Leymus racemosus subsp. racemosus

Species category

Revegetation or Rangeland

Common name

mammoth wildrye

Diagnostic characters

Planting unit

CaryopsisCaryopsis:
The single-seeded fruit or grain of the grass family (Poaceae); the fruit wall (pericarp) is united with the seed coat (testa).

Shape

Lanceolate

Size

Length 9–12 mm
Width 2–3 mm
Thickness 0.3–0.4 mm

Color

Yellowish-brown

Texture

RachillaRachilla:
The axis of a spikelet.
is copiously pubescentPubescent:
Having hairs.
.

Lemma

Awnless; widest on basalBasal:
The base of the fruit or seed opposite the apical end.
end; hairy at margins of basalBasal:
The base of the fruit or seed opposite the apical end.
half.

Palea

Same length as lemmaLemma:
One of two bracts of the grass floret; it is located on the side nearest the embryo and opposite the rachilla.
; fully exposed; margins inrolled at basalBasal:
The base of the fruit or seed opposite the apical end.
half.

Other structures

RachillaRachilla:
The axis of a spikelet.
is wide at apexApical:
The distal end of the fruit or seed away from the point of attachment or attachment scar.
and narrow at base; groove over callusCallus:
The hard base of grass florets or spikelets, just above the point of disarticulation.
.

Identification notes

CaryopsisCaryopsis:
The single-seeded fruit or grain of the grass family (Poaceae); the fruit wall (pericarp) is united with the seed coat (testa).
is very hairy on the rachillaRachilla:
The axis of a spikelet.
and on lateral sides of the lemmaLemma:
One of two bracts of the grass floret; it is located on the side nearest the embryo and opposite the rachilla.
on the basalBasal:
The base of the fruit or seed opposite the apical end.
half. LemmaLemma:
One of two bracts of the grass floret; it is located on the side nearest the embryo and opposite the rachilla.
is awnless, with a lateral groove just above the callusCallus:
The hard base of grass florets or spikelets, just above the point of disarticulation.
. The upper half of the lemmaLemma:
One of two bracts of the grass floret; it is located on the side nearest the embryo and opposite the rachilla.
has five nerves that converge at the apexApical:
The distal end of the fruit or seed away from the point of attachment or attachment scar.
.

Noxious weed seed categories

Not listed

AOSA examination list

Not included

Nomenclature

Family

Poaceae

Valid name

Leymus racemosus subsp. racemosus (Lam.) Tzvelev

Synonyms

Elymus arenarius L. var. giganteus (Vahl) Schmalh.
Elymus giganteus Vahl
Elymus racemosus Lam.
Leymus giganteus (Vahl) Pilg.

Leymus racemosus ssp. racemosus. The rachilla is wide at the apex and narrow at the base, with a groove over the callus.

Leymus racemosus ssp. racemosus. The caryopsis is very hairy on the rachilla and on the lateral sides of the lemma on the basal half.

SeedImages