SafePlants

Henderson's Needlegrass (Achnatherum hendersonii)

Henderson's Needlegrass, scientifically known as Achnatherum hendersonii (Vasey) Barkworth, is a perennial graminoid belonging to the genus Achnatherum. It is also referred to as Henderson's Ricegrass.

Taxonomy and Nomenclature

• Scientific Name: Achnatherum hendersonii (Vasey) Barkworth
• Common Name: Henderson's Needlegrass
• Family: Poaceae (Grass Family)
• Rank: Species
• Synonyms:
  • Oryzopsis hendersonii Vasey
  • Stipa (implied but incomplete reference in text)

Distribution and Habitat

• Henderson's Needlegrass is found in regional geographical ranges, including:
  • Idaho
  • New Mexico
  • Southwestern United States
• It can be found in scabland habitats, such as those in the Ochoco National Forest.
• It sometimes grows along the periphery of riparian vegetation.

Morphological Characteristics and Growth Habits

• It is a perennial plant.
• It grows in a graminoid habit.
• It exhibits a tightly cespitose growth pattern (forming dense tufts or clumps).
• Some varieties are shortly rhizomatous.

Ecological Role

• Henderson's Needlegrass shares scabland habitats with species such as scabland sagebrush, pine bluegrass, rock onion, bitterroot, and wormleaf stonecrop.
• Its presence is considered in the designation of RHCA (Riparian Habitat Conservation Area) crossings to avoid damaging its habitat.
• It can be associated with other plants like Peck's Mariposa lily, Botrychium species, Blandow's bog moss, and Tomentypnum moss in certain habitats.

Related Species

• Wallowa Needlegrass (Achnatherum wallowaense)
• Letterman's Needlegrass (Achnatherum lettermanii), also known by synonyms Stipa lettermanii and Stipa.
• Lemmon's Needlegrass (Achnatherum lemmonii)

Further Information

• USDA Plants Database: Provides a Species Code (ACHE10) for Henderson's Needlegrass.
• Encyclopedia of Life: Lists Henderson's Needlegrass under the family Poaceae.
• FNA (Flora of North America)