Pigeon Grass

Setaria species

Family: Poaceae.

Names:

Setaria is from the Latin seta, a bristle, and refers to the stiff bristles under the spikelets.
Slender Pigeon grass (Setaria parviflora was Setaria gracilis var. pauciseta or Setaria geniculata)
Foxtail (or Italian) Millet (Setaria italica (L.) P.Beauv.)
Whorled Pigeon grass (Setaria verticillata (L.) P.Beauv.)
Pale Pigeon grass (Setaria pumila ssp. pumila was Setaria glauca)
Green pigeon grass (Setaria viridis (L.) Beauv.)
Palm Grass (Setaria palmifolia (K.D.Koenig) Stapf)
South African Pigeon Grass (Setaria sphacelata (Schumach.) Stapf & C.E.Hubb.)
Pigeon Grass (Setaria surgens Stapf)

Summary:

Slender Pigeon Grass (Setaria parviflora was Setaria gracilis)
A 1.2 m high tufted spreading perennial grass with short knotty rhizomes. Inflorescence a cylindrical, spike-like panicle up to 100 mm long produced in summer. Spikelets solitary on each panicle branch, 4-12 yellow or purplish bristles below each spikelet.
A widespread weed of roadsides, disturbed, cultivated land from the coast to the plains in NSW, occurs also in Vic, SA, WA.
Whorled Pigeon Grass (Setaria verticillata)
A loosely tufted, almost hairless, annual, 10 cm to 1 m high. Stems bent near the base. Leaves thin, flat, slightly rough to touch, 50-300 mm long x 3-12 mm wide, a few scattered hairs. Emerging leaf rolled. Ligules very small ring of hairs. Collar prominent. Older leaves have a few hairs on the shoulder. No auricles. Leaf sheath flat, split, rolled with hairy margins and red at the back. Stems (culms) erect but usually bent at the lower nodes, hairless, unbranched or branched at the lower nodes, rough to touch below the seed head. Nodes brownish black, Inflorescence a dense spike-like panicle, 25-150 mm long x 4-24 mm wide (excluding bristles), green or purplish, erect or sometimes curved, produced in summer, with conspicuous bristles, near the base it is less dense where spikelets are arranged in whorls on short stalks (pedicels). Panicle branches 2-10 mm long. Axis and branches angled and rough. Spikelets green to pale green, 2-2.5 mm long, oblong with 2 florets. Upper floret bisexual, lower one sterile or male. 1-6 usually wavy bristles 4-8 mm long at the base of each spikelet with backward-pointing barbs that can catch onto animals and clothing. Glumes unequal, upper one equal to the spikelet, lower one half the length of the upper glume. Lemma of fertile floret almost smooth and as long as the glume. Paleas unequal, upper one almost as long as the lemma, lower one very small. Anthers almost 1 mm long. Seeds pale, dull, 1 mm long x 1 mm wide and remain tightly enclosed in the husks (palea and lemma). Seed germinates from spring to early summer.
A widespread weed of orchards vineyards, pastures. In NSW on the tablelands, slopes, plains. Also in QLD, Vic, SA.
Pale Pigeon Grass (Setaria pumila ssp. pumila)
An annual, tufted grass similar to Whorled pigeon grass with a denser inflorescence produced in summer. Has 6-8 bristles below spikelets, 2-3 times as long as the spikelets with forward pointing barbs.
Weed of disturbed areas, orchards, vineyards. Occurs in NSW coast and northern tablelands, slopes, plains, in Qld, Vic, SA, WA.
Green Pigeon Grass (Setaria viridis)
A smaller, loosely tufted annual with a shorter, dense, inflorescence, 20-50 mm long with 12-18 bristles with forward-pointing barbs per spikelet.
Weed of disturbed areas. Occurs in all mainland states. It is very similar to an probably a form of Whorled Pigeon Grass (Setaria verticillata).
Slender Panic (Setaria constricta)

Description:

Cotyledons:

One.

Leaves:

Blade - Flat or rolled.
Ligule - May be a rough rim of hairs.
Auricles -

Stems:

Flower stem - Erect.

Flower head:

Dense spike-like cylindrical panicle with single or clustered spikelets with one or more bristles underneath.

Flowers:

Spikelets -
Florets - 2 florets in each spikelet. Lower one male or empty upper one bisexual.
Glumes -
Palea - On lower floret it is membranous, on upper floret it is convex and finely pitted similar to lemma.
Lemma -
Stamens -
Anthers -

Fruit:

Seeds:

Oval. Enclosed in a hardened lemma and palea.

Roots:

Fibrous. S. gracilis has rhizomes.

Key Characters:

Biology

Life cycle:

Annual. S. gracilis is perennial

Physiology:

Reproduction:

Flowering times:

Seed Biology and Germination:

Vegetative Propagules:

Hybrids:

Allelopathy:

Population Dynamics and Dispersal:

Origin and History:

Various origins.
Setaria verticillata from the temperate areas of Europe and Asia and the tropical areas of America.

Distribution:

ACT, NSW, NT, QLD, SA, TAS, VIC, WA.
In WA there are 5 native and 7 introduced species.
There are 16 species in Australia.

Blue = Setaria gracilis. Red = Setaria pumila. White = Setaria verticillata. Yellow = Setaria viridis.
Courtesy Australia's Virtual Herbarium.

Habitats:

Climate:

Soil:

Plant Associations:

Significance:

Beneficial:

Fodder plants. Italian or Foxtail Millet (S. italica) is used as birdseed.

Detrimental:

Weeds.
Seeds of Whorled Pigeon grass tangle in wool and fur.

Toxicity:

May cause oxalate toxicity. Young growth appears to be more toxic. Lactating cows are more susceptible than other stock. Horses grazing Setaria for long periods may develop secondary nutritional disorders.
Fatal cases have been recorded from the November to February period.

Symptoms:

Cattle - Staggering gait in the hindquarters, Black or dark green diarrhoea, dry muzzle, lack of rumen movement, lethargy, loss of appetite, harsh coat, muscular tremors, some with rigid muscle spasms especially in facial muscles then collapse and lay down on their brisket and die.

Treatment:

Treat for oxalate toxicity, but the response is often poor or temporary.
Cattle - Injection by vein (or under skin) of 300-900 mL of 20% calcium borogluconate. Supplement this with 1-5 L of limewater or up to 50 g chalk in water or 250-500 g Epsom salts in water by mouth.
Provide alternative feed.
Don't graze young growth with lactating cows or unaccustomed or starving cattle.
Don't graze horses for long periods on Setaria pastures.
Avoid using high rates of potash or nitrogen on the pasture.
Plant cultivars with low toxicity ratings and develop a mixed sward.

Legislation:

Management and Control:

Thresholds:

Eradication strategies:

Herbicide resistance:

Biological Control:

Related plants:

South African Pigeon grass (Setaria sphacelata) is a rhizomatous pasture and hay grass.

Plants of similar appearance:

References:

Auld, B.A. and Medd R.W. (1992). Weeds. An illustrated botanical guide to the weeds of Australia. (Inkata Press, Melbourne). P57-58. Photos.

Black, J.M. (1965). Flora of South Australia. (Government Printer, Adelaide, South Australia). 231-233. Diagrams.

Burbidge, N.T. and Gray, M. (1970). Flora of the Australian Capital Territory. (Australian National University Press, Canberra). P66-68. Diagram.

Ciba Geigy 2

Cunningham, G.M., Mulham, W.E., Milthorpe, P.L. and Leigh, J.H. (1992). Plants of Western New South Wales. (Inkata Press, Melbourne). P138-139. Photos.

Everist, S.L. (1974). Poisonous Plants of Australia. (Angus and Robertson, Sydney). P345-347.

Lazarides, M. and Hince, B. (1993). CSIRO handbook of economic plants of Australia. (CSIRO, Melbourne). #1129.

Marchant, N.G., Wheeler, J.R., Rye, B.L., Bennett, E.M., Lander, N.S. and Macfarlane, T.D. (1987). Flora of the Perth Region. (Western Australian Herbarium, Department of Agriculture, Western Australia). 985-988.

McBarron, E.J. (1983). Poisonous plants. (Inkata Press, Melbourne). P19. Diagram.

Moerkerk, M.R. and Barnett A.G. (1998) More Crop Weeds. (R.G and F.J. Richardson, Melbourne). P60. Photos. Diagrams.

Acknowledgments:

Collated by HerbiGuide. Phone 08 98444064 or www.herbiguide.com.au for more information.