The team that created the Oregon Bee Atlas and the Oregon State University Extension Service Master Melittologist Program has launched an interactive website that packs a powerful punch in expanding public awareness of Oregon’s native bees.
The Melittoflora (meh-lit-toe-flaw-ruh) is a data visualization tool that allows Oregon to lead the way in restoration for our 700-plus native bee species, according to Andony Melathopoulos, an associate professor of pollinator health Extension in OSU’s College of Agricultural Sciences.
The Melittoflora, which visualizes about 106,000 records of individual bees visiting plants, is the largest bee-plant interactive network in the world, according to Melathopoulos. It empowers users to explore species occurrence records of bees interacting with flowering plants.
“This tool allows you to explore the hundreds of bees and how they visit the thousands of flowers throughout the landscapes and all of the ecosystems,” said Lincoln Best, an OSU faculty research assistant, educator for the Master Melittologist Program and taxonomist for the Oregon Bee Atlas project.
Melittology is the study of bee diversity. The data that drives the Melittoflora is compiled by Master Melittologists who roam the state searching out wild bees and the plants that support them. The results provide a snapshot of the current range of each species to better assess their status prior to federal evaluations, according to Melathopoulos.
The Melittofora tool was funded by a grant from the U.S. Department of Agriculture’s National Institute of Food and Agriculture, but the data going into the tool is supported by the purchases of Oregon’s “Pollinator Paradise” license plate.
Museum-worthy collection
The Master Melittologist Program started in 2018. It was the first program of its kind in the world, designed to train community scientists to collect and curate bee specimens for university-led studies. Those who complete the intense training will reach journey level as a Master Melittologist, who collect and curate specimens of native bees for the Oregon Bee Atlas.
About 500 people have enrolled in the Master Melittologist Program. The framework of having Extension volunteers provide data for state and provincial Atlases is being replicated in Washington, Idaho and British Columbia.
Master Melittologists who are part of the Oregon Bee Atlas initiative conduct field work that is comprised of taking photos of a flowering plant species use a butterfly net to capture bees visiting the flowering plant host. They document the bees they collect, which they then place in a box and donate to the Pollinator Health Program’s lab at OSU. The specimens are archived in the Oregon State Arthropod Collection.
“They’ve collected 150,000 bee specimens,” Best said. “It’s a museum’s worth of bees. We think our program is the most productive in the world. We’re documenting bees visiting virtually all the native flora in Oregon.”
The value of the data in the Melittoflora stretches beyond those who just want to learn more about bees. If land managers know where the bees are, they could employ enough resources to keep bees healthy and off the threatened or endangered lists of the Endangered Species Act.
“This is going to be a valuable resource for soil and water conservation districts, federal and state agencies and anyone doing land restoration and management,” Best said.
Debate Settled: Native Plants Attract more Pollinators than Cultivar Plantings
In other pollinator news, OSU researchers have settled a longstanding question about which plants pollinators prefer.
Planting native plants is a popular way to help support pollinators like bees, butterflies and other beneficial insects.
But when shopping for native plants, people often come across something called a “cultivar.” This is a special version of a native plant that have been selected or bred to have certain traits, like different flower colors or shapes. These cultivated plants can look and behave a bit differently from the wild versions.
Researchers have been trying to figure out whether pollinators visit wild native plants more than they do cultivars, but past studies haven’t been consistent in their results. According to Jen Hayes, a recent Oregon State University graduate, the findings were all over the map.
For her dissertation on native plants, their cultivars and pollinators, Hayes led a garden experiment at the OSU Oak Creek Center for Urban Horticulture in Corvallis that used a mix of wild native plants and their cultivated versions.
Over three years, Hayes and colleagues in the OSU Garden Ecology Lab watched and collected data on bees, butterflies and flower flies to see whether pollinators preferred one over the other, if certain pollinators favored certain types of plants, and if specialist pollinators — those that rely on specific plants — chose wild natives more often.
It was the first study of its kind to look closely at how pollinators like bees and butterflies interact with both wild native plants and their cultivated versions in the Pacific Northwest.
What they found was that pollinator visits depended a lot on the specific plant and insect. When comparing native plants with their cultivars, pollinators favored the wild versions about 37% of the time. Cultivars were preferred only about 8% of the time.
In more than half the cases, there was no clear difference.
“We found that visitation is dependent on the specific pollinator group and the plant group,” Hayes said. “When we did see a difference in vastation rates, more often the native plant had a greater vastation rate than the cultivars. The cultivars that did have higher visitation rates tended to be those minimally developed cultivars.”
The study is published in the journal Environmental Entomology.
Hayes cautioned that the results are based on a specific group of plants and a specific community of pollinators in one location, so that means results might vary in other regions, with different plants or under different environmental conditions.
For example, the researchers observed many specialist bees — those that only visit certain types of flowers — and especially one group that’s common in the central Willamette Valley. That’s not always the case in other studies, Hayes said.
What are native cultivars, exactly?
A native cultivar is one that has been selected from a native population or a cross that’s been developed by humans, said Signe Danler, online instructor for the OSU Extension Service Master Gardener program. Breeders select for characteristics that people are drawn to, such as larger and more abundant flowers, a variety of colors, longer bloom or more compact form.
The cultivars are distinct, uniform and stable, meaning they will remain the same with each generation. The best way to tell the difference is that a cultivar will have its name listed in single quotes after the scientific name as in Echinacea purpurea ‘White Swan.’
“When we create cultivars, we create a version of a native as we like it,” Danler said. “And since many are propagated clonally (from one cell) they never change. Genetic variability stops.”
It’s not harmful to grow cultivars in the garden, Danler said, but they should never be used in restoration projects, where genetic variability is key so plants can adapt. Cultivars of native plants are propagated to minimize genetic diversity in favor of uniformity.
Pollinator-preferred plant groups
For the study, Hayes divided pollinators into categories: all pollinators, wild bees, bumble bees, leafcutter bees, longhorn bees, syrphid flies and butterflies to represent the diversity of the pollinator population at Oak Creek.
There were only two plant groups where pollinators seemed to consistently prefer the native plant, including Clarkia amoena or farewell-to-spring, and Eschscholzia californica or California poppy. The plant with the strongest storyline, however, was Clarkia, Hayes said. Pollinators in five groups preferred the species over the cultivar, which could be because the species blooms longer and, in more abundance, so pollinators have more time and flowers to visit.
There were some pollinator groups where yarrow (Achillea millefolium) and Douglas aster (Symphyotrichum subspicatum) cultivars were more visited by pollinators than the species. Yarrow by honeybees; Douglas aster by honeybees, bumble bees and the all-pollinator group.
“The cultivars we used represent a spectrum of plant breeding modifications,” Hayes said. “Some just had a different flower color or a change in foliage like variegation. Others were more developed, like interspecific hybrids, which are plants resulting from parents of at least two different species. All the cultivars had a wild-type native plant somewhere in its pedigree.”
Don’t ‘villainize’ cultivars
People used to believe that pollinators stuck to specific flower colors — bees to blue and yellow, butterflies to red and so on. But in this study, bees visited a wide range of flower colors, including pinks and purples. What really seems to matter is a mix of traits like nectar quality, bloom time, flower size and even how flowers are arranged on the plant, according to Hayes.
“Some groups are fervently anti-cultivar,” Hayes said. “I don’t think that’s fair. I came into the study thinking that I preferred natives just because I had assumptions about the ecological benefits. There is intrinsic value to planting native plants in the landscape, but it’s not fair to villainize cultivars.”
Hayes said cultivars can be valuable, like in the case of American chestnut trees that were decimated by the chestnut blight in the early 1900s.
“There might not be American chestnut trees left in the country if breeders weren’t working on developing resistant cultivars,” Hayes said. “It was a way to potentially restore a keystone species. In some ways, cultivars can be ecologically important and should be used. Or if someone wants to have their favorite plant in every color or a special cultivar that means something to them, who am I to tell them not to?”
The study was funded by grants from the Native Plant Society of Oregon, the Garden Club of America and Sherry Sheng.
By Chris Branam and Kym Pokorny, Photo by Andony Melathopoulos
Do you have a story for The Advocate? Email editor@corvallisadvocate.com