Pollinator Week 2022

Happy pollinator week and first official week of summer! ☀️🐝🦋

Pollinator week is an annual celebration in June to emphasize the importance of pollinators and their health, started by the Pollinator Partnership. To celebrate pollinator week, we’re going to share some information with you about a few of our favorite pollinators and a few others deserving recognition. June is also Pride Month, so we are going to start with a fun fact connecting pollinators and Pride!  🌈

Did you know there are pollinators named after drag queens? A new genus of soldier flies were discovered in Australia 2020 and given names that are indicative of their metallic and rainbow-colored bodies! Among Opaluma fabulosa, O. iridescens, O. opulens, O. sapphira and O. unicornis are O. rupaul, named after the drag queen RuPaul, and O. ednae, named after the Australian drag queen Dame Edna. 

Soldier flies belong to the Stratiomyidae family, which include many flower-visiting flies! Many adult soldier flies visit flowers for nectar and subsequently transfer pollen on their bodies as they travel from one bloom to the next. Six of these seven Opaluma species were impacted by the Australian bushfires in 2019 and 2020; their recent taxonomic identification will allow them to be monitored in recovery efforts following the fires. The full citation for these stunning soldier flies can be found here.


To stay on the theme of iridescence, next we will share some information about my (Jen’s) favorite pollinators: Orchid bees! Orchid bees are in the same family as bumblebees and honey bees (Apidae) but are found within their own tribe, Euglossini. Within Euglossini, there are only five genera: Algae, Euglossa, Eulaema, Eufriesa, and Exaraete. Only one species of orchid bee is found in the United States (Euglossa dilemma), with the majority being found in Central and South America.

Not all orchid bees are iridescent– bees from the genus Eulaema are the exception, which are more similar in appearance to bumblebees than they are to the metallic members of Euglossini. I find orchid bees to be mesmerizing, not only because of their novel color forms, but also their unique adaptations. Some orchid bees’ tongues (proboscises) are more than 1.5 times their body length in order to access nectar located in long, tubular flowers! These bees often fly with their proboscis tucked under their body, and it may look like a small tail as it trails past their abdomen.

Photo © sixlegs on iNaturalist,
all rights reserved.

Euglossa have highly modified tibias on their hind legs. Male members of Euglossa species have a “pouch” on their tibia, used to collect and store floral fragrances from flowers in the form of essential oils. These oils are later used to attract potential mates. I like to think Euglossine males would be excellent candle makers.


Mallory’s favorite pollinators are long-horned bees, in particular those from the genus Melissodes, which are highly abundant in the latter half of our field season! Mallory loves long-horned bees because they have many traits that make them easily identifiable in the field. Males have elongated antennal segments which are indicative of their common name ‘long-horned’. They often have interesting colored eyes as well- some of the specimens we collect have green, blue or grayish eyes that contrast greatly with their often blond-colored hair (scopa). Her favorite trait, however, is the scopa on their hind legs. When full of pollen, long-horned females often look like they have ‘pollen pants’ on, in contrast to the neat and tidy pollen baskets seen on bumblebees! Svea thinks their pollen pants make long-horned bees look like they’re wearing a pair of western-style chaps. Melissodes primarily pollinate species from the Asteraceae, with specialization occurring on asters, daisies, and sunflowers. Sometimes Melissodes are called ‘sunflower bees’.

Melissodes sp. visiting a cosmo, photo by Mallory Mead.

Photo © armadillocommander on iNaturalist, some rights reserved (CC BY-NC).

Svea’s favorite pollinator is Anna’s hummingbird (Calpyte anna). C. anna is one of seven hummingbird species native to Oregon. Svea enjoys watching Anna’s hummingbird as a pastime at her parents’ house: they have a small, active community of hummingbirds that are very vocal and can be seen fighting over their nectar sources (including their butterfly bush and hummingbird feeder).

Svea also mentioned that the males are particularly pretty, though it requires a particular angle of light to make their iridescent copper-red colored throats glow. The ‘Anna’ in Anna’s hummingbird comes from the French Duchess of Rivoli, Anna Masséna, who was part of the court of France’s last empress (Eugénie de Montijo, 1853-1870). Anna’s hummingbirds are important pollinators in California, where they feed from coastal chaparral flora that share a similar phenology (breeding and feeding patterns) with the pollinator.


Nicole is another member of the lab whose favorite pollinator is a hummingbird! Nicole’s favorite pollinator is the Rufous hummingbird Selasphorus rufus. The USDA Forest Service describes the Rufous hummingbird as “small but feisty long-distance migrant[s]”. They are small in size and feisty in their protection of their feeding territories, they have been known to chase off other hummingbirds, large insects, and even people! Some of their preferred host plants include morning glory (Ipomoea arborescens), ocotillo (Foquieria spp.), shrimp plant (Justicia spp.) and red-colored blooms from the mint family, such as Salvia elegans and Stachys coccinea. Nicole loves the Rufous hummingbird because she regularly saw them while she was growing up. They could regularly be seen foraging and defending their territory in her parent’s yard.

Photo © Wendy Feltham (wendy5 on iNaturalist), all rights reserved.

Cara’s favorite pollinator is the Western Tiger Swallowtail Papilio rutulus. This magnificent butterfly can be commonly found at Cara’s research plantings of butterfly bush (Buddleja spp.), and can also be spotted basking on yarrow or slowly fluttering along the hedgerows at Oak Creek Center for Urban Horticulture. Despite the name ‘butterfly bush’, Cara has found butterflies to be infrequent visitors of Buddleja, though of the few butterfly visitors they receive, the Western Tiger Swallowtail is the most common. Cara additionally grew up seeing swallowtails every summer, which is why they are her favorite pollinator! To read more about this swallowtail, check out Lucas’s Pollinator of the Week Post.

Photo by Cara Still

Let us know who your favorite pollinators are!

No Mow May

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.

My parents and I at my graduation

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 2020, a study in Appleton, Wisconsin found that yards that went unmown in the month of May had more diverse flora, more abundant flora, 3x greater bee species richness (total number of species), and 5x greater bee abundance than regularly mown green spaces. Though the results of this study cannot entirely be attributed to No Mow May, it does highlight the potential for areas traditionally covered in lawn to be used as spaces for pollinator conservation.

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.

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.

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

What we’re looking forward to planting this year

The growing season is quickly approaching, so I reached out to the members of the Garden Ecology Lab to ask them to share three plants they’re looking forward to growing this year.

LeAnn

Zowie™! Yellow Flame. Photo Courtesy of Johnny Seeds

 I love zinnias so much. This year I want to branch out and grow some less usual ones. Like those in the Queen Lime series and Zowie™! Yellow Flame. 

This isn’t a plant as much as a technique: I really want to maximize vertical space, and grow tomatoes and squash vertically. I’m going the route of C-Bite stake clips, self described as “tinker toys for the garden.” I can attach and snap to common garden stakes and build my own structures. Up, up and away! 

After watching all of the success in the Grow This! challenge last year with potatoes in grow bags, I’m inspired to grow potatoes for the first time. Really excited about this. And remember: the time to plant potatoes is St. Patrick’s Day. 


Tyler

The three veggies I am most looking forward to growing this season are tomatoes, peppers, and lettuce. Last season we grew over ten varieties of hot peppers and tomatoes in our hüglekultur beds. These types of beds are great for warm season plants that need just the right soil temperature. I am also looking forward to growing lettuce again next season because I eat so much salad! I got these amazing varieties of lettuce from Wild Garden seeds in Corvallis that I am super excited to try next year. To save space, I like to grow lettuce in a tower. I used chicken wire fencing, plant debris, and potting soil to create the foundation. I then used a stick to poke holes and plant the seeds. It grew into a beautiful ball of lettuce and I am so excited to try it again!


In addition to veggies, my goal for my outdoor space has always been to maximize the amount of flowers and wild space, while also reducing the amount of turf grass. During the winter, our garden looks a little unsightly with all the tarps and cardboard we use to smother the grass and weeds. In the spring, we remove the tarps and broadcast seeds all over the yard. My goal is to provide pollinators with year round foraging and improve the biodiversity on our property. One of our big projects last year was making a sunflower room in the yard. We planted American Giant sunflowers in a circle that eventually became a beautiful area for our community to hang out, surrounded by flowers and pollinators.


Jen

Elliot & I don’t have a yard to garden in so we’ve been experimenting with container gardening and a tiered planter box. The only place we can put them is on the north-facing side of our townhouse, which receives direct sunlight for a maximum two hours during the height of summer, so you can imagine our options are limited!

This year I am excited to stop experimenting and just grow some plants that have been successful: strawberries, basil, nasturtium. Although these are fairly basic selections, they have proven to produce in abundance in our tiny space! ( Abundant compared to squash and tomatoes that grow, take up a ton of space, and then get powdery mildew and die before a harvest is even possible).


Mykl

  1. Marigolds. I’m inspired to make a flower one of my goals this years as well. The timing for some summer and especially fall crops for me has been hard as I usually move in the middle of summer. One way or another, I expect to have a place to grow something over this period, and some of it will hopefully be beds of Marigolds.
  2. Napa cabbage, cuz I need to make kimchi again and stop buying it.
  3. Sweet potatoes, cuz I think I can do it again this year. And hey, when you strike it big, you gotta try again.

Nicole

I don’t have a garden to grow in here in Corvallis, but I do have an apartment… with a north-facing balcony. While the conditions aren’t ideal, I do plan to grow a few things in small containers this year.

1) Begonias! I grew them last year, and since they thrive in the shade, I had great success. They provided such a nice pop of color to the balcony and I loved sitting out there in the morning. Plus, you can get so many different colors that even if I have multiple pots they can all bring their own fun.

2) Chard. I haven’t tried this one before… but even if the crop I grow isn’t quite enough to make a meal out of, I love chard because it’s beautiful to look at. Plus, it’s one of the few crops that might make a go of it in the shade. 

3) Fiddle leaf. While I can’t eat this one either, I’ve been growing a fiddle leaf since I moved into my apartment. It lives inside with me during the winter and goes back outside during the summer. It’s easy to take care of, grows relatively quickly, and I love the way the big leaves can add texture and some height to a small gardening space.


Mallory

Last June, I moved into a rental house that has a small, mostly-shaded garden bed in the backyard. I’ve helped out my parents around the garden throughout my childhood, but this is the first garden I can call my own! Last summer I worked on bringing some life into the soil (which was incredibly compacted and muted grayish-brown in color) by growing a cover crop of buckwheat that flowered and brought some bees and syrphid flies to the yard. I then tilled in the “green manure” which attracted worms, millipedes and molds into the soil! Hopefully this will pay off in the Spring, as I’ve seeded a mixture of native and nonnative wildflowers from pollinator seed mixes.

As an undergraduate student studying horticulture I am both thrifty and surrounded by opportunities to acquire plants for free! I am enrolled in a plant propagation course this Winter and will have many seedlings coming my way to plant in the Spring, and through my involvement at the Oak Creek Center for Urban Horticulture, I generally grow whatever comes my way from the rejects, cuttings and leftovers from the greenhouses there.

If the flower seeds don’t pan out, I hope to grow some of my favorite herbs: Rosemary, Thai Basil and Cilantro!

A green sweat bee visiting a Cosmo, photographed by Mallory last summer

Cara

1.     Prospera basil- this is a disease resistant Italian type basil that simply makes life easier in the pacific northwest!  The downy mildew resistance actually comes from a thai basil parent, though I can’t detect that in the flavor profile much.  Planting this, I can rest assured my basil crop won’t be destroyed by wet weather late spring. 

2.     Japanese trifele black tomato- My favorite heirloom tomato.  This tomato is indeterminate, and has a complex flavor profile that usually comes with black tomato varieties, as well as a silky-smooth texture.  It is wonderful for fresh eating and canning alike!  I like to train my indeterminate tomatoes to a simple trellis constructed of fence posts, electrical conduit pipe, and twine. 

3. Heliotropes- I always purchase a few heliotropes for my patio.  The smell is intoxicating and I love their old fashioned charm.  This is the first year I am planning on starting them from seed.


Signe

Most of my planning for this year has more to do with long-term restructuring than individual plants, but I do have a new bed of Tristar day neutral strawberries I was able to put in last fall. I’m hoping for a much extended strawberry season by adding those to the June bearers.
I am encouraging more natives to spread and self-sow along the front of my property, where I put in a dry streambed a couple of years ago to catch a neighboring spring before it goes down the street. This has worked very well to provide groundwater into the summer.

I’ll be continuing the attempt to eradicate a bed of one native, Asclepias speciosa, which got away from me even though I knew it would be a spreader and was watching it. (Anyone want any? NOT recommended for small spaces). I’ve been collecting Carex, both native and non, to evaluate which are best for gardens here (durable, non-running, attractive year-round).
In my vegetable garden, I will NOT be growing potatoes this year. Last year’s large crop was riddled with wireworm, so I want to give the beds a rest. I may just grow summer cover crops, and grains that can serve that purpose, except for tomatoes, which I always grow a few of.


Charlotte

I’m excited to grow moringa again. Moringa is a superfood, very nutrient dense, and I think the foliage is quite aesthetically pleasing. Moringa prefer warmer weather, so the plants will grow all summer and then go dormant for the fall/winter. We planted the moringa in containers so we can move them around seasonally without disturbing the roots. We have a few dormant moringa plants hanging out in the greenhouses at Oak Creek Center for Urban Horticulture that are waiting for the return of sunny weather.

Everyone at the ILC Garden is excited to grow Lagos Spinach (Celosia argentea) again. Lagos Spinach (also called Nigerian Spinach, or Efo Shoko) is in the Amaranth family and has beautiful reddish-purple leaves with a bitter taste that really adds to the flavor profile of salads, soups & stir-fries.

Lagos spinach is not quite as bitter as some of the other amaranth leaves I’ve tasted before. As you might deduce from the name, the plant is indigenous to West Africa, but they seemed to be well adapted to the soils and climate of the Willamette Valley summer. Very heat and drought tolerant!!! The plant flowers later in the season, which is an added bonus for pollinators. The lagos spinach was such a lovely addition to the garden last summer… I’ve included a picture, the Lagos spinach is nestled between the collards and sunflowers in the photo.

I also plan to try growing more watermelon this year. We only planted two watermelon plants at the ILC Garden last year, and they did not fair well. We transplanted them a bit late, so I don’t think they had enough time to reach maturity. This year I’m dedicating about 150 sqft under the high tunnel for growing watermelon!


Svea

I don’t have any plans for planting this spring, as there is very little outdoor space at my house in Corvallis, and the indoor space is currently dominated by my twin brother’s many, many succulents, and his newly indoor orange tree. But at my family’s farm, my mom has endeavored these past few pandemic years to bring back her pre-children garden that she loved to work in.

This spring she is planning on planting some different types of tomato plants, as we are a tomato loving family. She also loves to plant sunflowers every year, and we have a measuring contest on which one gets the tallest. I think this year she is going to try her hand at growing different types of peppers and squash. I know she is very excited, and loves to try to to grow many different things, so if anyone has any suggestions, she would love to hear them.


In terms of growing food for the animals, the goats love to eat any (safe) leftovers, or any overripe harvests. Anything they don’t like, the pigs are more than happy to clean up! So we don’t grow anything specific, but some favorites are sunflower seeds for the goats, and potatoes for the pigs. Included here is our goat Nutmeg and her babies from last summer, waiting for some treats! 


Gwynne

We don’t have a vegetable garden going yet, but last year we had an amazing cover crop mix for the  paddocks that were “renovated” by our pigs. The mix included amaranth, field peas, squash, sunflowers, chia, sesame, millet, sorghum, flax, a variety of cereal grains, and other things that I couldn’t identify. It was certainly the most unusual pasture forage that I’ve seen, but our cows and sheep loved it!


Let us know what you’re looking forward to growing this year by commenting below!

Top 10 Oregon Native Plants for Pollinators: WEEK 10!!

The Garden Ecology Lab’s Pollinator Plant PR Campaign Presents….. Douglas Aster!

The Garden Ecology Lab is releasing a series of plant profiles of the top 10 Oregon native plants for pollinators, based on Aaron Anderson’s 2017-2019 field trials of 23 Oregon native plants. We will feature one plant per week for 10 weeks, this is week 10, which marks the end of our 10-week series! Profiles will include photos, planting information, and will highlight common pollinators of each plant.

Melissodes visits Douglas Aster. Photo by Tyler Spofford.

Plant Facts

  • Scientific Name: Symphyotrichum subspicatum
  • Life Cycle: Perennial
  • Growth Habit: Vigorous spreader, spreads through underground rhizomes
  • Bloom Duration: July-November
  • Hardiness Zone: 6-9
  • Special Traits: Drought tolerant, deer resistant
  • When to plant: Starts can be planted in the spring or early fall.

Pollinator Facts

  • Douglas aster provides both nectar and pollen to its insect visitors.
  • Aaron’s research found three species of long-horned bees (Melissodes robustior, M. lupinus, and M. microstictus) and three species of bees from the family Halictidae (Halictus ligatus, Agapostemon texanus angelicus and A. virescens) to be associated with Douglas aster.
  • Other common visitors to Douglas aster include syrphid flies and northern checkerspot butterflies! Douglas aster may also be a larval host to 8 different month species1.
Photo by © mandamasprime, some rights reserved (CC-BY-NC).

Douglas Aster‘s Native Range in Oregon

Douglas aster is native to Northwestern Oregon and most of the coast.

Maps and legend acquired from the Oregon Flora Project, with Imagery Sourced from Google. Copyright 2022© TerraMetrics

Douglas Aster as a pollinator plant

Douglas aster is native to Western North American with a range extending from Alaska to California. It has an impressive ability to spread and a high volume of flowers that buzz with pollinator activity throughout its long bloom season. Hosting a high abundance and diversity of bee visitors, Douglas aster is a pollinator plant superstar. It is particularly valuable as a late-season pollinator plant, able to provide both nectar and pollen to its visitors when these resources may otherwise be scarce in the landscape.

People often have strong reactions towards Douglas Aster – they either love it, or find it to be “weedy” in appearance. We hope that this highlight may help some people change their opinions about it! We in the Garden Ecology Lab love Douglas Aster for its abundant blooms in varying shades of purple and for its great capacity for supporting wildlife. In the late summer, we love watching the diversity of pollinators bouncing from one flower to the next! Some common visitors to Douglas Aster that we see at Oak Creek Center for Urban Horticulture include bumblebees, green bees, long-horned bees, small sweat bees, and butterflies, including the woodland skipper (pictured below) and the occasional grey hairstreak (Strymon melinus).

Here, we see a woodland skipper (Ochlodes sylvanoides) foraging from Douglas Aster!
Infographics developed by LeAnn Locher, Aaron Anderson, and Gail Langellotto.

Did you know?

By mid to late summer, Douglas aster is quite the frenzied pollinator feeding ground, making the Oak Creek team’s sampling effort always a bit of a challenge. These photos are from 2 years after these plants were established, so you can see just how full these young plants can get when grown in favorable conditions!

At Oak Creek, we started all of our Douglas Aster plots with 4x 4″ pots, planted in the spring of 2020. As you can see in the photos below, they easily filled up their 1×1 meter beds! If you’re worried about Douglas Aster taking over your garden, consider starting with a single plant and observe it over the season to see how it reacts to your garden environment. Aggressive spreaders can be used to fill spaces such as borders with forest edges or along fences where low maintenance plants are key. If you want to contain your asters, consider planting some in a large pot or in an area where you can easily control the spread of their underground rhizomes. The purple flowers contrast beautifully with other late season natives, such as goldenrod and Madia.

Jen standing next to her Douglas Aster experimental plots. Photo by Tyler Spofford.
Tyler vacuum sampling bees off of a Douglas Aster plot. Photo by Jen Hayes.

Photos from the field

Thanks for tuning in to the last posting of our Pollinator Plant PR Campaign! We hope you try growing some of these fantastic pollinators plants.

Top 10 Oregon Native Plants for Pollinators: Week 8

The Garden Ecology Lab’s Pollinator Plant PR Campaign Presents….. Globe Gilia!

The Garden Ecology Lab is releasing a series of plant profiles of the top 10 Oregon native plants for pollinators, based on Aaron Anderson’s 2017-2019 field trials of 23 Oregon native plants. We will feature one plant per week for 10 weeks, this is week 8! Profiles will include photos, planting information, and will highlight common pollinators of each plant.

Photo by iNaturalist user © slewiiis,
 some rights reserved

Plant Facts

  • Scientific Name: Gilia capitata
  • Life Cycle: Annual
  • Growth Habit: Erect, clusters
  • Bloom Duration: May – June
  • Hardiness Zone: 7-10
  • Light requirements: full sun
  • Special Traits: Drought tolerant, tolerant to various soil types.
  • When to plant: Seeds can be sewn directly in the fall, or can be stratified indoors over the winter before planting out in the spring.

Pollinator Facts

  • Globe Gilia provides both nectar and pollen to its insect visitors.
  • Gilia was found to be associated with the yellow-faced bumble bee, Bombus vosnesenskii in Aaron’s research.
  • Globe Gilia is also a larval host for at least one moth species, Adela singulella, but possibly four others as well.
  • In addition to insect visitors, Gilia is can be an occasional nectar source for hummingbirds1, which love its tubular flowers!

Photo by iNaturalist user © mudcitymelissa,
 some rights reserved

Globe Gilia‘s Native Range in Oregon

There are three subspecies of Gilia capitata in Oregon: Bluefield Gilia (ssp. capitata), Dune Gilia (ssp. chamissonis), and Pacific Gilia (ssp. pacifica). Dune Gilia and Pacific Gilia are considered to be rare plants in California (rare, threated, or endangered, rank 1B).

Distribution maps acquired from Oregon Flora with imagery from Google. Copyright 2022.

Globe Gilia as a pollinator plant

Globe Gilia may have only been associated with a single bee species in Aaron’s native plant research, but it is truly a powerhouse of an annual plant: it supports a highly diverse and abundant community of native bees! Gilia’s globe of flower heads provide pollinators with plenty of foraging spots to choose from, and the dense mass also allows easy access for both small and large pollinators, by acting as a nice landing pad. From their comfortable perch, butterflies and larger-bodied bees can dip their proboscis (tongue) into the nectar-rich blossoms. Smaller bees may need to crawl in to the individual flowers to access the nectaries.

Gilia is a great annual plant option to include in pollinator mixes and in meadows. It’s an easy to care for plant, requiring minimal water during the growing season. It grows up to three feet in height with lovely lavender – dark purple – blue flower heads, lacy foliage, and surprising blue pollen! The flowers contrast wonderfully with many other mid-summer blooms, such as poppies, Oregon sunshine, asters, and Clarkia.


Infographics developed by LeAnn Locher, Aaron Anderson, and Gail Langellotto.

Abundance Calculations. Bee abundance was calculated using estimated marginal means of bee visitation to each of our study plants from 5-minute observations conducted from Aaron’s 2017-2019 field seasons. Estimated marginal means (EM Means) were assigned to categorical values and averaged across years to yield the following categories: 0% = Very Low =EM mean below 0.49; 25% = Low = EM mean of 0.50 to 0.99; 50% = Moderate = EM mean of 1 to 1.49; 75% = High = EM mean of 1.50 to 1.99; and 100% = Very high = EM mean above 2.0.

Diversity Calculations. Bee diversity was based on the total sum of species collected on each of our study plants from 2017 to 2019. A Chao 2 Estimator was used to estimate total expected species richness for each plant; Chao 2 estimates were then used to create categorical values, as follows: 0% = Very Low = 9.99 or lower; 25% = Low = 10 to 14.99; 50% = Moderate = 15 to 19.99; 75% = High = 20 to 24.99; 100% = Very high = 25 or higher.


Did you know?

When you think about pollen, one color tends to come to mind: yellow. Perhaps you conjure up an image of a bumblebee in a field of clover, weighed down by some giant orange-toned pollen baskets as well. Many of us might stop there, and conclude that pollen must be either yellow or orange, as those are the predominant pollen colors we see in the plant world. The absolutely exciting news is that, like flower colors, pollen also comes in a rainbow of colors. Globe Gilia, for example, has pollen that comes in shades of blue!

A spotlight on pollen colors

As some of you may remember from my (Jen’s) 2021 field update, last summer, a few of us from the Garden Ecology lab had the wonderful opportunity to visit Jasna Guy and Lincoln Best’s exhibit ‘In Time’s Humm’ at the High Desert Museum in Bend. Part of this display was a pollen color study, showing Jasna’s recreations of pollen colors using pastels. We saw pollen in shades of yellows, oranges, red, pink, purple, white, and even green. Color can truly be found anywhere if you look closely enough! Perhaps it should be no surprise then, that even nectar may come in various colors, too… If you’re excited about pollen colors like we are, you might see if your local library has a copy of this book, and you might enjoy looking at pollen colors through the seasons, put together by the North Shropshire Beekeepers’ Association.

Now back to Globe Gilia: Photos from the field

Tune in next week for the next edition of our Pollinator Plant PR Campaign.

Top 10 Oregon Native Plants for Pollinators: Week 6

The Garden Ecology Lab’s Pollinator Plant PR Campaign Presents….. Common Madia (AKA Tarweed)!

The Garden Ecology Lab is releasing a series of plant profiles of the top 10 Oregon native plants for pollinators, based on Aaron Anderson’s 2017-2019 field trials of 23 Oregon native plants. We will feature one plant per week for 10 weeks, this is week 6! Profiles will include photos, planting information, and will highlight common pollinators of each plant.

Photo © Rob Irwin
 some rights reserved

Plant Facts

  • Scientific Name: Madia elegans
  • Life Cycle: Annual
  • Growth Habit: Erect, slender
  • Bloom Duration: July – September
  • Hardiness Zone: 1-11
  • Light requirements: Prefers full sun, will tolerate partial shade.
  • Special Traits: Drought tolerant, deer resistant, seeds valued by birds, adaptable to many soil types and textures.
  • When to plant: Seeds can be sown directly in the fall, or sown in containers or cold frames in the winter. Stratify seeds if growing indoors.

Pollinator Facts

  • Common madia provides both nectar and pollen to its insect visitors and blooms during a period where foraging resources are often scarce (late summer – early fall).
  • Madia was found to be associated with two bee species in Aaron’s research: the Bi-colored Sweat Bee (Agapostemon virescens) and Titus’s Sweat Bee (Lasioglossum titusi)
  • Madia is also the larval host for three moth species: the Spotted Straw Sun Moth (Heliothis phloxiphada), the Small Heliothodes Moth (Heliothodes diminutivus), and an Epiblema moth (Epiblema deverrae)1.

Photo © Chris Cameron
 some rights reserved

Common Madia‘s Native Range in Oregon

Madia elegans is native to most of Western Oregon. Although it's native range does not extend east of the Cascades, it is a hardy annual that may do well in Central- and Eastern- Oregon gardens.

Map acquired from Oregon Flora with imagery sourced from Google.

Common Madia as a pollinator plant

Common Madia is an ideal plant for pollinator gardens due to its long bloom duration and attractiveness to bees, caterpillars, and butterflies. Madia was found to attract both a high abundance and a high diversity of bee visitors, which further speaks to its use as a great pollinator plant! Due to it’s late-summer bloom period, Madia can act as a great source of forage for it’s various visitors when there may not be many other plants flowering in the landscape. Madia flowers, which close at dusk and reopen in the morning, may also come with a fun surprise if you catch them before the sun has finished its ascent: if you’re lucky, you may be able to find male long-horned-bees sleeping in groups within the flowers2.


Infographics developed by LeAnn Locher, Aaron Anderson, and Gail Langellotto.

Abundance Calculations. Bee abundance was calculated using estimated marginal means of bee visitation to each of our study plants from 5-minute observations conducted from Aaron’s 2017-2019 field seasons. Estimated marginal means (EM Means) were assigned to categorical values and averaged across years to yield the following categories: 0% = Very Low =EM mean below 0.49; 25% = Low = EM mean of 0.50 to 0.99; 50% = Moderate = EM mean of 1 to 1.49; 75% = High = EM mean of 1.50 to 1.99; and 100% = Very high = EM mean above 2.0.

Diversity Calculations. Bee diversity was based on the total sum of species collected on each of our study plants from 2017 to 2019. A Chao 2 Estimator was used to estimate total expected species richness for each plant; Chao 2 estimates were then used to create categorical values, as follows: 0% = Very Low = 9.99 or lower; 25% = Low = 10 to 14.99; 50% = Moderate = 15 to 19.99; 75% = High = 20 to 24.99; 100% = Very high = 25 or higher.


A syrphid fly visiting a Madia flower. Photo by Signe Danler.

Did you know?

The other common name for Madia, “Tarweed”, comes from its foliage. It’s covered in stiff trichomes (hairs) and stalked glands which emit a tar-like scent. Common Madia is not the only species with this nickname, it applies to plants in the entire genus! For example, Madia glomerata, “Mountain Tarplant”, is a species of Madia native to the Northeast United States.

Common Madia‘s fruits are flattened achenes, which are valued by small mammals and birds as a food source. The achenes were also used by Indigenous groups, including the Pomo, Miwok, and Hupa and as a staple food source3. The fruits were often roasted with hot coals and then ground into flour.

Photos from the field

Tune in next week for the next edition of our Pollinator Plant PR Campaign.

Top 10 Oregon Native Plants for Pollinators: Week 4

The Garden Ecology Lab’s Pollinator Plant PR Campaign Presents….. Varileaf Phacelia!

The Garden Ecology Lab is releasing a series of plant profiles of the top 10 Oregon native plants for pollinators, based on Aaron Anderson’s 2017-2019 field trials of 23 Oregon native plants. We will feature one plant per week for 10 weeks, this is week 4! Profiles will include photos, planting information, and will highlight common pollinators of each plant.

Photo by iNaturalist user Leslie Flint.
CC Some rights reserved.

Plant Facts

  • Scientific Name: Phacelia heterophylla
  • Life Cycle: Biennial/ annual, typically grown as an annual in Oregon
  • Growth Habit: Upright, mounding
  • Bloom Duration: April – July
  • Hardiness Zone: 3-7
  • Special Traits: Shade tolerant, drought tolerant
  • Light requirements: Full sun to part shade
  • When to plant: Seeds should be sown in the fall, starts may be planted in the fall or spring after the last chance of frost.

Pollinator Facts

  • Varileaf Phacelia provides both nectar and pollen to its insect visitors.
  • Phacelia was found to be associated with five bee species in Aaron’s research: the obscure bumblebee (Bombus caliginosus), Edward’s long-horned bee (Eucera edwardsii), the fuzzy-horned bumblebee (Bombus mixtus), the confluent miner bee (Panurginus atriceps), and the yellow-faced bumblebee (Bombus vosnesenskii).
  • Phacelia is also a larval host for 4 moths: the Bilobed Looper Moth (Megalographa biloba), the Geranium Plume Moth (Amblyptilia pica), the Orange Tortrix Moth (Argyrotaenia franciscana) and Clepsis fucana1.

Photo by Aaron Anderson

Varileaf Phacelia‘s Native Range in Oregon

Phacelia heterophylla is native to most of the Western United States – From Washington to California, east to Montana and south to New Mexico. It is additionally native to Canada, where it is currently considered “imperiled” by the IUCN red list2.

Varileaf Phacelia's native range covers nearly the entire state of Oregon! It's native habitat includes moist conifer forests, riparian areas, sagebrush, mountain brush, as well as in aspen and fir communities3.
Maps and legend acquired from the Oregon Flora Project, with Imagery Sourced from Google.

Varileaf Phacelia as a pollinator plant

A female long-horned bee (Eucera sp.) searches for some leftover forage on a spent Phacelia heterophylla inflorescence. Photo by Aaron Anderson.

Varileaf Phacelia is the epitome of an underappreciated pollinator plant! This annual with petite white flowers attracts both an abundance and diversity of insect visitors. With stamen that stick out of the corolla, it heavily advertises its nutritious rewards, attracting plenty of busy bees. In fact, it commonly hosted 5 different bee species in Aaron’s field surveys, including three charismatic bumblebee species, one of which is currently listed as “vulnerable” on the IUCN Red List: Bombus caliginosus, the obscure bumblebee4.


Infographics developed by LeAnn Locher, Aaron Anderson, and Gail Langellotto.

Abundance and Diversity Calculations. Bee abundance was calculated using estimated marginal means of bee visitation to each of our study plants from 5-minute observations conducted from Aaron’s 2017-2019 field seasons. Estimated marginal means (EM Means) were assigned to categorical values and averaged across years to yield the following categories: 0% = Very Low =EM mean below 0.49; 25% = Low = EM mean of 0.50 to 0.99; 50% = Moderate = EM mean of 1 to 1.49; 75% = High = EM mean of 1.50 to 1.99; and 100% = Very high = EM mean above 2.0.

Bee diversity was based on the total sum of species collected on each of our study plants from 2017 to 2019. A Chao 2 Estimator was used to estimate total expected species richness for each plant; Chao 2 estimates were then used to create categorical values, as follows: 0% = Very Low = 9.99 or lower; 25% = Low = 10 to 14.99; 50% = Moderate = 15 to 19.99; 75% = High = 20 to 24.99; 100% = Very high = 25 or higher.


In a survey of gardeners conducted by Aaron and the Garden Ecology Lab, Phacelia heterophylla ranked last among 23 native plants scored for their aesthetic appeal. It may appear “weedy” to some gardeners, but as an annual, it could easily be interspersed with more attractive annual face flowers (such as California poppy, meadowfoam, farewell to spring, or baby blue eyes) to create a colorful and nutritious pollinator garden. Varileaf Phacelia is also a great native annual to include in dryland pollinator gardens, considering it is drought tolerant and able to grow in both nutrient poor and rocky soils.

Did you know?

Photo by iNaturalist user jwlipe. CC Some rights reserved.

Varileaf Phacelia also has the common name "Variegate Scorpionweed", and the pictures above can show you exactly why! It's flowers are borne on elongated stems which are tightly curled, similar to a fiddlehead from a fern! The flowers bloom from the base to the apex of the stem, and the "scorpion tail" slowly unravels as the blooms travel up the stem.

Photos from the field

Of all of the plants we highlight in this 10-week series, Varileaf Phacelia is the one plant that Gail regularly says is in great need of it's own public relations (PR) team. The goal of these plant profiles is to share information and photos of these plants that might convince readers to love this plant as much as we (and the bees) do! 

Let us know which plants have caught your eye, or those that may still take some convincing, by leaving a comment below! 🐝

Tune in next week for the next edition of our Pollinator Plant PR Campaign.

Top 10 Oregon Native Plants for Pollinators: Week 2

The Garden Ecology Lab’s Pollinator Plant PR Campaign Presents….. Oregon Sunshine! ☀️

The Garden Ecology Lab is releasing a series of plant profiles of the top 10 Oregon native plants for pollinators, based on Aaron Anderson’s 2017-2019 field trials of 23 Oregon native plants. We will feature one plant per week for 10 weeks, this is week 2! Profiles will include photos, planting information, and will highlight common pollinators of each plant.

Plant Facts

  • Scientific Name: Eriophyllum lanatum
  • Other names: Common woolly sunflower
  • Life Cycle: Perennial
  • Foliage: grey, woolly lobed leaves
  • Growth Habit: Upright, spreading, “shrubby”; typically 12-14″ in height, may need to be cut back if it becomes too leggy to maintain upright flowers.
  • Bloom Duration: June – September
  • Hardiness Zone: 5-10; can tolerate cold up to -15 F
  • Special Traits: Drought tolerant
  • When to plant: Starts can be planted in the spring or fall, seeds should be sown in the fall.

Pollinator Facts

  • Oregon Sunshine provides both nectar and pollen to its insect visitors.
  • Oregon Sunshine was found to be associated with one species of bee in Aaron’s research: Panurginus atriceps, the black-tipped miner bee.
  • Oregon sunshine is a host plant to 7 moths: the Gernaium Plume Moth, Orange Tortrix Moth, the Lupine Ghost Moth, and three moths without common names: Telethusia ovalis, Phalonidia latipunctata, and Phtheochroa aegrana.
  • Butterflies including orange sulfurs, red admirals, commas, and skippers are also often attracted to Oregon Sunshine.

Oregon Sunshine‘s Native Range in Oregon

Oregon Sunshine commonly grows on both sides of the Cascades as well as through Southern Washington and California, and has at least 6 different varieties present across the state of Oregon (slide 2).

Maps and legend acquired from the Oregon Flora Project, with Imagery Sourced from Google. Copyright 2021© TerraMetrics

Oregon Sunshine as a pollinator plant

Oregon Sunshine is a widespread perennial in the sunflower family (Asteraceae). It provides resources to a great diversity of pollinators, including bees, butterflies, moths, and caterpillars. This native sunflower is a great late summer nectar plant with wide yellow flowers (sometimes up to 2″ across) that allow pollinators easy access to their nectaries!

Infographics developed by LeAnn Locher, Aaron Anderson, and Gail Langellotto.
Abundance and Diversity Calculations. Bee abundance was calculated using estimated marginal means of bee visitation to each of our study plants from 5-minute observations conducted from Aaron's 2017-2019 field seasons. Estimated marginal means (EM Means) were assigned to categorical values and averaged across years to yield the following categories: 0% = Very Low =EM mean below 0.49; 25% = Low = EM mean of 0.50 to 0.99; 50% = Moderate = EM mean of 1 to 1.49; 75% = High = EM mean of 1.50 to 1.99; and 100% = Very high = EM mean above 2.0.

Bee diversity was based on the total sum of species collected on each of our study plants from 2017 to 2019. A Chao 2 Estimator was used to estimate total expected species richness for each plant; Chao 2 estimates were then used to create categorical values, as follows: 0%  = Very Low = 9.99 or lower; 25% = Low = 10 to 14.99; 50% = Moderate = 15 to 19.99; 75% = High = 20 to 24.99; 100% = Very high = 25 or higher.

Did you know?

The white-grey trichomes (the little hairs on the stems and leaves) add a lovely color to gardens and also act as an important adaptation for this drought-tolerant plant. The trichomes help Oregon Sunshine conserve water by both reflecting heat and reducing the amount of air that moves across a leaf’s surface. Though this trait helps Oregon Sunshine endure intense, dry landscapes, it can also explain why it might not do well in the gardens of those with a tendency to “kill with kindness”… this plant does not want a lot of water! It should be watered no more than once a month once established, so over-waterers beware!

Photos from the field

Tune in next week for the next edition of our Pollinator Plant PR Campaign.

2021 Field Update: Natives & Nativars

Our second field season studying pollinator visitation to Oregon native plants and native cultivars spanned from April to late September of 2021, although if Douglas Aster had any say in the matter, we would likely still be sampling. The densely blooming Symphyotrichum subspicatum continued to produce a smattering of new flowers through November of last year, and we predict it will do the same this year, too!

Our field crew this summer included Tyler, Svea, Mallory and I. Together, we sampled on 33 different dates across the growing season, allowing us to collect around 2000 physical pollinator specimens, and observe 6,225 unique interactions between pollinators and our study plants! This season we conducted floral trait measurements (including the dimensions of flowers), took multispectral photos, and additionally collected pollen from a subset of our study plants.

From left to right: Mallory vacuum-sampling off of Douglas Aster 'Sauvie Snow', Tyler shaking a farewell-to-spring flower to get pollen off of it, and Svea photographing Baby Blue Eyes 'Penny Black'.

This year, we introduced a third cultivar for California poppy (Eschscholzia californica ‘Purple Gleam’), yarrow (Achillea millefolium ‘Moonshine’), and farewell-to-spring (Clarkia amoena ‘Scarlet’). The new cultivars were established in the spring, which resulted in a late bloom for the annuals, so we expect to see them blooming during their typical period in 2022. The Achillea ‘Moonshine’ replaced Achillea ‘Salmon Beauty’ in being the most abundant yarrow cultivar; it began blooming almost immediately as it was planted into our field site and is still continuing to push out blooms through October alongside the Douglas Asters. 

The plant groups in our study: the larger circles with orange text are the native plants, and the smaller circles and turquoise text are the cultivars. The top row contain the perennials yarrow, western red columbine, great camas, and Douglas aster. The bottom row shows the three annuals farewell-to-spring, California poppy, and baby blue eyes.

In addition to watching new plants bloom in the study garden, we had the opportunity to observe many incredible pollinators in the field this summer. We saw a hummingbird visit the Western Red Columbine, we tried to capture videos of leaf-cutter bees snipping little petal pieces off of farewell-to-spring, and at a neighboring plot we observed a male wool-carder bee section off an entire patch of Salvia for a female bee.

On the left: Farewell-to-spring 'Scarlet' with crescents cut out of the petals by leafcutter bees. Top right: A female wool-carder bee (Anthidium manicatum) collecting trichomes from Yarrow 'Calistoga'. Middle right: A leafcutter bee with a piece of petal from Farewell-to-spring 'Dwarf White'. Bottom right: A leaf cutter bee removing a piece of petal from Farewell-to-spring 'Aurora'.

We were also able to take a couple educational field trips this field season in order to learn about pollinator studies ongoing outside of Oak Creek. In June, we went up to the North Willamette Research and Extension Center in Aurora, OR to listen to three talks about pollinators at the Blueberry Field Day. We learned how to score the productivity of honeybee hives, how to properly don a the top of a bee suit, about blueberry’s best pollinators, and blueberry research projects at the University of Washington.

In August, we made a trip to Bend for a different kind of study… an artistic one! We travelled to the High Desert Museum in order to visit Jasna Guy and Lincoln Best’s exhibit “In Time’s Hum…”. Jasna is a brilliant artist inspired by pollinators, which translates into the subject of her pieces as well as her artistic media. Many of her pieces are made using encaustic (a method of painting using wax, bee’s wax in her case!), dipped directly into bee’s wax, or involve pollinators in some other format, including her color study of pollen, which attempts to replicate the colors of fresh pollen as well as the colors after bees have mixed them with nectar. In the center of exhibit were two cases filled with bees collected and identified by Linc, surrounding some of the dried plant specimens they forage on.

These field trips were a wonderful way to see what other pollinator work is happening in our broader community and to inspire future studies. It was especially exciting to see how Jasna and Linc combined art and science with their exhibit, which is something many of us in the Garden Ecology Lab are interested in.

1. Mallory, Svea, and Jen at the blueberry Field Day. 2. Svea, Jen, Mallory, and Tyler at the High Desert Museum. 3. A panorama of the "... In Time's Hum ... " exhibit. 4-5. Art on the outside of the exhibit. 6. A snapshot of two pollen samples from Jasna Guy's pollen color study.

While we cannot make conclusions until we complete our final field season, we are excited to report some of the variation in visitation between native plants and native cultivars that we have observed in our first two field seasons. In the first field season, our observations of native bees foraging on the study plants revealed three plant groups to have variable amounts of visitation. Yarrow, farewell-to-spring, and California poppy all had at least one cultivar that received substantially less native bee visits than the native type. In our second year, all three of farewell-to-spring’s cultivars received less visitation than the native Clarkia amoena. Poppy had only one cultivar with less native bee activity than the native (Purple Gleam), and in the case of Douglas Aster, both of the cultivars actually had more visitation by native bees than the native. 

Figure 1: Average Abundance of Foraging Native Bees during 5-Min Observations in 2021. Individual plants are color-coded by genus. The naming scheme combines the first three letters of the genus and specific epithet; cultivars are denoted by an underscore and a 1-2 letter code to identify them. For example, AQUFOR is the native Aquilegia formosa, and AQUFOR_XT is Aquilegia  x ‘XeraTones’.

Spring with the Mason Bees

Written by Mallory Mead

My name is Mallory Mead, and I am new to the Garden Ecology Lab! I am an undergrad studying Horticulture and minoring in Entomology, and I started a few weeks ago as an assistant to Jen Hayes on her study of pollinator attraction to native plants and nativars.

I enrolled in Oregon State’s URSA Engage program, which gives undergrads a taste of research experience in the Winter and Spring of their first year, and joined a project studying how mason bees might be impacted by climate change with Dr. Jim Rivers of the department of Forest Ecosystems and Society. The study seeks to examine the effects of warming temperatures on mason bee behavior and the development of brood.

The Western US’s native species of mason bee, the Blue Orchard Bee (BOB) is known to be an excellent orchard pollinator. On many orchard crops they are more efficient at pollination than honey bees on a per individual basis, and so the commercial management of BOBs is being explored as honey bee colonies suffer management challenges and colony losses in recent years.

A mason bee nest within a reed. “DSC_0082” by tpjunier is licensed under CC BY 2.0.

Mason bees have a short lifespan of 4 to 6 weeks. Emerging in the early spring, males die shortly after mating, while females build nests in holes in wood or reeds. They forage for pollen and nectar to form provision masses in which they lay their eggs. They also collect mud to form partitions between each provision mass and to cap the nest once it is full. Their offspring will feed on the provisions and metamorphose into cocooned adults to overwinter in their cells and emerge the following spring.

To ensure the bees had ample nutrient resources, the project was conducted next to the organic cherry orchard at OSU’s Lewis Brown Farm. Before the cherries bloomed, 6 nest structures were designed and constructed by Jim, Ron Spendal (a mason bee house conisuerrier) and Aaron Moore of Revolution Robotics.

Nest structures, solar panels, and camcorders at Lewis Brown Farm.

Each structure has 3 shelves with 16 nest holes each, lined with paper straws so that the nests can be easily removed and examined. The structures are solar powered, and each shelf is heated to a different increment above the ambient temperature i.e. + 0°C , + 2°C, + 4°C, + 6°C, + 8°C, + 10 °C, and + 12°C. These differentials represent many potential warming outcomes of climate change.

Nest Structure Number 2 with labelled component parts. A. The Electronics control box. B. Cocoon-release box. C. Shelves sandwiched by heating pads, and lined with paper nesting straws

Our Hypotheses

  • We predicted that female mason bees will select the warmer nests first, and that females will leave nests earlier in the morning to begin foraging because they will reach the critical internal temperature necessary for flight sooner.
  • If heated bees have a greater window of foraging time, then we predict they’ll be able to construct nests at a faster rate in the warmer nests.
  • With greater nest construction will come a greater production of offspring from the bees in the warmed nests.

But…

  • In terms of offspring quality, we predict that offspring of heated nests will emerge as weak individuals and mortality will be the highest for the heated brood.

…and we are pretty confident about this last prediction.

Insects are poikilothermic meaning their internal temperatures are determined by the environment. Past studies by researchers Bosch and Kemp have reported that mason bees who are overwintered at warm temperatures will “use up their metabolic reserves and are likely to die during the winter”. And a more recent study by researchers at the University of Arizona found that mason bees subjected to heating resulted in reduced body mass, fat content and high mortality of the mason bee offspring.

Data Collection

One of the latest male mason bees to emerge, surrounded by empty cocoons in the release box.

Our mason bees started hatching from cocoons in mid-April and began to colonize the nest structures. I captured video footage of the bees as they emerged in the morning to forage. If bees from heated nest sites emerge earlier, this will support our hypotheses that they reach their critical-for-flight temperature earlier, and get a leg-up on foraging compared to their neighbors.

I also conducted “nest checks” to track the rate of nest construction along with two other research assistants.

In the fall, the nest tubes will be extracted to examine the reproductive output, and in the following spring, offspring will be assessed for rates of mortality, offspring mass, and fat content.

Obstacles

Some of the challenges along the way have included dealing with insect pests. Spiders were easygoing inhabitants of the nest straws, for they only nested in empty straws, so we’d swap them out for a clean one. The earwigs were much more pervasive, and went for the already inhabited nests. As generalist foragers, the earwigs took advantage of provision balls of nectar and pollen that had not yet been sealed off by mud. Once I read that earwigs will indeed eat the mason bee eggs that are laid into the provision masses, I knew it was crucial to remove the earwigs from all nests, but these feisty creatures proved determined to stay. We ordered some tanglefoot, a sticky substance to trap the earwigs on their way up the structure post, and meanwhile I coaxed earwigs out with tiny pieces of grass. Jabbing them repeatedly would eventually provoke them to charge at the blade of grass and fall out from the straw.

Yellowjackets were another opportunistic nester. They’d sneak into the cocoon boxes to build nests, and always gave me a start when opening the tiny boxes. I removed their nests with an extended grabber tool and would destroy them in any way I could. I feel immensely lucky not to have been stung through this process.

The most terrifying surprise during the project was a fat snake that was living in the solar panel battery box. It popped out at me hissing while I conducted a routine check. Alas, I was too spooked to take on this unexpected visitor and let it leave on its own time.

Preliminary Findings & Observations

By mid-May, a pretty clear pattern was emerging. At each structure, the control shelf’s nests (+ 0 °C) were full and capped with mud, while the hottest shelves were almost completely empty. We will analyze nest check data to confirm that these patterns are not just arising by chance, but a study that was released this past April showed another species of mason bee in Poland following the same pattern of nest site preference and selection for cooler nest sites.

The mason bees’ unexpected behavior of avoiding the heated chambers may lead to trouble during the second part of the experiment because this means our sample size for heated offspring has become so tiny, but here it is important to note that this is mason bee project is a pilot study and so the data collected this year will simply influence more specific future research.

these preliminary findings make me think that mason bees have an ingrained sense to avoid warm nests, which might show mason bees’ adaptability in the face of climate change, that is, if they can manage to continue finding cool nests. People managing mason bees find that nests facing the morning sun are the most attractive to the bees, but I wonder how long it will be before temperatures rise and mason bees start avoiding these sunny nests.

Moving Forward

By the end of May, I’d only see a few the mason bees per visit, so the season was clearly coming to an end. I wrapped up data collection and am now spending the summer extracting data from the video footage, and checking up on the bees to ensure they are safe and sound until Fall inspections.

I am wishing the best to both the wild bees in our region and those in our study, as the temperatures skyrocket this week but with this summer’s heat wave, I don’t think we need to simulate climate change; it is right here before us. Even though it is practically inevitable that temperatures will rise to dangerous heights in my generation’s lifetime, there is so much life to be saved, and there is no time to waste.

“Blue Orchard Bee, Osmia lignaria” by SeabrookeLeckie.com is licensed under CC BY-NC-ND 2.0″