Deergrass (Rigens)

The Deergrass (Rigens) is generally described as a perennial graminoid. This is native to the U.S. (United States) has its most active growth period in the spring and summer . The greatest bloom is usually observed in the late spring, with fruit and seed production starting in the summer and continuing until summer. Leaves are not retained year to year. The Deergrass (Rigens) has a long life span relative to most other plant species and a moderate growth rate. At maturity, the typical Deergrass (Rigens) will reach up to 4.5 feet high, with a maximum height at 20 years of 0 inches.

The Deergrass (Rigens) is easily found in nurseries, garden stores and other plant dealers and distributors. It can be propagated by seed. It has a slow ability to spread through seed production and the seedlings have medium vigor. Note that cold stratification is not required for seed germination and the plant cannot survive exposure to temperatures below 23°F. has high tolerance to drought and restricted water conditions.

Uses of : Landscaping, Medicinal, Culinary, etc.

In California, dense patches of deergrass provide cover during the fawning period of mule deer (Odocoileus hemionus) in mountain meadows and grassland openings. The younger palatable tufts are grazed by deer, horses, and cattle and can remain palatable if continually grazed. It is particularly sought for forage by animals when first resprouting after a burn. Older tufts are poor feed for livestock. The seeds provide food for songbirds and probably other birds as well. In sunny openings where deergrass occurs, it forms a larval food plant for one of the Satyrid butterflies, the California ringlet (Coenonympha california) and for the umber skipper (Poanes melane). Massive numbers of ladybugs overwinter in deergrass clumps. Deergrass is a valuable streambank stabilizer, as it has an extensive root system, and if grown in dense enough colonies, it can be an effective weed suppresser. In California, Pacific Gas and Electric is experimenting with growing it in dense colonies under powerline corridors. Its long, slender culms (stems) and tall tufts make it an attractive plant for the garden.

Deergrass is a significant species to central and southern California Native Americans who utilize the flower stalks in the foundations of coiled baskets. Frequently, thousands of flower stalks are needed for completion of each basket. Culms are gathered in late spring while still green, or summer or early fall when golden brown depending upon the tribe, individual family preference, and elevation of the deergrass site.

General Characteristics

Muhlenbergia rigens (Benth.) A.S. Hitchc., deergrass, is a perennial bunchgrass reaching heights of 5 feet when in bloom. It is part of the largest genus of warm season grasses in North America. The bunchgrass is found in dense, large clumps, but can occur as a continuous cover in areas that are subjected to light or frequent ground fires. The culms are slender, narrow, and spike-like, 3 to 4 feet in length and less than 1/2 inch wide. The numerous, small spikelets each have one flower. The ligule (where the leaf blade meets the stem) is firm and blunt, 1/8 inch long. The leaves are 1/16 to 5/16 inch wide. The seeds are small, requiring about 2.5 million to make one pound. The dense, basal foliage is tufted and these large tufts, up to 6 feet across, are a distinguishing feature of the grass, along with the whip-like flower stalks.

Required Growing Conditions

It is found on sandy or gravely well-drained soils in scattered colonies in dry or damp places below 7,000 feet elevation from Shasta County in northern California south, extending into New Mexico, Texas, and Mexico. Deergrass can withstand periodic flooding, but it cannot tolerate poorly-drained soils.

The major plant communities it inhabits include valley grasslands, streamsides, and meadows. Additionally, deergrass is shade-intolerant and occurs in grassland openings within chaparral, mixed conifer forests, and oak woodland plant communities, maintained with human-set or lightning fires. On most soil types, these grassland areas quickly revert to the surrounding dominant vegetation type without human or natural disturbance.

Cultivation and Care

Broadcast seeding: In California and the Southwest, deergrass can be broadcast seeded in the late spring or summer during the months of May, June, July, and August, with irrigation. The seeds are tiny and should be broadcast on top of the ground, and then run over with a ring roller or a culti-packer to compress the seeds slightly below the soil surface. For best results, sow at least 4 pounds of PLS (pure live seed) per acre, which amounts to 50 seeds per square foot. Deergrass is slow-growing and germination rates can vary from 2 weeks up to 2 months. Fertilization of deergrass is not recommended, as it usually gives weeds a competitive edge. Site preparation is extremely important for good establishment of deergrass. Both repetitive tillage and burning are recommended to drastically curtail weed competition. Repetitive tillage involves loosening the soil, irrigating, and cultivating the area with a disc harrow, following with a ring roller to kill the flush of annual weeds. This is done several times prior to seeding to reduce the weed seedbank. Burning involves setting fire to all residual dry matter prior to seeding. Container planting: Container planting is a more effective and less time consuming way of establishing deergrass, but it is more costly than seeding on a large scale. Deergrass seed can be sown into flats, seedling plug trays, or reforestation tubes in May. Plants can be planted out from containers in the fall of the same year in soil that has been moistened with the first rains, using standard planting procedures. Plants can also be sown in the fall in flats or containers and planted out the next summer or fall in the designated area. Plants should be spaced at a minimum width of 24 inches. Irrigating is not necessary if it is a normal rainfall year. Site preparation is the same as for the section under broadcasting seed. Larger bunchgrasses can also be divided in winter or early spring and transplanted. A good stand of deergrass can be established in 1½ years by container planting. It is thought that container planting with grown plugs is more effective in establishing deergrass than by seed.

General Upkeep and Control

Once established, deergrass is quite drought-tolerant. To maintain its vigor and reduce accumulated dead material, deergrass can be mowed or burned every several years. Burning or mowing should be in the fall, after it has gone to seed. Many tribes historically and probably prehistorically enhanced deergrass populations through firing deergrass stands in the fall in California every 2 to 5 years. Fires set by Native Americans increased flower stalk yields, recycled nutrients, cleared away detritus, and promoted seedling production in the midst of reduced competition from other plants. According to Native American elders, these fires maintained the bunchgrass in greater numbers than would have occurred under natural conditions. Knowledge of past indigenous fire management of deergrass has important implications for mountain meadow habitat management for wildlife and maintenance of grassland openings within shrublands, woodlands, and forests for preservation of indigenous cultural traditions. Some areas could be managed with the dual objectives of indigenous harvesting of flower stalks and grazing after culm harvest.

Pests and Potential Problems There are several fungi that infect the leaves of deergrass, causing debilitation, but usually not death. These include tar spot (Phyllachora epicampis), two rusts (Puccinia schedonnardi and Uromyces epicampis), and stripe smut (Ustilago striiformis). Fire eliminates these pathogens.

Cultivars, Improved, and Selected Materials (and area of origin) Deergrass plant materials are available from commercial sources.

Plant Basics
Category
Growth Rate Moderate
General Type Graminoid
Growth Period Spring, Summer
Growth Duration Perennial
Lifespan Long
Plant Nativity Native to U.S.
Commercial Availability Routinely Available
Physical Characteristics
Bloom Period Late Spring
Displays Fall Colors No
Shape/Growth Form Bunch
Drought Tolerance High
Shade Tolerance Intermediate
Height When Mature 4.5
Vegetative Spread None
Flower Color Yellow
Flower Conspicuousness No
Fruit/Seed Abundance Medium
Fruit/Seed Seasonality Summer Summer
Seed Spread Rate Slow
Gardening Characteristics
Propagations (Ways to Grow) Seed
Moisture Requirements Low
Cold Stratification Required No
Minimum Temperature 23
Soil Depth for Roots 14
Toxic to Nearby Plants No
Toxic to Livestock No
After-Harvest Regrowth Rate Slow
After-Harvest Resprout Ability No
Responds to Coppicing No
Growth Requirements
pH Range 5.5–7.5 pH
Precipitation Range 10–10 inches/yr
Planting Density 0–0 indiv./acre
Soil Textures Coarse, Medium
Soil Depth for Roots 14
Minimum Frost-Free Days 334 day(s)
Salinity Tolerance Low
CaCO3 Tolerance None
Sustainability & Use
Leaf Retention No
Palatability Low
Fire Resistant No
Causes Livestock Bloating None

Source: USDA, NRCS, PLANTS Database, plants.usda.gov.
National Plant Data Center, Baton Rouge, LA 70874-4490 USA