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E.D.R.R. - Early Detection Rapid Response
ODA, Noxious Weed Control Program Early Detection and Treatment Activities
invasion curve
Early Detection and Rapid Response (EDRR) are primary activities of the Weed Control Program. Weeds are listed and targeted for early detection and rapid response activities. The goal is to prevent introduction or find them through early detection efforts and implement control measures to prevent widespread occurrence in Oregon. ODA accomplishes this through its noxious weed quarantine and by implementing EDRR projects. A principal activity is using a weed risk assessment process with the OSWB to list species on the State Noxious Weed List. Priority listed species, "A" and "T" designated weeds of limited distribution in the state are the primary EDRR targets for ODA. Priority species are incorporated into presentation and outreach activities to increase awareness. Pest alerts and educational materials are distributed in an effort to find new infestations. Survey for early detection is conducted and when EDRR targets are found rapid response projects are implemented for eradication or containment. ODA staff works with state and federal cooperators, county weed programs, CWMAs, and private landowners to implement EDRR projects or provides assistance through OSWB grants.

An economic analysis reveals a 33:1 benefit to cost ratio for EDRR projects. Annual treatments for the control of “A” (highest priority ) and “T” (target) designated weeds have reduced the net acreage of many large infestations of weeds. For example, annual intensive control efforts for distaff thistle (Carthamus lanatus), and purple starthistle (Centaurea calcitrapa), have achieved 99 percent control.

ODA continues to meet program goals to limit or reduce acreages of all “A” rated weeds and implement projects for “A” and “T” listed species. Statewide management plans for “T” weeds are updated annually to identify priorities for staff. Weed awareness continues to increase with the general public.
The following are a few highlights of “A” and “T” weed projects happening in regions throughout Oregon.
RESOURCE: Western US Invasive Plant EDRR Weed ID Guide
This is a publication provided as a resource to Oregonians to aid in Early Detection and Rapid Response for invasive weeds in Oregon.

Northwest Oregon
Kudzu flower
Kudzu Control
In July 2000, kudzu (Pueraria lobata) was detected on a road bank in Clackamas County. This was the first infestation detected west of Texas. Kudzu is an aggressive climbing vine that trails over and smothers surrounding trees and plants. It is native to China and Japan and is a major problem in the southeastern US where an estimated 7 million acres are infested. A second Oregon site was detected in Multnomah County in 2000, and another in 2001. The sites were treated with a selective herbicide and have required periodic follow-up treatments for control of re-growth. Survey and detection efforts have been conducted throughout western Oregon and no additional sites have been detected. The three known sites were monitored and two required treatment in 2010.

Southwest Oregon
Alyssum photo
Alyssum Control
Yellow tuft, Alyssum murale and A. corsicum, where introduced to the Illinois Valley of southwest Oregon in the 1990s as a crop to extract nickel from serpentine soils. Alyssum has since spread from planted fields and become an invasive weed. The intent of this project is to protect serpentine soil habitat of southwest Oregon from the invasion of this non-native alyssum species. Partners include the USFS, BLM, TNC, and private landowners.

The Illinois Valley contains the largest concentration of serpentine soils in Oregon and supports a diverse and unique flora. Fifteen plant taxa have conservation status in the area. Alyssum murale and A. corsicum are perennials native to Eastern Europe that inhabit serpentine soils. They belong to a group of plants that hyper-accumulate and store heavy metals. The species were studied by USDA and promoted as an environmentally conscious method of cleaning mine spoils for remediation. In the 1990s, studies changed from remediation interests to growing alyssum on naturally occurring nickel rich soils to accumulate and harvest nickel. In the late 1990s Viridian Co., with the assistance of USDA and OSU researchers, planted alyssum fields in Illinois Valley to evaluate its commercial use.

By 2005, alyssum plants were found far from cultivated fields. Federal agencies, TNC, and plant conservationists became skeptical of early assertions of the inability to invade Josephine County’s botanically rich serpentine areas. An interagency task force began documenting escaped populations in 2005. Populations were found on state, USFS, BLM, TNC, and private ownerships in the area. Populations were also found on the floodplain of the West Fork of the Illinois River. After negotiating with Viridian, ODA started implementing a control project in 2009. ODA has surveyed and treated the area for two consecutive years staring in 2009. In 2010, 103.39 net acres where treated over 805.5 gross acres.

North Central Oregon
Purple starthistle flower
Purple and Iberian Starthistle Control
Purple and Iberian starthistle (Centaurea calcitrapa and C. iberica), are two species of limited distribution in Oregon. The species have the potential to invade 1.5 million acres in Oregon with an economic impact of $12 million per year. Prior to the 2009 field season only a single active purple starthistle site was confirmed from Oregon in Clackamas County. Five small historic sites have occurred and all have been eradicated.

The Clackamas County site has been under intensive treatment since 1993, and only an occasional plant is found at the site. In late June of 2009, the Gilliam County weed supervisor found a nine-acre infestation just south of Spray, in Wheeler County. The infestation was treated within days and follow-up survey and treatment were completed in 2010.

The Clackamas County infestation was estimated at 2 net acres over 80 gross acres. No plants were found in 2008, and again in 2010. The last several years of treatment have shown significant drops in plant numbers, indicating that the dormant seed bank may be nearing depletion. Monitored 80 acres, no plants were found.

South Central Oregon
Taurian thistle flower
Taurian Thistle Control
Taurian thistle (Onopordum tauricum) is a sister plant to Scotch thistle (Onopordum acanthium) and has the same potential to be invasive. In Europe, it is a more aggressive then Scotch thistle. Taurian thistle is lime green with large baseball sized terminal flower heads that resemble an artichoke. The leaves feel sticky to the touch, like glue, but leave no residue on the fingers.

The first and only Oregon population was discovered in Klamath County in 2007. California has had several historical sites from Modoc County, Monterey, and a few scattered locations in the southern Sierra Mountains. The only other report in the US is from Pueblo County in Colorado. In 2007, there were 250 large plants and seedlings scattered over 4 gross acres at the Klamath County location. All the plants in the infestation were treated by ODA in 2007, 2008, 2009, and again in 2010. This year ODA only found 17 bolting plants and seven seedlings and rosettes at the site, which were treated.

Northeast Oregon
Orange hawkweed flower
Orange hawkweed was detected by a Wallowa Resources Survey crew on Davis Creek in 2009.  This is the first wild infestation of Orange hawkweed in Northeast Oregon.  ODA confirmed the siting and treated the Orange and Meadow hawkweed in the upper reach  of Davis creek.  The Orange hawkweed was located inside a fairly old Habitat Exclosure,  with very limited access. The entire infestation was a moderate density scattered over 60 meters by 25 meters, flanked by Meadow hawkweed.  The Meadow hawkweed was scattered the length of the creek.  This site has been monitored intensively.

Southeast Oregon
African rue infestation
African Rue Control
African rue (Peganum harmala) is native to North Africa and Asiatic deserts and was first reported in North America in 1928 near Deming, New Mexico. Oregon's first infestation was a mystery. An OSU herbarium specimen was recorded in the mid 1960s from Crook County, but did not mention a specific location. A member of the native plant society located the site in 1991. The site has been treated as an "A" rated weed by ODA and Crook County since the re-discovery. A second infestation was found in Harney County in 2008.

The Crook County infestation is along Highway 27 and occurs on both public and private lands. The main portion of the infestation is on BLM land and provides most of the funding for control. Crook County and ODA are working together to treat the site; in 2010, plants continue to be found in the known control area. The roadways leading into and out of the control area and the surrounding rangeland are surveyed yearly. No new plants were found outside of the historic treatment area. Less than 10 plants were found over the 500 gross acre site.

In 2008, an African rue infestation was found on tribal allotments located in the Harney Basin southeast of Burns. The initial response was to treat outlier sites, roadsides, barnyards, and pivots for containment and to prevent further spread. In 2008, ODA staff spent several weeks doing the initial site delimitation, which revealed a project area of 2,700 gross acres and 19 landowners including Department of State Lands, private, and tribal lands. An African Rue Cooperative Weed Management Plan was completed in 2009. There were 200 net acres treated in 2009.

In 2010, the project began with an assessment of the efficacy of last year's herbicide applications including a review of preliminary research results from OSU. After looking at multiple sites and comparing photo point information, it was decided that last year's application of Milestone + Escort XP was not providing adequate control in a broadcast situation. Areas that were treated by handgun with the Milestone + Escort XP mix had 100 percent control with no re-growth. After discussing the results with cooperators and reviewing published research, it was decided to change the herbicide products and mixes for the 2010 broadcast applications. A total of 128 acres were treated in 2010 with no new sites found.