Avena sativa (Cultivated Oats)

Plant Info
Also known as: Common Oats
Genus:Avena
Family:Poaceae (Grass)
Life cycle:annual
Origin:Eurasia
Habitat:part shade, sun; moist to dry soil; roadsides, along railroads, fields, waste places
Fruiting season:June - September
Plant height:14 to 40 inches
Wetland Indicator Status:GP: FACU MW: UPL NCNE: UPL
MN county distribution (click map to enlarge):Minnesota county distribution map
National distribution (click map to enlarge):National distribution map

Pick an image for a larger view. See the glossary for icon descriptions.

Detailed Information

Flower: Flower shape: indistinct Cluster type: panicle

[photo of panicle] Open panicle 6 to 16 inches long, more or less erect and pyramidal in outline, the branches widely separated, ascending to spreading to somewhat drooping, with a few to several spikelets (flower clusters) per branch. Spikelets are slender-stalked, dangling on one side of the branch, lance-elliptic to V-shaped in outline, somewhat flattened, 20 to 32 mm (to ~1¼ inch) long, usually with 2 florets, occasionally 1 or 3.

[close-up of spikelet] At the base of a spikelet is a pair of bracts (glumes), both hairless, thin especially near the tip, 7 to 9-veined, tapering to a sharply pointed tip, 20 to 25 mm long and longer than the group of florets, the lower glume as long as the upper glume or nearly so. Surrounding a floret is a pair of bracts (lemma and palea), the lemmas thicker than the glumes, hairless, 12 to 18 mm long, 7 to 9-veined, the veins mostly obscure except at the tip, the tip blunt with minute teeth along the edge, usually awnless or sometimes with a straight awn 15 to 30 mm long arising from near the middle of the back; the palea is slightly shorter than the lemma, 2-veined with a fringe of fine hairs along the veins. The thickened base of the floret (callus) and the stalk between florets (rachilla) are usually hairless, sometimes sparsely hairy.

Leaves and stems: Leaf attachment: alternate Leaf type: simple

[photo of sheath, ligule and node] Leaf blades are flat, 5 to 16 inches long, 5 to 16 mm (to ~2/3 inch) wide, the surfaces slightly rough. Sheaths are hairless, smooth to slightly rough. The ligule (membrane where the leaf joins the sheath) is 2 to 8 mm long, straight across to pointed at the tip and lacks a fringe of hairs. Nodes are smooth. Stems are single or a few from the base in a loose clump, mostly erect, hairless, and may be branched from the base.

Fruit: Fruit type: seed without plume

[photo of maturing florets] Florets turn straw-colored to light brown when mature and typically do not drop off, the entire spikelet persisting on the branch. Grains (seeds) are somewhat flattened, elliptic, 4 to 9 mm long, light brown and longitudinally grooved.

Notes:

Oats is a Eurasian introduction that has been cultivated around the world. It occasionally escapes cultivation but rarely persists more than a few years. More often it is used as a cover crop for roadside plantings and restoration areas. There are several forms of Avena sativa, some growing as tall as 6 feet, have up to 7 florets per spikelet, and/or sheds its grains at maturity leaving the rest of the florets on the stalk. Spring-sown forms are most common in the Upper Midwest; winter-sown forms are more common in the south and on the Pacific coast.

Cultivated Oats is fairly easy to recognize with the loose panicle of dangling spikelets; spikelets are usually 2-flowered, the large glumes (to 1¼ inch long) often hiding the much smaller florets; glumes are strongly veined and lack awns; lemmas usually also lack awns but when present are more or less straight and arise from the middle of the back, lemma veins are mostly distinct only at the tip; the callus and rachilla are both usually hairless, sometimes sparsely hairy. It is similar to the related Wild Oats (Avena fatua), which has long hairs on the lemma, callus and rachilla, and lemmas have a bent awn 20 to 42 mm long.

Please visit our sponsors

  • Minnesota Native Plant Society

Where to buy native seed and plants ↓

Map of native plant purveyors in the upper midwest

  • Minnesota Native Landscapes - Your Ecological Problem Solvers
  • Natural Shore Technologies - Using science to improve land and water
  • Itasca Ladyslipper Farm - Native orchids, container grown
  • Prairie Restorations - Bringing people together with the land
  • Landscape Alternatives - Distinctive Native Plants since 1986!

More photos

Photos by K. Chayka taken in Aitkin County. Photos by Peter M. Dziuk taken in Aitkin County and in Alabama.

Comments

Have you seen this plant in Minnesota, or have any other comments about it?

Post a comment

Note: All comments are moderated before posting to keep the riff-raff out. An email address is required, but will not be posted—it will only be used for information exchange between the 2 of us (if needed) and will never be given to a 3rd party without your express permission.

For info on subjects other than plant identification (gardening, invasive species control, edible plants, etc.), please check the links and invasive species pages for additional resources.



(required)




Note: Comments or information about plants outside of Minnesota and neighboring states may not be posted because Id like to keep the focus of this web site centered on Minnesota. Thanks for your understanding.