Urochloa texana

Species category

Weed

Common name

Texas signalgrass

Diagnostic characters

Planting unit

SpikeletSpikelet:
One or more florets that are subtended by a pair of bracts called glumes. Spikelets are pedicellate if located on a pedicle and sessile if attached directly to the rachis. Often spikelets with single florets have remnants of a second floret, usually a lemma.

Shape

OvalOval:
Broadly elliptic.

Size

  • Length 3.5–5 mm
  • Width 2–2.1 mm
  • Thickness 1.5–1.6 mm

Color

Light brown

Texture

The lemmaLemma:
One of two bracts of the grass floret; it is located on the side nearest the embryo and opposite the rachilla.
and paleaPalea:
One of the thin bracts of grass floret enclosing the fruit (caryopsis) that is located on the side opposite the embryo.
have transverseTransverse:
Set crosswise, crossing or at right angles.
rough ridges. The outer paleaPalea:
One of the thin bracts of grass floret enclosing the fruit (caryopsis) that is located on the side opposite the embryo.
margins are shiny.

Lemma

Hard

Palea

Hard

Other structures

Short and long glumesGlume:
The pair of chaffy bracts that occur at the base of a grass spikelet, often completely enclosing it.
and a sterile lemmaLemma:
One of two bracts of the grass floret; it is located on the side nearest the embryo and opposite the rachilla.
are present.

Identification notes

Seed unitSeed unit:
The structure usually regarded as a seed in planting practices and in commercial channels, consisting of a true seed with or without accessory structures, as defined in Section 2.6 of the AOSA Rules. See also true seed.
can be a spikeletSpikelet:
One or more florets that are subtended by a pair of bracts called glumes. Spikelets are pedicellate if located on a pedicle and sessile if attached directly to the rachis. Often spikelets with single florets have remnants of a second floret, usually a lemma.
, floretFloret:
A small flower in a clustered inflorescence (e.g., sunflower, grasses). In grasses, a floret consists of the lemma, palea, stamens, and pistil.
, or caryopsisCaryopsis:
The single-seeded fruit or grain of the grass family (Poaceae); the fruit wall (pericarp) is united with the seed coat (testa).
. SpikeletSpikelet:
One or more florets that are subtended by a pair of bracts called glumes. Spikelets are pedicellate if located on a pedicle and sessile if attached directly to the rachis. Often spikelets with single florets have remnants of a second floret, usually a lemma.
consists of (in order) a short clasping glumeGlume:
The pair of chaffy bracts that occur at the base of a grass spikelet, often completely enclosing it.
, a long glumeGlume:
The pair of chaffy bracts that occur at the base of a grass spikelet, often completely enclosing it.
, a long sterile lemmaLemma:
One of two bracts of the grass floret; it is located on the side nearest the embryo and opposite the rachilla.
, a hard fertile lemmaLemma:
One of two bracts of the grass floret; it is located on the side nearest the embryo and opposite the rachilla.
, a hard paleaPalea:
One of the thin bracts of grass floret enclosing the fruit (caryopsis) that is located on the side opposite the embryo.
, and finally the caryopsisCaryopsis:
The single-seeded fruit or grain of the grass family (Poaceae); the fruit wall (pericarp) is united with the seed coat (testa).
. PaleaPalea:
One of the thin bracts of grass floret enclosing the fruit (caryopsis) that is located on the side opposite the embryo.
is transversely rough between its margin ridges and shiny smooth outside the ridges. GlumesGlume:
The pair of chaffy bracts that occur at the base of a grass spikelet, often completely enclosing it.
and sterile lemmaLemma:
One of two bracts of the grass floret; it is located on the side nearest the embryo and opposite the rachilla.
are smooth and papery. GlumesGlume:
The pair of chaffy bracts that occur at the base of a grass spikelet, often completely enclosing it.
have strong longitudinal nerves.

Noxious weed seed categories

State Noxious Weed: Florida, Georgia, North Carolina

AOSA examination list

Not included

Nomenclature

Family

Poaceae

Valid name

Urochloa texana (Buckley) R.D. Webster

Synonyms

Brachiaria texana (Buckley) S.T. Blake 
Panicum texanum Buckley 

 Urochloa texana.  Spikelet with glumes and sterile lemma that are smooth and papery.
Urochloa texana. Spikelet with glumes and sterile lemma that are smooth and papery.
 Urochloa texana.  Spikelet with glumes that have strong longitudinal nerves.
Urochloa texana. Spikelet with glumes that have strong longitudinal nerves.
 Urochloa texana.  Spikelet where the palea is transversely rough between its margin ridges and shiny smooth outside the ridges. Photo by Julia Scher, USDA-APHIS-PPQ.
Urochloa texana. Spikelet where the palea is transversely rough between its margin ridges and shiny smooth outside the ridges. Photo by Julia Scher, USDA-APHIS-PPQ.
 Urochloa texana.  Spikelet where the palea is transversely rough between its margin ridges and shiny smooth outside the ridges. Photo by Julia Scher, USDA-APHIS-PPQ.
Urochloa texana. Spikelet where the palea is transversely rough between its margin ridges and shiny smooth outside the ridges. Photo by Julia Scher, USDA-APHIS-PPQ.