News.bytes News.bytes Extra, issue 240

Winning latest Cosumnes battle against water hyacinth

Managers at the Cosumnes River Preserve have declared victory in the latest battle against water hyacinth. A half-mile stretch of Lost Slough was cleared of the invasive weed. An excavator removed most of the weed in early July. Volunteers removed another 70 canoe loads of weeds the excavator couldn't reach.

Volunteers unload water hyacinth after gathering it in a canoe:
Volunteers unload water hyacinth after gathering it in a canoe

Water hyacinth (Eichhornia crassipes) showed up in California more than 100 years ago. The water hyacinth is an attractive plant, with shiny green leaves and delicate lavender flowers. However, this extremely prolific aquatic weed can quickly spread into a dense floating mat of vegetation. It has become a recurring problem in the Cosumnes River Preserve , managed by BLM California. If allowed to spread, the area covered by water hyacinth will double in 18 days. “It spreads over the surface of the water, blocking sunlight from penetrating the water and preventing photosynthesis,” said Preserve Wetlands Manager Holden Brink. The decaying biomass also effectively cuts off oxygen to any organism in the water.

“It takes a lot of hard work to physically remove the plant from areas it is choking off, but it is the best alternative to spraying, especially in confined areas and where dying plants can clog pumps or other equipment,” he said.

Physically removing the plant takes tools and hard work:
Physically removing the plant takes tools and hard work

The preserve is home to California's largest remaining valley oak riparian forest, and is one of the few protected wetland habitat areas in the state. The Cosumnes River is the only free-flowing river left in California's Central Valley. Only minutes from California's capital, this is a critical stop on the Pacific Flyway for migrating and wintering waterfowl. Over 200 species of birds have been sighted on or near the preserve, including the state-listed threatened Swainson hawk, greater and lesser sandhill cranes, Canada geese and numerous ducks. The preserve includes 40,000 acres of central valley grasslands, vernal pools, wetlands and valley oak forests.

BLM wildlife biologist Peggy Cranston holds one of the enemy:
BLM wildlife biologist Peggy Cranston holds one of the water hyacinths

The preserve land-owning partners working cooperatively are: Bureau of Land Management - Folsom Field Office; California Department of Fish and Game; Ducks Unlimited, Inc.; California Department of Water Resources; Sacramento Co. Dept. of Regional Parks, Open Space, and Recreation; The Nature Conservancy; Wildlife Conservation Board; Natural Resource Conservation Service, and California State Lands Commission.

A work team takes a break for a quick photo: (from left) Mark Ackerman, BLM CRP Wildlife Biologist; Diane Wilson, volunteer; David Christy, BLM Central California Public Affairs Officer; Rod Hall, volunteer; Peggy Cranston, BLM wildlife biologist

- 7/17/06
D. Christie

BLM California News.bytes, issue 240