EverGraze Action – Growing and using winter active tall fescue in southern Australia
Tall fescue is a perennial temperate grass that is closely related to perennial ryegrass, but which does not cause ryegrass staggers.
There is a wide range of tall fescue cultivars available which vary from being highly winter-active to highly summer-active. It is important to specify which type of fescue you want when requesting information or purchasing seed.
In the field, it is difficult to tell the difference between winter- and summer-active cultivars of tall fescue.
Both have dark green leaf blades that typically grow up to 30 cm long. The upper surface of the leaf is dull with distinct veins that run the length of the leaf blade. The purple/green seed heads are loosely bunched.
Both types of tall fescue are more deep rooted than perennial ryegrass or cocksfoot and can have roots to a depth of 2 m.
Summer-active tall fescue is better able to extract moisture from deep in the soil profile than winter-active tall fescue due to its higher density of roots at depth.
This enables summer-active tall fescue to use stored soil moisture for growth during dry conditions when the winter-active cultivars become dormant.
This dormancy mechanism makes winter-active tall fescue more persistent than summer-active tall fescue in dry conditions where rainfall is winter dominant or where light sandy loam soils don’t retain moisture.
For instance, winter-active tall fescue swards at Hamilton in Victoria have retained a plant frequency of 75% four years after sowing (plants were present in 75 out of 100 random quadrats), where summer-active tall fescue only retained a plant frequency of 60%.
Winter-active tall fescue has also proven to be more persistent than summer-active cultivars at Wellstead in southern WA, where rainfall is less than 600 mm/annum and soils have a sandy texture.
Winter-active tall fescue survives hot and dry conditions by minimising its green leaf area, which reduces its water use and makes it less susceptible to scorching.