Grasses in the Deciduous Forest

Forest Landscapes

• Grasses are generally associated with open, sunny fields, rather than forests. Yet in some types of forest, grasses dominate the ground cover. These forests are generally characterized by a high canopy and the light, dappled shade of widely-spaced deciduous trees. They are also likely to be found on south-facing slopes, where the hours of sun exposure are significantly higher over the course of a year. In home landscapes with similar conditions, grasses make a pleasant park-like atmosphere around large, deciduous trees -- the key is choosing the right type of grass.

Forest Grasses

• A couple common lawn grasses have enough shade tolerance to grow well in the filtered sunlight of large deciduous trees. Zoysia (Zoysia spp.) and fescue grasses (Festuca spp.) are the best choices and thrive in U.S. Department of Agriculture plant hardiness zones 5 to 10 and 3 through 7, respectively. Native "bunch" grasses are another option and are often better suited to the intense root competition of large trees than lawn grasses are. These grow in neat, tidy clumps, and their seed stalks give a light, airy feel as they wave in the breeze under a big tree. Not all bunch grasses are shade tolerant, but a local nursery can provide information on the best species for your region.

Grass-Like Plants

• Many plants seen in natural deciduous forests look like grasses, but are botanically unrelated. But for the purposes of landscape design, they provide the same look and feel of true grasses and should be considered for planting in woodland gardens. Many native sedges, reeds, and rushes grow in deciduous forests -- especially in wet soils -- and are useful as large-scale ground covers in the landscape. These are often available locally from native plant nurseries. Monkey grass (Liriope spp.), hardy in USDA zones 6 through 10, and mondo grass (Ophiobogon japonicus), hardy in USDA zones 6 through 9, are among the most commonly available shade-tolerant ground covers. These can be grown in mass plantings for a grass-like effect under deciduous trees.

Woodland Garden Management

• Lawn grasses under large deciduous trees usually become sparse over time because of the combination of shade and competition for water and nutrients. Plus, the woody roots of large trees often extend just above the soil surface, making the lawn there impossible to maintain with a mower. Bunch grasses are not suitable for maintaining with lawn mowers but can be allowed to grow in a naturalized fashion. Or, they can be kept tidy by cutting them back with garden shears each year after the seed stalks fade. To give grasses the most possible sunlight, trees should have all the limbs removed from the lower third of their total height.