Nassella tenuissima

Overall Plant
Common Name: finestem needlegrass 
Type: Ornamental grass
Family: Poaceae
Native Range: Texas, New Mexico, Mexico, Argentina
Zone: 7 to 10
Height: 1.00 to 2.00 feet
Spread: 1.00 to 2.00 feet
Bloom Time: June to September
Bloom Description: Silvery yellow to light brown
Sun: Full sun to part shade
Water: Dry to medium
Maintenance: Low
Tolerate: Deer, Drought, Erosion, Clay Soil, Dry Soil, Shallow-Rocky Soil

Culture

Best grown in evenly moist to dry, well-draining, sandy, rich loams in full sun to partial shade. Tolerant of rocky and clayey soils as long as they are not overly moist. Tolerant of drought once established. Plants may go dormant during periods of summer drought. Cut the foliage back in late winter before new growth emerges in spring. Will readily spread by seed given the right conditions. Hardy in Zones 7-10 but generally grown as an annual in the St. Louis region.

Noteworthy Characteristics

Nassella tenuissima, commonly called Mexican feathergrass, is a finely textured, clumping, perennial grass native to open, rocky scrublands and woods on slopes and plateaus of the mountainous Trans-Pecos region of Texas west to southern New Mexico and south into central Mexico. There is also a disjunct, native population in Argentina and Chile. Mature clumps can reach 1-2' tall with an equal width. The light green leaves are very fine and upright. The foliage turns light brown in winter. Wispy, upright to gently arching panicles appear in summer bearing small, silvery yellow spikelets. The mature fruits have a thin, light brown, terminal bristle that can reach 2-4" long, creating a feather-like appearance. Synonymous with Stipa tenuissima.

The genus name Nassella comes from the Latin nassa, a narrow-necked fishing snare.

The specific epithet tenuissima comes from Latin and means "thinnest", most likely in reference to the narrow foliage.

The common name Mexican feathergrass refers to both part of the native range of this species and the feather-like appearance of the mature seedheads.

Problems

Aphids and leaf spot diseases are potential problems. Overly wet soils will lead to root or crown rot. Self-seeding can be problematic. Check local laws and recommendations before adding this plant to your landscape. Deer tend to avoid this plant.

Uses

Provides a fine textured accent for rock gardens and mixed borders. Suitable for mass planting, containers, and erosion control.