Chelan County’s primary objectives for roadside vegetation management are:
Provide for safe travel on County roads.
Preservation of roadway infrastructure with desirable vegetation and stable roadsides.
Compliance with legal regulations concerning control of noxious weeds.
Herbicides are a cost-effective method of maintaining vegetation, and selective use over time require less product to manage vegetation as native grasses and low-growing plants fill in along roadsides.
What herbicides are used in the residual program?
We use two different roadside mixes. We have a Pre-Emergent Bare Ground Program that is applied either in the spring or fall. A Post-Emergent Program is applied throughout the summer to treat the weeds that pop up through the bare-ground application.
Why control noxious weeds?
The County is required by state law to control all listed noxious weeds that occur on the right-of-way (RCW 17.10). The County is also sensitive to the needs and concerns of adjacent landowners, both for controlling the spread of noxious weeds and the need for use of herbicides to control vegetation. All herbicides used by the County are on the State of Washington Vegetation Management Contract. The Washington State Department of Transportation has completed toxicological and risk analysis for all herbicides on the contract and summaries can be accessed on its website. These herbicides have been determined to be the least toxic to mammals, fish and invertebrates.
When does the County spray for noxious weeds?
Control of noxious weeds is performed from about mid-May to mid-September. Selective herbicides are used in non-sensitive areas to promote the establishment of perennial grasses. Non-selective herbicide (Roundup®) is used in sensitive areas as it is one of just a few herbicides that is relatively safe to use near landscaping, orchards and vineyards.
Does the County spray herbicide on all of the right-of-way for noxious weed control?
No. We spot-spray noxious weeds selectively throughout the spring and summer to promote the establishment of perennial grasses.
Is it safe for me to walk my pets after an application has been made?
Yes. It is safe to come into contact with areas after the herbicide has dried. If pets lick their feet after walking through a treated area, it is advisable to rinse their feet with water, although at the rates of application there is little risk to pets or people.
What if I do not want the County to spray herbicide on the right-of-way adjoining my property?
The County has a program in place for landowners to maintain the County right-of-way in lieu of the County applying herbicides. The County will place “Owner Will Maintain” signs (at no expense to the landowner) at the start and stop of your property, to indicate where to stop and resume spraying. Under this agreement, the landowner is responsible to control all noxious weeds, keep vegetation from encroaching onto the asphalt and keep brush and trees back from the right-of-way line of sight and around utilities and signs. Failure to comply with the terms of the agreement will result in the County removing the Owner Will Maintain signs and resuming use of herbicides to control vegetation. If you are interested, call Public Works at 509-667-6415.
Posted: 10/20/2014 11:08 AM
Last Updated: 04/09/2025 03:37 PM
Archive Disclaimer
The information contained on this site is provided as a courtesy of the Chelan County. Where it exists, the "Index.txt" will contain a brief explanation of files contained in this folder
Chelan County makes every effort to ensure the accuracy of the information provided on its web site. However, due to the possibility of transmission errors, HTML browser capabilities, changes made since the last update to the site, etc., neither Chelan County, nor any agency, officer or employee of Chelan County warrants the accuracy, reliability, or timeliness of any information published by this system and shall not be held liable for any losses caused by reliance on the accuracy, reliability, or timeliness of such information. Portions of such information may be incorrect or not current. Any person or entity that relies on any information obtained from this system does so at his or her own risk.
PLEASE NOTE: FTP browsing is no longer supported on the latest browsers, please refer below to acccess our FTP content.
Popular Browsers
Supported
Microsoft Edge
NO
Google Chrome
NO
Safari
NO
Internet Explorer 11
YES
Mozilla Firefox
YES
Opera
YES
By clicking continue, you confirm that you have read, understood and agreed to this disclaimer.
The information contained on this site is provided as a courtesy of the Chelan County. Where it exists, the "Index.txt" will contain a brief explanation of files contained in this folder
Chelan County makes every effort to ensure the accuracy of the information provided on its web site. However, due to the possibility of transmission errors, HTML browser capabilities, changes made since the last update to the site, etc., neither Chelan County, nor any agency, officer or employee of Chelan County warrants the accuracy, reliability, or timeliness of any information published by this system and shall not be held liable for any losses caused by reliance on the accuracy, reliability, or timeliness of such information. Portions of such information may be incorrect or not current. Any person or entity that relies on any information obtained from this system does so at his or her own risk.
PLEASE NOTE: FTP browsing is no longer supported on the latest browsers, please refer below to acccess our FTP content.
Popular Browsers
Supported
Microsoft Edge
NO
Google Chrome
NO
Safari
NO
Internet Explorer 11
YES
Mozilla Firefox
YES
Opera
YES
By clicking continue, you confirm that you have read, understood and agreed to this disclaimer.
The information contained on this site is provided as a courtesy of the Chelan County. Where it exists, the "Index.txt" will contain a brief explanation of files contained in this folder
Chelan County makes every effort to ensure the accuracy of the information provided on its web site. However, due to the possibility of transmission errors, HTML browser capabilities, changes made since the last update to the site, etc., neither Chelan County, nor any agency, officer or employee of Chelan County warrants the accuracy, reliability, or timeliness of any information published by this system and shall not be held liable for any losses caused by reliance on the accuracy, reliability, or timeliness of such information. Portions of such information may be incorrect or not current. Any person or entity that relies on any information obtained from this system does so at his or her own risk.
PLEASE NOTE: FTP browsing is no longer supported on the latest browsers, please refer below to acccess our FTP content.
Popular Browsers
Supported
Microsoft Edge
NO
Google Chrome
NO
Safari
NO
Internet Explorer 11
YES
Mozilla Firefox
YES
Opera
YES
By clicking continue, you confirm that you have read, understood and agreed to this disclaimer.
The information contained on this site is provided as a courtesy of the Chelan County. Where it exists, the "Index.txt" will contain a brief explanation of files contained in this folder
Chelan County makes every effort to ensure the accuracy of the information provided on its web site. However, due to the possibility of transmission errors, HTML browser capabilities, changes made since the last update to the site, etc., neither Chelan County, nor any agency, officer or employee of Chelan County warrants the accuracy, reliability, or timeliness of any information published by this system and shall not be held liable for any losses caused by reliance on the accuracy, reliability, or timeliness of such information. Portions of such information may be incorrect or not current. Any person or entity that relies on any information obtained from this system does so at his or her own risk.
By clicking continue, you confirm that you have read, understood and agreed to this disclaimer.
The information contained on this site is provided as a courtesy of the Chelan County. Where it exists, the "Index.txt" will contain a brief explanation of files contained in this folder
Chelan County makes every effort to ensure the accuracy of the information provided on its web site. However, due to the possibility of transmission errors, HTML browser capabilities, changes made since the last update to the site, etc., neither Chelan County, nor any agency, officer or employee of Chelan County warrants the accuracy, reliability, or timeliness of any information published by this system and shall not be held liable for any losses caused by reliance on the accuracy, reliability, or timeliness of such information. Portions of such information may be incorrect or not current. Any person or entity that relies on any information obtained from this system does so at his or her own risk.
By clicking continue, you confirm that you have read, understood and agreed to this disclaimer.
