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Notes from the Field: Willamette Mainstem Cooperative in 2021

By Troy Abercrombie | October 29, 2021
Michael Ahr and Tamra Dickinson going after Ludwigia and Yellow floating heart on the Willamette this past summer.
Michael Ahr and Tamra Dickinson going after Ludwigia and Yellow floating heart on the Willamette this past summer.

This blog post was initially shared in the Western Invasives Network Quarterly Newsletter: Autumn 2021. View the original article here. Thanks to Troy Abercrombie and Cascade Pacific Resource Conservation and Development for shining a spotlight on Michael Ahr and the Willamette Mainstem Cooperative!

In April of 2021, Benton SWCD welcomed Michael Ahr as their Natural Resources Conservation Program Manager. Michael has taken over as the Coordinator of the Benton County Cooperative Weed Management Area (CWMA) as well as the Willamette Mainstem Cooperative, as Laura Brown was, but he also has taken on the oversight of multiple conservation programs and supervises two other conservation planners.

Michael comes to Benton SWCD with a wealth of experience after spending time at Polk SWCD as a CREP Technician planning streamside planting projects and with Washington Department of Natural Resources as an Outreach Specialist to small forest landowners. Most of you likely got to know Michael at West Multnomah SWCD, however, where he served the last 11 years as a forester who spent plenty of time in the invasive species arena. While at WMSWCD he once masticated 13 acres of English Holly!

Michael immediately hit the ground running as he and his team took on multiple inventories on the Willamette this summer, searching out Ludwigia and yellow floating heart and complementing the work of colleagues from Willamette Riverkeeper. Yellow floating heart sites looked promising with multiple sites having zero surviving plants after previous treatments and more sites with very diminished yellow floating heart. They did find new sites near Takena Landing in Albany and at Black Dog Landing near Buena Vista. Both sites were promptly treated.

Don't call it a comeback! With persistent attention to the invasives in Wapato Cove, its namesake plant is thriving!
Don’t call it a comeback! With persistent attention to the invasives in Wapato Cove, its namesake plant is thriving!
Richard Dickinson, Willamette Riverkeeper, going DEEP into the Ludwigia that still remains in Collins Bay.
Richard Dickinson, Willamette Riverkeeper, going DEEP into the Ludwigia that still remains in Collins Bay.

Ludwigia control was focused at Wapato Cove, Lower Kiger Island and in Collins Bay, near Hyak Park. Wapato Cove is looking great! Wapato populations were making a strong rebound and Ludwigia was limited to a couple small sites that were easily hand-pulled. Lower Kiger is getting worked on by contractors and volunteers and the Ludwigia is under control and on the way out. Collins Bay has improved but there is still much work to be done. Contractors will continue to focus on that area while Michael takes a deeper look at the variability in treatment efficacy from one site to another. Support from the Oregon State Weed Board and Willamette Riverkeeper has been crucial in these efforts and Benton SWCD/CWMA look forward to continued partnership.

Oblong spurge infestations gave Michael and the SWCD an opportunity to engage with the community through educational outreach and those efforts yielded 11 new reports of the pesky plant. Many of these sites were confirmed and have been prioritized for immediate eradication. The SWCD was also able to partner with Oregon Department of Agriculture and private contractors to address multiple other sites and the oblong spurge outlook is favorable with continued diligence.

For more information on Benton County CWMA, the Willamette Mainstem Cooperative, or any of the other services that Benton SWCD provides, please reach out to Michael via email!

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About the Author

Troy Abercrombie

Troy joined the Cascade Pacific team in 2019 as the Coordinator for Western Invasives Network. He has a BS in Rangeland Science from Oregon State University and lives in Sweet Home with his wife and two daughters. Now specializing in the development and implementation of watershed scale invasives projects, Troy has spent most of his career in public service having worked on 5 national forests for the US Forest Service and as a county weeds program coordinator with some government contracting and university research sprinkled in between. Troy grew up in the Pacific Northwest and still loves nothing more than to explore everything it has to offer with his family. When not working, he likes building Legos with his girls, fly fishing, kayaking, expedition rafting, flying his stunt kites and listening to baseball on the radio. Troy is also a multi-award winning photographer with an affinity for 35mm film.

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