Scientific name(s)
Lolium rigidum
Strengths
- Vigorous growth.
- Drought tolerant.
- Tolerant of continuous grazing, heavy stocking, low soil fertility and some insect pests
Limitations
- Can cause Annual ryegrass toxicity.
- Can be a serious weed in field crops.
Plant description
Plant: a freely seeding, self-regenerating annual tussock grass. Strains highly variable re time of flowering, habit and tillering; habit varies from prostrate to erect. Fibrous root system. Flowers ~ mid October. Late types may be densely tillered, sprawling when mature.
Stem: up to 1 m high, red-purple colour at base extends upwards as plant matures; bent at nodes
Leaves: rolled in bud; dark green, hairless, flat; lower surface shiny and smooth; >2mm wide
Seedhead: a spike up to 300 mm long; spikelets edge-on to the rachis and have 10-12 florets, latterly flattened
Seeds: flatter and wider than other ryegrass spp. ~460,000/kg
Pasture type and use
A productive, nutritious feed, it is well suited to a short term pasture phase in the wheat sheep zone. Tends to decline after a few years pasture and maybe replaced by barley grass/brome grasses. Useful for hay and for improving the productivity of saline land.
Where it grows
Rainfall
360 - 635 mm (>250 mm in WA)
Soils
Suits a wide range of soils. Thrives on high fertility soil and on low-lying "crabhole" country in the Wimmera region, VIC., where rainfall 380-510 mm. Tolerant of moderately saline conditions.
Temperature
Adapted to areas S of 30°S latitude.
Establishment
Companion species
Legumes: sub. Clover, annual medics, lucerne
Sowing/planting rates as single species
1-3 kg/ha
Sowing/planting rates in mixtures
0.5-1 kg/ha
Sowing time
March/April
Inoculation
Not applicable
Fertiliser
Correct any nutrient deficiencies, especially N, P
Management
Maintenance fertliser
For optimum growth Olsen soil P > 15; but tolerates low fertility
Grazing/cutting
Cool season growth is maximised by autumn deferred grazing. Prolific growth in spring; remains edible during the seedhead phase and is valuable as standing hay. Undergrazing leads to dense population and a heavy demand on soil moisture; this weakens the stand. Phosphate fertilizer to encourage a legume contribution and grazing heavily in spring sustains a ryegrass legume pasture. Makes excellent hay/silage when grown with annual legumes.
Seed production
Seeds freely; matures rapidly in drought conditions.
Ability to spread
Will spread from seed
Weed potential
A serious, vigorous weed in crops; seed is stimulated to germinate following cultivation. Seed retained well in hay.
Major pests
No information.
Major diseases
Relatively resistant to root-rotting organisms.
Herbicide susceptibility
Propyzamide, Glyphosate. Some varieties have developed herbicide resistance.
Animal production
Feeding value
High
Palatability
Good, including seedhead.
Production potential
Reasonable winter growth; good spring growth
Livestock disorders/toxicity
Main host of organisms causing annual ryegrass toxicity, a serious neurotoxic disorder often with fatal outcomes. Both hay and pasture may be toxichttp://www.agric.wa.gov.au/content/pw/ah/dis/argt_index.htm http://www.agric.wa.gov.au/content/pw/ah/dis/fn002_2004.pdf
Cultivars
| Group | Cultivar | Seed source/Information |
| Cultivars non-resistant to ARGT | "Wimmera" - actually a highly variable ecotype | AusWest Seeds |
| Merriden | WA | |
| Cultivars resistant to ARGT causing nematode, Anguina funesta | Safeguard | Valley Seeds |
Guard | AusWest Seeds |
Denotes that this variety is protected by Plant Breeder's Rights Australia
Acknowledgements
DAFWA, SARDI
Author and date
K. Reed
September 2008
