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 gracilis Kunth. var. pauciseta (Desv.) B.Simon [was Setaria geniculata (Lam.) P.Beauv.])

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.)

Summary:

Slender Pigeon Grass (Setaria gracilis)

A 1.2m 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. 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, rolled with hairy margins and a red base. Inflorescence a dense spike-like panicle to 120mm long, green or purplish, produced in summer, with conspicuous bristles, near the base is less dense where spikelets arranged in whorls. One (occasionally 2) bristle 4-8mm long at the base of each spikelet with backward-pointing barbs that can catch onto animals and clothing. Seeds pale, dull, 1 mm long by 1 mm wide and remain enclosed in the husks. 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 PigeonSetaria verticillata

Description:

Cotyledons:

One.

Leaves:

Blade -

Ligule - Flat or rolled, may be a rough rim of hairs.

Auricles -

Stem leaves -

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.

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.

Habitats:

Climate:

Soil:

Plant Associations:

Significance:

Beneficial:

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

Detrimental:

Weeds.

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 spasm 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.