Name:   Birdie Davenport

Name:Brent Lackey

Job Title: Watershed Planner

Agency or Organization: Seattle Public Utilities (SPU)

Mailing Address:  19901 Cedar Falls Rd S.E.

Phone:206-615-1926  Email:    Brent.Lackey@seattle.gov 

 Title of Presentation: Non-Herbicide treatments & results

Summary of Main Points:

            In the Cedar River Municipal Watershed (CRMW), polygonum cuspidatum has been a minor problem for more than 20 years, but severe spreading and infestation of large multi-acre patches has occurred over the past few years.  The infestations are very rapidly growing where left unchecked, predominantly  (and not surprisingly!) along roadways and stream riparian areas.

            Because of our primary function as the provider of high quality drinking water to over 2 million King County residents, we are precluded from herbicide use, but that does not lessen our concerns over invasive plant species such as Japanese knotweed.

            We are currently experimenting at small to moderate scale with several “constant cutting” abatement techniques, but have also engaged in one major eradication project in the CRMW, known as “Road 16 Restoration”.  This project used a large tracked excavator to over-excavate the road prism material of a forest road that was running through a large (20+ acre) high quality wetland.  The goals for the project were hydrological restoration and knotweed eradication.  For a portion of approximately 2000-feet the road shoulder was heavily infested with polygonum cuspidatum and likely some of the hybrid giant/Japanese knotweed species Polygonum X bohemicum.  The eradication of this 2000’ long X 10-20’ wide patch began with manual grubbing during several volunteer events; then later was followed by the mechanized over-excavation (to a depth of approx. 16”), followed by one growth season of monitoring; followed by cutting, covering (with long strips of black visquene), and current season bi-weekly manual “edge-maintenance” of pulling new tiny shoots trying to grow outside of the covering.

            As the end of the current growing season approaches it appears that the covered patches of re-growth following excavation are being very successfully eradicated (the excavation contributed greatly to the effectiveness of covering).  Significant edge shoots have been popping out from under the covering all summer, but after pulling/cutting these bi-weekly through the growth season, the vigor of new shoot activity seems to have significantly lessened.

            We intend to leave the plastic cover in place for at least two additional years while planted and naturally recruited native vegetation become better established and the knotweed patch continues to spend its reserve rhizomatous energy sending out new shoots, which we intend to continue cutting bi-weekly through the necessary required growth seasons.  We believe that the frequent maintenance is the only way this project will see eventual success in eradicating this large patch of knotweed.

Name:  Cathy Lucero

Job Title: Clallam County Noxious Weed Control Coordinator

Agency or Organization: Clallam County Noxious Weed Control Board

Mailing Address: 223 E. Fourth St., Suite 15, Port Angeles, WA 98362

Phone: (360) 417-2442  Email: clucero@co.clallam.wa.us 

Title of Presentation: Injection: A Dose of Reality

Name: Sean MacDougall

Job Title: Noxious Weed Specialist

Agency or Organization:  King County Noxious Weed Control Program

Mailing Address: 201 South Jackson Street, Suite 600, Seattle, WA, 98104

Phone:  (206) 296-0290     Email: sean.macdougall@metrokc.gov 

Title of Presentation: Green/Duwamish CWMA Update

Summary of Main Points:

The Green/Duwamish CWMA project’s intent was to develop a coordinated watershed approach to controlling the knotweed species group (Polygonum cuspidatum, P. sachalinense, P. bohemicum) along the middle and upper sections of the Green River enhancing the quality of riparian habitat.  Previous surveys identified the Green/Duwamish watershed as the least infested with knotweed and contains some of the largest high-quality managed public lands within King County.  The Green River is also an important salmonid spawning area for steelhead, cutthroat trout and several species of salmon including the threatened Puget Sound Chinook. 

There has been strong interest in controlling knotweed along the Green River from our key stakeholders who recognize the very visible impact knotweed has in wetlands, riparian areas, and roadside ditches.  In 2004 this project was awarded a $34,665 Cooperative Forestry Assistance Grant from the USDA Forest Service which was more than matched by King County Noxious Weed Control Program.  This funding was used to establish a baseline of knotweed distribution, hire contractors to control knotweed infestations, and produce a report summarizing the results of the project.

The Green/Duwamish River is 93 miles long and the entire watershed encompasses 355,000 acres.  Our highest priority for the project was to survey and control any knotweed infestations in the upper watershed.  Tacoma Public Utilities, which manages the Howard Hansen Reservoir in the upper watershed identified two infestations on their land, one 10,000 sqft site 9 miles upstream from the headworks and several scattered patches near the headworks gate.  These sites were controlled using the stem injection method by Earthcorps and King County Noxious Weed Control Program staff in 2004.

30.9 miles of the middle Green River were surveyed in 2004 by stream walking, car surveys, and kayaking starting from the Howard Hansen Reservoir headworks to Auburn Narrows park downstream from the Soo’s Creek/Green River confluence.  10 sites were found along the mainstem Green River and 8 were controlled in 2004 by stem injection.  In addition 18 sites were located and controlled on creeks, and adjacent wetland and upland sites.  Roughly 7 acres of knotweed was controlled in 2004 using a variety of techniques including stem injection, foliar application, manual control, mowing, and sheet mulching with heavy grade geotextile fabric. Control work was performed by landowners/CWMA stakeholders, restoration crews from Earthcorps and Washington Conservation Corps, and King County Noxious Weed Control Program staff. 

Preliminary surveys were conducted along major creeks that feed into the Green River including Soo’s Creek, Jenkin’s Creek, Covington Creek, and Newaukum Creek.  Soo’s Creek is heavily infested and 11 restoration crew days were spent controlling knotweed at an existing restoration project, a Washington State Department of Fish and Wildlife hatchery, and several adjacent private properties.  A more comprehensive survey on all major creeks will be a goal for 2005 to improve the baseline of knotweed distribution.

The Green/Duwamish CWMA was the first watershed based weed control project conducted by the King County Noxious Weed Control Program and the success in 2004 is part of a multi-year strategy for eliminating knotweeds along the Green River.  With additional funding our goals for 2005 include follow up treatment on existing sites, additional surveys on smaller creeks in the middle and upper watershed, and to begin treatment on sites along the lower Green River.  Large upland infestations on public and privately owned lands may be targeted for control as well.  2005 may also include restoration activities such as native plantings at selected sites depending on site conditions and control results.

Name: Tim Miller

Job Title: Extension Weed Scientist

Agency or Organization: Washington State University

Mailing Address: 16650 State Route 536

Phone: (360) 848-6138

Email: twmiller@wsu.edu

Title of Presentation: Vegetative Reproduction Potential and Herbicide Trial Results  

Summary of Main Points: The speaker will discuss the ability of knotweed to sprout and/or root from stem and rhizome sections and talk about preliminary results from several herbicide trials.

Name: Heather Rogers

Job Title: Invasive Species Control Manager

Agency or Organization: The Nature Conservancy

Mailing Address: 410 North 4th Street Mount Vernon, WA 98273

Phone: (360)419-0556   Email: hrogers@tnc.org

Title of Presentation: Controlling invasive knotweed species in a multi-partner effort on the Skagit River   

  Summary of Main Points:

Effective control of invasive species in large landscapes requires coordinated efforts among landowners, agencies, and property managers.  We describe a partnership among  12 public and private organizations that is rapidly working towards control and eradication of invasive knotweeds (Polygonum cuspidatum, P. sachilensis,P. X bohemicum etc.) in the Upper Skagit watershed. The Skagit Knotweed Working Group (SKWG) was organized in 2001, and is accomplishing this objective by facilitating and coordinating surveys, assessments, and a strategic approach to knotweed treatment activities among private landowners and public agencies, educational outreach, and scientific research. This is important to demonstrate the value of working across ownership boundaries for a landscape scale restoration success.

Survey and control follows a prioritized strategy, focusing first on locating knotweed patches in riparian habitats, where impacts on sensitive native communities are great, and the potential for rapid and widespread dispersal by flood events is considered high. Secondary priorities for control include roadsides, landscaped areas, and around human disturbances. Initial control consists of bending or breaking stems in spring or early summer, followed by a foliar application of the herbicide glyphosate in the fall. At each patch of knotweed measurements of plant size, substrate, proximity to water are recorded and updated after each treatment. Measure of success have been calculated for survey and treatment work for this effort. Fieldwork began in 2002, when over 400 miles were surveyed, 466 patches were mapped, and 209 patches were treated.  Work expanded in 2003, when over 300 miles were resurveyed; 608 patches were located, and 432 treated. One key to sustaining a successful control program has been to have a lead individual to coordinate educational and control efforts, collect and archive data, ensure program continuity, and minimize gaps in control activities. We anticipate that eradication of knotweed should be attainable in the upper watershed within 3 years. Tools developed by the SKWG, including coordination documents, landowner education tools, data collection techniques, and treatment methods, provide a successful system that will be made available for other invasive species watershed working groups to follow.

Name: Jill Silver

Job Title: Watershed Program Manager

Agency or Organization:          10,000 Years Institute

Mailing Address:888 – 53rd Street, Port Townsend, WA 98368-1504

Phone:             360-385-0715

Email:jsilver@10000YearsInstitute.org

Title of Presentation:   Analyzing the Success of the Hoh River Knotweed Control Project: Methods, Assumptions, and Challenges

Summary of Main Points:

In 1998 a clump of knotweed numbering around 100 canes was eroded into the Hoh River at river mile 29.5.  In 2002, four years later, more than 9,600 canes were documented on the extensive active channel floodplain of the Hoh River downstream to the river’s mouth.  The following year, 18,600 canes were treated, beginning a multi-year eradication effort.  We developed an efficient plant tracking system using a geographic positioning system (GPS) with an associated data dictionary.  Using geographic information system (GIS), these data provide valuable information on plant migration, development, and treatment effectiveness.  We tracked treatment effectiveness, and conducted further treatments in 2004.  During the course of the project, a number of research questions relevant to knotweed control were generated about the life history of knotweed.

Name: Laurel Shiner

Job Title: Coordinator

Agency or Organization:  Whatcom County Noxious weed Board

Mailing Address:  901 W. Smith Rd., Bellingham WA 98226

Phone:  360 354-3990  Email: LShiner@co.wacom.wa.us

Title of Presentation: Efforts of the Nooksack Basin Knotweed Working Group

Summary of Main Points:

I will give a brief summary of the formation of our working group, our funding sources, the work that has occurred in 2003 and 2004, and what plans are in the works for 2005.

Name: Gary K. Smith

Job Title: PNW Region Invasive Plants Program Manager

Agency or Organization:  USDA-Forest Service

Mailing Address:  PO Box 3623, Portland, OR  97208-3623

Phone:  503-808-2914  Email: gsmith03@fs.fed.us

Title of Presentation: Forest Service Grants for Cooperative Weed Management on Non-federal Forest Lands

Summary of Main Points:

The Forest Service has had an ongoing management program for invasive plant prevention, control and restoration on National Forest (federal) lands for over a decade.  Starting in 2002 the Forest Service State and Private Forestry Division has provided funding for invasive plant management on non-federal forest lands.  In 2004, the PNW Region received for the first time a total of $ 450,000 of these funds to award to state and local cooperative groups for weed management proposals.  Five grants were awarded to Washington organizations and four to Oregon organizations.  Comparable funding is anticipated for 2005, and we hope to sponsor more organizations in future years.  My talk will summarize current grants, and the requirements for being a successful grantee.

Name:  Jonathan Soll

Job Title:  Portland Area Preserves Manager

Agency or Organization:  The Nature Conservancy

Mailing Address:  821 SE 14^th Ave, Portland, OR, 97214

Phone:  503-230-1221 x129

Email:  jsoll@tnc.org

Title of Presentation:  Control of Japanese knotweed using stem injection

 Summary of Main Points:

Because Japanese and giant knotweed (Polygonum cuspidatum and P. sachalinense respectively) are capable of forming dense monocultures and permanently displacing native species in riparian and flood plain habitats, they represent a major threat to the function of riparian areas and floodplains throughout the Pacific Northwest.  Since 2000, The Nature Conservancy (TNC) has been conducting knotweed control experiments and has engaged in a landscape-level control project in the Sandy River watershed.  Earlier TNC studies focused on testing manual treatment and a variety of foliar and cut-stem type herbicide applications.  Although several treatment combinations provided significant levels of control, each required multiple years to achieve eradication.  Here, we present the 1^st year results of a controlled experiment and associated uncontrolled landscape scale control program testing direct stem injection of the herbicide glyphosate done in partnership with Metro’s knotweed control program on the Clackamas River.  We injected knotweed stems with different volumes of glyphosate in July or September 2003 (1.5, 3 or 5 ml of herbicide concentrate with or without supplemental foliar spray, n = 6) and measured stem number reduction of each patch in summer 2004.  Stem injection provided approximately 90% control, with surviving canes much reduced in vigor.  Glyphosate volume, supplemental spraying, and application timing and the percentage of stems injected had only minor effects.  Data from the landscape scale treatment program largely confirms the results of the small scale experiment.  One year after treatment there is no apparent difference between patches treated with 3ml versus 5ml of herbicide.

Name: Lauren Urgenson

Job Title: graduate student

Agency or Organization: University of Washington

Mailing Address: 5547 Wallingford Ave. N. Seattle, WA 98103

Phone: 206-685-7494 Email: lsu@u.washington.edu

Title of Presentation:

Ecological Consequences of Knotweed Invasion in Riparian Areas

The allocation of resources for the management of Japanese, bohemian and giant knotweed is based on anecdotal evidence suggesting that these species dramatically alter native communities and ecological processes.  Currently, quantitative evidence on the impacts on knotweed invasion is limited.  My research focuses on the effects of knotweed invasion into riparian areas.  By displacing native vegetation, knotweed is suspected to simplify the structural and taxonomic composition of riparian forests and potentially impair the habitat quality of adjacent streams.

This first year of research focused on Grandy Creek, a tributary of the Skagit River invaded by giant knotweed.  Four main questions are being investigated: 1) Does knotweed invasion alter the vegetation composition and diversity of riparian forests? 2) Does knotweed invasion inhibit the regeneration of native tree species? 3) What is the effect of knotweed invasion on the annual quantity, quality, and timing of leaf litter inputs into streams? 3) How does the decomposition and invertebrate colonization of knotweed leaf litter compare to that of a diversity of native species? Data from this study will form the basis of future experiments to further elucidate the ecological impacts of knotweed on riparian forests and stream food webs.

Name: Peter Zika

Job Title: Consultant

Agency or Organization: Herbarium, and Burke Museum, U of W

Mailing Address:  Box 355325, University of Washington, Seattle, WA  98195-5325

Email: Zikap@aol.com 

Title of Presentation: Identification of knotweeds in western Washington

Summary of Main Points: Two species of knotweed (Polygonum cuspidatum and P. sachalinense) occasionally escape from cultivation in western Washington. Their identification is often confused because their hybrid is also cultivated and commonly escapes.  The three taxa can be separated by examining the middle of fertile branches, for the shape of the leaf, the type of leaf tip, the hairs of the leaf underside, and by the sex of the flowers.  Another useful feature is the height of the plant, and the length of the inflorescence relative to the length of the leaf.  Caveats will be explained and illustrated, and material will be on hand to practice with.  Attendees are invited to bring a hand lens and pressed or fresh material of unidentified knotweeds from their favorite weed patch.