Native Grasses and Sedges
Grasses are often an overlooked part of the ecosystem. Your first thought may be, "Lawns are grass, so why should I be adding some to the garden?" That's a great question! Mowed lawns don't allow space or a safe place for wildlife, insects, and pollinators to live. To add onto that, most lawns are made from non-native turf grasses that our native wildlife will not use as a preferred food source. Allowing native grasses to grow to their mature height as a part of the garden will allow the grass to feed and provide shelter for wildlife! It will also increase the chances of wild populations of native grasses establishing themselves in areas such as under power line right aways and other "unused" areas that our native insects and other wildlife may find themselves in. For more information on why native plants are so important for our ecology surrounding us, check out the article titled "Why Native Plants?" There are also articles, similar to this one, that suggest different native perennials, trees, and shrubs. Planting native is one of the easiest ways to help combat habitat loss.
Before we begin to dive into the specifics on each species on this list, there is something important to note. There is a difference between grasses and sedges, though they are often lumped together as one. Sedges are in the family Cyperaceae, while grasses are in the family Poaceae. The grass family is the fifth largest plant family, that includes familiar members such as bamboo or wheat. Cyperaceae is considerably smaller, yet still a large family. Sedges and grasses are easy to tell apart with the mneumonic "sedges have edges." Sedges have usually triangular cross sections, with their leaves forming whorls, while grasses have round cross sections with alternate leaves. Rushes are another grass-like plant that can often be grouped together or closely associated. Juncaceae, the rush family, is considerably smaller than the previous two. While none of these plant family members are closely related to those of the other two families, they are all similar to one another both in form and, occasionally, ecological function.
Always be sure to double check the native range of plants before you install them into your landscape, only to later find out that you are outside of their native range. This list will focus on the Pittsburgh area and the northeast, though many of these plants have an extensive range. If the specific species does not extend its range into your region, there is a high chance that there is a closely related species in the same genus that is! The following list is in no particular order and each species has its own pros and cons. Allow us to begin with one species many of us may already be familiar with.
1. Big Bluestem Andropogon gerardii
Zones: 4-9
Size: 3-6 feet tall, 1-3 feet wide
Sun: 6+ hours
Wildlife: butterflies and moths, insects, mammals, small birds
Big bluestem is one of the charismatic grasses, it is almost a celebrity when it comes to native grasses. As a warm season grass, it grows the most and the best during the warm summer months. This plant grows well in most circumstances and is easily grown in average to dry soils in full sun. Use this grass as an accent in the landscape, as you would other decorative grasses you may be more familiar with. The root system is extensive, more so than turf grasses. While it takes a while to establish, once it has the chance to get settled, it has wonderful drought tolerance. In fall, the foliage displays wonderful fall color ranging from golden to pink.
This plant is a larval host for a variety of butterflies, including the northern pearly eye, common wood nymph, and various skipper species. Many species of insects, including lightning bugs, will use the grasses as shelter. Small mammals and birds will also take shelter in the living plants. Some species of birds will use the foliage from past years' growth to build their nests.
2. Penn Sedge Carex pensylvanica
Zones: 3-8
Size: 6-12 inches tall and wide
Sun: 2-6+ hours, dappled shade
Wildlife: butterflies, moths, moths, small plants
Penn sedge also goes by wood sedge or oak sedge. Many species of grasses need to have full sun in order to thrive, but Pennsylvania sedge can tolerate full sun to deep shade and everything in between. While it does best in dry part to full shade, if grown in full sun conditions, it will benefit from a more moist environment. As a cool season sedge, this plant will grow best in spring and fall when temperatures are cooler. This is a wonderful lawn substitution, especially for the shady parts of the lawn, though it will not tolerate heavy food traffic. When allowed to grow, this sedge will create a wonderful, rolling-meadow appearance to your lawns. It will only need mowed once or twice per season, as this doesn't grow tall.
Various satyr butterfly larvae will use this plant as a larval host. Some birds will use the older foliage to make nests. Insects will use the foliage as shelter.
3. Little Bluestem Schizachyrium scoparium
Zones: 3-9
Size: 2-4 feet tall, 1-2 feet wide
Sun: 6+ hours
Wildlife: butterflies and moths, grasshoppers, leafhoppers, insects, birds, small mammals
While their common names may seem to indicate the contrary, big and little bluestem are botanical cousins, rather than siblings. They're both true grasses, but they are in different genera. Little bluestem's range runs nearly coast to coast, only a few states in the continental USA are excluded from its territory. While this grass is growing, it is valued for its wonderful blueish coloration, in fall the color transforms to a deep purple with a hint of brown. Some varieties have a brilliant red or chestnut color. In fall, the grass will sport white, airy seed heads. This species is tenacious, tolerating a wide range of soils, including clay, as well as superb drought tolerance, but also surviving well in areas with moist soils.
Little bluestem provides cover for birds, small mammals and insects year round. Winter is especially important for overwintering sites. Without shelter during the winter, insects and other animals may not survive the harsh season. Often, bumblebee queens will be seen nesting at the bases of grasses for the cold season until they emerge in spring. Little bluestem is one of the grasses they are often seen nesting in. Several species of skipper butterflies use them as larval host plants. Spittle bugs, grasshoppers, and a variety of other insects also feed on their stems. Songbirds will feed on their seeds.
4. Switchgrass Panicum virgatum
Zones: 5-9
Size: 3-6 feet tall, 2-3 feet wide
Sun: 4-6+ hours
Wildlife: birds, mammals, pollinators
Panicum virgatum is a warm season grass, growing the most in the hot summer months. It is a clump forming grass that spreads via rhizomes and readily self seeds, making it one of the last recommendations for smaller areas, lest it take over. The bunching habit is important. It allows for small animals and birds to run through the tall grasses while still being sheltered from above by the grass canopy. Allowing non native turf grasses to grow does not have the same effect as the bunch grasses and will be too dense for the animals who utilize the paths under the bunch grasses to travel. Swithgrass is a wonderfully versatile grass that can tolerate a wide range of soil and moisture conditions. While it grows best in moist sandy or clay soils, it can tolerate both dry soils and occasional flooding. Full sun is best for this species of grass, as part shade may cause the grass to grow with a more open habit and potentially fall over. In fall, this grass will turn a brilliant golden color. This species of grass is tall enough to use as a screen, an accent in the landscape, or as a back border planting.
This is another species of grass that will provide important cover for wildlife all year round. This is another host plant for several skipper butterflies, as well as the common wood nymph. The seeds provide an important food source for songbirds and mammals in winter.
5. River Oats Chasmanthium latifolium
Zones: 3-8
Size: 2-5 feet tall, 1-2 feet wide
Sun: 4-6+ hours
Wildlife: caterpillars, birds, mammals
River oats, Northern sea oats, wood oats, wild oats, and Chasmanthium latifolium are all names for the same plant. This grass is easily identified by its characteristic ornamental inflorescences and seed heads, which droop in an elegant, arching fashion. This is a wonderful grass for areas with lower lighting, as many of our native grasses require full sun to thrive. Tolerant of almost any soil conditions, river oats do the best when planted in an area with consistently moist soils. It is tolerant of mesic soils, as well, but thrives in rain gardens. You may recognize the seed heads from floral arrangements, where they are featured regularly. They turn a lovely golden, sometimes with shades of purple in the fall. The leaves will become a rich yellow in the fall, if given enough sunlight. This grass naturally occurs along the water's edge and in wetter areas. While it self seeds easily, if wild oats become too over crowded, they are easily divided and removed or replanted.
Several species of butterflies and moths will use this plant as a host plant for their caterpillars, such as skippers and northern pearly eyes. The seeds are an important food source for small mammals and birds. The grass provides cover needed for wildlife to hide from predators and the elements.
6. Common Wood Sedge Carex blanda
Zones: 3-9
Size: 12 inches tall, 24 inches wide
Sun: 2-6+ hours
Wildlife: pollinators, birds, small mammals
Possibly the most versatile plant on this list, this sedge can tolerate full sun to full shade, wet to dry soils, and a wide range of soil types. If planted in a dry location, be sure there is enough shade to allow this plant to thrive. This species of sedge makes a wonderful addition to landscapes with its short profile, perfect for bed borders. As an evergreen to semi-evergreen, wood sedge adds interest to the landscape year-round. This plant is deer and rabbit resistant and has potential to spread aggressively if there is a lot of bare soil or mulch in an area, though is also easy to contain with manual pulling and division. If planted in a cottage style garden, where the landscape beds are full to the brim with plants, it will not spread as aggressively as it does in disturbed or unoccupied areas.
Various species of insects will use wood sedge as shelter and protection from predators, as well as a food source. Some of these insects include lightning bugs, several butterfly larvae, and leaf hoppers. Many songbirds, game birds, and squirrels will feed on their seeds.
7. Indian Grass Sorghastrum nutans
Zones: 4-9
Size: 3-5 feet tall, 1-2 feet wide
Sun: 6+ hours
Wildlife: Songbirds, mammals, grasshoppers, pollinators
Indian grass is a tall, warm season bunch grass, making it wonderful for accents in the landscape around the home. This grass is a dominant species in tall grass prairies in certain parts of the country, tolerating both rocky and clay soils medium to dry soils. It has the potential to naturalize an area by self seeding in ideal conditions, though seedlings are easily maintained by manual pulling. If grown in areas with more moisture, the growth habit tends to be more open than in mesic or dry areas. It tolerates occasionally wet soils well. During active growth, the leaves are green with a tint of blue, which will turn a wonderful shade of yellow-orange in fall. Sorghastrum nutans is deer resistant.
Indian grass is a larval host plant for a variety of skipper butterflies and is a preferred food choice for some species of grasshoppers. It provides excellent cover for small mammals, insects, and birds year-round. The seeds are eaten by songbirds and small mammals.
8. Prairie Dropseed Sporobolus heterolepis
Zones: 3-9
Size: 2-3 feet tall and wide
Sun: 4-6+ hours
Wildlife: songbirds, insects
Prairie dropseed is a grass that is highly recommended for use in home landscaping. It has a soft, feathery visual texture and stays a small size with little to no maintenance. Another clumping, warm season grass, this plant does best with average to dry, well drained soils in full sun though is tolerant of a wide variety of soils, including heavy clay. Though it is a slow grower and slow to establish, it has wonderful drought tolerance when it becomes settled into the landscape. The USDA has prairie dropseed listed as endangered in several states of its native range including Ohio and North Carolina. In many more states and provinces within its range, its populations are in decline. You can find this species of grass growing naturally in prairies and glades nearly across the continent. During active growth, the leaves are a bright green which then turn coppery brown in fall.
Like many other grasses on this list, Sporobolus heterolepis is the host plant of choice for some species of skipper butterflies. Grasshoppers and leafhoppers use this plant as a food source, as well as various songbirds that snack on the seeds. Insects such as lightning and ladybugs will use the grass as a hiding space during their sleeping hours.
9. Purple Love Grass Eragrostis spectabilis
Zones: 5-9
Size: 1-2 feet tall and wide
Sun: 6+ hours
Wildlife: birds, small mammals
This is possibly the most unique grass on this list. It earns the "purple" portion of its name with the airy, almost cloud or mist like purple seeds this grass produces. It is easily used as a small accent plant or a border plant in the landscape. Purple love grass is one that tolerates dry conditions and will naturalize well in a rock garden or other areas with sandy soils. This grass is tolerant of road salts and black walnut, though struggles in heavy clay or wet soils.
Small insects will use this plant as cover during their sleeping hours, such as lightning bugs. Eragrostis spectabilis is a larval host plant for several species of moths and butterflies. It is also a frequent buffet location for a large variety of herbivorous insects. Birds will use the dried seed heads and leaf blades from last season to create their nests. Birds and small mammals eat the seeds.
10. Cord Grass Spartina pectinata
Zones: 4-9
Size: 4-7 feet tall and wide
Sun: 4-6+ hours
Wildlife: birds, pollinators, small mammals
Cord grass is an incredibly important wetland species. This plant does best in average to wet loamy soils, and can be found growing along the water's edge, wet prairies, swamps, and other similar habitats. While it performs best in loam, it can adapt well to a wide variety of soil types if adequate moisture is provided. Spartina pectinata is a warm season grass that typically grows about as wide as it is tall, meaning it may not be suitable for small landscaping projects. The leaves of this species have sharp edges, so be mindful and wear gloves when working with it. The leaves are a deep green when in the growing season and turn to a warm yellow in fall.
The seed heads of this grass provide an important food source to a variety of insects, ducks, geese, muskrats, and other wetland wildlife. The rootstock is often eaten by some of the same animals. Cord grass is a host plant for a variety of moth species in their larval stage. This grass also provides important nesting sites for wetland wildlife.
Grasses and sedges are incredibly important to our ecology. They provide food for a large swath of animals, provide hiding places and habitats to even more, help to prevent erosion, and so much more. Adding native grasses and sedges to the landscaping around your home can add a excellent accent or border, as well as a place to house some caterpillars or lightning bugs. They give building material for birds to create their nests with, and beauty for us to enjoy. While it may seem as though just replacing a few non native plants with native ones in your landscape doesn't make much of an impact, little bits add up! If everyone in the neighborhood did the same, transform as much of their landscaping into native plants as they can, amazing changes would begin to take place. More butterflies and birds would come to town for us to enjoy! Changes like this don't have to happen all at once. Replacing a few plants at a time is a great way to dip your toes into native gardening. If we all work together, we can make big change!
Works Cited
Carex blanda (common woodland sedge). Minnesota Wildflowers a Field Guide. (n.d.). https://www.minnesotawildflowers.info/grass-sedge-rush/common-woodland-sedge
Carex pensylvanica. Carex pensylvanica (Oak Sedge, Pennsylvania Sedge, Plantainleaf Sedge, Rush, Sedge, Sedges, Seersucker Sedge) | North Carolina Extension Gardener Plant Toolbox. (n.d.). https://plants.ces.ncsu.edu/plants/carex-pensylvanica/
Chasmanthium latifolium. Missouri Botanical Garden. (n.d.). https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=a240
Common Woodland Sedge (Carex blanda). Illinois Wildflowers. (n.d.). https://illinoiswildflowers.info/grasses/plants/cm_wdsedge.htm
New England Wild Flower Society (http://plantfinder.nativeplanttrust.org). (n.d.). Eragrostis spectabilis. New England Wild Flower Society. https://plantfinder.nativeplanttrust.org/plant/Eragrostis-spectabilis
Schizachyrium scoparium - little bluestem. Prairie Moon Nursery. (n.d.). https://www.prairiemoon.com/schizachyrium-scoparium-little-bluestem-prairie-moon-nursery.html
Sporobolus heterolepis. USDA Fire Effects Information System (FEIS). (n.d.). https://www.fs.usda.gov/database/feis/plants/graminoid/spohet/all.html