Rushes (Juncus, Luzula)

By Bruce Homer-Smith

Rushes are round

Rushes look similar to sedges but have some differences:

· Rushes have round stems. Sedges mostly have triangular stems.

· Rushes have 6-parted flowers. Sedges never do.

· Rushes like water but can grow in a variety of conditions. Sedges like to keep their feet wet.

Pacific Rush (Juncus effusus ssp. pacificus)

Photo by Alf Fengler

Forked Wood Rush (Luzula divaricata)

Photo © Neal Kramer

Rushes look similar to grasses but have some differences:

· Rushes have round stems filled with pith. Grasses have round stems that are hollow. Grasses have “knobby knees” along their length to support their lighter stem arrangement. Rushes don’t.

· Rushes have 6-part flowers. Grasses never do.

· Rushes are most often found in cool areas near water. Grasses do well in a wide variety of habitats, especially dry, open places.

Flowers

Rushes have tiny, six-part flowers, made up of two whorls of three, thin, papery tepals. 3-part stigmas rise from the center of the flower. Most flowers start green and turn brown at maturity, but they can also be white, black or translucent.

Flower clusters form at the top of the stem, but sometimes look like they’re on the side because a stem-like bract continues above the flowers.

Duran’s Rush (Juncus duranii)

Photo by Keir Morse

Baltic Rush (Juncus balticus ssp. ater)

Photo by Wilde Legard

Brewer’s Rush (Juncus brewerii)

Photo by Steve Matson

Baltic Rush (Juncus balticus ssp. ater)

Photo by Steve Matson

These flower photos are magnified. In the real world you’ll have to look closely to find the six-part flowers but when you do, you’ll know you have a rush.

Leaves

Leaves are evergreen and start from the base of the plant. They can be flat or cylindrical, or just reduced to sheaths with no blade.

Brown Headed Rush

Juncus phaeocephalus var. phaeocephalus

Photo by Dee Himes

Iris Leaved Rush

Juncus xiphioides

Photo by Wilde Legard

Common Bog Rush

Juncus effusus

Photo by Amadej Trnkoczy

Mariposa Rush

Juncus dubius

Photo by Keir Morse

Wood Rush (Luzula comosa)

Photo by Barry Breckling

Donner Wood Rush (Luzula subcongesta)

Photo by Steve Matson

The final two photos are of genus Luzula rather than Juncus. The distinguishing feature for Luzula is flat leaf blades with long hairs.

Other

Genus Juncus is generally found in wetland areas. Luzula is more likely to be found in dry areas. There are five other genera in the Rush Family (Juncaceae), but they’re not found in California.

Rushes compete best in infertile soil. They’re perennial and spread through underground rhizomes as well as by seed.

Want More?

Here’s a Genus Key to common California Sedges and Rushes

Corrections/Comments: bruce@PlantID.net