Virginia Tech Weed Identification Guide

Bulbous Oatgrass or Bulbous Tall Oatgrass:

  Arrhenatherum elatius var. bulbosa

Weed Description:  Perennial, clump-forming grass that goes dormant during the summer and carries out it's life cycle during the winter months. Found throughout the southeastern United States primarily as a weed of winter small grains, landscapes, and turfgrass.
Leaves:  Leaves are rolled in the bud, without auricles, and have a membranous ligule approximately 1/2 to 1 mm long.  Leaf blades are approximately 10 mm wide and may reach 1 foot in length.  Leaf blades may be sparsely hairy above or without hairs (glabrous), but lower surfaces are usually completely glabrous.
oatgrass8-6b.jpg (152652 bytes) Stems:  Round, without hairs or only sparsely hairy with split, overlapping margins.
Roots:  Fibrous root system and bulbous fragments (pictured above) that are actually called corms.  These fragments allow for the vegetative reproduction and spread of this species.
Flowers:   Seedhead a narrow, shiny, erect or nodding, green or purplish panicle.
Identifying Characteristics:  Perennial, clump-forming grass that carries out it's life cycle during the winter.  Characteristic seedhead and bulbous roots (corms) also help to distinguish this weed from most other grass species.  oatgrass8-6.jpg (64384 bytes)