Silver tussock Poa cita
Diagnostic features for identification in the field
A dense shiny fawn green (dead leaves are mixed in with fresh green ones) tussock -30 to 70cm tall
Leaves tightly folded, leathery, smooth above, fringed with hairs along the margins below; tip sharp.
Leaf sheath creamy brown, shiny, with rough margin.
Ligule is leathery, very short and even.
Flower heads (30-100cm) do not stand proud of leaves. Panicle is open, slender, rough, with twisted branches. Awns absent.
References:
Jane, G. 1995. Field Guide to Grasses. A. Alpine Grasses
Wilson, H.J. 1996: Wild plants of Mount Cook National Park, Manuka Press, Christchurch
Description of community and habitat Silver tussocks are found from the coast in central and southern new Zealand, to the penalpine zone. Although widespread in a range of grassland and shrubland communities, it seldom dominate the vegetation.
Silver tussocks prefer a high fertility environment. They are therefore associated with three classes of habitat:
Silver tussocks were presumably present in this mixed shrubland-grassland community, and was able to migrate upslope during the period of deforestation. At the same time, tall tussock species were migrating downslope from their alpine environments, replacing the short tussock grasslands.
Since European settlement, these tall tussock grasslands have been repeatedly burnt and grazed, often with the aim to reduce the cover of the tall tussocks in favour of the more palatable short tussock species. More recently, many of these short tussock grasslands have been the focus of pastoral development programmes, which has increased the soil fertility and introduced exotic pastoral species. Where present, silver tussocks have responded well to the boost in soil fertility, and can become the dominant tussock present, as other native species fail to compete with the more vigorous exotic species.
This information was taken from Wardle, P.; 1991. Vegetation of New Zealand, Cambridge Press, Cambridge.
Leaves tightly folded, leathery, smooth above, fringed with hairs along the margins below; tip sharp.
Leaf sheath creamy brown, shiny, with rough margin.
Ligule is leathery, very short and even.
Flower heads (30-100cm) do not stand proud of leaves. Panicle is open, slender, rough, with twisted branches. Awns absent.
References:
Jane, G. 1995. Field Guide to Grasses. A. Alpine Grasses
Wilson, H.J. 1996: Wild plants of Mount Cook National Park, Manuka Press, Christchurch
Description of community and habitat Silver tussocks are found from the coast in central and southern new Zealand, to the penalpine zone. Although widespread in a range of grassland and shrubland communities, it seldom dominate the vegetation.
Silver tussocks prefer a high fertility environment. They are therefore associated with three classes of habitat:
Silver tussocks were presumably present in this mixed shrubland-grassland community, and was able to migrate upslope during the period of deforestation. At the same time, tall tussock species were migrating downslope from their alpine environments, replacing the short tussock grasslands.
Since European settlement, these tall tussock grasslands have been repeatedly burnt and grazed, often with the aim to reduce the cover of the tall tussocks in favour of the more palatable short tussock species. More recently, many of these short tussock grasslands have been the focus of pastoral development programmes, which has increased the soil fertility and introduced exotic pastoral species. Where present, silver tussocks have responded well to the boost in soil fertility, and can become the dominant tussock present, as other native species fail to compete with the more vigorous exotic species.
This information was taken from Wardle, P.; 1991. Vegetation of New Zealand, Cambridge Press, Cambridge.
Many areas which once supported dryland short tussock grasslands have been the focus of large-scale irrigation schemes. Such areas have been transformed to improved pasture and orchards.
Few areas of dryland short tussock grassland are in existence today.
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