Weeds are often excellent at surviving and reproducing in disturbed environments and are commonly the first species to colonise and dominate in these conditions, typically producing large numbers of seeds, thus assisting their spread.
Sheep sorrel (Rumex acetosella) above is a major weed worldwide. Weeds pose a serious threat to human and animal health, to primary production and to our natural environment by reducing farm productivity, displacing native species and contributing to on-going land degradation and reducing land values. It is estimated that weed control measures cost Australian farmers $1.5 billion dollars per year and that weeds cost $2.5 billion dollars per year in lost agricultural production.
While many plants introduced into Australia in the last 200 years have become weeds, a native species that colonises and persists in an ecosystem in which it did not previously exist can also be a weed.[/vc_column_text][/vc_column][/vc_row]