Spartina densiflora

Spartina densiflora_dense-flowered cordgrass_JM DiTomaso_cropped
Photo: Joseph DiTomaso

Common names: dense-flowered cordgrass; Chilean cordgrass.

Spartina densiflora (dense-flowered cordgrass) is a rhizomatous perennial grass (family Poaceae) found in salt marshes in Humboldt Bay and San Francisco Bay. Dense-flowered cordgrass may have been introduced to Humboldt Bay from Chile by lumber ships in the 19th century. It tolerates high salinity and grows especially well in higher tidal marsh, where it is known to displace native pickleweed (Salicornia pacifica) and native California cordgrass (Spartina foliosa). The species’ abundant seed has the potential to disperse over long distances by floating on water.

Cal-IPC Rating: High?

CDFA Rating: -*?


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.

Weed Management Notes

  • Management Notes - Information on management techniques and effectiveness from the University of California Cooperative Extension’s Weed Research & Information Center.

Cal-IPC Newsletter Articles

Cal-IPC Symposium Presentations

Presentations are linked where available. Where a presentation is not available, find more information by reading the abstract in the Cal-IPC Symposia Archive.

Other Spartina densiflora Information

  • CalPhotos - Images of plants taken mostly in California.
  • Calflora - Distribution map and records of this species in California.
  • CalWeedMapper - Distribution map of this species in California with ability to determine regional priorities.
  • EDDMapS - Distribution of this species in North America.
  • Jepson Interchange - Information on this plant's taxonomy, biology, and distribution from UC Berkeley's Jepson Herbarium.
  • USDA PLANTS Database - Information on identification and distribution, with links to websites in individual states.
  • Additional photos

    Spartina densiflora_inflorescence_JoeDiTomaso
    Spartina densiflora (dense-flowered cordgrass) inflorescence. Photo: Joe DiTomaso
    Spartina densiflora_leaf base and sheath_JoeDiTomaso
    Spartina densiflora (dense-flowered cordgrass) leaf base and sheath. Photo: Joe DiTomaso