Livestock disorders
None have been reported. Contains low levels of oxalate, so is not hazardous for horses.
Management
Premature grazing can severely damage a new Rhodes grass pasture as stock can up-root plants. Rhodes grass should not be grazed in the first year until the plants and runners are well anchored which may not occur until the autumn rains, as the stolons will only root into moist soils. Test the plants to see how well they are anchored before grazing.
Established stands can withstand periods of set-stocking, but heavy grazing can damage the stand. In more intensive systems, rotational grazing should result in higher production and better persistence.
In general, palatability is good but declines rapidly with maturity, so Rhodes grass should be grazed to prevent flowering. The digestibility of Rhodes grass varies widely, but is generally similar to other sub-tropical grasses at an equivalent growth stage.
Rhodes grass can survive fire, although hot fires can kill the small plants growing on stolon nodes.
Companion species
Rhodes grass can be grown with annual legumes like subterranean clover, burr medic and serradella on sandy, well-drained soils, or subterranean clover, balansa clover and slender serradella on winter-waterlogged soils. Graze the sward hard in late autumn to give the annual legumes an opportunity to establish.
Rhodes grass can be sown as a monoculture, but is usually sown in a mix with bunch grasses like panic grass. Rhodes grass can dominate when sown in a mixture due to its good seedling vigour and its ability to spread by runners. When sown as part of a mix, it will typically be the most productive species in the first two years.
Cultivars
There are a large number of Rhodes grass varieties and these can be separated in two main groups – diploid and tetraploid types – the latter having double the number of chromosomes.
Diploid types
These come from sub-tropical regions, are more robust and flower over a wide period as the flowering response is insensitive to day length. In general, they have superior frost tolerance, salt tolerance and drought tolerance than the tetraploid types.
‘Pioneer’ or common (public variety) is quite variable but is characterised as an early flowering, erect plant with moderate leafiness. It is widely naturalised in sub-tropical eastern Australia, but has been superseded by newer varieties.
‘Topcut’ (Plant Breeder's Rights - PBR) is a selection from Pioneer developed primarily for hay production, which is reported to be leafier, finer-stemmed and produce more dry matter.
'Salcut' (PBR) is a selection from Topcut Rhodes grass for improved plant growth and survival under saline conditions and then improved agronomic characteristics (fine stems, leafy growth habit).
‘Katambora’ (public variety) is mid-flowering and is characterised by strong stolon development, heavy seeding and drought tolerance. In Queensland, it is more persistent on low fertility soils than other cultivars.
‘Nemkat’ (public variety) is a selection from Katambora that has resistance to all the known root-knot nematodes in the north-Queensland tobacco growing areas. ‘Nemkat’ has had limited testing in WA.
‘Finecut’ (PBR) is a selection from Katambora developed primarily for hay production and is reported to be leafier, finer-stemmed and to produce more dry matter in Queensland.
'Gulfcut' (PBR) is a selection from Finecut Rhodes grass for improved plant growth and survival under saline conditions and then improved agronomic characteristics (fine stems, leafy growth habit).
'Reclaimer' (PBR) is a selection from Finecut Rhodes grass for improved plant growth and survival under saline conditions and then improved agronomic characteristics (fine stems, leafy growth habit).
'KG2' (PBR) and 'KP8' (PBR) are both selections from KP4 Rhodes grass for improved germination, growth and survival under saline conditions and then improved agronomic characteristics (late flowering, prostrate growth habit and stoloniferous growth).
Tetraploid (giant) types
Late flowering types from tropical regions that are tall (>1.8m) and have coarse leaves, stems and stolons. They are strongly stoloniferous, leafy, late flowering, drought-tolerant and have high dry matter production. Their main advantage is that they only flower late in the season (as they flower in response to short-day lengths), so feed quality is maintained for longer. However, when grown under optimal conditions and grazed regularly there is little if any difference in the animal intake or the digestibility of different types of Rhodes grass.
‘Callide’ (public variety) an introduction from Tanzania is widely grown in Australia.
'Sabre' (PBR) is a selection from 'Callide' Rhodes grass for improved germination, growth and survival under saline conditions and then improved agronomic characteristics (early flowering, leafy growth habit).
'Toro' (PBR) is a selection from 'Callide' Rhodes grass for improved germination, growth and survival under saline conditions and then improved agronomic characteristics (late flowering, leafy growth habit).
'Mariner' (PBR) is a selection from 'Samford' Rhodes grass for improved germination, growth and survival under saline conditions and then improved agronomic characteristics (late flowering, leafy growth habit).
It should be noted that the ‘salt tolerant’ Rhodes grass varieties that have recently become available were specifically developed for irrigation with brackish water and may not have the combination of salt and waterlogging tolerance required for most saline sites in the agricultural areas of WA.