Bulbous oat grass is a cool-season clumping grass in the Poaceae family native to Europe, western Asia and northern Africa. It can be found growing in prairies, along roadsides, and in uncultivated fields. The genus name is derived from the Greek term 'arren', referring to the bristly awns on the male flowers. Species epithet means 'tall', alluding to the foliage. The subspecies epithet 'bulbosum' means 'bulbous', describing the swollen corms at the base of the plant It grows up to 4 feet tall and prefers cool nights and dry summers, becoming diseased or going dormant in heat but will produce new foliage in fall. It prefers sun to partial shade in moist, well-drained soil but tolerates poor and dry soil. It is drought-tolerant, but it doesn't withstand foot traffic. Prune old growth in spring to encourage new shoots. The grass develops bulbous storage organs at the base of its stems and grows in a mound of fine to medium-textured leaves.Flowers best in cooler summers with panicles of brownish flowers. It is considered a weed of cultivated fields as tilling spreads the bulbs further. This grass can be grown as forage for cattle. It can also be used in the garden border to add structure and interest or in a container. The cultivar 'Variegatum' has variegated leaves, is more compact and may be easier to find. Insects, Diseases, and Other Plant Problems: No significant problems. Watch for rust.
Curated pairwise relationships between this plant and others in the library — who feeds
whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.
No curated interactions recorded for this species yet.
Also noted by NC State
Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell
apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.