Behind the Scenes of the Portland Bee Guide!

Posted on October 24, 2023 by Nicole Bell

What is the Portland Bee Guide?

This month has seen the release of the Portland Bee Guide! This guide was a collaborative project among many different members of the Garden Ecology Lab, along with numerous others inside and outside Oregon State University. Our goal for the project was relatively simple: create an accessible guide to Portland bees. If you haven’t already, click here to download the Portland Bee Guide. It contains species descriptions of 67 bee species found in Portland, OR, gardens (including the ones seen below!), and the accompanying iNaturalist guide (click here) contains photos and interactive functional trait filters for each species. Read on for bonus content, not included in the bee guide or in the social media campaign we ran to promote the guide earlier in recent weeks.

This blog will also serve as an access point to the social media content, for those not on Instagram or Facebook. The social media campaign contained three sets of posts: one focused on floral resources for bees, another on nesting sites for bees, and the final was a feature of some of the Portland bee-friendly gardeners.

Making the Guide

Most of my time spent on the guide happened in my home, which is my preferred work space (it helps that a cat is included). Specifically, a table on the same back patio where I grew up spending time with my family in the outdoors as I was growing up. When I entered graduate school, the sampling in Portland gardens was already finished—so many people had contributed to this project before I ever knew it existed. The main thing that inspired me to work in science communication was the opportunity to serve as a liaison between the academic sphere and the public sphere. I’ve always enjoyed interacting with people, and was parented by scientists who valued their work in Extension programs.

The back patio, where I spent much of my time this past summer working on the bee guide.

Because so much of my work took place on my computer, far removed from the soil, forage, and buzzing bees of Portland, I knew I wanted to make visiting some of the gardens a priority. This would allow me to have a deeper understanding of the guide itself prior to its release, as well as to take photographs and interview some of the gardeners who hosted diverse bee communities in their backyard. I completed my visits in June 2023, and got a chance to talk with gardeners about their successes, setbacks, motivations, and more. Let’s look at some of these gardens!

Our 3 Featured Gardeners

Pascal: “Small and mighty”

Pascal’s garden is in Northeast Portland. He lives just off a busy street, so his main goal when creating his garden was privacy. I was inspired by Pascal’s eye for design—his garden, to me, was the definition of maximizing space. He has created a layered effect, with winding pathways, designated sections for food crops and ornamental plantings, but everything blended seamlessly. Though I could tell from the road that Pascal’s garden was going to be quite something, while I was inside it felt like I was in on a secret: here I was, in a secluded refuge.

I asked Pascal!

What is the biggest challenge you deal with in your garden? “My biggest challenge is keeping the garden healthy and thriving during dry stretches of weather, which seem to be getting longer each year. I use soaker hoses throughout the garden and run them once a week, but during extreme heat and dry weather over the last few summers, the stress on the plants is obvious. I’m now running them more often, and this year, earlier than in previous years. More water means a bigger water bill, but it’s better than losing established plants to drought. When I do lose plants, I now plant replacements that are native and more drought tolerant.”

What has been your biggest gardening success? “My biggest gardening success has been transitioning this yard, that was basically lawn and a few trees, into a biodiversity hotspot with almost 80 species of plants stuffed into a small space. All those plants now provide a lush green wall that blocks out some of the noise and business of our urban location. They also provide shelter and forage year-round for a variety of birds, insects (including pollinators), a few small mammals and even a lost cat, who we were able to rehome.”

What is your favorite spot in the garden? “My favorite spot in the garden is under the canopy created by a series of overlapping trees that create a cool, shaded area over the lawn. It’s the perfect spot to sit on a hot day and face out towards the surrounding gardens and see all the activity that is going on with birds, bees, and other insects moving around. The yard is still noisy, but sitting under those trees feels peaceful.”

Pascal and my father, Neil (also a retired Community Horticulturist for Oregon State), talking about plants in Pascal’s urban refuge. I love this photo because you can get a feel for the layered effect that this garden has. The variety of foliage textures makes the space feel welcoming, cozy, and vibrant.

Bob: “A bee’s urban paradise”

I visited Bob, along with a fellow Master Gardener, Cathy, at the Multnomah County Master Gardeners Demonstration Garden. This garden is open to the public, and Bob made is clear that visitors are welcome. Visitors are free to come walk around the garden, which is not limited to pollinator-oriented spaces. Other gardeners focus on food crops, ornamental plantings—there’s even a willow tunnel to walk under. The garden is beautiful, and worth a stroll-through if you’re in the area. It was such a joy to talk with both of them—their passion for both pollinators and gardening was tangible, and his interest in learning more about the bees he was seeing in his plot was inspiring.

Bob and Cathy standing next to their sign at the Multnomah County Demonstration Garden. If you’re in the Portland area, take a visit! It’s open to the public, and they were both wonderful to talk to.

The number of active pollinators here was astounding! Many of my now-favorite bee photos came from my visit to Bob’s garden. Male long-horned and leaf-cutter bees snoozing inside California poppy, Agapostemon (“green bees”) on Gaillardia, and bumble bees abounded during my midday visit. Many of those bees are pictured in our social media campaign, which will be included below.

I asked Bob!

What is the biggest challenge you deal with in your garden? “Unwanted plants. However, we have developed management strategies to deal with them. We plant very densely and layer plants vertically; we also tolerate some ‘weeds’.”

What has been your biggest gardening success? “Over time, Master Gardener colleagues—some of whom initially looked askance at what we were doing—have come to appreciate the aesthetic of our plantings. While some still wouldn’t garden the way we do, they now recognize that there’s a method to our madness.”

Where is your favorite spot in the garden? “I enjoy standing at the intersection of the steppingstone pathways, where I feel engulfed by vegetation.”

Sherry: “A suburban oasis”

Sherry is a long-time supporter of the lab, and follower of our research. One of my favorite parts of her garden is her planting of Douglas aster and goldenrod, which she was inspired to plant based on Dr. Aaron Anderson’s research, a past GEL lab member. The plating overlooks the Willamette River. I included this quote in the social media campaign, but I can’t help from including it here too: “Growing together, both receive more pollinator visits than they would if they were growing alone. It’s a testable hypothesis; it’s a question of science, a question of art, and a question of beauty.” – Robin Wall Kimmerer, from Braiding Sweetgrass.

Something I admire about Sherry’s garden is how she incorporates both native plants, and also plants that are important or special to her. It reminds me of my childhood garden growing up, planted and cared for by my parents, both horticulturists. I remember being surrounded by vegetation on our back patio, which was one of the first places I ever experienced the natural world up close.

I asked Sherry!

What is the biggest challenge you deal with in your garden? “Leaving unwanted and unmulched ground for nesting bees is hard for me. Bare ground goes against my nature!”

Sherry has done a wonderful job of incorporating more patches of bare soil into her garden: these spots are perfect for ground-nesting bees!

What has been your biggest gardening success? “A bee garden starring Douglas aster and goldenrod, two natives that tested well in the Garden Ecology Lab research. I added Allium, Emerus, rose, Persicaria, Phlox, Verbascum, and a Vitex for diversity and to extend bloom time.”

Where is your favorite spot in your garden? “I favor areas where there is a place to pause and reflect: an alcove off the driveway affords a scene of raised beds against a coral-colored wall, a bench surrounded by a circle of Phlomis offers expansive views of the pollinator garden, and a second-story deck gives a bird’s eye view of colorful shrubs and perennials below.”

Sherry standing next to the Phlomis in her June garden. This is one of her favorite spots to pause and admire the work she has put into this space. I can see why!

Social media content lives here, too!

Above: the set of slides included in our first post, which focused on floral resources for bees.

Above: the set of slides for our second post, which covered nesting sites for bees.

Above: the third and final post in our social media campaign, featuring Portland gardeners Pascal, Bob, and Sherry!

Thank you to everyone who has taken the time to tune in over the past month. Take some downtime during our rainy Oregon winter to familiarize yourself with the written guide PDF (downloadable here) and the online interactive iNaturalist guide (click here), so you’re ready for all our Portland bees next spring!

Do you have questions about the guide? I am more than happy to chat with you! Feel free to reach out to me at nicolecsbell@gmail.com.

Gardeners Needed for a Native Plant Survey!

Posted on October 9, 2023 by Jen Hayes

Study: Native Plants & Native Cultivars: Understanding Pollinator Preference for Native Plants and their Cultivated Counterparts in the Pacific Northwest

Thank you for your interest our survey! We are done collecting survey responses at this time. If you previously took the survey and have any questions, please direct them to Gail.Langellotto@oregonstate.edu and/or Jen.Hayes@oregonstate.edu.

The Controversy Surrounding ‘No Mow May’

Posted on September 20, 2023 by Gail Langellotto

This article was written for the regular column that I submit to the Hardy Plant Society of Oregon (HPSO) Quarterly Magazine. I am grateful to the team at HPSO for their editorial skills and feedback, that always improve what I write.

No Mow May is an initiative that was started in 2019 by Plantlife, a non-profit that works to restore meadow habitats in the United Kingdom. Their annual campaign called on garden owners and greenspace managers to cease mowing in the month of May, in order to move lawn-dominated yards towards a more natural approach. The movement quickly spread to other regions of the globe, as an easy and feel-good measure that almost any land manager could take to promote biodiversity and protect pollinators. In the United States, Bee City USA adopted the No Mow May campaign, which they also refer to as Mow Less Spring, as a way to conserve native pollinators.

A No Mow groundcover, being managed for increased flowers and pollinators. Photo by: Kenneth Allen (CC BY-SA 2.0). Source: https://www.geograph.ie/photo/6860492

There is some science to support the notion that less-intensely managed lawns benefits biodiversity. Our lab group even wrote about it in a blog post on No Mow May, including sharing a meta-analysis of 14 studies from North America and Europe showed that plant diversity and invertebrate diversity increased in lawns, as mowing intensity decreased [1]. However, several studies included in this review had mowing treatments that are not generally practical for most residential yards. Some studies compared lawns mowed once per week to lawns that were mowed once per year, for example. One of the few studies that compared mowing frequencies that approximate real world conditions was conducted in Springfield, Massachusetts [2]. In this study, Dr. Susannah Lermann and colleagues compared bee abundance and diversity from yards mowed every week, every two weeks, and every three weeks. Lawns mowed every three weeks had 2.5X more lawn flowers than other lawns. Interestingly, lawns mowed every two weeks had the highest bee abundance, but lowest bee species richness. The authors speculate that the higher grass height of the three-week mowed lawns covered lawn flowers, and made them less accessible to many bees. The higher lawn height also made the three-week mowed lawns less acceptable to nearby neighbors, leading the authors to suggest that a ‘two-week regime might reconcile homeowner ideas with pollinator habitat’.

Example of a lawn-dominated yard participating in the Lermann et al. 2018 study. Note the minimal landscaping and bare patches in the lawns, which were common throughout the sites. Also note the yard sign in the lawn explaining the objectives of the study. Photo Credit: Susannah Lermann, from Lermann et al. 2018.

That brings us back to No Mow May, and whether or not there is science to support the idea that not mowing for an entire month might benefit pollinators. In 2020 (soon after the start and spread of No Mow May) Del Toro and Ribbons published a paper that suggested that households that observed No Mow May had three times more bee species and five times higher bee abundance than spaces that were regularly mowed [3]. The results were highlighted in a New York Times story [4], and resulted in a change in the City of Appleton code that suspended an 8” lawn height restriction for the month of May, via a 6-3 split vote for and against the resolution [5]. Israel Del Toro, lead author of the study, was elected to Appleton’s Common Council, soon after leading the effort to adopt the resolution. By 2022, an additional 25 U.S. cities had followed suit [6], with their own declarations in support of No Mow May.

As the No Mow May movement grew, so did controversy surrounding the Del Toro and Ribbons study. Bee taxonomist Zach Portman noted serious issues with the bees identified in the study. Horticulture Professor Bert Cregg noted that the study was confounded, by comparing home lawns that were not mowed to park spaces that were mowed. With this experimental design, it is impossible for the authors to disentangle the effects of mowing (e.g. mowed or not mowed) from the effects of habitat type (e.g. home lawn versus park). In November of 2022, the authors retracted their study ‘after finding several potential inconsistencies in data handling and reporting’. After the retraction, the City of Appleton considered a resolution to eliminate No Mow May, claiming that the program lacks scientific backing. However, this resolution did not pass [7].

What is a science-informed gardener to do, amidst confusing and sometimes conflicting messaging related to pollinator conservation in a yard? First, note that science self-corrects, when the system works well. Retractions are part of that corrective process. Second, remember that bees can be found in lawn areas, particularly if lawns are less managed. The Lermann study demonstrated that lawns can host a surprising richness of bee species: 72, 60, and 62 bee species, in lawns mowed every week, two weeks, or three weeks, respectively. Note that to be part of this study, homeowners had to agree to not use herbicides or irrigation, during the length of the study. As a result of reduced management, lawns in this study often had bare patches that might be good nesting habitat for soil-nesting bees. Relaxing your mowing regime to every 1-2 weeks is supported by good science. Stowing your mower for an entire month is not. Finally, if you want to manage your yard for pollinators, planning and planting a pollinator garden is likely to net more species than stowing your mower. Indeed, many critics of the No Mow May movement, including native plant advocate Doug Tallamy, suggest that providing a temporary safe haven, regardless of its length of time, is counterproductive for pollinators and other wildlife it was meant to benefit. We currently have a paper in review, addressing this very topic. I look forward to sharing the highlights with readers, once it is published.

A Willamette Valley lawn with grasses setting seed, after weeks of no mowing. Photo Credit: Gail Langellotto.

[1] Journal of Applied Ecology 57: 436-446

[2] Biological Conservation 221: 160-174

[3] PeerJ 8:e10021

[4] New York Times, March 28, 2022.

[5] Appleton Common Council resolution and vote, April 1, 2020.

[6] NBC 26 Local News, April 22, 2022.

[7] Post Crescent, April 10, 2023.

Biodiverse Gardens Can Improve Bee Nutrition and Reduce Bee Disease

Posted on May 1, 2023 by Gail Langellotto

This article was originally written by Gail Langellotto for publication in the Hardy Plant Society of Oregon Quarterly Magazine, available to HPSO members.

You are what you eat. This phrase can be traced back to an 1826 essay by Anthelme Brillat-Savarin, who wrote ‘Tell me what you eat and I will tell you what you are.’ Diet and health are inextricably linked for almost all animals, including bees.

Bees foraging from flowering plants obtain carbohydrates from nectar. Pollen provides protein, fats, and vitamins. While the quantity of food is provided by the abundance of floral plantings, the quality of food is determined by the diversity of floral plantings. This is because different flowering plants offer different nutrients to bees’ diets. And, different bees have different nutritional requirements that vary among species, or that vary across life stages of a single species. For example, mason bee larvae (Osmia bicornis) larvae performed best on carbohydrate rich diets. Fluctuations in protein made little different to bee health, but carbohydrate deficiencies slowed mason bee larval growth and reduced survival[i]. Bumblebees (Bombus terrestris) foragers select foods that provide a target mix of 71% proteins, 6% carbohydrates, and 23% lipids[ii].

A graph with nutrient 1 on the x axis and nutrient 2 on the y axis. Five ellipses are drawn in two dimensional space, to illustrate the hypothetical nutritional niches of five bee species. — Hypothetical optimal (horizontal lines within each ellipse) and the tolerated nutritional niche (lighter color of each ellipse) of five bee species (Sp1, Sp2, etc.). Strong deviations from the optimal nutritional niche will likely lead to negative impacts on bee health, over time. From Parreño et al. 2022, https://www.sciencedirect.com/science/article/pii/S0169534721003335#f0010

Diverse floral plantings also help to reduce bee disease. Flowers have been shown to be hotspots for bee disease transmission. If you think of a flower as an elementary school drinking fountain, it makes sense that a sequence of bees could be exposed to disease carried by previous floral visitors. Following a visit by parasite-infected bumblebees, some flowering plants (such as milkweed or bee balm) harbored more bee pathogens than others (e.g. thyme or snapdragons) [iii]. And here’s a fun fact you have likely never come across before: bees preferentially poop on seaside daisy compared to a variety of other flowering plants in the Malvaceae, Verbenaceae, or composites with less floral area in disk flowers[iv]. Planting diverse flower types diffuses interactions between healthy and diseased bees. Not all floral morphologies effectively hold and transfer disease. And, planting diverse plant types provides more foraging options for bees, which can limit opportunities for healthy and diseased bees to come into contact.

While some flowers may be hotspots for bee disease transmission, others provide anti-microbial compounds that help some bee to naturally fight disease. The common eastern bumblebee (Bombus impatiens), but not the brown-belted bumblebee (Bombus griseocollis) was able to fend off parasite infection after consuming sunflower (Helianthus annuus) pollen[v].

Research on the nutritional ecology of wild bees is relatively young. And, from what we’ve learned thus far, different bee species have different nutirtional needs. It’s thus impossible to provide a specific garden plant recipe that can promote optimal bee health. Nonetheless, a few key points are clear. Monocultural cropping systems are harmful to bee nutrition. Just as you or I could not achieve optimal health by limiting our diet to one food item, neither can bees. And, this nutritional harm that monocultural cropping systems presents to bees doesn’t even consider the increased pesticide applications that single-cropped systems generally require. Gardens, on the other hand, are better poised to meet the nutritional requirements of bees, by virtue of the diverse flowering plant community that is typical of most gardens.

Thus, in case you need a reason to go out and discover new flowering plants for bees and other beneficial insects in your garden, bee nutrition is yet one more reason to build biodiverse plantings into your garden design.

An image of garden flowers, with lawn in the foreground. — Gardens with diverse and abundant flowers provide healthy nutritional landscapes for bees. Photo by Gail Langellotto

An image of a young woman, collecting bees from flowering plants in a container garden. — Container gardens can be used to provision diverse floral resources for bees, when space or soil is limited. Photo by Gail Langellotto

[i] Austin and Gilbert. 2021. Solitary bee larvae prioritize carbohydrate over protein in parentally provided pollen. Functional Ecology 35: 1069-1080. https://doi.org/10.1111/1365-2435.13746

[ii] Kraus et al. 2019. Bumblebees adjust protein and lipid collection rules to the presence of brood Current Zoology 65: 437-446. https://doi.org/10.1093/cz/zoz026

[iii] Adler et al. 2018. Disease where you dine: plant species and floral traits associated with pathogen transmission in bumble bees. Ecology 99: 2535-2545. https://doi.org/10.1002/ecy.2503

[iv] Bodden et al. 2019. Floral traits predict frequency of defecation on flowers by foraging bumble bees. Journal of Insect Science 19: 1-3. https://doi.org/10.1093/jisesa/iez091

[v] Malfi et al. 2023. Sunflower plantings reduce a common gut pathogen and increase queen production in common eastern bumblebee colonies. Proceedings of the Royal Society B 290: 20230055. https://doi.org/10.1098/rspb.2023.0055

Petal-cutting Bees!

Posted on January 27, 2023 by Mallory Mead

A study of leafcutter bees and a PNW native flower, through the lens of iNaturalist.

The Clarkia Project team: Mallory Mead, Jen Hayes, Sarah Erskine, and Ali Filipovic

If you are a subscriber to our blog, you have likely seen our photos and videos of one of our favorite plant-pollinator interactions: the petals of Farewell-to-Spring (Clarkia amoena) being harvested by leafcutter bees!

After observing this eccentric harvest behavior in the research garden, we got curious about the bees behind the petal-nest craft, and how we could study this interaction further.

Leafcutter bee mid-petal-harvest! Photo by Devon Johnson.

Crescent-shaped petal-cuts left behind by leafcutter bees.

iNaturalist is a popular community-supported biodiversity database that the Garden Ecology Lab has been experimenting with in recent years. Jen realized that the leafcutter bees’ distinct crescent-shaped mark are visible in many iNaturalist observations of Clarkia amoena. She wondered how we could use the already sizeable iNaturalist database of Clarkia amoena observations to study the interaction over a wider geographic and chronological scale than that of the research garden. Jen and Gail agreed to mentor me in producing an undergraduate research thesis on this subject.

The study’s objective is to use iNaturalist’s data on Clarkia amoena to see if there is a difference in leafcutter bee usage of Clarkia amoena petals based on whether the flower is a native versus a cultivar type, and whether the flower is found in an urban or non-urban environment.

In this process we have found that iNaturalist is easy for anyone to contribute to, but the information it provides is limited compared to the wealth of contextual information gained when being in the actual, living presence of a specimen. So, to get a greater feel for the intricacies of this flower, I embarked on what we called “Ground-Truthing Field Trips” to check out some Clarkia amoena populations in the “real world”.

I went out during peak pollinator season, following the coordinates of recently posted iNaturalist observations. Each specimen I visited was incredibly different from the next. I found the delicate blossoms in natural areas, the borders of farmland, restoration sites, and gardens.

Data from these trips will not be published in my thesis because the contexts are not exactly comparable, and my sampling was exploratory rather than precise. Nonetheless, I gained contextual insight and inspiration watching diverse pollinator assemblages in beautiful meadows of pink.

Mallory at a meadow restoration site near Corvallis with *Clarkia amoena* and tarweed (*Madia* elegans).

The field trips have helped us more clearly see through the window of iNaturalist and have informed the methodology we use.

For example, I saw examples of hybridization between two species of Clarkia in a seeded restoration site, and cultivar-hybrid escapees in natural areas. It’s been important to navigate identification of cultivars and hybrids in iNaturalist.

In a restoration prairie seeded with two different Clarkia species, pollinators cross-pollinate them, giving rise to sterile hybrids (Lewis & Raven, 1958). Note the malformed stigma and anthers.

Simultaneously, our field crew recorded petal-cutting behavior on the Clarkia amoena natives and nativars at Jen’s research garden this summer. Below are the three cultivars in the garden, and if you look closely you can see “petal-cuts” which we counted and recorded weekly. We will analyze the difference in leafcutter usage between the cultivars and native type.

This hot pink, stripy *Clarkia* doesn’t look like either the native or cultivars we had planted!

Clarkia amoena is an annual that reseeds itself effectively, so last year’s seeds gave rise to this season’s blooms. To our surprise, however, Clarkia amoena of all different colors started popping up in our research plots this Spring! Last season’s bees had combined pollen from the garden’s varieties bringing rise to all sorts of intermediate forms.

Clarkia amoena is prone to hybridization between members of the species or cultivars in the same proximity. These intraspecific hybrids are fertile. We seek to explore how cultivar genetics may be moving into natural populations.

Through the winter, our team is working with the iNaturalist data to quantify leafcutter bee petal usage. We expect to share our results in June 2023, so stick around to hear about our findings!

Work Cited:

Lewis, H., & Raven, P. H. (1958). Rapid Evolution in Clarkia. Society for the Study of Evolution, 12(3), 319–336.

2022 Field Update: Native plants & native cultivars

Posted on December 26, 2022 by Jen Hayes

This summer we completed our third and final field season surveying pollinator visitation to native plants and native cultivars! We will maintain our experimental garden for one additional season, to finish up some plant measurements and data collection missed in our initial three seasons. This post will serve as a 2022 field update in addition to summarizing some of our preliminary results from our field observations!

Study Plants (2020-2022)

*Discontinued in 2021 due to lack of vigor and availability of replacement plants
**Added in 2021 to replace removed plants
*******Discontinued after 2020 due to taxonomic inconsistencies

Scientific Name	Common Name	Plant Type
Achillea millefolium	Yarrow	Native
Achillea millefolium ‘Calistoga’*	Yarrow	Cultivar
Achillea millefolium ‘Salmon Beauty’	Yarrow	Cultivar
Achillea millefolium ‘Moonshine’**	Yarrow	Cultivar
Aquilegia formosa	Western Red Columbine	Native
Aquilegia x ‘XeraTones’		Cultivar (hybrid)
Camassia leichtlinii	Great Camas	Native
Camassia leichtlinii ‘Caerulea Blue Heaven’	Great Camas	Cultivar
Camassia leichtlinii ‘Sacajawea’	Great Camas	Cultivar
Symphyotrichum subspicatum	Douglas’ Aster	Native
S. subspicatum ‘Sauvie Sky’	Douglas’ Aster	Cultivar
S. subspicatum ‘Sauvie Snow’	Douglas’ Aster	Cultivar
Clarkia amoena	Farewell-to-spring	Native
Clarkia amoena ‘Aurora’	Farewell-to-spring	Cultivar
Clarkia amoena ‘Dwarf White’	Farewell-to-spring	Cultivar
Clarkia amoena ‘Scarlet’**	Farewell-to-spring	Cultivar
Eschscholzia californica	California Poppy	Native
E. californica ‘Mikado’	California Poppy	Cultivar
E. californica ‘White’	California Poppy	Cultivar
E. californica ‘Purple Gleam’**	California Poppy	Cultivar
Nemophila menziesii	Baby Blue Eyes	Native (California)
N. menziesii ‘Penny black’	Baby Black Eyes	Cultivar
N. menziesii ‘Snow White’	Baby Blue Eyes	Cultivar
Sidalcea asprella ssp. virgata*******	Rosy checkermallow	Native
Sidalcea malviflora ‘Purpetta’*******		Cultivar
Sidalcea malviflora ‘Party Girl’*******		Cultivar

We conducted 5-minute visual observations on our study plants over three seasons. During these observations, we recorded all insects that interacted with a plant. These interactions included foraging, resting, basking, mating, etc. We recorded insect IDs to morphological group levels, as many bees are hard to identify to species in the field! We were able to identify common bumble bees, honey bees, butterflies, and a few other insects to the species level, but many were identified to groups for ease (e.g. ‘green bees’, ‘black bees’, ‘leafcutter bees’).

Field Season Stats

Year	# Sample Dates	# Collected Pollinators	# Observed Pollinators
2020	28	2159	6238
2021	33	2471	6225
2022	29	~2000	~4700

Number of sampling dates, total number of collected pollinator specimen (via insect vacuum), and cumulative pollinators observed during 5-minute observations for each of our three field seasons.

Is there a difference in native bee visitation to native plants and their cultivars?

Graphs of cumulative and mean foraging native bees from 5-minute observations conducted over three field seasons. Plant Type (y-axis) is abbreviated with a 6 letter code, e.g. “SYMSUB” = *Symphyotrichum subspicatum* = Douglas’ Aster. Natives have a box around each bar, and cultivars can be identified by an underscore followed by 1-2 letters, e.g., SYMSUB_SN = *Symphyotrichum subspicatum* ‘Sauvie Snow’ = a native cultivar of Douglas’ Aster with white petals.

Our initial graphs show a subtle preference for native types by native bees. Douglas’ Aster, California Poppy, Farewell to Spring, and Columbine (4/7) have higher visitation by native bees when looking at cumulative and mean counts. The difference is marginal for Douglas’ Aster, but trends for the other three plants are strong. The remaining three species (Yarrow, Baby Blue Eyes, Camas) are difficult to assess, based on these figures alone.

Across these seven species, we do see differences in visitation between natives (wild types) and native cultivars. Whether these differences are statistically significant, and whether there is a trend across all plant groups, remains to be seen!!!

Subscribe to the Garden Ecology Blog to receive future updates on native-cultivar research and more news from the lab.

I want to recognize my amazing Bee Team this year, as this field season would not have been possible without them! I am grateful for all of their hard work and their success in managing this project while I was away numerous times this season. They are thoughtful, inquisitive, and resourceful students, all of whom would make amazing lab or field technicians upon their graduation this spring! Nicole is not pictured below, but also deserves recognition for all her contributions to this project. Thank you all 🐝

Svea working on her ultraviolet photography

The Underappreciated Syrphid Fly

Posted on August 23, 2022 by Devon Johnson

A syrphid flying over a clarkia, photo by Devon Johnson

We have been seeing syrphid flies (family: Syrphidae) in great abundance this summer over at the Garden Ecology lab’s research garden, so much so, that our field research team has begun to call it the year of the syrphids! These bee-mimicking, skittish pollinators have particularly loved the native and cultivar yarrow we have planted in our plots. Although their abundance has recently dipped–likely because Yarrow (Achillea millefolium) is done with its first round of bloom–we still see them buzzing around.

Syrphid flies, also known as flower flies or hover flies are a common visitor of gardens. You may see them buzzing around bright flowers or fighting mid air. They are important pollinators and feed off of nectar and pollen in their adult stage. Additionally, in their larval form, they are great at reducing aphid populations, but are extremely susceptible to pesticides.

Line drawing of *Toxomerus* spp. life cycle, credit to Brett Blaauw, Department of Entomology, Michigan State University

The life cycle¹ of syrphids start with the adults laying eggs in leaves of infested plants. After about three days, they hatch into their voracious, blind, larval stage.

The larvae feast on small pests like aphids, leafhoppers, scales, and thrips. The larvae do this by moving along plants, lifting their heads to try and seize and pierce their prey with their triple-pointed dart inside their mouth². After slurping their prey dry, they will discard the exoskeleton.

Larvae will develop through a few instars and after 1 to 3 weeks will go into a pupal stage on the host plant or on the soil. After two weeks, an adult emerges.

Syrphid larvae with an aphid in its grasp. Photo by Oregon State University

Hover fly pupa. Attribution © Adam Grimwade, all rights reserved⁵

In the pacific northwest, our common syrphid is Scaeva pyrastri. It is unique in that rather than overwintering as a larvae, S. Pyrastri overwinters as an adult. Three to seven generations occur in a year, with possibility for the higher counts depending on the region and species. Another species, originally native to Europe, the drone fly (Eristalis tenax³) is named after male honey bees because it is mimics them so well. Other mimics in Syrphidae lay their eggs in the nests of bumblebees or social wasps, where the larvae eat dead bees and detritus.

Their quick movements and bee-like appearance can make syrphid flies hard to identify.

To identify a flying insect as a syrphid, look for a single pair of wings. Flies (Order: diptera) do not have a second pair of wings like bees. Instead they have a vestige of hind wings called halteres that look like little nubs beneath their wings. These act like gyroscopes to help the fly balance during unique in-flight maneuvers. Also look for large, forward facing compound eyes typical of any dipterans. In our lab, we’ve see a wide range of size and different colors. Syrphids can be anywhere from a tenth of an inch to half an inch long, and have black or brown bodies with white or yellow spots and stripes. Fun fact: most hover fly mouths are extendable ‘sponges’ that mop up nectar and pollen.

Common oblique syrphid (*Allograpta obliqu*a). Notice the nub-like halteres below the wings. Photo by Ron Hemberger

Flower flies are extremely important to pest control and pollination, 40% of syrphid species larvae feast on the previously mentioned prey, and each larvae can eat up to 400 aphids during development!

Unfortunately, the larvae of syrphids are similar to many other species so are hard to identify. However, they are usually on pest infested plants and may be seen near adult syrphids. Look for their typical ‘stretching’ behavior while they are on the hunt. If you have a pest problem, avoid using pesticides or insecticides! These kill the syrphids that can help with pests. Instead, promoting syrphids or other pest eaters like ladybugs and lacewings by providing a variety of insectary plants can help you in the long run.

A large syrphid on our native yarrow, with a threat nearby! Photo by Devon Johnson

As previously mentioned, yarrow (Achillea millefolium) has been our most successful syrphid-attracting plant in our lab this year. Syrphid flower preference varies based on the subfamily, according to studies. The subfamily Eristalinae is attracted to white flowers, Pipizinae prefer white and yellow, and Syrphinae is more general. Link to an article going more in depth on syrphid flower preference here⁴.

Not coincidentally, native yarrow is primarily white, while our cultivars are yellow and pink. Observationally, syrphids visit yellow yarrow at a similar rate as they do the native, while our pink cultivar saw next to no syrphid visitors. We recommend planting yarrow as well as a variety of native flowering plants to support these pollinators. Leave leaf litter and debris around flowering plants, too. These provide protected overwintering sites which syrphids rely on⁷.

Syrphid on our yarrow ‘Moonshine’ cultivar. Photo by Devon Johnson

Currently, no syrphid species are on the U.S. Endangered Species Act lists, but like many insects, this underappreciated pollinator is understudied and biodiversity of this group is not well tracked. In Britain, however, some hoverflies have been placed on their Biodiversity Action Plan.⁶

Whether syrphids are endangered or not, we can help biodiversity by promoting native pollinators and planting native plants in our yards and gardens.

Credits

No Mow May

Posted on April 26, 2022 by Jen Hayes

Cartoon: Seppo Leinonen, www.seppo.net/e/

A short story about grass

Lawns are perhaps one of the most controversial spaces when it comes to improving landscapes for wildlife. When I was in college, I threw myself head first into becoming more “green”, which for me meant being the best environmental and eco-friendly entomologist I could be. That meant changing not only my own habits, but those of my parents who, fortunately for me and maybe less fortunately for them, lived only thirty minutes away from my university.

It started with composting. After we got over the discussion about how to properly care for an indoor bin to avoid fruit flies AND my mom saw how much deliciously rich soil her dear friend yielded from her own bin, composting was a hit. My mom still tells me how amazed she is by how quickly the pile reduces every spring. I’m still surprised as to how easy of a practice it was for them to adopt.

The topics that came next were bees, buying local, what organic means, reusable everything, why you should check the insulation on the house before even thinking about buying solar panels, and then, after I took two landscape design courses, we approached the topic of grass. For this talk, which actually spanned months, I came prepared with books, quotations, and 3 or 4 finely detailed maps with elaborate plans for turning my parent’s yard into a pollinator sanctuary.

I began with dropping hints that this talk was coming. I would casually add “lawns should be like area rugs, not wall to wall carpeting” into a conversation, or post graphics like the one at the beginning of this blog on Facebook, and tag my parents in it. I even gave my dad Noah’s Garden: Restoring the Ecology of our Own Backyards by Sara Stein for Father’s Day. I knew this was a change that would take a lot more time than the compost.

Truthfully, I started with my mom. She’s the outdoor gardener, my dad is the houseplant guy. And, as anyone who has ever been a child knowns, there’s always one parent or guardian you go to first for the more difficult requests. For the most part, my mom was excited to see me become a budding naturalist. Around the house or on hikes I would point out plants I now knew the names of, and together we would assess the basal leaves of new garden growth, trying to figure out what in the world did she plant next to the lupine in the garden last year. When I got my wisdom teeth removed, she and the nurse patiently waited while I explained how to identify the red oak next to the car from other common oaks planted as street trees. I made it my mission to make my mom a budding naturalist, too.

My mom and I putting together a raised garden bed last summer (2021).

When my landscape design class ended, I took my mom on a tour of her property, pointing out all of the potential diversity their landscape could support if they turned it into something beyond grass. I described the changes I recommended, I explained the benefits of the rain gardens, the swales, the terraced lowbush blueberries for the front yard, the beautiful meadow that would grow in the seasonal wet spot in the backyard and enhance the firefly populations we see glowing in the summer. I explained that though the initial transition would take a lot of work, the result would be significantly less maintenance for them, and they would sit atop the ecological design of my dreams. And there would be so much less lawn, err grass for them to mow.

Nearly 10 years later, I am reluctant to report that the quantity of grass covering my parents’ landscape remains relatively similar. The problem with my plan? I went too big. If mom was not ready to completely transform 3.5 acres, then dad certainly would not be either. Though they both appreciated and complemented my thoughtfulness and the rigor behind my design work when I reviewed it with them, my bold idea of turning the yard into a part pick your own blueberry farm and part pollinator paradise certainly scared them from asking my opinion on any further garden projects for a while.

I refused to let this setback alter my new found passion for increasing the value of my childhood home (to wildlife). I continue to share information with my parents, but in small doses rather than in huge design plans. My mom happily adds native plants we pick out together to her gardens and excitedly reports back about the bees she sees visiting them. They’ve added a small planting of mint outside the kitchen to keep the ants at bay, and when it comes to the lawn, they don’t mind leaving the dandelions and other wildflowers (“weeds”) for wildlife to snack on in the spring. And they’re not afraid of asking my advice on new plants or yard projects, though they don’t always utilize it.

Perhaps the most important result of my collegiate mission for Making the Hayes Family Eco-Conscious was helping my parents to see their yard differently, to help them see the potential that exists underneath all of the grass. I hope part two of this blog post might make you do just the same.

Dandelions covering a field in Northern Vermont

No mow May & reimagining our yards

No mow may is an initiative that started in the United Kingdom and has since spread to numerous other countries. To participate is relatively simple: don’t mow your lawn for the month of May. The goals of the initiative include increasing forage for pollinators and other wildlife, and creating awareness about the negative ecological impact of intensively managed lawns.

The practice of reducing mowing to promote diversity is supported by research. A meta-analysis of studies from North America and Europe found that both plant diversity and invertebrate diversity is higher in urban lawns with a lower mowing intensity. This increase in diversity was true regardless of mowing height or frequency, and the authors also found that weeds and invertebrate pests occurred in higher quantities with intensive mowing in many Northern regions.

In terms of surface area, the largest irrigated crop in the United States is lawn. Our idyllic front and backyard monocultures have been cultivated as such to meet the dominant neat and tidy aesthetic. This aesthetic has been so deeply wound into our culture that untidy yards are accused of being a sign of disrespect to one’s neighbors. The impact is such that if you choose to maintain a yard outside of this aesthetic, you have defend yourself against your neighbors with signage.

Courtesy of The Bees Weeds on Etsy
Courtesy of the Xerces Society
Courtesy of the National Wildlife Federation
Courtesy of the Xerces Society

Perhaps some of this discomfort with weedy yards is due to misinformation- common wildflowers like dandelions, goldenrod, and even sneezeweed have poor reputations because they are thought to cause seasonal allergies. Insect-pollinated plants, which all three of these happen to be, actually shed very little pollen into the air. These plants have co-evolved with their insect pollinators, such that insect-collected pollen grains are actually often larger and/or heavier than those of wind-pollinated plants, and as a result, their pollen cannot easily drift into our respiratory tracts. Many tree species and grasses (which we in the Willamette Valley know all too well about) are more likely to be the culprit for seasonal pollen allergens.

Whether it’s the allergens, the HOA, city standards, your landlord, your own personal preference, or societal pressures that encourage you to keep your yard tidy, there are many small ways in which to increase the productivity and diversity in your landscape. One option is No Mow May- committing to the whole month, or even part of it, to increase the availability of flora to early emerging invertebrates. Reducing mowing frequency is another option, or mowing around weeds like hedge nettle, creeping Charlie, heal-all and others that you may find some insects foraging on. Or perhaps you can replace a small section of lawn a native plant garden, or butterfly garden, or plant some giant sunflowers for the birds.

**Left**: Photo by Raquel Gilliland. **Center & Right:** Photos © Saxon Holt / PhotoBotanic.com

I have compiled a few resources related to No Mow May below, in addition to some more “neighborly” ways you can begin changing your own yard’s aesthetic. If you decide to go No Mow May, we’d love to hear about your experience!

“A weed is a flower in the wrong place” – Ian Emberson

Resources

Plantlife: No Mow May
Bee City USA: No Mow May
PennState Extension: Neighborly Natural Landscaping in Residential Areas
Buzzing and Beautiful: Designing Pollinator Gardens with OSU Extension
OSU Extension: Enhancing Urban and Suburban Landscapes to Protect Pollinators
A Tribute To The Monarch Butterfly: How to Turn Your Backyard Into a Butterfly Friendly Habitat
Fine Gardening: Defining the New American Cottage Garden (my personal favorite aesthetic!)
www.healthyyards.org

**Left**: original source unknown. **Right:** Sourced from healthyyards.org

What are bees doing right now? Spring edition

Posted on April 13, 2022 by Mallory Mead

It’s early spring and the trees have begun leafing out. Colorful flowers are springing from the ground, and the landscape is slowly coming to life with insect activity. In this post, I’ll highlight some of Oregon’s ubiquitous spring bees, what they are up to, and how to easily recognize them.

Queen bumblebees are emerging from their winter burrows under leaf litter and forest duff. They zoom by with boisterous buzzes. Queen bumblebees are sturdy and furry, and can power through wind, rain and cold better than any other type of bee. Queens are much bigger than the workers that will come once the queens find nest sites and begin laying eggs. For now, they work alone, preparing to lay their first set of worker eggs.

If you see (or hear) any queen bumblebees this spring as they scan the sparsely blooming landscape, they are most likely looking for a proper nest site, finding nectar to energize this search, or, if one has already found her nest, she may be collecting pollen to feed her developing worker offspring.

A rain-drenched Yellow-faced bumble bee on Oregon Grape. Photo by Jen Hayes.

A female mason bee has brought bright yellow pollen to her nest. Video by Jen Hayes.

Mason bees (Osmia lignaria) are a cherished Oregon spring bee active from March to early June. Look closely in a bee hotel for a chance to observe mason bees in action!

Male mason bees emerge first from their pupal cocoons. You might see them patrolling bee hotels waiting for a female to chase down. When the females emerge a little later, they mate and then begin their work provisioning nests with pollen balls and eggs. An individual female has a short lifespan living only about 20 days, but in this time, she may provision anywhere from 2 to 7 nest holes each containing many offspring cells.¹ Quite the busy bee!

Andrena is a genus of mining bees that are some of the earliest risers when it comes to spring emergence. They are a diverse group of small, furry, ground-nesting bees that are only active for a few weeks out of the year. Andrena are solitary bees, but can be seen foraging and mating in droves on early blooming fruit trees like cherry, apple and pear. Last spring, I watched hundreds swarm this cherry tree to collect nectar and mate.

Andrena in cherry tree (captured with magnifying lens). Photo by Mallory Mead
Andrena mating pair. Photo by Mallory Mead.

Spring Bee Quick ID:

Now, let’s identify some of the bees you may see out and about on sunny spring days when the wind is low. We’ll start with the most conspicuous group – the bumblebees. Bumblebees are the biggest and the loudest bees on the landscape, covered in a thick coat of fuzz. Here’s how to recognize the 3 most common species of bumblebees you’ll see in the Willamette Valley in early spring.

Bombus vosnesenskii or the “yellow-faced bumblebee” is by far the most common bumblebee in this region. It is recognized by the yellow fuzz on its face and yellow band near the distal end of its abdomen.

*B. vosnesenskii* foraging on butterfly bush. Photo by Mallory Mead.

*B. melanopygus* queen foraging on Wartleaf Ceanothus. Photo by Mallory Mead.

Bombus melanopygus, the “black-tailed bumble bee” is another of the earliest Bombus species to emerge. You can identify this bee by the orange band in the middle section of its abdomen!

Bombus mixtus, the “fuzzy-horned bumblebee”, tends to emerge a little later than the previous two species, and has orange hair on its lowest abdominal segments.

*B. mixtus* flies amid borage plant. Photo by Mallory Mead.

Mason bees can be recognized by their deep iridescent blue-green color, that sparkles in the sun. Males are distinguished from females by their small size and the yellow mustaches found on the front of their faces. Females lack the yellow tufts and are larger than the males but smaller than a honey bee. They carry pollen on the underside of their abdomen which is a trait unique to their bee family, Megachilidae.

Andrena are a diverse group that are tricky to identify. They can be distinguished from other small, furry bees by the presence of velvety hairs between their eyes and the middle of their face called “facial fovea”.²

Facial Fovea. Photo from the ODA Bee Guide

They also carry pollen on their hind legs and on hairs between their abdomen and thorax, which distinguish them from bees in the Megachilidae family.

We hope this little guide will help you experience the native bees in your landscape this spring that make the pollen go round.

Thank you for joining us on this exploration of Oregon’s spring bees and what they are currently doing! We will release two more blog posts in this series, one for each of the four seasons. Blogs will be posted during their prospective seasons, so be sure to subscribe so you don’t miss the next in the series!

Scrub a Dub Dub: 5 Cleaning Tips for a Healthy Garden!

Posted on March 1, 2022 by Nicole Bell

What… is it already time to think about spring cleaning?! It might still be winter, but spring will be here faster than we know it. Some quick cleaning is a great way to take care of a garden that we enjoy during the year!

If you’re wondering where to start, this blog post could be a way to jumpstart your cleaning. Here’s 5 tips on things to clean in the garden.

Bird feeders.

It’s a great feeling to see all types of birds using and enjoying your bird feeder. While they’re great, bird feeders can actually pose a major threat to bird health: excrement that is on the feeder perch can pass from bird to bird, spreading Salmonella and other diseases. Even if you don’t see dead birds around your bird feeder, birds that use your feeder could still be passing disease elsewhere, after they use it. Luckily, it’s a simple fix! How to clean a bird feeder: It’s best to clean your bird feeder regularly, say in between fills. Ideally, take it inside and wash it with soap and water. Then, soak it in a bleach solution (9:1 water to bleach) for 10 minutes. Rinse again to rid the feeder of any bleach solution. Make sure to wash your hands after touching the feeder! For more information, check out this link.

Bird baths.

Bird baths: Algae isn’t fun to look at, but did you know it’s also dangerous for birds? Luckily, there’s simple fixes to keep bird baths clean and fresh for visitors! The easiest way to help keep your bird bath clean is to wash it out regularly (sometimes even every day, especially in the summer).

There are two other mixing solution options for doing a deep clean of your bird bath: vinegar or hydrogen peroxide. Each mixture is nine parts water and one part vinegar or hydrogen peroxide. Use a scrub brush to fully clean the bath and then ensure no cleaning mixture remains. Refill with water, and you’re good to go!

For more information, check out this link.

Gardening tools.

Tools help us take great care of the garden… let’s show the same level of care to our gardening tools! Cleaning gardening tools helps to extend their lifespan and can also help prevent the spread of disease.

How to clean gardening tools: Different options exist to clean gardening tools. For those tools that have metal, you can fill a 5 gallon bucket with sand and about a quart of car motor oil. After you’re done using the tools for the day, dip them in the sand and oil mixture. This mix helps to both clean the blade and coat it in a thin layer of oil. If you want to do a deep clean, you can wipe off any tools with a damp rag and some alcohol. If there’s sap or other buildup on your tools, try using sandpaper to get rid of it. Sandpaper is also a great way to refresh the wooden handle on tools (if you want to add a layer of oil after sanding wood, try mineral oil as a finish)!