Herbicide treatment for water hyacinth to begin in Delta

SACRAMENTO — California Department of Parks and Recreation Division of Boating and Waterways (DBW) will begin using herbicide treatment on Wednesday, March 1 of several invasive aquatic plant species that have invaded the Delta. Those plants include the South American spongeplant, Uruguay water primrose, water hyacinth, curlyleaf pondweed and Brazilian waterweed.

The herbicide treatment will begin in waterways south of highway 12 on March 4 and will continue through Nov. 30 for Water Hyacinth and Spongeplant. Areas north of highway 12 will be treated from June 1 to Nov. 30. The other invasive plants that grow underwater will be treated in areas identified in surveys. Mechanical harvesting of the invasive plants will continue throughout the year.

The areas will be monitored weekly to ensure that the herbicides don’t adversely affect the environment, public health and local agriculture.

Because these invasive plants encounter no known natural controls in the Delta, the DBW is working to control the spread and growth of these plants, according to the DBW. It is likely that the plants will never be eradicated from the Delta, they said.

“The good news is that this spring we received a little assistance from Mother Nature in terms of a deep frost and increased water runoff helping to flush the plants out to the ocean,” said DBW’s Deputy Director Lynn Sadler. “Plus, we have more boats and more staff. Best of all we have local, state and federal partners who are helping us manage this challenge.”