We Study Gardens

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We study gardens: the plants, insects, animals, people, decisions and management practices that either improve or degrade a garden’s ability to promote environmental and human health.

An underlying premise of our work is that gardens are important and understudied systems, that are key to building more sustainable, healthy and just communities.

The Garden Ecology Lab, January 2021. Top Row: Max, Gail, Tyler; 2nd Row: Signe, Jen, Aaron; 3rd Row: Izzy, Gwynne, LeAnn; Bottom Row: Mykl. Missing: Cara and Mericos.

 

Our garden pollinator work is supported by a generous donation from Spike Wadsworth and Y. Sherry Sheng.

Biodiverse Gardens Can Improve Bee Nutrition and Reduce Bee Disease

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!

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.

What happens to the bees we catch?

Insect collections are a good hobby to have, and an even better tool for research. One might think you just go catch insects and pop them into a box, but a little more needs to happen in order to preserve them for a collection.

Depending on your collection method, washing, blow drying, pinning, and labelling all need to happen to keep our collection usable!

After doing these steps and putting them in a box, our wonderful Jen Hayes and taxonomists will identify them to species. There are so many morphs and intricacies that you may not even realize two look-alike bees may just be completely different species. My favorite thing about the process is seeing the fluffy bumblebees after blow-drying! 🐝

Anyways, here’s a short video showing how we go from catch to box!

Video and music made by Devon Johnson

2022 Field Update: Native plants & native cultivars

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)

PhotoScientific NameCommon NamePlant Type
Achillea millefoliumYarrowNative

Achillea millefolium

‘Calistoga’*
YarrowCultivar

Achillea millefolium

‘Salmon Beauty’
YarrowCultivar

Achillea millefolium

‘Moonshine’**
YarrowCultivar
Aquilegia formosaWestern Red
Columbine
Native
Aquilegia x ‘XeraTones’Cultivar (hybrid)
Camassia leichtliniiGreat CamasNative
Camassia leichtlinii
‘Caerulea Blue Heaven’
Great CamasCultivar
Camassia leichtlinii
‘Sacajawea’
Great CamasCultivar
Symphyotrichum
subspicatum
Douglas’ AsterNative
S. subspicatum
‘Sauvie Sky’
Douglas’ AsterCultivar
S. subspicatum
‘Sauvie Snow’
Douglas’ AsterCultivar
Clarkia amoenaFarewell-to-springNative
Clarkia amoena
‘Aurora’
Farewell-to-springCultivar
Clarkia amoena
‘Dwarf White’
Farewell-to-springCultivar
Clarkia amoena
‘Scarlet’**
Farewell-to-springCultivar
Eschscholzia
californica
California PoppyNative
E. californica
‘Mikado’
California PoppyCultivar
E. californica
‘White’
California PoppyCultivar
E. californica
‘Purple Gleam’**
California PoppyCultivar
Nemophila menziesiiBaby Blue EyesNative
(California)
N. menziesii
‘Penny black’
Baby Black EyesCultivar
N. menziesii
‘Snow White’
Baby Blue EyesCultivar
Sidalcea asprella
ssp. virgata***
Rosy checkermallowNative
Sidalcea malviflora
‘Purpetta’***
Cultivar
Sidalcea malviflora
‘Party Girl’***
Cultivar
*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

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
20202821596238
20213324716225
202229~2000~4700
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 🐝

What are bees doing right now? Fall Edition

The sunny days are diminishing as summer rolls into autumn, and as the sun descends, the bees’ flight lulls to rest. Bees sense and respond to light and use the sun to orient themselves and navigate. Along with their two large compound eyes that are used for vision, bees have three simple eyes that sit atop their their heads in a triangular formation. These are called ‘ocelli’ and they sense light.

Originally posted by postgraduate student Hamish Symington, this video shows bees being studied by fellow student Kristina Buch in the Cambridge University Botanic Garden.
Ocelli can be seen atop the head between the compound eyes. Photo of bee from the genus Triepeolus by Mallory Mead.

There is a video circulating the internet of honeybees flying in an enclosure in a laboratory. The video shows the researcher turning off the lights in the enclosure, causing the bees to drop to the ground instantaneously, showing how honeybees will not fly in the absence of light.

We notice similar behavior in the field on days where clouds pass over the sun intermittently. When the sky is bright, our plants bustle with pollinators, and when shadows come over, most bees are suddenly out of sight. It makes sense that as the days get shorter and colder the sight of pollinators will become more and more fleeting!

Some bees are still coming out during the warm October afternoons, and collecting their final energy reserves for the winter. Goldenrod, Douglas’ aster, California poppy, bee balms, and black-eyed Susan, amongst other late blooming pollinator plants are still providing bees with nectar and pollen during this time of transition.

During this season, honeybees and bumblebees predominate the landscape, while long-horned bees (genus: Melisoddes), leafcutter bees (genus: Megachile) and sweat bees (family: Halictidae) can still be seen as they finish up resource collection in the Willamette Valley.

Social bees

Honeybees must make enough honey before temperatures drop and they can no longer leave the hive, so you’ll find them foraging for pollen and nectar as late in the season as possible.

In late summer and fall we begin to see an influx of bumblebee queens. During the summer, the queens are busy reproducing in their underground hives, while worker bees take to the landscape. However, near the end of the foraging season, new queens hatch and fly out to find mates and food. You may see bumblebee queens getting their last bits of food energy before overwintering, while the rest of the colony (males and workers) dwindle away.

Black tailed Bumble Bee (Bombus Melanopygus) © Erin Forrester, some rights reserved (CC-BY-NC)

Check out this guide to Bumble Bees of the Western United States to see which Bombus species are found in your region and what time of year they are active.

Solitary Bees

Many solitary bees are finishing their last nests where they’ve laid eggs for the next generation of their species.

If you care for nest boxes in your garden be sure to take appropriate steps to bring your bees indoors and clean their cocoons. Check out the Linn Master Gardener Association Bee Notes email list to receive timely emails about the seasonal steps of caring for mason bees.

When solitary adult bees finish reproducing and nest building, their work is done, so they die off. But small carpenter bees, from the genus Ceratina, are an exception. Ceratina females remain as late into the cold season as they can muster in order to guard their nests.1 These protective mothers fend off predators, pests and parasitoids that try to invade the nests.

Ceratina acantha © vespidmacro, some rights reserved (CC-BY-NC)

This fall, we hope you are able to see some of the last glimpses of bees of the year!

This post concludes our series on what the bees are doing right now! Thank you for taking part in this seasonal journey through the lives of bees in the Willamette Valley.

Source Cited:

1: Danforth, B. N., Minckley, R. L., & Neff, J. L. (2019). The solitary bees: Biology, evolution, conservation. Princeton University Press.

Celebrating Garden Ecology Lab Group Accomplishments!

These past few months have been filled with great news, for so many members of the Garden Ecology Lab team. In this post, I wanted to take a moment to celebrate their great work and accomplishments.

Aaron Anderson successfully defended his dissertation in February 2022, entitled Evaluating the Attractiveness of Pacific Northwest Native Plants to Insects and Gardeners, and graduated with his Ph.D. in horticulture. In September 2022, Aaron also published two chapters of his dissertation. This first is an Extension publication, geared towards gardeners: ‘Native Plant Picks for Bees‘. The second is the scientific paper that formed the basis of the Extension publication: ‘The Bee Fauna Associated with Pacific Northwest (USA) Native Plants for Gardens‘. Aaron is now working with the Xerces Society, as Pesticide Program Specialist.

Aaron at the spring 2022 OSU graduation ceremonies, awaiting official conferment of his Ph.D. degree!

Jen Hayes successfully advanced to Ph.D. candidacy in June 2022, by passing her comprehensive exam. The comprehensive exam (also known as ‘comps’) is perhaps the most difficult part of the Ph.D. journey. In Jen’s case, it involved a 3-hour long oral exam with her graduate committee (Drs. Lauren Gwin, Jim Rivers, Andony Melathopolous, Ryan Contreras, and Gail Langellotto), who took turns asking a series of questions on topics ranging from wild bee biology, native plant ecology, and ornamental plant breeding. Jen also prepared and defended a review paper focused on the process and impacts of breeding native plants to produce native cultivars. Jen also recently completed the prestigious ‘Bee Course’ offered by the American Museum of Natural History, at the Southwestern Research Station in Portal, AZ.

Jen Hayes advanced to Ph.D. candidacy in June 2022, and participated in the AMNH Bee Course in August 2022.

Signe Danler was promoted to Senior Instructor I, after thorough review of her accomplishments by the Department of Horticulture and the College of Agricultural Sciences. Signe manages the Certificate of Home Horticulture online course series, and also develops and provides online short courses to support Master Gardener training efforts across the state. Over the course of her career at OSU, she has created three new online classes (Sustainable Landscape Management, Sustainable Landscape Design, and Gardening with Native Plants), and has updated and revised an additional nine classes. Her efforts have grown revenue, so that her position is now fully funded, and also contributes to the operating expenses of the Garden Ecology Lab.

Signe Danler was promoted to Senior Instructor I at OSU, in June 2022.

Mallory Mead received two prestigious scholarships! First, she received the Garden Club of America’s Mary T. Carothers Summer Environmental Studies Scholarship, to support her work on the Clarkia Project. Mallory also won a Scholar’s Award from the American Society for Horticultural Science, in recognition of her scholastic achievement.

Mallory Mead, in a field of wild Clarkia species, the focal organism of her undergraduate research thesis.

LeAnn Locher led teams of Extension professionals that received two awards from the Association for Communication Excellence. LeAnn and team earned a Silver in the category of ‘Social Media Campaign (Organic)’, for a series of social media posts (and supporting peer-reviewed web materials) focused on supporting gardeners through extreme heat events. One web post was focused on identifying and preventing heat stress in plants. Another was focused on helping bees during a heat wave. A third post focused on helping hydrangeas through the heat wave. LeAnn and team also earned a Bronze in the category of ‘Social Media (Single Item)’ for a social media post (and supporting peer-reviewed web article) focused on stopping the spread of jumping worms during plant sales and trades. LeAnn conceived of the campaign, and designed the visuals and outreach strategy. She worked closely with other team members to quickly develop peer-reviewed web articles that could support the social media posts. LeAnn’s excellence in communications and outreach was also recognized via her receipt of the 2021 Oscar Hagg Extension Communication Award.

LeAnn Locher received the 2021 Oscar Hagg Extension Communications Award, and two 2022 awards from the Association for Communication Excellence.

Svea Bruslind received a 2022 Art-Sci Student Fellowship to support her ‘Bee’s Eye View’ project. This fellowship will allow Svea to display her work in her first-ever art exhibition! Gail is serving as Svea’s scientific mentor for this fellowship. We are beyond honored that Jasna Guy is serving as Svea’s artistic mentor!


Tyler Spofford graduated from our lab group in 2021, and was soon thereafter hired as the new SNAP-Ed Gardening Program Coordinator, working with our colleagues in the College of Public Health. In this role, Tyler will continue to build out the gardening resources in Food Hero, and will also help administer and manage the Seed to Supper program at OSU. You might remember that Tyler completed his undergraduate thesis research on containerized gardening in the Garden Ecology Lab.


Help me congratulate this amazing team of scientists, educators, communicators! I am lucky to work with such a great team.

The Underappreciated Syrphid Fly

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
Syrphid egg. Photo by E. Beers
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.

Drone fly (Eristalis tenax), photo by Magnus Hagdorn8
S. Pyrastri, photo by Ron Hemberger

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 obliqua). 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

  1. https://biocontrol.entomology.cornell.edu/predators/syrphids.php#:~:text=Syrphid%20fly%20larvae%20are%20slug,to%2018%20mm%20in%20length.&text=Adult%20flies%20visit%20flowers%20and%20feed%20on%20nectar%20and%20pollen.
  2. http://treefruit.wsu.edu/crop-protection/opm/syrphid-flies-hover-flies
  3. https://www.fs.fed.us/wildflowers/pollinators/pollinator-of-the-month/flower_flies.shtml
  4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6282941/
  5. https://www.inaturalist.org/photos/69587430
  6. https://hub.jncc.gov.uk/assets/98fb6dab-13ae-470d-884b-7816afce42d4#UKBAP-priority-terrestrial-invertebrates.pdf
  7. https://www.houzz.com/magazine/this-fly-is-one-of-the-most-beneficial-insects-around-stsetivw-vs~34189485
  8. https://www.flickr.com/photos/hagdorned/12863647073/

New Summer Game- Pollinator Bingo!

Summer pollinator Bingo board!

We are entering the heart of summer, with blue skies, rising temperatures, blooming flowers, and growing gardens. As some of us are taking this time to relax in the bounty of our gardens and in whatever shade we can find, our pollinator counterparts are in the middle of their busiest season. The pollinators are out in full force, and it seems almost impossible to turn around in a garden without spotting a new butterfly, bee, or beetle. So for those among us who want to engage even further with the friends visiting our gardens around this time of year, we have the perfect game for you: Pollinator Bingo! 

Our Pollinator Bingo-or should we say BEEngo- is a healthy mix between Bingo and a scavenger hunt! 

Here’s how to play:

  1. Select the Bingo Card you will use 
  2. Download it, or print it out, and get it ready to be filled out 
  3. Keep your eyes open for these visitors in a garden. When you spot a pollinator on your Bingo card, mark that pollinators square. 
  4. Once you fill an entire row (horizontal, vertical or diagonal) you’ve won your BEEngo!  
  5. Extra Credit Challenge: Try to black out the entire card! 

We hope you have fun playing Pollinator Bingo outside, exploring and enjoying the natural world in some way. Good luck BEEngo players! 

Below, we included some pollinator spotlights, so you can get to know some of the species on your Bingo card a little better!

Pollinator Bingo Spotlight List:

  1. Tribe Eucerini, Longhorned bee

Eucerini, also known as long-horned bees, are favorites among our lab members. They are the most diverse tribe in the family Apidae, with over 32 genera. These bees are solitary and ground-nesting. What makes them distinct and a lab favorite are the long antennae the males are known for and from which they get their common name. The females are also recognizable, as they have long hairs, known as scopae, on their hind legs, giving them the appearance of wearing very thick pants. 

Photo by Svea Bruslind

2. Species Papilio machaon oregonia, Oregon Swallowtail butterfly 

As with any in the Swallowtail family, Papilio machaon oregonia, or the Oregon Swallowtail, is big, beautiful, and eye-catching. It was officially named Oregon’s state insect on July 16, 1979. It is native to the northwest and is only found in Oregon, Washington, Idaho, and sections of British Columbia. For the purposes of Pollinator Bingo, any Swallowtail will count for its space. Keep an eye out for the Oregon Swallowtail and others, and see how many different species you can find!

Photo by Cara Still

3. Family Syrphidae, Flower Fly 

Hoverflies, flower flies, and syrphid flies are all different names for the flies within the family Syrphidae. Syrphid flies come in a wide variety of sizes and colors, with some that resemble wasps and others that look nearly identical to bees. Most syrphids, however, can be found with some kind of striping on their abdomen.  Syrphids are essential to any garden as they help with pest control and pollination. Some people are surprised that flies are pollinators too, but hopefully, this list can illustrate the wide variety of pollinators out there! 

Photo by Devon Johnson

4. Species Trichodes ornatus, Ornate Checkered beetle 

Trichodes ornatus, or the Ornate Checkered beetle, is an interesting species, as during the early stages of its life, instead of pollinating, it feeds on pollinators. These beetles will lay their eggs on plants such as yarrow, sagebrush, and asters. When these eggs hatch, the larvae attach themselves to a visiting bee, usually a leafcutter bee. They will then be transported to the bee’s nest, where they will eat the provisions left there for the host larvae before eating the host larvae and burrowing into nearby cells to do the same. As an adult, the Ornate Checkered beetle will feed on pollen but will not miss an opportunity to snack on other visiting pollinators when foraging for pollen.

Attribution © LapisOre some rights reserved (CC by lapis_the_mothman iNaturalist user)

5. Species Calypte Anna, Anna’s hummingbird

Calypte Anna or Anna’s hummingbird should be a familiar sight for many of us. This rambunctious bird is a permanent resident along the Pacific Coast, staying year-round through winters instead of engaging in migration as other species of hummingbirds are known to do. Males of Anna’s hummingbird are pretty talkative, often vocalizing with a buzzy song. The males have a brilliant red head with a green body, and the females have similar green plumage, but without the red coloration on their face and neck. 

Attribution © selwynq some rights reserved (CC by selwynq iNaturalist user)

What are bees doing right now? Summer Edition

Graphic by Jen Hayes

Summer is the main active season for many bee species. After a wet spring in Western Oregon, the sun is out and our world is in bloom!

So what are summer bees up to right now? The main events of the season are…

  • Foraging for nectar and pollen
  • Finding mates and laying eggs
  • Excavating, finding and building nests for offspring.

Adult bees also experience predation by spiders and birds during this time. This Crab Spider caught a female long horned bee in its jaws!

A female long horned bee caught by a crab spider on Douglas’ Aster.

So who exactly is out and about in your garden at this time of year?

Bumblebees and honeybees visibly dominate the landscape throughout the summer, but lean in closer to your flowering plants and you’ll find the smaller sweat bees (family: Halictidae), long horned bees (genera: Melissodes and Eucera), leafcutter bees (genus: Megachile) and small carpenter bees (genus: Ceratina). Although there are many others amid the vast diversity of bee species science is only beginning to understand, these are some common garden visitors. We’ll go through each group and their summer activities.

Notice the two adomenal segments beneath the yellow stripe of this male yellow-faced bumblebee (Bombus vosnesenskii). Photo by Jen Hayes.

The presence of pollen on a bee especially carried in pollen baskets, is a good indicator that the bee is a female. Photo by Jay Stiller-Freeman

Bumblebees: By summertime, most queens have established colonies of workers who do the foraging for the hive, so we see less large queen bumblebees and more smaller workers as the season progresses. Later in the season, queens lay male eggs as well as eggs for the next generation of queens. Male bumblebees take to the landscape in mid to later summer, recognizable by their additional segments on their abdomen, long antennae, and by the fact that they don’t carry pollen like females do. Males do not have stingers, so if you can confidently identify male bumblebees, they are fun to play with while they’re waiting around for new queens with which to mate. You’ll find them sipping on nectar-rich plants like lavender, herbs, asters and heal-all.

Honeybees: Summer is prime time for honeybees! Worker populations are at their peaks; pollen and nectar are flowing. As hive population size rises and available hive space remains static, honeybees may organize a swarm. In this process, the current queen lays new queen eggs and part of the colony joins her to lift off and leave the colony in search of a new cavity to make their home. Swarming is considered a form of colony-level reproduction supporting the idea that honey bee colonies are super organisms. Swarming is common in spring and early summer. Beekeepers add new boxes to hives so prevent their colonies from swarming.

Late summer is mating season for honey bees. Males and new queen eggs are laid and emerge to mate with individuals from other colonies. Honeybees mate in the air at heights ranging between 15 and 60 m1.

A yellow-faced bumble bee and a honey bee sip nectar from lavender. Photo by Devon Johnson.

Sweat bees

Sweat bee on California Poppy ‘White’. Photo by Tyler Sato Spofford.

A halictid dear to our hearts at the Garden Ecology Lab is the metallic green bee (genus: Agapostemon). While females provision nests in the soil, you can find males resting in congregations on flowers in the evening time and early morning!

Sweat bees are one of the most common groups of “small” bees you’ll find in your garden. They forage on a wide variety of plants and come in a wide range of sizes, but most have striped abdomens, and all carry pollen on their hind legs and nest in soil.

Agapostemon virescens male congregation.
A male long horned bee from the genus Eucera on a California Poppy ‘Purple Gleam’. Photo by Jen Hayes.

Long Horned bees

Long horned bees are most active on our research plots in the mid to late summer. I love this group because they are so easy to recognize. Males have antennae that are way longer than other bees’ relative to their bodies. The females, who bear antenna of normal lengths, are still easy to spot because they have long feathery scopa (or hairs) on their hind legs for collecting pollen that they absolutely pack with pollen while foraging.

Long horned bees are sometimes referred to as “sunflower bees” for their love of foraging on sunflowers.

Long horned bees nest in the soil2, so when you see them take it as a reminder to leave some uncovered, undisturbed soil in your garden for these bees to persist!

Notice this female long horn’s feathery pants! Photo by Mallory Mead.
A relatively large small carpenter bee. Photo by Mallory Mead.

Small Carpenter bees

When I point out small carpenter bees (genus: Ceratina), most of my friends can’t believe they are bees. They think they are some kind of flying ant. Their bodies are sleek, and often shimmer with a green or blue reflective gleam.

Small carpenter bees are considered wood excavators as they dig out the pith from dry plant canes for their nests. Ceratina are a unique group in terms of their parenting style. Unlike other solitary bee mothers, Ceratina mothers guard their offspring even after their offspring have developed into adults. Mothers stick around as long as they can until Winter falls.2

Leafcutter bees

Leafcutter bees (genus: Megachile), as their names suggest cut leaves from their host plants! They use these bits of leaves to line their ground and cavity nests, to waterproof and protect their offspring.

Leafcutter bees are from the bee family Megachilidae, a family known for creative nest building. Bees in this family were supposedly able to expand their ranges due to their flexibility in nesting site and material. They’ve been found nesting in wood, porous stones, stems, galls, and even snail shells filling these various cavities with leaves, mud, plant resins, pebbles, straw and even petals2. The fascinating nest building behavior we’ve gotten to witness in the field is petal cutting of Farewell-to-Spring (Clarkia amoena) blooms.

We can track the usage of Farewell-to-Spring petals by leafcutter bees due to the signature crescent shape left behind on the flowers.

Thank you for joining us on this exploration of some of Oregon’s summer bees and what they are currently doing! We will release one more blog post in this series. Be sure to subscribe so you don’t miss the next in the series!

Sources

1: Landscape Analysis of Drone Congregation Areas of the Honey Bee, Apis mellifera by Galindo-Cardona et. al, 2012. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3635128/

2: The Solitary Bees by Bryan N. Danforth, Robert L. Minckley, and John L. Neff. 2019.

New Lab Member: Devon Johnson

My name is Devon Johnson, and I am a senior undergraduate crawling ever so gradually towards a degree in Biology with an option in Ecology. I’ve lived in a few different places, but my love of natural sciences bloomed in Oregon. I recently joined the bee team to help at Oak Creek as a field and lab tech. This is my first research related job and I have quickly learned a host of bee and plant knowledge I never knew I wanted!

I volunteer at Chintimini Wildlife Center every Thursday, where I get to see wildlife get nursed to health. We mainly get birds, so I love hearing the quirky calls and chirps, and most importantly, see the personalities of each patient. The experience has wholly made me a bird fan, and I love learning and talking about them. (Bird facts are the best!).

A cattle egret I shot and identified with iNaturalist (what an amazing website!)

I took a biodiversity class one year, which solidified my dream to get involved in conservation biology. I’ve learned about wonderful conservation projects, such as the Y2Y (Yellowstone to Yukon) project, that inspire me to continue my studies to grasp as much as I can about the wonderful world we live in. Biology is so entrancing, and as I absorb information about fungi this summer through a class I realize that I am right at home within it.

After trying to catch dragonflies in nets with the team (it went disastrously), I was determined to at least get a good shot of one.

While I will continue to become more knowledgeable about pollinators, data collection, and native plants this summer, my current favorite fact that I didn’t know about the bee family Apidae (bumblebees, honey bees) is that they keep the pollen they are collecting in a “pollen basket” called corbicula, or corbiculae for plural.

Let me say it again- pollenbasket.

If you don’t love bees now then I can’t help you.

I appreciate everything that the Oak Creek Team has taught me so far, the team has been so welcoming, and am glad to be here!