What is a Sedge? How is it Different From a Grass?

by cazort

A sedge is a member of a family of plants that are related to grasses and are grass-like in many respects, but are not true grasses.

Nearly everyone has seen sedges growing wild, but most people probably think of them as grasses. Sedges are close relatives of grasses, but are not grasses, and there are certain differences in the structure and form between grasses and sedges that make them easy to tell apart.

This page will first explain what a sedge is, how to distinguish sedges from grasses and other close relatives (like rushes), and then give specific examples of sedges, including common ones that you have likely seen if you live in Eastern North America, the area covered by this article.

What is a Sedge? The Sedge Family

The sedge family, Cyperaceae, is a large plant family that is related to, but distinct from grasses (Poaceae).

Sedges are defined as plants belonging to the sedge family, Cyperaceae. This family is a large and diverse group of plants that superficially resemble grasses and rushes, but share certain distinctive characteristics.

The easiest way to tell sedges apart from grasses is to examine the stems.  Most grasses have hollow stems.  Sedge stems have a distinctive triangular shape, with three sides.  Although a few grasses have solid stems, no grasses have triangular stems.  Rushes (another closely related group) have round, but not hollow stems.

The flowers and fruit (seeds) of sedges are also distinct from grasses, and although these differences are very easy to see, it is hard to concisely describe the differences between flowers and fruits between grasses and sedges without going into a lot of botanical terminology.

The largest genus of sedges belong to the genus Carex, and these species are often called the "true sedges".  But there are many other plants, such as Cyperus, the "nutsedges", or Scirpus, bulrushes.

Examples of Sedge Stem Cross-sections
Cyperus rotundus stem, cross-section
Cyperus rotundus stem, cross-section
Carex appressa, stem cross-section
Carex appressa, stem cross-section

The Ecology of Sedges

Although sedges are diverse and have a wide range of habitat preferences, there is a fairly strong tendency among plants of this family to prefer growing in wet conditions, including wetlands and also moist woodlands.

Native sedges are of key importance to wildlife; their leaves and other plant parts are eaten by a wide variety of insects, including the caterpillars of a variety of moths and butterflies.  The seeds are eaten by numerous birds.  Birds and other animals also indirectly depend on sedges as a food source when they eat the numerous insects supported by these plants.

Sedges also provide cover and key structural elements of habitat for various animals, including cover and providing breeding habitat for birds.  One such bird, the Sedge wren, is named after this plant family, and is dependent on a wetland habitat which includes both sedges and short grasses.

This bird species depends on wetland habitats in which sedges are a key component.
Sedge wren
Sedge wren

Yellow nutsedge, Cyperus esculentus

Yellow nutsedge, Cyperus esculentus, is a common and abundant sedge that has an extremely broad distribution.  In the U.S., it is found in all lower 48 states as well as Hawaii, Puerto Rico, and the Virgin Islands, and its global range extends throughout most of the Western Hemisphere, southern Europe, Africa, the Middle East, and the Indian subcontinent.

The tubers of yellow nutsedge are edible, and are an important food source in Spain, where they are called "chufa".

You can find yellow nutsedge growing in lawns, where it often looks yellower in color than the surrounding grass, and has blades that frequently stretch taller and feel firmer to the touch than typical lawn grass.  It is easiest to identify when it blooms and forms seeds; the structure of the flowers and seed quickly identify it as a sedge and not a grass.

Although some people view yellow nutsedge as a weed, there is no need to remove this plant from your yard or garden, and it can actually be beneficial to leave it, by contributing to biodiversity, if you live in an area where it is native.

Yellow nutsedge growing in a lawn
Yellow nutsedge growing in a lawn

Pennsylvania Sedge, Carex pensylvanica

Pennsylvania Sedge, Carex pensylvanica, is a sedge native to Eastern North America and into the upper Midwest.  It has a grasslike appearance, with thin leaves.  Its preferred habit is shady habitats with dry, well-drained soils with at least a bit of organic material.  It naturally occurs in forested uplands and oak woodlands.

As a garden plant, it makes an excellent plant for a lawn-like groundcover that does not require mowing, in the dry shade conditions it prefers.  It will often look more attractive than grasses do under these conditions.  It does not, however, tolerate heavy foot traffic the way most lawn grasses do.

Fox Sedge or Brown Fox Sedge, Carex vulpinoidea

This sedge is adapted to wet to moist conditions in full sun to part shade.

Fox sedge, Carex vulpinoidea, is one of the most abundant species of sedge in North America, with a wide distribution across the continent.  This sedge prefers moist to wet conditions and full sun to partial shade.

It is often classified as a "cool season grass", even though it is not a grass, because it thrives in cold climates where it is hard to grow lawn grasses, and does most of its growing during the cooler seasons in spring and fall.

Learn More About Plants

Gardening with plants native to your local region has many advantages, including minimizing care, and helping to preserve and protect biodiversity in surrounding ecosystems.
Nitrogen fixing plants are a natural and sustainable way to add nitrogen to gardens, landscapes, and ecosystems, excellent for organic gardening.
Four common mistakes people make when trying to remove or control invasive or weedy plant species.
Updated: 08/28/2015, cazort
Thank you! Would you like to post a comment now?

Questions? Comments? Feedback?

Only logged-in users are allowed to comment. Login
blackspanielgallery on 08/12/2015

I would have just called all of these grass. Informative piece.

frankbeswick on 08/12/2015

A very useful article that concentrated my mind on an area of botany that I did not know as well as I might have done.

You might also like

Nitrogen Fixing Plants and Trees

Nitrogen fixing plants are a natural and sustainable way to add nitrogen to g...

4 Common Mistakes When Removing Invasive Plants

Four common mistakes people make when trying to remove or control invasive or...

Disclosure: This page generates income for authors based on affiliate relationships with our partners, including Amazon, Google and others.
Loading ...