Green Needlegrass (Viridula)

The Green Needlegrass (Viridula) 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 Green Needlegrass (Viridula) has a moderate life span relative to most other plant species and a rapid growth rate. At maturity, the typical Green Needlegrass (Viridula) will reach up to 2 feet high, with a maximum height at 20 years of 0 inches.

The Green Needlegrass (Viridula) 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 high vigor. Note that cold stratification is not required for seed germination and the plant cannot survive exposure to temperatures below -38°F. has high tolerance to drought and restricted water conditions.

Uses of : Landscaping, Medicinal, Culinary, etc.

Rangeland/hayland: Green needlegrass is well suited for use in mixtures for range seeding, critical area establishment, mineland revegetation, wildlife habitat, and other plantings where the establishment of native vegetation is the objective. This species is nutritious, palatable, but decreases under grazing use. The awns are not as troublesome to livestock as with other needlegrasses. Green needlegrass is frequently included in seedings of mixed midgrasses, but due partly to its hard seed coat, it may be slow to germinate and become established.

General Characteristics

General: Green needlegrass is a cool-season (C3) native perennial bunchgrass. It grows to a height of 18 to 36 inches. The seed head is a compacted panicle, varying from 4 to 10 inches in length. Flowering occurs in early June with seed usually maturing in late June or early July. The awns are curved, sharply bent in the middle, and about one inch long. The leaves are often rolled, thread-like, 4 to 12 inches long, smooth, with prominent veins above. Auricles are absent. The ligule is a ring of hairs, and the sheath is hairy at the margins. This species has rather deep, fibrous roots which in favorable situations may extend to a depth of 10 feet or more. Green needlegrass is very resistant to disease. It occurs only sparingly in most associations of native vegetation.

Required Growing Conditions

For current distribution, please consult the Plant Profile page for this species on the PLANTS Web site.

Habitat: This grass is an important native of the Northern Great Plains, and is found as far south as Arizona. Green needlegrass grows on medium to fine-textured soils in both the True Prairie and Mixed Prairie. On medium-textured soils, green needlegrass grows with western wheatgrass, needleandthread, and blue grama. On fine-textured soils, needleandthread drops out, and on even finer soils, blue grama decreases leaving green needlegrass and western wheatgrass as dominants. Green needlegrass naturally occurs on bottomlands, flat benches and overflow area along streams.

Cultivation and Care

This species is recommended for seeding mixes in the 12 to 18 inch precipitation zone. High dormancy is a characteristic of the seed of this species. Germinability improves for several years after harvest. Seedlings are slow in developing. Once established, they have good vigor. Green needlegrass has approximately 181,000 seeds per pound. The recommended seeding rate for western North and South Dakota is 6 PLS pounds per acre (25 pure live seeds per square foot). A full seeding rate for eastern North and South Dakota is 7.5 PLS pounds per acre (30 pure live seeds per square foot).

This species is often planted as part of a mix with other native grasses. If used as a component of a mix, it is necessary to adjust the seeding rate to the percent of mix desired. On most sites in the Dakotas where this species is adapted, it is seldom more than 30 percent of the mix. This species should be planted with equipment which provides for proper seed depth, a uniform seeding rate, and good seed to soil contact. If the seed has been processed to remove the awns, it can be seeded with other grasses in the small grain or wheatgrass box of a grass drill. The seedbed needs to be firm enough to allow seed to be planted only ½ to ¾ inch deep.

General Upkeep and Control

Hayland: Due to its early spring green-up green needlegrass is an important component of natural plant communities. This species is harvested for hay in native grass mixtures. In some areas, it makes up an appreciable portion of the yields of native hay from upland areas or from flats, on loamy to heavy clay soils. The hay is of good quality and is readily eaten by livestock. The time of peak forage production for green needlegrass is from mid to late August. In studies carried out in North and South Dakota, the five-year average for forage production varied from 700 lb/ac on a fine sandy loam to 1,100 lb/ac on a clay loam. Crude protein is good during the early growing season. A study at Hettinger, North Dakota, indicated a range from 19 percent on April 26, to 5 percent on August 24.

Pasture: Green needlegrass is not recommended for a solid seeding for grazing use. It is best used in pasture mixes. Growth begins in early spring, and cattle will seek it out. Growth continues in the fall when moisture conditions are favorable. It makes excellent recovery after grazing. It seems to stand up fairly well for winter grazing. This species will decrease under grazing use.

Seeds and Plant Production Seed production: Seed yields from green needlegrass fields vary from about 125 lb/ac on dry land to more than 250 lb/ac for irrigated fields. Older

Plant Basics
Growth Rate Rapid
General Type Graminoid
Growth Period Spring, Summer
Growth Duration Perennial
Lifespan Moderate
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 Intolerant
Height When Mature 2
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 Yes
Minimum Temperature -38
Soil Depth for Roots 14
Toxic to Nearby Plants No
Toxic to Livestock No
After-Harvest Regrowth Rate Rapid
After-Harvest Resprout Ability No
Responds to Coppicing No
Growth Requirements
pH Range 6.6–8.4 pH
Precipitation Range 15–15 inches/yr
Planting Density 0–0 indiv./acre
Soil Textures Fine, Medium
Soil Depth for Roots 14
Minimum Frost-Free Days 130 day(s)
Salinity Tolerance Medium
CaCO3 Tolerance High
Sustainability & Use
Leaf Retention No
Palatability Medium
Fire Resistant No
Causes Livestock Bloating None

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