Environ. Horticulture, Pears, Cherries, and Viticulture
University of California
Environ. Horticulture, Pears, Cherries, and Viticulture

Sedge

Dune sedge, Carex pansa, (KARE-ex PAN-sa)

Field sedge, Carex praegracilis, (KARE-ex pree-GRASS-il-is)

Sedge is not a grass, but several species can be used to create an excellent turf. They are very drought tolerant and can be mowed periodically or left unmowed. They can also be used in the landscape, but they can be a bit invasive if not given enough space.

C. praegracilis, mowed and non-mowed (Photo- David Fross)
C. praegracilis, mowed and non-mowed (Photo- David Fross)

C. praegracilis, not enough room (Photo- Elizabeth Wise)
C. praegracilis, not enough room (Photo- Elizabeth Wise)

Carex lawns are difficult to sow by seed since germination rates can be highly variable, so they are generally planted by plugs or 2 1/4" pots (liners). They spread by short rhizomes that spread relatively slowly, so they should be planted no farther than 9 in. apart for turf. Planting even closer would shorten the time to complete establishment and reduce weed growth, but is much more expensive and time consuming to plant.

C. pansa (left), C. praegracilis (right) (Photo- David Amme)
C. pansa (left), C. praegracilis (right) (Photo- David Amme)
Several Carex species will work as turf, but Carex praegracilis (field sedge) and Carex pansa (dune sedge) are probably the most prevalent, and they are most likely to tolerate the intense heat of California's Central Valley.

The two species have been thought of as very similar, and there has been debate about whether there really is a difference since there is huge variability among local populations from where they are collected in the wild. However, most C. praegracilis populations are generally taller than C. pansa, and C. praegracilis is the species most used in the turf trade.

 

Pat Schink planting Carex, 9/20/10
Pat Schink planting Carex, 9/20/10
In our demonstration, we planted Carex in 3 plots, and each plot is split between the two species. 2 1/4-inch liners were planted 9 in. apart on September 20, 2010.

Growth was fairly slow in fall and winter, and by May 2011 they were spreading non-uniformly. UC Verde buffalograss fills in much more quickly when planted no earlier than May.

Carex plug (center) with weeds all around
Carex plug (center) with weeds all around

 

 

 

 

Both grass and broadleaf weeds were a major problem initially, and we thoroughly hand-weeded 4 times through May 2011. We didn't use pre- or post-emergent herbicides, but they certainly would be useful in a larger planting.

We are using only organic products and methods on the plots. A thicker layer of fine mulch would have also helped.

 

C. praegracilis (right) tended to have more rust disease in winter than C. pansa (left)
C. praegracilis (right) tended to have more rust disease in winter than C. pansa (left)

 

 

  

Rust has been known to attack Carex, and in the wet winter of 2010-11, rust seemed to be worst on the C. praegracilis (right), and less on C. pansa.

 

 

 

 

 

 

 

 

 

 

 

As of May 2011, C. praegracilis seems to be lighter green and to grow taller than C. pansa. C. pansa may be spreading a bit more.

C. praegracilis (left), C. pansa (right), May 2011
C. praegracilis (left), C. pansa (right), May 2011

Slow and non-uniform spread of C. praegracilis
Slow and non-uniform spread of C. praegracilis

C. pansa plug on left spreading 2 directions, plug on right not at all yet
C. pansa plug on left spreading 2 directions, plug on right not at all yet
 

C. praegracilis and C. pansa, August 2011
C. praegracilis and C. pansa, August 2011
By mid-August, both of the Carex species have filled in.

In this photo all three split plots--each with C. praegracillis closest to the viewer. It grows taller than C. pansa.

 

 

 

 

 

 

 

 

 

For more information on Carex turf, see these web sites:

Carex pansa (Pacific dune sedge): The sedge with the other name, by David Amme.

Carex pansa photos, by David Amme 

Webmaster Email: caingels@ucanr.edu