Zostera japonica has thinner blades than our native eelgrass.

WILLAPA BAY — The Washington Department of Ecology last week announced a public comment period, an online workshop and a hearing in South Bend concerning ongoing efforts to limit the amount of invasive Zostera japonica eelgrass in the bay’s commercial clam beds.

While eelgrass is generally considered a beneficial part of aquatic and esturine habitats, the Japanese form of the plant is classified as a Class C noxious weed, the lowest category of noxious weed, that are generally present over a large area in Washington.

It interferes with the productivity and usefulness of Willapa’s commercially valuable clam beds. After a lengthy debate and regulatory process, a permit to spray the non-native eelgrass was first issued in 2014.

“This permit to control Zostera japonica using an aquatic herbicide is very limited, it is only for commercial clam growers in Willapa Bay and it does not apply to geoduck or oyster beds,” ecology said in a press release.

Only one herbicide is allowed under the permit, imazamox. Registered by EPA for aquatic uses, EPA categorizes this herbicide as a reduced-risk pesticide (their lowest toxicity category), meaning any amount of imazamox found in or on food products is not considered a human health risk. Imazamox is only toxic to plants and is considered practically non-toxic to animals, fish, invertebrates and other non-plant aquatic species.

Ecology generally updates and reissues herbicide permits every five years and it is now time for the agency to update the Zostera japonica permit.

No significant changes are planned in the permit. Comments on updating this permit will be accepted until 11:59 p.m. on Nov. 4.

Copies of a draft permit and fact sheet are available at https://tinyurl.com/Eelgrass-Info. These documents may also be obtained from Jon Jennings, at jonathan.jennings@ecy.wa.gov, or 360-407- 6283.

Comments may be made online via an eComment form (see link at the web address provided above), or by mail to Jon Jennings, WA State Department of Ecology, P.O. Box 47696, Olympia, WA 98504- 7696.

An online workshop is planned Oct. 21 starting at 1 p.m., with registration available at https://tinyurl.com/Eelgrass-Workshop. An in-person hearing is planned Oct. 22 starting at 1 p.m. at the Willapa Harbor Community Center, 916 W First Street, South Bend.