Salix cinerea (Pussy Willow, Common Sallow)

This plant is a weed of National Significance. Grey sallow is the only willow species known to invade non-riparian habitats. Provided there is sufficient soil moisture available, grey sallow can rapidly form dense stands in a variety of environments. It has invaded riverine and wetland habitat through to pristine alpine regions. Grey sallow can remain relatively stable in size for a long period of time, and then experience a population explosion under the right conditions.

Grey sallow affects riverine health and stream bank stability. It does this by; crowding out native species, spreading its large root network into the water, taking up large amounts of water and eventually diverting the natural flow of water.  The annual autumn leaf-drop can also affect water quality by suddenly increasing organic matter and nutrient levels.

DPI WeedWise Grey Sallow

http://keyserver.lucidcentral.org/weeds/data/media/Html/salix_cinerea.htm

http://www.environment.gov.au/cgi-bin/biodiversity/invasive/weeds/weeddetails.pl?taxon_id=68497