Newer varieties of perennial ryegrass will allow for longer or shorter growing seasons, depending on where the pasture is to be sown.
Well-drained crests or valley floors will hold moisture for longer.
Most dryland pasture systems for sheep and beef cattle in south-west Victoria are based on summer dormant cultivars of perennial ryegrass or phalaris with subterranean clover.
Perennial ryegrass has a number of advantages including easy management, high nutritive value and it can tolerate a range of grazing practices.
However, perennial ryegrass also has a number of disadvantages including a shallow root system, spring-dominant growth pattern, low summer productivity and often poor persistence, particularly in hot and dry summers. Phalaris has deeper roots so it is more persistent but is used less as rainfall increases towards the coast.
Perennial ryegrass is easier to establish, gets away faster in autumn and is easier to maintain feed quality in spring.
The old cultivars of perennial ryegrass and phalaris are not as productive as the newer cultivars but they are still being sown as they are considered more forgiving for grazing upon. Nwer varieties of perennial ryegrass contain novel endophytes which is a helpful fungus that increases plant persistence while reducing perennial ryegrass staggers.
This research into endophytes is underway at the Dairy Futures CRC.
Summer dormant tall fescue is starting to be used instead of perennial ryegrass in drier areas, as well as in place of phalaris in acid soils.