The 10 worst weeds

  • Reported by Alejandro Dominguez
  • Thursday, June 2, 2011 12:01am
  • Local News

Noxious weeds are invasive plants that change the environment by pushing out species naturally found here. In 2010, Snohomish County had a budget of about $250,000 to kill or control the spread of noxious weeds. Here are the top 10 noxious weeds in Snohomish County. [Gallery]

There are about 100 species of noxious plants that should be eradicated, according to the Snohomish County Noxious Weed Control Board. Some arrived as plants sold for gardens or landscapes. Of those on the control board’s list, 34 are confirmed to be in Snohomish County.

Weed control: For more information on noxious weeds, you can contact the Snohomish County Noxious Weed Control Board at 360-435-7830 or 800-562-4367. The control board is at 26718B 115th Ave. NE, Arlington. Its website is here.

Other useful sites:
• Washington State Noxious Weed Control Board
• King County’s noxious weed site (more detailed than Snohomish County’s)
• WSU Master Gardener’s noxious weeds information

To learn more about the plants listed as noxious weeds in Washington state, click here to go to the USDA’s site.


Knotweed: This shrub-like perennial looks like bamboo and can grow up to 10 feet tall. It causes problems in river ecosystems, such as that along the Skykomish, because it affects water temperature, which threatens salmon redds, or nests of eggs. Herbicides only work on this resilient weed in the fall when it tries to produce seeds. The county received a grant to fight it. [Gallery]

Hawkweed: The most widespread are the yellow and orange hawkweed: They have small, bristly hairs that cover the stems, leaves and flower buds. They are mostly found along walking trails and side roads, especially in Granite Falls near the Mount Loop Highway. The county is waiting for a grant to help pay for controlling it. [Gallery]

Purple loosestrife: Known as “the wetland killer,” this small plant clogs irrigation canals and drainage ditches. It has purple to magenta flowers with five to six petals. A visible nest of it is underneath the U.S. 2 trestle in Everett. Every year, the county releases a non-native beetle that only eats this plant. Herbicides can only be used with a permit if the weed is near water. [Gallery]

Tansy ragwort: This 13-petal, daisy-like flowering plant is often found in empty fields, unkempt grounds and even where horses roam. It causes liver damage in livestock that eat it. It’s abundant in Clearview and Maltby. The county only focuses on this plant along roads. [Gallery]

Canada thistle: The small purple-pinkish flower is so widespread that the county can only act when someone reports it to the department. Containment has fallen mostly to homeowners. Herbicides can be effective. [Gallery]

Giant hogweed: The 15-foot plant has been used in landscaping in the past. When exposed to sunlight, its sap can cause second-degree burns on human skin. The plant has been contained to 15 private sites in the county. Call the noxious weed control board if you find one. Round-up is effective. [Gallery]

Poison hemlock: This aromatic plant is found mostly in Stanwood and the lower part of Snohomish. Its most distinguishing feature is a smooth stem with purple splotches. All of the plant is toxic for livestock and humans. Wear gloves to dig it out. Bag the seeds and flowers and throw them into the trash. [Gallery]

Diffuse knapweed: This flower with purple or white petals colonizes everything in its way. If it’s found in your garden, mowing it is not recommended. The weeds must be pulled early before they go to seed. [Gallery]

Butterfly bush: This shrub can have up to 15-foot branches and 10-inch bell-shaped pink flowers. A landscaping plant, it has spread in river corridors and urban areas. The best way to get rid of it is to cut the flowers off and pull it out. [Gallery]

English ivy: You can tell this ivy by its heart-shaped leaf. It’s found throughout the county and climbs over large trees, making them heavier and more prone to fall from strong winds. To eradicate, the vines must be pulled from the roots. [Gallery]

Talk to us

> Give us your news tips.

> Send us a letter to the editor.

> More Herald contact information.

More in Local News

Trader Joe’s customers walk in and out of the store on Monday, Nov. 20, 2023 in Everett, Washington. (Olivia Vanni / The Herald)
New Trader Joe’s opens this week at Everett Mall

It’s a short move from a longtime location, essentially across the street, where parking was often an adventure.

Ian Bramel-Allen enters a guilty plea to second-degree murder during a plea and sentencing hearing on Wednesday, March 6, 2024, at Snohomish County Superior Court in Everett, Washington. (Ryan Berry / The Herald)
‘Deep remorse’: Man gets 17 years for friend’s fatal stabbing in Edmonds

Ian Bramel-Allen, 44, pleaded guilty Wednesday to second-degree murder for killing Bret Northcutt last year at a WinCo.

Firefighters respond to a small RV and a motorhome fire on Tuesday afternoon in Marysville. (Provided by Snohomish County Fire Distrct 22)
1 injured after RV fire, explosion near Marysville

The cause of the fire in the 11600 block of 81st Avenue NE had not been determined, fire officials said.

Ashton Dedmon appears in court during his sentencing hearing on Tuesday, March 5, 2024, at Snohomish County Superior Court in Everett, Washington. (Ryan Berry / The Herald)
Everett Navy sailor sentenced to 90 days for fatal hit and run

Ashton Dedmon crashed into Joshua Kollman and drove away. Dedmon, a petty officer on the USS Kidd, reported he had a panic attack.

A kindergarten student works on a computer at Emerson Elementary School on Wednesday, Feb. 28, 2024, in Everett, Washington. (Ryan Berry / The Herald)
‘¡Una erupción!’: Dual language programs expanding to 10 local schools

A new bill aims to support 10 new programs each year statewide. In Snohomish County, most follow a 90-10 model of Spanish and English.

Cassie Franklin, Mayor of Everett, delivers the annual state of the city address Thursday morning in the Edward D. Hansen Conference Center in Everett, Washington on March 31, 2022.  (Kevin Clark / The Herald)
At Everett mayor’s keynote speech: $35 entry, Boeing sponsorship

The city won’t make any money from the event, city spokesperson Simone Tarver said. Still, it’s part of a trend making open government advocates wary.

Logo for news use featuring the Tulalip Indian Reservation in Snohomish County, Washington. 220118
Woman drives off cliff, dies on Tulalip Reservation

The woman fell 70 to 80 feet after driving off Priest Point Drive NW on Sunday afternoon.

Everett
Boy, 4, survives fall from Everett fourth-story apartment window

The child was being treated at Seattle Children’s. The city has a limited supply of window stops for low-income residents.

People head out to the water at low tide during an unseasonably warm day on Saturday, March 16, 2024, at Lighthouse Park in Mukilteo, Washington. (Ryan Berry / The Herald)
Everett shatters record high temperature by 11 degrees

On Saturday, it hit 73 degrees, breaking the previous record of 62 set in 2007.

Snohomish County Fire District #4 and Snohomish Regional Fire & Rescue respond to a motor vehicle collision for a car and pole. The driver was pronounced dead at the scene, near Triangle Bait & Tackle in Snohomish. (Snohomish County Sheriff’s Office)
Police: Troopers tried to stop driver before deadly crash in Snohomish

The man, 31, was driving at “a high rate of speed” when he crashed into a traffic light pole and died, investigators said.

Alan Dean, who is accused of the 1993 strangulation murder of 15-year-old Bothell girl Melissa Lee, appears in court during opening statements of his trial on Monday, March 18, 2024, at Snohomish County Superior Court in Everett, Washington. (Ryan Berry / The Herald)
31 years later, trial opens in Bothell teen’s brutal killing

In April 1993, Melissa Lee’s body was found below Edgewater Creek Bridge. It would take 27 years to arrest Alan Dean in her death.

Logo for news use featuring the municipality of Snohomish in Snohomish County, Washington. 220118
Man dies after crashing into pole in Snohomish

Just before 1 a.m., the driver crashed into a traffic light pole at the intersection of 2nd Street and Maple Avenue.

Support local journalism

If you value local news, make a gift now to support the trusted journalism you get in The Daily Herald. Donations processed in this system are not tax deductible.