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spike bur grass, spike burr grass

Australian bur grass

Habit Plants annual. Plants annual.
Culms

(2)3.5-45 cm.

10-45 cm.

Panicles

(1)2-13 cm long, (3)4-8 mm wide;

rachises pubescent;

branches (0.5)0.7-2.7 mm, pubescent, with 2(3) spikelets, axes occasionally extending past the distal spikelets;

proximal internodes 0.2-0.6(0.7) mm, shorter than the second internodes.

(4.5)6-13.5 cm long, 7-9 mm wide;

rachises pubescent;

branches 0.7-1.2 mm, pubescent, with 2(3) spikelets, axes rarely extending past the distal spikelets;

proximal internodes 0.6-1 mm, usually 2-3 (or more) times longer than the second internodes.

Caryopses

(0.9)1.2-2 mm long, 0.4-0.8 mm wide.

1.2-1.5 mm long, 0.6 mm wide.

Ligules

0.5-1 mm;

blades (0.5)0.7-8.5 cm long, 1.2-5 mm wide, glabrous.

0.5-1 mm;

blades (0.7)3.5-7 cm long, (1.5)2-4 mm wide, surfaces glabrous.

Proximal

spikelets (1.8)2^.3 mm;

second spikelets (0.8)1-3.9 mm, sometimes sterile.

spikelets 3.1-3.5 mm;

second spikelets 2.7-3.3 mm.

Lower

glumes 0.1-0.6 mm, membranous, minutely pubescent;

upper glumes 1.8-4.3 mm, minutely pubescent, 5-veined, rarely with 1-2 additional veins adjacent to the midvein;

glume projections (4)6-14, in 5 rows, (0.2)0.3-1 mm, uncinate;

lemmas (1.5)1.8-3.1 mm, sparsely pubescent on the back, midveins occasionally excurrent to 0.6 mm;

paleas (1.3)1.5-2.4 mm;

anthers 3, 0.4-0.6 mm, yellow, occasionally purple-or green-tinged.

glumes absent or to 0.4 mm, glabrous;

upper glumes 3.1-3.5 mm, minutely pubescent, 5-veined;

glume projections 7-10, in 5 rows, 0.2-0.8 mm, uncinate;

lemmas 2.4-2.6 mm, sparsely pubescent on the back, midveins sometimes excurrent to 0.2 mm;

paleas 2-2.2 mm;

anthers 3, 0.4-0.5 mm, yellow.

2n

= 20.

= unknown.

Tragus berteronianus

Tragus australianus

Distribution
from FNA
AZ; MA; ME; NM; NY; SC; TX; VA; HI; PR; Virgin Islands
[WildflowerSearch map]
[BONAP county map]
from FNA
SC
[BONAP county map]
Discussion

Tragus berteronianus is native to Africa and Asia, and is now established in Arizona, New Mexico, and Texas. It was collected in Maine, Massachusetts, New York, and Virginia in the nineteenth century, and Virginia in 1959.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Tragus australianus is native to Australia, where it becomes established rapidly on disturbed or bare soil after summer rains. In the Western Hemisphere, it is known from Berkeley and Florence counties, South Carolina, and Argentina.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 25, p. 280. FNA vol. 25.
Parent taxa Poaceae > subfam. Chloridoideae > tribe Cynodonteae > Tragus Poaceae > subfam. Chloridoideae > tribe Cynodonteae > Tragus
Sibling taxa
T. australianus, T. heptaneuron, T. racemosus
T. berteronianus, T. heptaneuron, T. racemosus
Name authority Schult. S.T. Blake
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