Glyceria declinata

Photo courtesy Joseph DiTomaso

Common names: mannagrass; sweetgrass; waxy mannagrass

Glyceria declinata (waxy mannagrass) is a perennial grass (family Poaceae). Waxy mannagrass is found in the Central Valley, from Shasta County south to Fresno County. It has invaded deep vernal pools, swales, ditches, and stock ponds. Some reports indicate that it is rapidly spreading in Central Valley vernal pools.

Rating: Moderate

Cal-IPC Resources

  • Plant Assessment Form - Information gathered by Cal-IPC on the impacts, rate of spread, and distribution of invasive plants in California. Does not include management information.
  • CalWeedMapper - Statewide maps, climate models, and reports.
  • Cal-IPC News - Our quarterly newsletter. Each issue is available as a pdf.
  • Cal-IPC Symposium Proceedings - Presentations and papers from our annual Symposium.
  • Don't Plant a Pest! - Select your region to find non-invasive alternatives to ornamental species. Also see our statewide brochure on trees.

    Other Resources

    Symposium Presentations

    Cal-IPC News Articles

    • None for this species.
    • Cal- IPC Symposium Proceedings