Diggin' In: Ornamental fall grasses and their skipper friends 

October 13, 2014

Fall puts on its finery when the ornamental grasses appear ó their plumes shimmering and shining in the autumn sun.

Ornamental grasses are also practical in the home garden because birds and small mammals like their small seeds while deer dislike anything about them, according to Helen Hamilton, author of "Wildflowers and Grasses of Virginiaís Coastal Plain."

"Mixed with perennial flowers and shrubs, their erect stems and leaves provide a nice contrast to the garden landscape," she says. 

"Most have wide and deep roots that discourage weed seeds. Research has shown better growth of wildflowers in meadows where native grasses flourish."

As larval hosts for many species of skipper butterflies, the plants should remain uncut over the winter, until new growth appears in early spring. Many other beneficial insects lay their eggs and develop as larvae over the winter in the hollow stems of grasses and other late season vegetation."

Here are some native ornamental grasses to consider for the home garden, courtesy Hamilton:

Little bluestem (Schizachyrium scoparium ). An excellent forage grass, little bluestem was once the most abundant species in the American prairie. Blue-green only when the shoots first come up in the early summer, the leaves and flowering stalks become a rich mixture of tan, brown, and wine-red through the fall and winter. The grass grows five feet tall, with wiry flowering branches intermingled with leaves. A distinguishing feature is the bent awns on the mature seed heads in clusters lining the branches. The grass is larval host for four skipper butterflies, including the local swarthy and crossline skipper. Itís native to almost every U.S. state.

Purpletop (Tridens flavus). Purpletop is noticeable late summer for its loose, open, purple flower clusters in a weeping form. The slender perennial grows 4 feet tall. The large purple seeds are widely spaced on thin panicle-branches. Birds eat the plants nutritious, fatty seeds, and this robust grass provides significant cover for wildlife. Purpletop is the larval host for two species of grass skippers, crossline and little glassywing, and also for the broad-winged skipper and large wood nymph. Itís native to 37 states, including California, according to the National Resources Conservation Serviceís plant database at .

Switchgrass (Panicum virgatum). Once one of the dominant species of the tall-grass prairie, switchgrass now grows on dunes, shores, along the edges of ponds and marshes. As larval host for the tawny-edged skipper, Delaware skipper, northern broken-dash and little glassywing, it has leaves and stems that should remain uncut over the winter. In March when new growth appears, the tan stems and leaves can be cut off in long segments, and left as mulch around the plant. Switchgrass is good for erosion control and furnishes food for small birds. Itís native to all 48 lower U.S. states, except California, Washington and Oregon.

Rice cutgrass (Leersia oryzoides), giant cutgrass (Zizaniopsis miliacea).These two grasses are hosts for the caterpillars of skippers that live in coastal counties. The native cool-season grass grows and flowers late in the summer, producing seeds that are important food for waterfowl, small mammals and shorebirds. Growing two to three feet tall, the grass spreads by underground rhizomes and often forms dense colonies. Rice cutgrass is appropriately named because the sharp, abrasive leaves can cut skin and cling to clothing. Giant cutgrass is taller, growing to 12 feet tall with stout stems in shallow marshes, swamps and ditches. The flowering stems produce roots and new plants at the nodes when they touch the water. Rice cutgrass is native to all 48 lower U.S. states; giant cutgrass grows in more than a dozen southeastern U.S. states.

Now letís meet some skippers. Gardeners and their cameras are drawn to butterflies, especially eye-catching swallowtails, pearl crescents, buckeyes and monarchs

"These Ďflowers of the airí usually have large wings, colorful scales and feed on nectar for long periods, allowing easy photographing," she says.

"But there are other members of the Lepidoptera in our gardens, less conspicuous and flying faster. Moths have feathery antennae and hold their wings flat at rest; stout, fat-bodied skipper butterflies have clubbed antennae, often with hooks and enormous eyes.

"Within the last group, grass skippers lay their eggs on grasses and sedges, and the caterpillars roll the edges of the leaves to make a shelter, sealing the edges with silk. At rest their hind wings are flat on the surface and the front wings are held at a 45 degree angle. No other lepidopteran shows this combination of very stout body, clubbed antennae and hind and front wings in different positions. While easily identified by the appearance of the wings at rest, they do not rest long, and move very quickly, making identification and photography difficult.

"These insects are just one group of many that fill niches in our gardens, in ecosystems. As they feed on leaves and process sunís energy, their fat bodies as larvae and adults provide food to birds and their young."

Here are some skippers you may see in your yard, says Hamilton:

Fiery skipper (Hylephila phyleus). With bright orange and black markings, fiery skippers are more easily recognizable than other grass skippers. While they feed on the nectar from the flowers of the native swamp milkweed, asters, sneezeweed and ironweed, the males wait for receptive females in short grasses such as Bermuda grass and crabgrass. Females lay their eggs under leaves of these grasses which furnish food for the caterpillars. While feeding, they roll the leaves and tie them with silk to make shelters lying horizontally in the sod.

Least skipper (Ancyloxypha numitor). Also with orange and black markings, the females favor native marsh grasses such as marsh millet and rice cutgrass as food for their caterpillars. The adults feed on plants such as pickerelweed, chicory and white clover, growing in ditches, slow streams, and marshes. Three broods hatch May-October.

Northern broken-dash (Wallengrenia egeremet). These skippers fly slowly and are mostly dark brown in color. There is only one brood June-August; caterpillars develop in the leaves of the panic grasses and deer tongue grasses. The adults feed on nectar from flowers that are white, pink or purple such as native dogbane, New Jersey tea and sweet pepperbush.

Zabulon skipper. Brown-purple butterflies with yellow markings, zabulons make two broods May-September. After caterpillars emerge from their shelters of silk-tied leaves, they feed on lovegrass, wildrye, purpletop, bentgrass, orchardgrass, bluegrass and wheatgrass.

Little glassywing (Pompeius verna). Brown skippers have a transparent white spot on the fore wing. Only one brood is produced, in June-August. Caterpillars feed exclusively on purpletop where they develop in their shelters of rolled or tied leaves. Adults seek nectar from white, pink and purple flowers such as dogbane, Joe-pye-weed, common milkweed and swamp milkweed.

Broad-winged skipper (Poanes viator). Another yellow, black-brown grass skipper with one or two broods yearly June-August. Caterpillars feed on sedges, tall cordgrass, giant cutgrass, wild rice and marsh millet. Inland adults like nectar on swamp milkweed and blue vervain while coastal populations feed on dogbane, pickerelweed and sweetscent.



Associated Press