The Prickly Thistle: A November 2017 WeedWise update

A WeedWise Update

If you have ever visited the Clackamas SWCD and WeedWise program you know we are busy. District staff are hard at work on a variety of conservation efforts. We work on everything from irrigation improvements to urban wildlife habitat, from forestry to prairie-oak preservation, from invasive weeds to water quality, and from mud and manure management to riparian restoration. With this broad diversity of activities, we recognize that sometimes the greatest barrier to conservation is not knowing what is possible or where to start on your property. This is why we are trying something new here at the Clackamas SWCD! We are pulling back the curtain to show you some of the many activities happening here at the Clackamas SWCD.

Each week we will be highlighting activities from one of the Clackamas SWCD program areas. So check back every week to learn more about our efforts. Remember to contact the Clackamas SWCD for assistance with conservation practices on your property!

This week we are featuring the Clackamas SWCD, WeedWise program. So enjoy the WeedWise program’s new newsletter that we are calling the Prickly Thistle. Happy Pulling!

Samuel Leininger

WeedWise Program Manager

The knotweed final sprint

Japanese Knotweed

Japanese knotweed

Why knotweed

The knotweeds are some of the worst invasive weeds we have in Clackamas County. Currently ranked 37th on the 100 worst global invasive species list these weeds have a profound impact on Clackamas County. The invasive knotweeds include Japanese knotweed (Fallopia japonica), Giant knotweed (Fallopia sachalinensis), and a hybrid known as Bohemian knotweed (Fallopia × bohemica). These invasive weeds were introduced as garden plants, but have since spread to invade areas along streams and river where they displace our native plants, increase erosion, reduce water quality, and harm fish.

Our approach

The invasive knotweeds can be incredibly difficult to control. Cutting and digging is ineffective and can actually spread the knotweed. As a result, a carefully timed herbicide application is the most effective control method. Spraying rather than digging or cutting prevents the spread of plants further downstream and minimizes soil disturbance. The timing of knotweed treatment is critical. In the fall, knotweed plants pull nutrients from leaves down into their root system. As the season progresses the plants die back for the winter only to push new shoots up again in spring. Applying herbicides when plants are pulling nutrients into their root system causes roots to die. This is the best control option on these difficult-to-treat plants. The downside is that there is only a narrow window of time to treat the knotweed from late summer to fall leaf drop.

A dash to the finish

We always feel an increasing pressure to treat as much of the knotweed as possible before plants start dropping their leaves and the fall rain and wind arrive. Fortunately, the weather this season has been very cooperative and the WeedWise program has been taking full advantage to finish up our knotweed control efforts. So as November begins, we will wind down our knotweed control and begin working on our many other responsibilities.

Below are just a few photos of our October control work. To learn more about the invasive knotweeds, check out our Invasive Knotweed Weed Profile and the WeedWise Knotweed Brochure.

It’s not the fish, it’s the people

Save the Fish

These juvenile fish took a short trip from their rapidly shrinking puddle to the mainstem Clackamas River, thanks to WeedWise specialist, Lindsey Karr.

Why we do what we do

The WeedWise program works hard to control invasive weeds for a variety of reasons. We target invasive weeds because they threaten agricultural crops and livestock, pose a health threat to human health, impact our natural areas and open spaces, reduce water quality, and pose a threat to fish and wildlife. Much of our weed control work is focused on water quality and fish habitat. Fortunately, we are blessed to have WeedWise specialists that are deeply concerned about the impact of invasive weeds on fish health. This shows in the quality of their work, and in their thoughtful decision making.

Its good to be a fish

Nothing tells the story about the motivation of our team more than a recent story from WeedWise Specialist, Lindsey Karr. She was recently out on the Clackamas River surveying and treating knotweed. Recent flooding along the river had swept through an area she was surveying, but as the water receded it left several small and rapidly shrinking puddles. Lindsey spotted in one puddle a number of juvenile fish that had become trapped. So she grabbed a plastic bag from her pack and collected the fish for a quick trip back to the river. Although the puddle was literally a drop in the bucket, this action speaks volumes about the motivation and dedication of WeedWise program staff. So on behalf of the fish in the bag, we say thanks to Lindsey!

Getting a fall jump on garlic mustard

Garlic mustard

Garlic mustard

A new approach

Garlic mustard is a priority invasive weed in Clackamas County. Following our Best Management Practices for Garlic Mustard, the WeedWise program spends much of our spring treatment season working to control this highly invasive plant. This month, the WeedWise program has begun experimenting with a fall garlic mustard control effort. Treatment at this time of year targets seedlings and small rosettes in an effort to prevent the development of mature plants in the coming season. Our hope is that these fall treatments will also help exhaust the garlic mustard seeds that lie dormant in the soil seed bank.

Building on experience

These fall treatments have been used by several of our 4-County Cooperative Weed Management Area partners, but this will be the first season that we experiment with this approach. Normally fall WeedWise control efforts are dedicated to the treatment of knotweed. In past years, we have had little overlap between our knotweed and garlic mustard treatments sites, but as we continue to expand our control efforts we are now seeing a greater overlap between these two species. This approach provides a greater opportunity to treat both knotweed and garlic mustard during our fall treatment efforts.

Our current efforts

The WeedWise program experimental garlic mustard and knotweed treatment sites are located within the Clackamas Basin and in the Lad Hill area near Wilsonville. The Ladd Hill infestation is one of the most important sites in the region. It is currently the most upstream known infestation of garlic mustard along the Willamette River. As such, this infestation has the potential to impact all areas downstream of the infestation.

Below are some photos of our fall garlic mustard treatment efforts. To learn more about garlic mustard check out our Garlic Mustard Weed Profile and the WeedWise Garlic Mustard Brochure.

WeedWise messaging highlighted at the Play Clean Go Summit

Play Clean Go logo

The WeedWise program is one of 461 Play Clean Go partners across the United States working to spread the word about preventing the spread of invasive species. Stop Invasive in Totality PosterWe recently received word that some our outreach efforts to raise awareness about invasive species introductions during the recent solar eclipse was highlighted at the most recent Play Clean Go and North American Invasive Species Management Association conference.

One of our partners from the Oregon Department of Agriculture Noxious Weed Program sent over the following message:

“I’m attending the Play Clean Go summit in Reno right now and you guys just got a big shout out for your “Stop invasive species in Totality” messaging!! Way to go…”

We are happy to see that our messaging has cast a shadow (sorry, we couldn’t resist!) of awareness about invasive species prevention to conference attendees from across the county.

More importantly we hope that you remember to Play Clean Go 

Remove: plants, animals & mud from boots, gear, pets & vehicle.

Clean: your gear before entering & leaving the recreation site.

Stay: on designated roads & trails.

Use: certified weed free hay and local firewood.

Clackamas River Invasive Species Partnership


Good partners make good work

CRISP Annual Report 2016The WeedWise program is a founding member of the Clackamas River Invasive Species Management Partnership. Affectionately called the CRISP, this growing partnership is composed of 13 different public and non-profit organizations working to control invasive weeds and restore natural areas within the Clackamas River Basin. The CRISP is focusing on working cooperatively across boundaries and between organizations.

Annual report

The CRISP recently completed the CRISP Annual Report for 2016. This report highlights the many activities and accomplishments of the partnership over the last year. CRISP partners reported expending more than $737,608 controlling weeds on more than 2,836 acres within the Clackamas River Basin. That is a lot of work completed, especially in the first year of a partnership! Many thanks to all of our CRISP partners working within the Clackamas River Basin.

Additional efforts are progressing in 2017, so if you are living in the Clackamas Basin get ready to see more work and fewer weeds!

Work underway

Work in the Clackamas River Basin continues. WeedWise Specialists Lindsey Karr and Jeff Lesh have been coordinating Early Detection and Rapid Response surveys in the upper portions of the basin to detect new invasives before they have a chance to establish. These surveys are currently wrapping up and we are excited to put this information to use in the coming season.

Lindsey is also coordinating CRISP funded projects with a number of our CRISP partners. Much of the fall implementation has been completed, and we are working with our partners to wrap up last minute details before the end of the treatment season.

Cooperative Weed Management Areas

The WeedWise program is very active with our local Cooperative Weed Management Areas (CWMA). We have two CWMAs active in Clackamas County, including the 4-County CWMA that serves that Portland-Vancouver Metro region and the Columbia Gorge CWMA that serves the Columbia River Gorge and surrounding areas. The WeedWise program currently administers both of these CWMAs. WeedWise Specialist Sarah Hamilton serves as a shared part-time coordinator for both CWMAs. As such, much of our work here at the WeedWise program influences and is influenced by our CWMAs. Below are some of the highlights of activities currently underway by our local CWMAs.

4-County CWMA

4-County CWMA logoThe 4-County CWMA recently hosted its fall general meeting in Clark County, WA. The meeting provided a great opportunity to learn more about weed control activities underway by our partners in Clark County. We were fortunate to learn about many of the new and emerging invasive weed threats we both share.

At the general meeting, attendees also learned about weed control and agricultural practices designed to promote habitat for sandhill cranes and other migratory birds and wildlife. There was great information about utilizing agricultural practices designed to benefit migratory birds on former production fields along the Columbia River.

Attendees also learned about weed-free hay and straw certification efforts in the State of Washington. Certified weed-free hay and straw is required on all state and national forest lands. A similar certification process is also underway in Oregon. Interested producers should contact the Oregon Department of Agriculture’s Weed free forage program for additional information.

The 4-County CWMA is also focused on planning for its annual Pull Together conference. This year’s event is tentatively scheduled for January 10th at McMenamin’s Kennedy School. The Pull Together will focus on the impacts of climate change on invasive weed distribution, physiology, and abundance. So mark your calendars for this popular event.

Columbia Gorge CWMA

Columbia Gorge CWMA logoThe Columbia Gorge CWMA also hosted a general meeting in Hood River. The primary topics discussed were associated with recovery following the Eagle Creek fire. Recovery efforts in the area are severely hampered by the risk of landslides and tree and rock fall in the burn area. The affected areas are closed to all visitors and citations are being given to anyone observed in the area.

We received updates from a representative of the Mt Hood National Forest and from the Columbia River Gorge National Scenic Area. Planning efforts are already underway for the area. The Forest Service will be working with partners from the Columbia Gorge CWMA to focus on prevention and early detection of invasive weeds to protect these sensitive areas.

A representative from the Burned Area Emergency Response (BAER) team was also on hand to share some of their preliminary findings. The BAER team is currently working to finalize their report for post-fire planning by the Forest Service in an effort to help stabilize the affected area.

The Columbia Gorge CWMA partners also discussed messaging and outreach plans to help spread the word about invasive weeds in the recovery area. Additional work is planned for some maintenance and improvements to CWMA boot brush stations within the Columbia River Gorge.

The Columbia Gorge CWMA is also pleased to announce that we have reprinted our updated Worst Weeds of the Gorge field guide. We encourage folks to download the guide or stop by the Clackamas SWCD office for a free copy!

Planning has begun for the annual Invasive Species and Exotic Pest (ISEP) workshop. This year we will focus on post fire recovery, weed control, and prevention. The ISEP workshop is tentatively scheduled for March 1, 2018 at the Hegewald Center in Stevenson, WA. This annual event also coincides with National Invasive Species Awareness Week. So mark your calendars!

More WeedWise Online and on Social Media

WeedWise header

Did you know that the WeedWise program also hosts a website online that specializes in invasive weed related issues. Be sure to check out the website and read some of our recent articles over the last month.

The WeedWise program is also active on social media, so be sure to follow us online.

Facaebook Twitter

 We hope you’ve enjoyed the new Prickly Thistle!

Thanks for your interest in the Clackamas SWCD WeedWise program

, , , , , , , , , , , , , , , , , , , , ,

Clackamas SWCD