Growers looking to learn more about use of hedgerows for improving blueberry pollination and enhancing beneficial insect populations can do so at a field day, scheduled May 22 at Hopville Willamette Farm in Independence. The field day is sponsored by OSU Extension, the USDA-Agricultural Research Service, Pollinator Partnership and the Polk Soil and Water Conservation District.

Workers plant a hedgerow in Independence, Oregon, in September of 2024. Hedgerows are becoming popular as a means to enhance pollinator health.

Featured speaker at the field day is George Kaufman, an agronomist for AgriCare. Kaufman has been planting and maintaining hedgerows since 2014.

Use of hedgerows, while still relatively rare, is becoming more common on blueberry farms of late, Kaufman said, particularly as growers seek Bee Better certification from the Xerces Society. A main pillar of the certification, which is a means for farmers to show buyers that they are committed to protecting beneficial insects and enhancing pollinator habitat, is that five percent of a farm be dedicated to beneficial insects and pollinator habitat.

“That is a practical reason that growers are planting hedgerows,” Kaufman said. “And then some of our clients just believe in regenerative agriculture and they believe in conservation, and they want us to take care of the native flora and fauna around their farms.”

Hedgerows bring multiple benefits to a farm, Kaufman said, including enhancing natural enemies of insect pests. “A lot of these farms that we’re working on are organic, so there’s not a lot of tools to be able to control insect pest populations,” Kaufman said. “These hedgerows help boost the amount of beneficial insects and predatory parasitoid insects in a field. We’ve actually seen that the closer you are to the hedgerow, the fewer aphids there are in blueberries, because those beneficial insects are moving out to the blueberries and feeding on the aphids.”

And hedgerows provide pollination benefits, something blueberries can always use more of, Kaufman said.

“Blueberries are notoriously difficult to pollinate with honeybees,” he said. “Their pollen tends to be a little bit lower in nutritional value than some crops and honeybees aren’t that attracted to them. Conversely, native pollinators, especially bumblebees, are really good at pollinating blueberries. They can access the pollen easier than honeybees can, and they tend to work in cooler weather conditions than a honeybee will.

“So, we’re not trying to replace honeybees, but we’re trying to have a layer of insurance in there,” Kaufman said. “And by planting plants that flower all summer long, we can keep the bumblebees on the farm, and we can help boost our populations that overwinter, and around the pollination time for blueberries, they will be out there pollinating.”

Selecting which plants to install in a hedgerow is not something growers should take lightly, said Andony Melathopoulos, Oregon State University Extension Pollinator Specialist, who will also be presenting at the field day. The wrong plant, one that produces fruit and attracts spotted wing drosophila, can in fact have negative effects on an operation.

The key is to select plants that support beneficial insects, but that don’t support insect pests or plant diseases, said Melathopoulos, who is working on a project with researchers from across the country to create a user-friendly database identifying the best plants to use in hedgerows around blueberries.

Researchers from Michigan, Washington, Vermont and California are working with the nonprofit Pollinator Partnership on the two-year project. The Hopville Willamette Farm field day is part of the project’s outreach.

Planting Costs

Hedgerows vary widely in size and appearance, according to Kaufman. Some commercial scale growers will plant native plants in long rows with raised beds, weed fabric and drip irrigation systems, essentially mimicking a blueberry planting. Others will clump a few native plants next to a blueberry field within minimal planting costs. In both cases, extensive benefits are attainable, Kaufman said.

“They can be any size, don’t required weed fabric and expensive irrigation systems and can be tucked away in any corner of the farm,” Kaufman said. “They are especially a great option for planting in an area that is unfit for farming, such as an area that is too steep, too narrow or an odd-shaped corner.”

The return on investment of a hedgerow can be hard to quantify, Kaufman said, and has not been well documented. But, Kaufman noted that AgriCare has seen strong evidence of increases in beneficial insect populations in fields where hedgerows are in place. “And I think the conclusion to draw from that is we are seeing a benefit in pollination,” he said. “On farms where we have a lot of pollinator habitat, we have seen that one-quarter to one-third of the pollination that is done in blueberries is being done by these native pollinators. And those are free services that we’re getting from these insects.”

It is also notable that Bee Better Certification can help show the public and food companies that a farm cares about pollinator health and is doing something to enhance it, said Beth Thiel of the Polk SWCD, who helped secure a state grant that offset some installation costs of the most recent Hopville Willamette Farm hedgerow.

“Every farm is different, and they have different goals,” Thiel said. “But it is good to see when farmers’ goals overlap with goals that are beneficial to the environment and to wildlife. I mean, that is what we aim for at the Conservation District.”

In addition to OSU Extension, presenters at the field day include representatives from Polk SWCD, USDA-Natural Resources Conservation Service and Pollinator Partnership.

Hopville Willamette Farms is located at 5340 Wigrich Road in Independence. The field day will run from 9 to 11 a.m. and is open to the public, but pre-registration is required.

To register, contact the Polk Soil and Water Conservation District at 503-623-9680.