Washington Weed Free Hay and Mulch Program (WWHAM)


The WWHAM program is now run by the Washington State Department of Agriculture's (WSDA) Plant Services Program. You can find out current program information on their website, contact them by email at PlantServices@agr.wa.gov, or call (360) 902-1874.

Program History and Frequently Asked Questions:

Prior to 2011, the Washington State Noxious Weed Board ran the WWHAM program. This webpage contains background information on the program. Please refer to the WSDA's Plant Services Program website for current WWHAM program information.

Why is there a weed-free hay and mulch program?

Invasive plants can be introduced to wilderness via non-certified hay, mulch, straw, and raw feeds. Invasive plants outcompete native plants, degrade wildlife habitat, and reduce soil and water quality. They cause economic losses in natural areas and impact aesthetics and recreation opportunities.

While weeds can be extremely difficult to remove once established in croplands, rangeland, yards, and abandoned lots, they are especially hard to detect and then eradicate in wilderness areas.

The USDA Forest Service passed order 36 CFR 261.58(t) to help prevent the introduction of new weed seeds into designated wilderness areas and all Forest Service lands. Effective January 1, 2009, commercially processed feed pellets and/or certified weed-free straw and feed are now required for all U.S. Forest Service lands in Pacific Northwest National Forests, managed by the USDA Forest Service.

What is guaranteed by WWHAM Certification?

  • It permits entry of the certified products into USFS land throughout the U.S.
  • In other states, some jurisdictions have custom rules that need to be observed. Always contact the State Department of Agriculture for the state where you plan to travel to confirm which states allow WWHAM product. 

Please note - WWHAM products are for domestic use only and WWHAM certification will not qualify a commodity for export from the United States. It provides assurance that the field was inspected based upon a reasonable and prudent visual inspection, and no noxious weeds were detected.

What is NOT guaranteed by WWHAM Certification?

  • It does not guarantee a complete absence of noxious weeds. It only certifies that the inspector made a reasonable and prudent visual inspection and did not find any.
  • It does not certify quality, protein content, maturity, etc.
  • The inspector may note on the inspection certificate factors such as other weeds but certification is only for noxious weeds.

What kinds of products are included in this weed-free requirement?

Hay, hay cubes, straw, grain, and other crop or mulch products must be certified weed-free using standards of the North American Invasive Species Management Association (NAISMA) formerly known as the North American Weed Management Association (NAWMA), regardless of how they are used (livestock feed, erosion control, mulch, etc.).

Please note: Commercially processed feed pellets and steamed, rolled grains are considered weed-free feed and do not need additional certification. The processes by which they are made effectively destroy most viable seeds.

How can a grower get his or her crops WWHAM certified?

Please contact the WSDA Plant Services Program at (360) 902-1874 or at PlantServices@agr.wa.gov to find out how to have your crops WWHAM certified.

Are these weed-free products required if someone is passing through National Forests?

No. You can transport non-certified products through National Forest lands, as long as you do not unload or use them while on the designated wilderness areas and nearby trailheads.

Where can I purchase WWHAM-certified hay and mulch?

Download a list of grower's contact information that have produced WWHAM-certified hay and mulch during this growing season on WSDA's website under the heading WWHAM Certified Growers. 

Where can I learn more about WWHAM?

Please contact the WSDA Plant Services Program at (360) 902-1874 or at PlantServices@agr.wa.gov.

Download the official USDA Forest Service question and answer PDF. It contains more detailed information about the new Forest Service efforts to prevent the introduction of noxious weeds.

North American Invasive Species Management Association (NAISMA) Weed Free Gravel Information

Washington State does not have a Weed Free Gravel Program but we do encourage the volunteer use of NAISMA's Weed Free Gravel Standards. Find these standards and forms on NAISMA's website. The North American Invasive Species Management Association was formerly known the the North American Weed Management Association (NAWMA).