Poa trivialis

Species category

Agricultural, Turf

Common name

rough bluegrass

Diagnostic characters

Planting unit

FloretFloret:
A small flower in a clustered inflorescence (e.g., sunflower, grasses). In grasses, a floret consists of the lemma, palea, stamens, and pistil.

Shape

Lanceolate 

Size

  • Length 2–2.5 mm 
  • Width 0.5–0.7 mm 
  • Thickness 0.5–0.7 mm 

Color

Uniform dark brown

Texture

Pubescence on lemmaLemma:
One of two bracts of the grass floret; it is located on the side nearest the embryo and opposite the rachilla.
nerves short and only on lower half

Lemma

Tight fitting; strong intermediate nerves.

Palea

Sharp medium crease; margin nerves minute and dense.

Other structures

Thin rachillaRachilla:
The axis of a spikelet.

Identification notes

In lateral view the dorsalDorsal:
Upper side or back of a seed or fruit.
side tends to be strongly arched, with the ventralVentral:
Adaxial; of the side of an organ facing the axis (compare dorsal).
side straight.

Noxious weed seed categories

State Noxious Weed: Delaware, Maryland, New Hampshire, New Jersey, Pennsylvania, Virginia, West Virginia 

AOSA examination list

Included

More information

For more information, see ISMA fact sheet.

Nomenclature

Family

Poaceae

Valid name

Poa trivialis L.

Synonyms

Poa attica Boiss. & Heldr.

From Left to Right: 1.  Poa annua  2.  Poa compressa  3 . Poa nemoralis  4.  Poa pratensis  5.  Poa trivialis . Florets with pubescence on the lower half of the lemma nerves.
From Left to Right: 1. Poa annua 2. Poa compressa 3. Poa nemoralis 4. Poa pratensis 5. Poa trivialis. Florets with pubescence on the lower half of the lemma nerves.
 Poa trivialis.  Florets with short pubescence on the lower half of the lemma nerves. 
Poa trivialis. Florets with short pubescence on the lower half of the lemma nerves. 
 Poa trivialis.  Florets with a dorsal side that tends to be strongly arched, while the ventral side is straight. 
Poa trivialis. Florets with a dorsal side that tends to be strongly arched, while the ventral side is straight.