Sedges and Native Grasses for the Shade
by Kevin Tungesvick

ARTICLE FIRST APPEARED: 2000 Summer

Often, as spring wanes, our woodland wildflower gardens quickly fade into a nondescript mixture of bare ground, yellowing ephemerals, and miscellaneous greenery. Unfortunately the vast majority of wildflower gardeners have neglected to include some of the numerous graminoid or grassy species native to our woodlands. Grasses and sedges provide soil stabilization, wildlife habitat, and attractive forms and textures throughout the seasons. Many species have ornamental value, but have remained obscure due to a difficult taxonomy and people's lack of interest in woodland habitats after the spring ephemerals have faded.

Sedges are often particularly abundant in forested habitats. Dozens of woodland species occur in every state in the East and Midwest. The most attractive ones for ornamental use can roughly be divided into two groups: species with broad, strap-like foliage and species with fine grassy foliage.

SEDGES WITH BROAD, STRAP-LIKE FOLIAGE:
Great for Specimens in the Shady Garden

Plantain-Leaved Wood or Seersucker Sedge [Carex plantaginea] is perhaps the best known and most available of the broad-leaf species. It features evergreen leaves around an inch wide and up to 1 foot long that are abundantly pleated. Native to rich wooded slopes and ravines in the northeast and Appalachian Mountains as well as the beech/maple forests of southwestern Michigan, it has purplish tints in the new growth. Its inflorescence appears in early spring, featuring showy yellow stamens. It is particularly attractive when planted on slopes where its lush foliage drapes gracefully downward.

The similar broad-leaved wood sedge [Carex platyphylla] differs by having glaucous blue-green leaves without purplish tints. Also native to northeastern beech/maple woodlands, it prefers moist humus-rich soil and filtered shade.

A very common broadleaf sedge of calcareous Midwestern woodlands is the blunt-scaled wood sedge [Carex albursina]. Its foliage is 6 to 8 inches long and up to 2 inches wide, resembling the ramp, Allium trioccum, in size and shape. Finally, beech wood sedge [Carex laxiflora] is another species native to Midwestern woodlands with long draping strap-like foliage.

SEDGES WITH FINE, GRASSY FOLIAGE:
Useful for Groundcovers in Woodlands

While broadleaf sedges are useful as specimens in the shaded garden, fine-textured species may form an attractive groundcover in woodland areas.

Penn or common oak sedge [Carex pensylvanica] has very fine foliage, forming a lush carpet in its favored habitat of well drained oak-hickory woodlands. Spreading by rhizomes, it grows around six inches tall. Unlike clumping species, it can form large monotypic stands that may dominate large areas of favorable habitat.

Wood's stiff sedge [Carex woodii] is an elegant deep green rhizomatous species that holds promise as a similar groundcover in mesic woods.

Straight-styled wood sedge [Carex radiata], a sedge of moist woodlands, is a beautiful species that makes a graceful fountain of bright green, extremely fine foliage. These attractive clumps reach 10 inches high and wide. They provide an outstanding texture contrast when planted with broadleaf wildflowers such as celandine poppy [Stylophorum diphyllum], Virginia bluebells [Mertensia virginica], and zig-zag goldenrod [Solidago flexicaulis]. For drier sites, a sister species, curly-styled wood sedge [Carex rosea] provides the same effect. These species also make outstanding mass plantings for shade when placed on ten-inch centers. Grass sedge [Carex jamesii], a versatile species found in many different types of woodlands, has a unique "liriope-like" appearance throughout the year. It seems to tolerate dense shade under sugar maples as long as the sapling layer is not too thick. Growing 6 inches tall, it forms a hummocky cover when planted on one foot centers, adding texture and interest to flat sites.

Sedges for Damp or Wet Shade
Brome hummock sedge [Carex bromoides] is an attractive species of wet woodlands, ideal for damp shady settings or shaded water gardens. It consists of a dense clump of fine graceful foliage, resembling prairie dropseed [Sporobolus heterolepis] in size and form.

Long-beaked sedge [Carex sprengelii] is a bold woodland sedge that occurs in a variety of moist woodland situations. It features a large clump of graceful medium-textured foliage up to 2 feet in height. Attractive pendulous spikelets [seedheads] add to its appearance in spring and early summer.

While the above species are primarily grown for their foliage, several species native to moist woods also have interesting and attractive seedheads. Palm or swamp oval sedge [Carex muskingumensis] has clusters of long pointed seedheads on 18 to 24 inch stalks above lush, shiny, dark green foliage that forms a bushy clump. It is outstanding in formal mass plantings or as an addition to woodland gardens.

While all sedge seeds are enclosed in a husk-like structure known as a perigynia, certain species have a great inflated perigynia that exaggerates the size of the seedhead. Best known in this group of sedges is common bur sedge [Carex grayi]. The round 1-inch seedheads resemble the spiny appearance of a mace carried by medieval knights. It grows 18 inches tall, tolerating sun or shade in moist soil. Common hop sedge [Carex lupulina] differs by having an elongated seedhead that often droops gracefully. Both of these species occur in wet woods, but adapt to moist upland sites.

Midwestern Native Grasses for Shade
A variety of native woodland grasses also holds much promise as ornamental shade plants. While a few species such as Northern sea oats [Chasmanthium latifolium] and bottlebrush grass [Hystrix patula] are relatively widespread in the nursery trade, many species remain relatively unknown.

Common wood reed [Cinna arundinacea] is one of the most dramatic woodland grasses. The bright green foliage is attractive throughout the growing season. Growing 3-5 feet, erect seed heads similar to Indian grass [Sorghastrum nutans] appear in mid- summer. The inflorescence emerges green, maturing to a rich brown and remaining attractive through the fall months. Native to floodplains and damp woods, it performs best in moist soil and filtered shade where it will form a showy clump. The seedheads are outstanding in dried arrangements.

Ear-leaved brome [Bromus latiglumis] is another attractive grass of floodplain woods, growing 3-4 feet. The robust leafy culms produce abundantly branched seedheads in early- to mid- summer. The seeds mature to golden brown, persisting through fall. Like wood reed, it performs best in moist soil and filtered shade. Woodland brome [Bromus pubescens] is a smaller species of drier woods that grows 2 to 3 feet. While not as showy as tall brome, it is more tolerant of dry shade. Unlike the non-native smooth brome [Bromus inermis], these species do not spread by rhizomes, making them a well-behaved addition to the woodland garden.

Bottlebrush grass [Hystrix patula] is a 3 to 4 foot grass with airy bottlebrush-like seedheads appearing in June. The seedheads often last until early fall. It is particularly attractive when massed in filtered shade of tall trees. Bottlebrush grass is very easy to grow, thriving in moist or dry soil.

Silky wild rye [Elymus villosus] is a small, pleasant bunch grass of woodlands. Growing only about eighteen inches in height, it is very adaptable to various soil and moisture conditions. The seedheads are smaller and denser than bottlebrush grass, nodding gracefully in summer and fall. While not showy enough to make a dramatic specimen, it is an attractive part of a naturalized woodland community. Both silky wild rye and bottlebrush grass will readily naturalize in the woodland garden, a desirable trait since they are relatively short-lived perennials.

Beak grass [Diarrhena americana] is a beautiful but little known grass of wooded slopes and banks. It has shiny, dark green, arching foliage about 1/4" inch wide and up to 18 inches long. Graceful drooping seedheads appear in late summer, producing large hard seeds which remain through autumn. The foliage turns rich golden brown in autumn and fades to an attractive tan color throughout the winter. This species makes an attractive groundcover when placed on one foot centers. Beak grass is tolerant of drought and deep shade, making it useful for soil stabilization on shaded slopes.

Perhaps the best known and most ornamental of our native woodland grasses is Northern sea oats [Chasmanthium latifolium]. The highly ornamental flattened seedheads emerge green in mid summer, turning brown at maturity and persisting well into winter. The broad, attractive foliage remains lush throughout the growing season. Northern sea oats is equally attractive as a mass planting or a specimen in the woodland garden.

Whether they are used as part of a woodland restoration, a shaded mass planting, or as a unique groundcover, native woodland grasses and sedges deserve a place in our gardens and landscapes. The beautiful textures and forms of these species add season long interest to entice visitors to our shaded gardens long after spring has passed.

Kevin Tungesvick is manager of Spence Restoration Nursery in Muncie, IN, a wholesale producer of native wetland, woodland, and prairie perennials. Specialties include wetland and woodland sedges, prairie and woodland grasses, sedge meadow wildflowers, and emergent plants. You can reach Kevin or order a catalog by calling (765) 286-7154 or kevin@spencenursery.com.

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