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.  

Garden Ecology Lab, Fall 2017: (left to right) Signe Danler, Gail Langellotto, Lucas Costner, Isabella Messer, Michael Nelson, Aaron Anderson

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

We are soliciting Master Gardener feedback on the attractiveness of the native wildflowers that Aaron Anderson is studying for pollinator plantings. More detail on the study can be found at:

http://blogs.oregonstate.edu/gardenecologylab/native-plants-2/

As we mention, not only are we interested in finding plants that support ecosystem services; we also want to find plants that gardeners find attractive, and that they would want.

This is where you come in. If you are willing, please let us know which ones you would like to see in your own garden, based on their looks, alone. Below is the recruitment letter, with further information about participation. Thank you for your consideration!

 

Study: Screening Willamette Valley Wildflowers for attractiveness to Pollinators and Natural Enemies

Graduate Research Assistant: Aaron Anderson (andeaaro@oregonstate.edu; 503-860-9286)

Principal Investigator: Dr. Gail Langellotto (Gail.Langellotto@oregonstate.edu; 541-737-5175)

 

Dear Master Gardener,

 

You are invited to take part in a survey that will generate useful information on the ornamental value of pollinator-friendly native wildflowers.

 

Previous research has shown that urban greenspaces, notably gardens, can provide excellent habitat for pollinators and other invertebrates. The inclusion of pollinator-friendly plantings in gardens has the potential to improve habitat quality and connectivity in otherwise inhospitable landscapes. However, research on which Willamette Valley wildflowers are best to use for these plantings is lacking. Thus, I am conducting a research project to assess the relative attractiveness of 23 wildflower species native to the Willamette Valley (Oregon) to pollinators and natural enemies. Additionally, I would like to assess the aesthetic value of these plants to identify native flowers that are also attractive for ornamental use in home gardens.

 

As a Master Gardener, I am asking your help with my study, “Screening Willamette Valley Wildflowers for attractiveness to Pollinators and Natural Enemies”.  If you are aged 18 or older, and are currently a Master Gardener, or have been a Master Gardener in the past, I would appreciate it if you could take 10-15 minutes to respond to this survey:

 

http://bit.ly/OSUNative

 

Your survey responses will be recorded as a group. Thus, your response will be anonymous.  If the results of this survey are published, your identity will not be made public. The security and confidentiality of information collected from cannot be guaranteed.  Confidentiality will be kept to the extent permitted by the technology being used.  Information collected online can be intercepted, corrupted, lost, destroyed, arrive late or incomplete, or contain viruses.

 

Your participation in this study is voluntary and you may refuse to answer any questions(s) for any reason.  There are a limited number of Master Gardeners in Oregon, so your participation in this study is important. If you do not want to participate and do not wish to be contacted further, do not fill out the online questionnaire. There are no foreseeable risks to you as a participant in this project; nor are there any direct benefits. However, your participation is extremely valued.

 

If you have any questions about the survey, please contact me at 503-860-9286 or via email at andeaaro@oregonstate.edu.  If you have questions about your rights as a participant in this research project, please contact the Oregon State University Institutional Review Board (IRB) Human Protections Administrator at (541) 737-4933 or by email at IRB@oregonstate.edu.

 

Thank you for your help. I appreciate your consideration.

 

Sincerely,

Aaron Anderson

 

 

 

 

 

 

Our paper on the potential for bee movements between gardens and urban/peri-urban agriculture has been published in a special issue on Agroecology in the City, in the journal Sustainability.

Langellotto, G.A.; Melathopoulos, A.; Messer, I.; Anderson, A.; McClintock, N.; Costner, L. Garden Pollinators and the Potential for Ecosystem Service Flow to Urban and Peri-Urban Agriculture.Sustainability 2018, 10, 2047.

In this paper, we estimated how far the bees we collected from our Garden Pollinators Study could move between gardens and pollination-dependent cropland. We found that when pollination-dependent crops (commercial-scale or residential-scale) are nearby, 30–50% of the garden bee community could potentially provide pollination services to adjacent crops.

But, we currently know so little about bee movements in complex landscapes ~ if and how bees move across roads or through gardens embedded in housing developments. This question will be a focus of our future work.

Some of the bees collected from our 2017 Garden Pollinators study.
Western Columbine
California poppy
Oregon Iris

 

 

 

 

 

 

 

 

 

 

 

Over the past year, I have have given many presentations that highlighted the high bee activity at ‘site 51’; a garden that is fairly small (0.1 acre) and in a heavily developed area of East Portland. Despite its size and location, ‘site 51’ had the second highest number of bees from our 2017 collections. I suspect bee diversity will also be high at site 51.

This garden is managed by someone who is an avid Xerces Society member. He gardens specifically for pollinators, and it shows! His garden is a true testament to the idea that ‘if you plant it, they will come’.

So what plants are in this garden? Our preliminary plant list (from a brief 2017 survey) can be found below. I will add Latin names, when I have a moment. For now, I hope that the common name list might introduce you to a new plant or two that might work well in your own garden.

Several of the plants in this garden are native to the Willamette Valley, and are included in Aaron Anderson’s study of native plants. The photos in this post are from Aaron’s field research.

 

 

 

 

  • Iris
  • Nodding onion
  • Yarrow
  • Fescue
  • Milkweed
  • Woodland strawberry
  • Goldenrod
  • Phacelia
  • Borage
  • Douglas Aster
  • Lupine
  • Daisy
  • Mallow
  • Dogwood
  • California poppy
  • Columbine
  • Meadow foam
  • Yellow eyed grass
  • Cinquefoil
  • Blue eyed grass
  • Currant
  • Crabapple
  • Blue elderberry
  • Anise hyssop
  • Coreopsis
  • Spirea
  • Mock orange
  • Serviceberry
  • Trillium
  • Coneflower
  • Snowberry
  • Oregon grape
  • Shore pine
  • Maple
  • Pearly everlasting
  • Globe thistle

 

garden ecology lab

garden ecology lab

Urban agriculture has received a lot of attention over the past decade, as more folks are looking to localize their food supply, reduce food miles, and/or exert greater control over their food. Urban agriculture, however, brings a distinct set of challenges from farm systems in more rural regions. For example, urban farms tend to be relatively small and diverse (which can make it challenging to rotate crops), and are often close to neighborhoods and housing developments (which may make urban farms more prone to nuisance complaints). Urban farmers tend to be younger and to have less experience in agriculture, compared to rural farmers, and in need to high levels of technical assistance from Extension and other providers (Oberholtzer et al. 2014). However, many of the resources that Extension has to offer are focused on traditional growers, rather than new urban farmers.

Our lab group wanted to examine an issue that is specific to urban growers, and for which we could find very little information: urban agricultural soils. Soil scientists have prioritized research on urban agricultural soils as a key priority for the 21st century (Adewopo et al. 2014). Yet for his thesis work, Mykl Nelson could only find 17 academic papers that looked at urban agricultural soils in the United States. Most of these studies focused on

residential-scale or community-scale urban agriculture (in home or community gardens). Only one paper looked at soils on an urban farm.

Still, residential- and community-scale gardening is an important type of urban agriculture. In Portland, a conservative count of 3,000 home gardens collectively covers more than 20 acres of land (McClintock et al. 2013). In Chicago, residential food gardens cover 29 acres of land, and represent 89% of all urban agriculture (Taylor and Lovell 2012). In Madison, WI, more than 45,000 food gardens cover more than 121 acres of land (Smith et al. 2013).

For Mykl’s thesis, he looked at urban soils from 27 Master Gardener-tended gardens, in Portland and Corvallis, OR. Even though all gardens were tended by OSU Extension trained Master Gardeners, they were incredibly diverse: 74 different annual crops, and 58 different perennial crops were grown across these gardens. Unique crops included kalettes, papalo, thistle, savory, paw paw, quince, sea berry, and service berry, among others.

In terms of the soils, Mykl found that soils were within the recommended range for physical parameters, such as bulk density, wet aggregate stability, and soil compaction. However, home garden soils tended to be over-enriched in soil organic matter. Growers generally aim to foster soils that are between 3-6% organic matter. However, Mykl’s tested soils were on average 13% organic matter! Raised beds were on average 15% organic matter. In ground beds were a bit better: 10% organic matter, on average. So to put this another way, Master Gardener vegetable garden soils had 2-5X the recommended level of organic matter for productive agricultural soils. We suspect that Master Gardeners were annually adding organic matter to their soils, without necessarily knowing the baseline levels in their soils. Adding more organic matter, without knowing where you’re starting from, encourages over-applications.

Does that matter? Afterall, for years, we have been preaching that if you have sub-par soils, ‘just add organic matter’. Biological activity in these soils was great! But, the excess in organic matter promoted excess in several soil nutrients. Garden soils were over-enriched in phosphorus (mean phosphorus across all gardens was 2-3X recommended levels. Potassium in some gardens was 5X recommended levels! Gardens were over-enriched in magnesium and manganese, too. Nutrient excess was worse in raised beds, compared to in-ground gardens.

Unexpectedly, Mylk found the highest lead levels in raised beds. Often, we tell gardeners to grow their food in raised beds, to avoid heavy metal contaminants. Why would there be high lead in raised beds, if we weren’t finding elevated lead levels in nearby in-ground beds? We suspect that the lead might be coming in from compost waste that can be purchased on the retail market. If a compost product makes no nutritional claim, then it is exempt from analysis and contamination limits.

We can’t wait to finalize this work for publication. In the meantime, I wanted to share a brief update on this work.

Mykl will be defending his thesis on May 31st. We’re trying to arrange an online broadcast of the public portion of his thesis defense (1pm-2pm, May 31st). I will update this post, if we are able to get an online link for his presentation.

The Mining Bee

This entry is from Isabella Messer, an undergraduate horticulture student at Oregon State University. It highlights a common Oregon pollinator.

Halictus ligatus covered in pollen from the Morris Arboretum.

Halictus ligatus(Say, 1837), otherwise known as the Mining Bee and which can be classified as a Sweat Bee, are charming little(7-10mm) pollinators who are essential to our success as gardeners and farmers. These little generalists can be found worldwide in temperate climates with over 330 species recorded, so it would be no surprise if also you see them in your garden(1).

Halictus as a genus is very diverse in appearance with colors ranging from metallic greens, blues and sometimes even purple(2). Mining bees on the other hand, can be identified by their small dark brown or black bodies with well-defined yellow or black bands around their abdomens(3). Many of the females but no males will have scopa, which are long dense hairs on their hind tibia for carrying pollen(2). While they may not be the most flamboyant in their genera, their bodies are metallic and sparkle in the sun, giving them an understated but undeniable charm.

H. ligatus on an unidentified flower.

As their name suggests, Mining Bees build their nests underground and the Halictus gendera can demonstrate a very diverse gradation of social organizations within their nests(4). These organizations can range from solitary, communal, semi-social or eusocial(4).

If you are looking to attract some of these lovely and helpful pollinators to your gardens, be sure to leave a sunny and loose patch of soil close to some of your flowers available. Seeing as Mining Bees are broad generalists, there is no need to plant specific flowers or herbs to attract them. They will be beneficial for all of your flowering plants.

 

Sources

  1. Buckley, K., Nalen, C. Z., & Ellis, J. (2011, August). Featured Creatures: Sweat or Halictid Bees. Retrieved April 30, 2018, from http://entnemdept.ufl.edu/creatures/misc/bees/halictid_bees.htm
  2. Elliot, L. (2005, April 8). Species Halictus ligatus – Ligated Furrow Bee, Halictus (Odontalictus) ligatus. Retrieved April 30, 2018, from https://bugguide.net/node/view/14566
  3. Potts, S., & Willmer, P. (1997). Abiotic and biotic factors influencing nest-site selection by Halictus rubicundus, a ground-nesting halictine bee. Ecological Entomology,22(3), 319-328. doi:10.1046/j.1365-2311.1997.00071.x
  4. Rehan, S. M., Rotella, A., Onuferko, T. M., & Richards, M. H. (2013). Colony disturbance and solitary nest initiation by workers in the obligately eusocial sweat bee, Halictus ligatus. Insectes Sociaux,60(3), 389-392. doi:10.1007/s00040-013-0304-8

This entry is from Isabella Messer, and undergraduate horticulture student at Oregon State University. It highlights a common Oregon pollinator.

Photo by Marc Kummel

As winter starts to wind down, daffodils and crocuses begin to emerge, and butterfly enthusiasts start looking forward to another season of spotting some of my favorite pollinators, the Lepidoptera. While peak butterfly season still may be a ways off(5), there is no reason to delay in learning about and exploring the world of butterflies, as I have been doing these last few days with Ochlodes sylvanoides(Boisduval, 1852), or the Woodland Skipper.

These little beauties can be identified by their tawny upperwings which sport a black border and large red patches on their underside(1,2). The hindwings of the Woodland Skipper can vary greatly from being unmarked to being yellow or even showing a chevron pattern(1, 2).

Woodland Skippers are native to Oregon and in fact, are native to most of the western United States. With a range that stretches from South Dakota to Oregon and from Vancouver, BC to San Diego, CA, Skippers are one of the most abundant butterfly genera in the US(6,2). The preferred habitats of Woodland Skippers include grassy areas in chaparral, mountain meadows, and hillsides(1). For those of you living among

Photo by Claire Christensen

With Portland’s many hills, it seems likely that your garden would be an appealing place for these butterflies to make their home. If you are looking to attract some Woodland Skippers to your garden, this may not be terribly hard as O. sylvanoides are generalists. Larval food plants consist largely of common grasses such as bermuda, wildrye, wheatgrass, and canary(1,2). Adult food plants can vary widely, from Oregon natives such as yarrow, sweet pea, and willowherb to others such as catmint, tansy, and zinnia(1). If you are having a slow start to your gardening season and have lots of patches of exposed dirt, that is okay seeing as adult Woodland Skippers will also sip salts from mud puddles(1).

Keep the hope of summer and Woodland Skippers in your garden alive, as this winter season begins to come to an excruciating close, and when August(3,4) finally rolls around, keep your eyes open for these tawny beauties.    

References

  1. Lotts, Kelly and Thomas Naberhaus, et al. “Woodland Skipper”. Butterflies and Moths of North America. 2017. Butterflies and Moths of North America. http://www.butterfliesandmoths.org/
  2. Woodland Skipper — Ochlodes sylvanoides.  Montana Field Guide.  Montana Natural Heritage Program.  Retrieved on February 22, 2018, from http://FieldGuide.mt.gov/speciesDetail.aspx?elcode=IILEP72010
  3. Allen, Nancy., et al. “Create a Butterfly Garden”. 2002.  http://ir.library.oregonstate.edu/concern/administrative_report_or_publications/kd17ct04f
  4. Chu, Janet R.. “Butterflies A Continuing Study of Species and Populations In Boulder County Open Space Properties – 2011 Inventory and 2007-2011 Analyses”. Boulder County Parks and Open Space and Boulder County Nature Association. Dec. 2011. https://assets.bouldercounty.org/wp-content/uploads/2017/03/research-report-2011Chu.pdf.
  5. Kaufman, Kenn. “Year-round Guide to Butterflies”. Birds and Blooms. 2016.http://www.birdsandblooms.com/gardening/attracting-butterflies/year-round-guide-butterflies/
  6. Department of Systematic Biology, Entomology Section, National Museum of Natural History, in cooperation with Public Inquiry Services Information Sheet Number 189. “Butterflies in the United States”. Smithsonian. https://www.si.edu/spotlight/buginfo/butterflyus

It’s been a busy month in the Garden Ecology Lab.

  • Gail’s manuscript on bees in home and community gardens has been published in Acta Hort. Briefly, the results of this literature review are that: 213 species of bee have been collected from a garden habitat; gardens have fewer spring-flying and fewer ground-nesting bees, compared to non-garden sites; I suspect that over-mulching might be cutting out habitat for ground-nesting bees in gardens.
  • Aaron presented his first Extension talk to the Marion County Master Gardeners. This 90-minute talk was an overview of using native plants in home gardens.
  • The entire lab is getting ready to present their research results at the 2018 Urban Ecology Research Consortium annual conference, to be held in Portland on February 5th. A few highlights of our presentations, can be found below.

Gail’s Poster on Urban Bees: we sampled bees from 24 gardens in the Portland Metro area (co-authored with Isabella and Lucas)

  • Langellotto and Messer UERC 2018 Poster: click to see preliminary results
  • Most of the bees that we collected await identification. We did find a moderate relationship between lot size and bee abundance: larger yards hosted more bees. But, we also found evidence that suggests that intentional design can influence bee abundance: one of our smallest gardens (site 56 = 0.1 acre), located in the Portland urban core (surrounded by lots of urban development) had the second largest number of bees (42), of the 24 gardens sampled. This garden was focused, first and foremost, on gardening for pollinators. The plant list for this garden (photos, below) includes: borage, big-leaf maple, anise hyssop, globe thistle, California poppy, nodding onion, yarrow, fescue, goldenrod, Phacelia, Douglas aster, lupine, mallow, columbine, meadow foam, yellow-eyed grass, blue-eyed grass, coreopsis, snowberry, Oregon grape, trillium, mock orange, pearly-everlasting, serviceberry, coneflower, blue elderberry, currant, milkweed, dogwood, shore pine, crabapple, cinquefoil.

 

 

 

 

 

 

 

 

Mykl’s Poster on Urban Soils: we sampled soils from 33 vegetable beds across Corvallis and in Portland (co-authored with Gail)

  • All gardens were tended by OSU Extension Master Gardeners.
  • Gardens were over-enriched in several soil nutrients. For example, the recommended range for Phosphorus (ppm in soil) is 20-100 ppm. Garden soils averaged 227 ppm. The recommended range for Calcium is 1,000-2,000 ppm, but the mean value for sampled beds was 4,344 ppm.
  • Recommended ranges gleaned from OSU Extension Publication EC1478.
  • There was a tendency for soils in raised beds to be over-enriched, compared to vegetables grown on in-ground beds.
  • Data suggests that gardeners are annually adding additional soil amendments or compost, and that there has a build up of certain elements in the soil.

Aaron’s Talk on Native Plants: measured bee visitation to 23 species of native and 4 species of non-native garden plants (co-authored with Lucas)

  • Field plots established at the North Willamette Research and Extension Center
  • In the first year of establishment, of the 27 flowering plants that were the focus of this study, seven natives (lotus, milkweed, camas, strawberry, iris, sedum, blue-eyed grass) one non-native (Lavender) did not bloom, or else did not establish
  • Several natives attracted more bees than even the most attractive non-native (Nepeta cataria, or catmint). These include:
    • Gilia capitata: Globe Gilia
    • Madia elegans: Common Madia
    • Aster subspicatus: Douglas’ Aster
    • Solidago candensis: Goldenrod

All bees have been pinned, labelled, and data-based. Now we’re (and when I say ‘we’re’, I’m mostly referring to Lucas and Isabella) are going through the painstaking process of photographing all specimens: head on, from the top, and from each side. We’ll then start sorting them by morphotype (how they look), and working to identify them. Some of the bees are very common, and fairly easy to identify (like Anthidum manicatum, Bombus vosnesenskii, Apis meliifera). Others will take a bit more time and expertise to get to species.

You can take a look at the entire album, representing about 150 of the nearly 700 collected bees. We’ll be adding the rest of the bees, as we can.

We collect and pin the bees, because most are difficult to identify, without getting them under a microscope, and without the help of a museum-level bee specialist. For those bees that are easy to identify by site (such as the ones listed above), we only collect one per garden (so that we have a record of its presence). We don’t collect multiple specimens of the same species, if we can identify it in the field. And, we don’t collect obvious queens (larger, reproductive bees).

We collect using a combination of water pan traps and hand collection. For hand collection, we use a pooter (an insect aspirator) for the smaller bees and baby food jars for the larger bees.

Water pan traps. We buy plastic bowls from the dollar store, prime them, and paint them with UV paint that is optimized for the wavelengths that bees see.
Here, I’m holding an insect aspirator, otherwise known as a pooter. You can suck insects off of flower heads without damaging blossoms, by carefully placing the metal part of the pooter, over the bee. It is then sucked into a small plastic vial, which I’m holding in my right hand.

This is such an exciting part of the research for me. I find myself obsessing over the photos, trying to organize them in my mind, and to at least get them to genus. Grouping them by genus makes it easier for an expert to sort through and identify them. And, I’m so grateful for their assistance, that I want to make it as easy as possible for them!

We’ve collected bees from gardens near Forest Park, in Portland’s city center, and in outlying suburbs. We’ll analyze the data to see if there are any patterns associated with garden location (forest, city, suburbs), or to see if there are specific bees that are only found in forest gardens, for example.

 

This entry is from Isabella Messer, an undergraduate horticulture student at Oregon State University. It highlights a common Oregon pollinator.

 

Despite the misleading name, we have unfortunately not discovered a new cross species between California butterflies and tortoiseshell cats. Even though this butterfly has a larval stage instead of a kitten stage, the California Tortoiseshell Butterfly is still a beautiful representative of the Lepidoptera. 

A California Tortoiseshell flashes its bright upperwing. Photo by Doug Backlund

As you may be able to guess, the largest populations of the California Tortoiseshell (Nymphalis californica (Boisduval, 1852)) are located across California(1). While the majority may be in California, the California Tortoiseshell habitat range stretches south from British Columbia to Mexico and east from California to Wyoming(1). When the California Tortoiseshells experience a population explosion in the summer(1), some populations have been known to travel as far east as Vermont, New York and Pennsylvania(2). 

These lovely butterflies can be identified by their bright orange upperwing which features black spots and black border(1). Their underwings are mottled brown and gray and resemble dead leaves(2). When in larval(caterpillar) form, N. californica can be identified by its all-black appearance with the exception of a white line running down its back and the slight blue at the base of its black spines(2).

The cleverly disguised underwings of the California Tortoiseshell. Photo by Doug Blackbund

Unlike some of the other pollinators that we have discussed over the months, the California Tortoiseshell Butterfly is somewhat picky when it comes to choice of host plant for the immature and habitat mature butterflies. Adults will oviposit (lay eggs) only on various species of wild lilac (Ceanothus) where the immature butterflies will be hosted until they reach maturity(3). Adult N. californica are less specific about their habitats by the time the reach maturity. They can generally be found in mountainous regions in chaparral, woodland and brush areas(1). 

While these charming butterflies may not be extremely common in the Portland area due to its low elevation, if you take a trip up to Mount Hood this coming summer, it is more than likely you will run into one of these beauties.

Sources:

  1. Lotts, Kelly and Thomas Naberhaus, et al. “California Tortoiseshell”. Butterflies and Moths of North America. 2017. Butterflies and Moths of North America. http://www.butterfliesandmoths.org/
  2. Ross A. Layberry, Peter W. Hall, and J. Donald Lafontaine. “California Tortoiseshell”. Canadian Biodiversity Information Facility. 9 Jul. 2014. http://www.cbif.gc.ca/eng/species-bank/butterflies-of-canada/california-tortoiseshell/?id=1370403265564
  3. Art Shapiro. “Nymphalis californica”. Art Shapiro’s Butterfly Site. http://butterfly.ucdavis.edu/butterfly/Nymphalis/californica