Speaker was Keith McDougall. Friday 27 January 2006.

A diverse area. Kosciuszko Plateau is a floristically diverse area. It has 900 vascular plant species, which is 26% of the NSW flora in only 1% of the state's area. 45% of the plants are in treeless vegetation and are largely restricted to that area. 200 native plants are specific to Kosciuszko and 40 alpine species are endemic. Grasses, daisies and sedges dominate with 30% of the flora.

Diversity can be influenced by:

• The steep altitudinal gradient from 300 metres in the valleys to 2229 metres at Mt Kosciuszko.
• The large rainfall gradient from Suggan Buggan to Charlottte Pass.

Vegetation zones. At low elevation (less than 888m) in the Snowy River Gorge there is open woodland with Black Cypress-pine and White Box. The montane forest from 800-1400m is dominated by gums and Alpine Ash. The sub-alpine zone from 1400-1700m has Snow Gum with grass and shrubs. Some valleys however are treeless because the temperature can drop to –20^oC. The biodiversity of sub-alpine treeless plains is under-estimated. Eucalyptus lacrimans is a droopy tree and lies down on the ground under snow. There are 20 endemic plants in the treeless zone. Many of these plants are threatened because pigs root in the grassland areas.

The alpine zone has a large range of plant communities and has remarkable similarities to alpine communities in other parts of the world. Alpine plants have adaptations to the environment:

• Plants growing points are close to the ground.
• Transpiration rates are low to survive on the scarce water.
• Growth rates are low.
• Shrubs have springy stems which grow down slope. They lie on the ground when covered with snow and spring back after the melt.
• Pre-formed flower buds allow early flowering and quick reproduction after snowmelt.
• Root systems of seedlings develop quickly giving good anchorage to survive needle ice formation which lifts soil. Needle ice forms perpendicular to the surface, lifts the soil and as it melts the soil moves down the slope.
• The flower colours are mainly white or yellow, to attract moths that are the main pollinator.

Feldmark is a special community in Kosciuszko National Park. They occur in windswept areas where snow does not form a protective insulating blanket over the vegetation.

Threatening processes to alpine communities include:

• Introduced plants, particularly those which spread from gardens.
• Spagnum moss is a fast grower (4-10cm per year) and in capable of encroaching on alpine herb fields.
• People create considerable disturbance, particularly in areas used for skiing.
• Sheep and cattle grazing are now phased out but trampling severely damaged bogs.
• At Mt Twynam native moths have killed patches of grass.
• Major fires occurred in 2003 and 1939. Response to fires differs between communities.

Climate change. Woody plants areas are increasing. Snow patch vegetation and feldmarks will lose out.

Pam Faragher.

1: Alpine Colobanth - a feldmark species.
2: Snow Gum, at the edge of the treeline. Perisher, 1994.>