham University in the Bronx. I had no idea what I would study, as an entomologist in the Bronx. Luckily, I had the great fortune of taking on Kevin Matteson as my first graduate student. Kevin had been studying the birds of New York City community gardens. I asked him if he might be willing to instead study insects. His work was ground-breaking and is heavily cited, showing the potential of small garden fragments in one of the most heavily populated cities in the world, to support a diverse and abundant assemblage of insects. He also showed that the strongest predictor of butterfly and bee diversity in gardens was floral cover. Through Kevin’s work, as well as associated work by Evelyn Fetridge, Peter Werrell, and others in our Fordham lab group, I became convinced that the decisions that we make in home and community gardens have the potential to make a real and positive difference in this world.

I came to OSU in 2007, for the opportunity to work with about 30 faculty and staff and between 3,000-4,000 volunteers who were dedicated to sustainable gardening. Coming from a teaching and research position to an Extension position was initially a challenge for me. I recognized importance of bringing good science to Extension and outreach work, but I didn’t know exactly how I would or could contribute. In 2016, I started the Garden Ecology Lab at OSU, mostly because I was more convinced than ever, that having good science to guide garden design and management decisions can truly make a positive difference in this world. I sometimes talk about ‘how gardening will save the world’, which is a lofty and aspirational goal. But, I truly believe (and science backs up this belief), that the decisions that we make on the small parcels of land that we might have access to in a community or home garden matter. These design and management decisions can either improve our environment (by provisioning habitat for pollinators and other wildlife) or harm our environment (by contributing to nutrient runoff in our waterways, or by wasting water when irrigation systems fall on the sidewalk more than on our plants).

This is one reason that I stand in awe of the Master Gardener Program. When I was purely a researcher, rarely interacting with the public, I doubt that many people were able to take our research findings and apply them in their own yard. When I was initially struggling with my new Extension position, I went to my former Department Head at the University of Maryland entomology deparment, Mike Raupp. Mike had a lot of experience with Extension and outreach, in addition to being a world-reknown researcher and a super-nice person. I remember him saying ‘Gail, when you publish a research paper, you’re lucky if 20 eggheads will read it. When you talk to the Master Gardeners, you have the opportunity to make real change in this world.’

And together with the Master Gardeners, I hope that is what we have done. I hope that is what we will continue to do. I hope that we find new and novel ways to discover how folks can manage pests without pesticides, to reduce water use in the home garden, and to build pollinator- and bird-friendly habitat. And then I hope that we will reach and teach our neigbhors and friends how to appreciate the biodiversity in their own back yard, and the small changes that they can make to improve the garden environment that they tend. I hope that we can instill a wonder for the natural world in the next generations, and to preserve or improve the natural world, so that our kids, and grandkids, and subsequent generations can hunt for lightning bugs, or spiders, or butterflies.

And I want to do it with you, dear gardeners. Together, we truly can make a difference.

Does Repeated, Lethal Sampling Contribute to Insect Declines?

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Over the past few months, I have shared data on bees and other insects that we have collected from Portland-area gardens. For every garden insect we study (except for butterflies, which can be identified to species by sight), we use lethal collection methods. This is because most insects can only be identified to species after close examination under the microscope. In fact, some insects require dissection before we can get them to species.

Bombus sitkensis male, with abdomen dissected, in order to make a species-level identification.

It seems odd that we kill bees in order to help understand how we can build gardens that can help to conserve bees. By collecting and killing bees and other insects, what role were we playing in promoting insect decline? How do projects, such as our own as well as the Oregon Bee Atlas, factor into bee declines?

That’s an excellent question, and one that we often ask ourselves. When we collect bees, we work to make sure that we are not needlessly causing harm. For example, our pan traps are good for collecting small bees, but are not good at collecting larger bees, including reproductive queens. When we hand-collect bees, we avoid taking queen bees. In fact, of the 2,716 bees that we collected in 2017-2019, only three were queens. We limited our sampling frequency to three times per year, and limited our sampling effort to 10 minutes of hand-collecting time and six pan traps, per garden. Even with these precautions, we are still faced with the question: does our research, or the research of others who collect and kill insects, harm the very species we are trying to conserve?

Water pan traps, used to collect garden bees and other small, flying insects. Insects are attracted to the color. When they land in the soapy water, they break the surface tension, drown, and die.

To address this question, I turn to the scientific literature. Gezon and colleagues set up an experiment to see whether lethal sampling for bees using pan traps and netting (the same methods we use in our research) has negative effects on bee abundance or bee diversity. For five years, they sampled nine sites every two weeks during the flowering season. They compared bee abundance and bee diversity in these repeatedly-sampled sites, to metrics from 17 comparable sites that were only sampled once. They found no significant difference in bee capture rate, bee species richness, or bee abundance between sites that were sampled repeatedly versus those that were sampled once. When they partitioned bees according to nesting habit (e.g. cavity, soil, wood, etc.), social structure (e.g. eusocial or not), and body size (e.g. small, medium, and large bees) they also found no significant differences in bee capture rates of single-sample versus repeat-sampled sites. They did catch more pollen specialists in repeated-sample sites than in single sample sites. However, the magnitude of the effect was relatively small, and did not represent a large change in catch rate between single-sample versus repeat-sampled sites. I suspect that the authors caught more pollen specialists at their repeat-sampled sites, because pollen specialists are fairly rare in time and in space. They drastically increased their odds of intercepting a pollen specialist on their repeatedly-sampled sites.

Gezon and colleagues suggest a few hypotheses that could explain why increased sampling effort had no significant effect on bee abundance or diversity. First, they suggest that reducing bee populations by sampling could benefit the bees that remain, by reducing competition for limited resources. If this is the case, bee populations can compensate for some losses due to sampling, by increasing reproduction in the bees that remain behind. Second, they note that if bees were sampled after they have mated and laid eggs, the overall impact of removing a bee from via sampling will be fairly small. Finally, they note that most bees are solitary, and that most solitary bees have short flight seasons. In this case, sampling every two weeks may not result in bee declines, if researchers are effectively collecting a new species during each sampling event.

I can breathe a bit easier. The data suggests that our research is not immediately responsible for documented bee declines. Still, I know that I can personally do more to help protect bees in my own garden. Even though our lab group studies native plants, I have not yet planted Aster subspicatus (Douglas’ Aster) in my own garden. This will be my mission for 2020: to find and plant this gorgeous perennial at home. In 2018 and 2019, it bloomed from mid June through mid November at our study plots in Aurora, OR, with peak bloom (75% or more of the plant in bloom) lasting one month! And, from 2017-2019, it was always a top five plant for native bee abundance. I give this Pacific Northwest native plant my highest recommendation for home gardens! There are plants that attract more native bees, such as Phacelia heterophylla. But, no other plant that we studied offers the triple threat of beauty, bees, and longevity.

Douglas’ aster (Aster subspicatus) is currently my favorite garden plant for bees.

A Primer on Parasitoids

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You know about butterflies, about bees, beetles, and ladybugs, all of our favorite garden critters – but do you know about the parasitic wasp? Alias: The Parasitoid. Not quite a parasite and not quite a predator, they are the zombie-creating hymenopterans that make your garden their home and hunting ground. Unlike a true parasite, the parasitoid will eventually kill its host, but unlike a true predator, there is a gap between parasitism and host death. The Parasitoid is truly one of a kind, but with thousands of species in over 40 families, there are many of that kind. They prey by laying their eggs in or on the bodies and eggs of other arthropods, growing, aging, and getting stronger as their unknowing host provides their executioner food and shelter until the parasitoid is ready to attack. 

A Trissolcus japonicus parasitoid wasp lays eggs inside brown marmorated stink bug eggs at the USDA-APHIS Quarantine Facility in Corvallis, Oregon. Photo courtesy of Christopher Hedstrom
Parasitoid laying eggs in stink bug eggs. Photo Courtesy of Christopher Hedstrom

 As menacing as their way of life may seem, parasitic wasps are actually one of the most effective biological pest control agents available to home gardeners, and can be an excellent indicator of habitat health for ecologists. As biocontrol agents, parasitoids can effectively manage a very wide variety of pests from aphids and sawflies to weevils and mites, along with many more. They occur naturally if their hosts/prey and habitable conditions are present and it costs little to nothing to maintain their populations. If pest outbreaks are not completely out of control and the site is habitable, parasitoids can safely, easily, cost-effectively, and naturally bring pest populations below economic injury thresholds. Know any pesticides that check all those boxes? In terms of habitat health, parasitoids can drive biodiversity and positively influence ecosystem functions. As such, their diversity and abundance can act as an indicator for the overall health and functionality of an ecosystem – such as your home garden. 

Is it starting to seem like parasitic wasps could be an area of research for say. . .a garden

A Parasitoid collected from a Portland Garden in 2017 during the Garden Pollinator study

ecology lab? Certainly seems like that to me. That’s why this upcoming year I will be taking on an undergraduate research project to assess the parasitoid populations present in the Portland home gardens Gail and I have collected bees from for the last 3 years. Thanks to our sampling methods, we already have lots of parasitoid data to perform this analysis with, so there won’t be any more soapy bowls in your gardens this summer. This is the first of hopefully many blog posts that will accompany this research, so stay tuned as the year progresses to learn more about your new flying friends!

Further Reading and References: 

https://www.cell.com/trends/ecology-evolution/comments/S0169-5347(06)00152-2

http://publications.gc.ca/collections/collection_2015/aac-aafc/A59-23-2015-eng.pdf

http://ipm.ucanr.edu/PMG/PESTNOTES/pn74140.html

Video showing some parasitoid activity:

Setting up a native plant and native cultivar study

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Natives Plants & Native Cultivars Recent studies report an increase in consumer demand for native plants, largely due to their benefits to bees and other pollinators. This interest has provided the nursery industry with an interesting labelling opportunity. If you walk into a large garden center, you find many plant pots labelled as “native” or “pollinator friendly”. Some of these plants include cultivated varieties of wild native plant species, or native cultivars, sometimes referred to as “nativars”. While many studies confirm the value of native plants to pollinators, we do not yet understand if native cultivars provide the same resources to their visitors.

Echinacea purpurea

Photo Source: Moxfyre – Own work, CC BY-SA 3.0,

E. purpurea ‘Maxima’

Photo Source: Ulf Eliasson – Own work, CC BY 2.5,

E. purpurea ‘Secret Passion’

Photo source: National Guarden Bureau

An Echinacea Example Above are three purple cone flower (Echinacea purpurea) plants: on the top is the wild type, in the middle is a native cultivar ‘Maxima’, and on the bottom is another native cultivar ‘Secret Passion’. In some cases, like ‘Secret Passion’s double flower, there is an obvious difference between a native cultivar and a wild type that might make it less attractive to insect visitors. Since we can’t see the disc flowers (the tiny flowers in the center of daisy family plants), we might assume that ‘Secret Passion’ may be more difficult for pollinators to visit. The floral traits displayed by ‘Maxima’ seem similar to the wild type, but it might produce less pollen or nectar, causing bees to pass over it.

Unless we observe pollinator visitation and measure floral traits and nectar, we can’t assume that native plants and native cultivars are equal in their value to pollinators.

Native Cultivar Research One study looking at the difference between native species and their cultivar counterparts has come out of the University of Vermont (my alma mater!). A citizen science effort started by the Chicago Botanic Garden is also currently ongoing. My Master’s thesis will be the first to use a sample of plants specific to the Pacific Northwest. We have selected 8 plants that are native to Oregon’s Willamette Valley and had 1-2 native cultivars available. These plants have shown a range of attractiveness to pollinators (low, medium, or high) based on Aaron’s research. We are including plants with low attractiveness because it’s possible that a native cultivar may have a characteristic that makes it more attractive, such as a larger flower or higher nectar content.

This example of a Randomized Complete Block design shows 2 garden beds containing a native species (California Poppy and Camas) and their cultivar pairs (a yellow poppy cultivar and a white Camas cultivar).

Experimental Design We have four garden beds in our study, and each bed contains at least one planting of each native species and their cultivar counterpart(s). This kind of design is called a “Randomized Complete Block” (RCB). The RCB has two main components: “blocks”, which in our case are garden beds, and “treatments”, which are our different plant species. Above I have drawn a simplified RCB using two of our plants: Camas and California poppy. The bamboo stakes outline each plot and have attached metal tags that label the plants.

We planted our seeds and bulbs in November and will plant out 4″ starts of the other plants in early Spring. Look out for my spring and summer updates to see how these plots progress from mulch and bamboo stakes to four garden beds full of flowers and buzzing insects!

Reference articles: https://www.asla.org/NewsReleaseDetails.aspx?id=53135 http://www.gardenmediagroup.com/garden-media-releases-2019-garden-trends-report