A softly hairy, tufted perennial grass with grey to pink, soft seed heads that are initially narrow and become open with age.
Description:
Cotyledons:
One
Leaves:
Alternate. Emerging leaf rolled in the bud.
Blade - Green to grey green, 40-200 mm long by 3-10 mm wide, flat, lax, parallel sided narrowing to a fine point. Softly hairy all over.
Ligule - 1-4 mm long, membranous, truncate(cut off squarely) and jagged.
Auricles - None.
Sheath - Rounded on the back. Bent back, soft hairs. Often has red stripes. Rolled and overlapping.
Stems:
Erect or ascending, tufted or many from the base, unbranched below the flower head, up to 1000 mm tall, slender to stout, often bent at the lower nodes. 2-5 hairy nodes. Stems softly hairy, often hairless in the upper half or rarely hairless.
Flower head:
Erect or nodding, pale green to pink-purple to grey-white, initially compact becoming more open with time, 30-200 mm long, 10-80 mm wide, oval, interrupted. Closely divided, hairy branches. Compound panicle with crowded, single spikelets. Flower head often remains partly enclosed in the leaf sheath.
Flowers:
Spikelets - Oblong to elliptic, flattened, 4-6 mm long, 2 flowered.
Florets - Firm and shining. first one is bisexual and awnless, second is usually male with a curved 2 mm awn on the back. Both on a short, 1-4 mm long, hairy stalk (pedicel).
Glumes - 4-5 mm long, white with pink or red tinge, boat shaped, keeled, thin, papery, hairy, similar lengths. Stiffly hairy on the keels and nerves.
First one is 3.5-5 mm long, narrowly egg shaped, one nerved with an acute tip and a tiny point.
Second is 4.5-6 mm long, egg shaped, 3 nerved with an obtuse tip with a tiny point or 1 mm long awn .
Palea - 2 keels, shorter than or equal to its lemma.
Lemma - 2-2.5 mm long, shorter than glume, shiny, 3-5 nerved, keeled upwards, obtuse tip.
Lower one fertile, boat shaped, awnless, same length as its palea.
Upper one narrower, with stamens, longer than its palea and often with a 2 mm long awn on their back, near the top, that curves as it dries.
Stamens -
Anthers -
Breaks below the glumes. Spikelet falls as a whole.
Fruit:
Seeds:
Yellow-brown with a darker tip. Oval to tear shaped. Surface shiny, flattened, grooved and hairy.
Roots:
Fibrous.
Key Characters:
Upper glume with awn to 2 mm long. Lower glume acute or mucronate. Flower head pink to purple.
Biology:
Life cycle:
Perennial. Germinates in autumn and winter. Flowers in spring to summer.
Physiology:
Tolerates waterlogging and acidity.
Low palatability which becomes poorer as the plant matures. Heavy grazing or slashing in spring before flowering can improve palatability.
Digestibility and protein levels are similar to Perennial Ryegrass and Phalaris.
Less drought tolerant than Phalaris and Cocksfoot.
Reproduction:
By seed.
Flowering times:
Mainly August to December but may occur at any time in SA.
Spring to early summer in western NSW.
Spring and summer in WA.
October to January with occasional flowers in August in Perth.
Seed Biology and Germination:
Vegetative Propagules:
Hybrids:
Cultivars are used as commercial pasture grasses in NZ and UK.
Allelopathy:
Clover germination tends to be poor in Yorkshire Fog stubble.
Population Dynamics and Dispersal:
Spread by seed. Grows in wet areas and tends to disappear on dry exposed slopes. Invades areas destabilised by over grazing, cultivation, inundation, drought or acidity. Low palatability tends to result in companion species being over grazed allowing Yorkshire fog to invade these areas. It tends to dominate in low stocking rate pasture.
Origin and History:
Temperate Europe and Asia.
Distribution:
ACT, NSW, QLD, SA, TAS, VIC, WA.
Habitats:
Climate:
High winter rainfall areas.
Soil:
Freshwater wetlands.
Plant Associations:
Significance:
Beneficial:
Fodder but not very palatable. Under heavy grazing pressure at 20 dse/ha, it can be a productive pasture.
Detrimental:
Weed of pastures, irrigated areas, roadsides, gardens, water courses, perennial crops, grass lands and wetlands.
Toxicity:
Not recorded as toxic.
Legislation:
None.
Management and Control:
Increase stocking rate on the pasture to reduce selective grazing by stock. Fence of infested areas to force stock to graze it. Grazing with cattle rather than sheep is more effective because they are tend to leave more of the low growing clovers.
Heavy grazing or slashing in spring before flowering can improve palatability.
Slashing or cutting for silage in spring should be conducted if stock numbers are insufficient to keep it well grazed.
Yorkshire Fog nutritional data
Stage
Crude protein (%)
Metabolisable energy (MJ/kg)
Digestible dry matter (%)
Late vegetative
16.9
10.2
62.9
Flowering
7.3
8.9
59.1
Late flowering (unslashed)
7.2
7.6
50.8
Late flowering (slashed)
14.1
8.7
58.1
Regrowth (unslashed)
5.8
6.1
40.9
Regrowth (slashed)
23.7
10.6
70.4
Silage
12.8
9.0
50
courtesy NSW Agriculture, Peter Simpson.
Characteristics of common perennial grasses.
Species
Autumn growth
Winter growth
Spring growth
Waterlog tolerance
Acidity tolerance
Persistence
Cocksfoot
lo-med
lo-med
med-hi
low-med
hi
med
Fescue
med
lo-med
med-hi
hi
hi
lo-med
Phalaris
med
lo-med
med-hi
hi
lo-med
hi
Ryegrass
med
med
med-hi
med-hi
med
lo-med
Yorkshire Fog
med
med
med-hi
hi
hi
med-hi
Courtesy NSW Agriculture, Peter Simpson.
Thresholds:
Eradication strategies:
Spray with glyphosate in autumn or spring when plants are actively growing then cultivate 2 weeks later. Repeat as necessary. Use a wetting agent.
Planting a hay crop and spraying after hay cutting helps reduce seed banks. (Spraying and replanting to pasture species usually fails).
Yorkshire Fog normally reinvades and establishes to similar levels in 3-6 years if the grazing management of the paddock remains similar to that before control.
Herbicide resistance:
Biological Control:
Related plants:
Creeping Fog (Holcus mollis) is similar but has rhizomes and a creeping habit.
Annual Fog (Holcus setiger) is similar but is annual, has an awn on both glumes, the awn is more than 2 mm long and the flower head is whiter.
Plants of similar appearance:
Grasses.
References:
Auld, B.A. and Medd R.W. (1992). Weeds. An illustrated botanical guide to the weeds of Australia. (Inkata Press, Melbourne). P47.
Black, J.M. (1965). Flora of South Australia. (Government Printer, Adelaide, South Australia). P104. Diagram.
Buckley, D. (2000) Yorkshire fog grass provides hardy alternative. Farming Ahead, September 2000. Kondinin Group.
Burbidge, N.T. and Gray, M. (1970). Flora of the Australian Capital Territory. (Australian National University Press, Canberra). P33. Diagram.
Cunningham, G.M., Mulham, W.E., Milthorpe, P.L. and Leigh, J.H. (1992). Plants of Western New South Wales. (Inkata Press, Melbourne). P110. Photo.
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). P56. Photo.
Lamp, C. and Collet, F. (1990). A Field Guide to Weeds in Australia. (Inkata Press, Melbourne).
Lazarides, M. and Hince, B. (1993). CSIRO handbook of economic plants of Australia. (CSIRO, Melbourne). #651.1.
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). P963.
Paterson, J.G. (1977). Grasses in South Western Australia. (Western Australian Department of Agriculture Bulletin 4007). P54.