A hairy, tufted annual grass, 20-80 cm tall, with single spikelets on an open head that is about half the size of the plant and has its base enclosed in the top sheath until maturity when it breaks off and blows around.
Description:
Cotyledons:
One
Leaves:
Light green, sometime tinged with purple. Emerging leaf rolled in the bud.
Blade - Flat, parallel sided, tapering to a fine point, 90-250 mm long by 5-18 mm wide,. thin, often with a wavy edge. Conspicuous midrib. Both sides with scattered wart based hairs. It sometimes has purple stripes.
Ligule - Membranous, fringed with many hairs ~1 mm long.
Auricles - None.
Collar - hairy.
Sheath - Often becoming loose, wart based hairs. Obvious veins, striped, ribbed. Rolled and overlapping. On the seedling the sheath is often smooth in the basal area and hairy in the upper part. Hairs 1.5-2.5 mm long.
Stems:
Tufted, erect or angled upwards at the nodes, 200-800 tall, simple or branching at the lower nodes or occasionally at the upper nodes. Hairy to almost hairless. Usually angled at the nodes. Usually has about 4 bearded nodes.
Flower head:
Loose, large, wide, compound, open, much branched panicle, 150-400 mm long and wide. Initially enclosed in top leaf sheath, with the base remaining in the sheath until near maturity. Branches often in rings near the base and single near the top. Branches initially rather upright and spreading with age. Often half to two thirds the length of the plant. Sparsely hairy.
Spikelets are single on 8-20 mm stalks that are rough to touch.
Flowers:
Spikelets - Straw coloured, 2-3 mm long, oval, tapering to an acute tip. pale green Hairless. 2 flowered.
Florets - Lower one sterile. Upper one fertile,
2-2.2 mm long, smooth, glossy, hard and brittle. Pale then turning yellow to dark brown.
Glumes -Lower one is les than half the length of the spikelet, triangular, 1 mm long, 3-5 ribbed with a pointed tip. Upper one is as long as the spikelet, 2 mm long, 5-9 ribbed, convex on the back and has a pointed tip.
Palea - None on the lower floret. On upper floret it is hard, thin brittle, shiny with infolded edges and hairless .
Lemma - of lower floret, same length as upper glume, encloses the palea. Second one becomes hard, smooth and shining. Lemma of upper floret, pale, oval, 1.8-2 mm long by 0.8 mm wide, flat to convex, hard, thin, brittle, shiny, pointed tip and hairless.
Stamens -
Anthers -
Fruit:
The whole seed head breaks off the plant at maturity. Seed structure breaks off below the glumes and falls entire.
Seeds:
Light to dark brown, shiny small grain.
Roots:
Fibrous and shallow.
Key Characters:
Annual.
Leaf blade 5-15 mm wide.
Ligule membranous, ciliate.
Nodes bearded (maybe not in WA samples)
Inflorescence a many spike like raceme, enclosed at the base until maturity, more than 100 mm long.
Pedicels 8-20 mm long
Spikelets solitary, without an involucre, disarticulates below the glumes, less than 4 mm long.
Upper floret bisexual.
Lower floret sterile.
Upper glumes about as long as the spikelet, glabrous, acute.
Lower glume less than half the length of the spikelet, shorter than upper glume, glabrous
Lemma similar texture to glume.
No appendage below palea.
From John Black, Flora of SA, E.M. Bennet, Flora of the Perth Region. Nancy Burbidge, Flora of the ACT.
Panicle usually more than 100 mm long and fully exserted when mature. No appendage below the palea. Spikelets to 4 mm long. First glume about half the length of the spikelet with an acute tip. Leaves with at least some hairs. Nodes bearded. Leaf blade 2-5 mm wide.
Biology:
Life cycle:
Annual. Germinates in spring, grows over summer and sets seed in late summer to autumn.
Physiology:
Reproduction:
By seed.
Flowering times:
January to March with some in November and May in Perth.
January to March in SA.
Summer to autumn in western NSW.
January to March in SA.
Seed Biology and Germination:
Produces large quantities of seed.
Vegetative Propagules:
None.
Hybrids:
Allelopathy:
Population Dynamics and Dispersal:
Spread seed.
Origin and History:
Native to North America.
Distribution:
ACT, NSW, SA, TAS, VIC, WA.
Habitats:
Climate:
Temperate. Mediterranean.
Soil:
Cultivated and uncultivated areas.
Heavy clay soils in depressions and gilgais.
Red earths. Duplex soils. Black soils
Flood plain areas.
Dry and moist soils.
Plant Associations:
Significance:
Beneficial:
Poor forage producer. Palatable when young but it becomes rather woody with age.
Detrimental:
Weed of roadsides, gardens, disturbed and cultivated areas. Minor weed of pastures.
Toxicity:
Not recorded as toxic but related species cause photosensitization or sunburn in stock.
Legislation:
None.
Management and Control:
Thresholds:
Eradication strategies:
Apply glyphosate in autumn and spring.
Herbicide resistance:
Biological Control:
Related plants:
Black seeded Panic (Panicum bisulcatum)
Blue Panic (Panicum antidotale)
Bulbous Panic (Panicum bulbosum)
Coolah grass (Panicum coloratum)
Dwarf Panic (Panicum pygmaeum)
Gilgai grass (Panicum subxerophilum)
Green Panic (Panicum maximum var. trichoglume)
Guinea grass (Panicum maximum)
Hairy Panic (Panicum effusum)
Millet Panic (Panicum miliaceum)
Native Panic (Panicum buncei)
Native Millet (Panicum decompositum)
Pepper grass (Panicum laevinode)
Rigid Panic (Panicum prolutum)
Swamp Panic (Panicum paludosum)
Sweet Panic (Panicum gilvum)
Torpedo grass (Panicum repens)
Two coloured Panic (Panicum simile)
Whitewater Panic (Panicum obseptum)
Witchgrass (Panicum capillare)
Yabila grass (Panicum queenslandicum)
Panicum luzonense
Panicum novemnerve
Plants of similar appearance:
Hairy Panic (Panicum effusum) is very similar but is perennial with narrower leaf blades 2-5 mm wide and the seed head is not enclosed in the top sheath when young and the spikelets are paired towards the ends of the branches.
Grasses.
References:
Black, J.M. (1965). Flora of South Australia. (Government Printer, Adelaide, South Australia). P222.
Bodkin, F. (1986). Encyclopaedia Botanica. (Angus and Robertson, Australia).
Burbidge, N.T. and Gray, M. (1970). Flora of the Australian Capital Territory. (Australian National University Press, Canberra). P66.
Cunningham, G.M., Mulham, W.E., Milthorpe, P.L. and Leigh, J.H. (1992). Plants of Western New South Wales. (Inkata Press, Melbourne). P118.
Everist, S.L. (1974). Poisonous Plants of Australia. (Angus and Robertson, Sydney).
Hussey, B.M.J., Keighery, G.J., Cousens, R.D., Dodd, J. and Lloyd, S.G. (1997). Western Weeds. A guide to the weeds of Western Australia. (Plant Protection Society of Western Australia, Perth, Western Australia). P60.
Lamp, C. and Collet, F. (1990). A Field Guide to Weeds in Australia. (Inkata Press, Melbourne).
Lazarides, M. and Cowley, K. and Hohnen, P. (1997). CSIRO handbook of Australian Weeds. (CSIRO, Melbourne). #739.4.
Marchant et al (1987). Flora of the Perth Region. (Western Australian Herbarium, Department of Agriculture, Western Australia). P971.
Moerkerk, M.R. and Barnett A.G. (1998) More Crop Weeds. (R.G and F.J. Richardson, Melbourne). P38. Photos. Diagrams.
Stucky, J.M. (1981). Identifying Seedling and Mature Weeds Common in the Southeastern United States. (The North Carolina Agricultural Research Service and The North Carolina Agricultural Extension Service, North Carolina State University, Raleigh) P182. Photos.
Acknowledgments:
Collated by HerbiGuide. Phone 08 98444064 or www.herbiguide.com.au for more information.