Drooping sedge (Carex pendula)

Gallery:

Common names:

drooping sedge, hanging sedge

Scientific Name:

Carex pendula

Description:

Carex pendula is an exotic, clump-forming sedge. It grows in full to partial shade in moist soils and has long and drooping inflorescences. Please see below for additional identification resources as there are similar native species.

Life cycle:

Perennial

Height of mature plants

3-6 feet

Flower color:

Inconspicuous off-white flowers

Bloom time:

March through May

Look-a-likes:

There are several species present in our area that look similar to Carex pendula. Carex pendula belongs to a group of grass-like plants called sedges which, in general, are difficult to identify. Therefore, caution is advised when not experienced with this group of plants. After using this simplified resource, please consult an experienced Carex indentifier or technical manual such as the Flora of Oregon: Volume 1 or Field Guide to Sedges of the Pacific Northwest to confirm your identification. Also check out our plant identification resources.

Four key features need to be present to confirm your identification: dense tufts or clumped (cespitose) growth form, large plant size (culms and leaves), wide leaf blades, and long & drooping spikes. There are several species that have at least two of these characteristics including Carex amplifolia, Carex aquatilis var. dives, Carex cusickii, Carex obnupta, Carex hendersonii, Carex utriculata, and Scirpus microcarpus. Please review the below image gallery and chart that dissects each of these features and how Carex pendula compares with each look-a-like species. Species traits taken from Flora of Oregon: Volume 1 and field observations.

Cespitose growth Plant height Wide leaf Long & drooping spikes
  • Carex pendula
  • Carex cusickii
  • Carex hendersonii
  • Carex pendula
    • culms 100-200 cm
  • Carex amplifolia
    • culms 50-100(130) cm
  • Carex aquatilis var. dives
    • culms 35-150 cm
  • Carex cusickii
    • culms 30-200 cm
  • Carex obnupta
    • culms 20-120(200) cm
  • Carex utriculata
    • culms 25-120 cm
  • Scirpus microcarpus
    • leaves 23-60(75) cm
  • Carex pendula
    • 8-20+ mm
  • Carex amplifolia
    • 8-20 mm
  • Carex aquatilis var. dives
    • 5-18 mm
  • Carex hendersonii
    • 3-16 mm wide
  • Carex utriculata
    • 4.5-12 mm
  • Scirpus microcarpus
    • 5-15(20) mm
  • Carex pendula
    • 10-30+ cm long
    • drooping & flexible
  • Carex aquatilis var. dives
    • 4.5-11.5 cm
    • drooping
  • Carex obnupta
    • 2.5-15 cm long
    • erect to drooping
  • Rhizomatous
    • Carex amplifolia
    • Carex aquatilis var. dives
    • Carex obnupta
    • Carex utriculata
    • Scirpus microcarpus 
  • Carex hendersonii
    • culms 45-90 cm
  • Carex cusickii
    • 2.5-5 mm
  • Carex obnupta
    • 3-7 mm
  • Carex amplifolia
    • (1.5)3.5-14 cm
    • ascending to spreading
  • Carex cusickii 
    • 3-8 cm
    • nodding
  • Carex hendersonii
    • 1.2-4 cm
    • erect to ascending
  • Carex utriculata
    • 2-10 cm
    • erect to ascending
  • Scirpus microcarpus
    • very different with dense clusters of 3-18 spikes

Habitat:

C. pendula is known to affect wetlands, streamsides, roadsides, and adjacent forested habitats in Oregon.

Impacts:

Carex pendula has been observed in Clackamas County displacing native species along streams where in some cases it formed stands of 85% dominance. Assessing the distribution, impacts and potential impacts of this species requires more work and is a current project of the District.

Noxious Weed Listing:

Origin:

Europe, North Africa

Links:

Invasive.org profile
CABI Invasive Species Compendium
USDA APHIS Weed Risk Assessment for Carex pendula

 

WeedWise Program