Water Lettuce

Water lettuce Pistia stratiottes This is a water plant to be on the alert for in South Gippsland. Local landholders often have there dams invaded by various water weeds causing major problems with water quality and choked pipes and troughs. This plant not common as yet in this district has the potential with our changing climate, warming of farm dams and lack of frosts is set to become a serious weed. It declared noxious in the states to the north and west but not yet in Victoria. It is a free floating perennial aquatic herb, which consists of a dense rosette of overlapping leaves on a short stem with long feathery roots, reproducing vegetatively and by seed. The seeds float and can spread through waterways, and the main colony will also spread by the development of daughter plants. Water lettuce is commonly sold in nurseries and through the aquarium trade. Once established it will spread quickly take over the entire surface of freshwater lakes and dams, rivers and canals. The dense plant mass will reduce light penetration, oxygen concentration and pH levels in the water, thus destroying the habitat of fish and is a good shelter for mosquitoes. Control is difficult mainly by manual of mechanical removal. Chemical control is possible but not desirable.

Inkweed

Ink-weed Phytolacca octandra This erect, herbaceous perennial from tropical America used to be a noxious weed in Victoria. It is still considered to be a troublesome weed. It infests bare soil areas and is spread by birds colonising large areas Ink-weed can grow up to 2 metres high and has brittle spreading branches. Red coloured stems which grow from a well developed tap root. It has smooth bright green leaves. Greenish white flowers occur close together on upright tapered spikes between August and November. The fruit are dark purple to black berries which exude a red-purple juice. This plant can turn up in gardens and bushland unnoticed and can dominate large areas inhibiting the growth of more desirable species. Ink-weed can be grubbed out being careful to get as much of the tap root as possible. It will also respond well to being sprayed with an appropriate herbicide. Brush Off can be effective.