Blog by Nancy Forrest
Recently, we moved our boat up to the Delta for the summer. Normally, it’s in Benicia, which is closer to the San Francisco Bay. The Delta is a labyrinth of sloughs where vine-covered trees, blackberry brambles, and tule grasses appear at almost every turn. It is a boater’s paradise and also a boater’s nightmare as it is home to some of the most invasive species (Water Hyacinth and Brazilian Waterweed), which threaten the ecosystem by displacing native plants. Continued warm temperatures help the plants multiply at high rates. These plants are also known to form dense mats of vegetation, creating safety hazards for boaters and marinas, so much so that this year the California State Parks’ Division of Boating and Waterways is beginning its herbicide treatments to control these invasive aquatic plants in the Delta[1].
Just a little something about these plants, the Water Hyacinth (Eichhornia crassipes) can grow to cover 6,500 square feet of open water in a single growing season. It was introduced to Delta in the 1940s by an avid water gardener. It has beautiful, showy purple flowers and is easy to grow.
The Brazilian Waterweed (Egeria densa) can root in as much as seven feet of water, and forms thick, ropy mats that can foul propellers and pumps, posing a management hazard for marinas and ports. It is a result of someone emptying aquarium water into the waterways of the Delta.
