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Knot on the North Island

RDMW is planning to manage the growing Knotweed infestation on the North Island

Starting this summer, the Regional District of Mount Waddington (RDMW) is planning to manage the increasing Knotweed infestation within the North Island area.  Japanese, Giant, Bohemian and Himalayan Knotweed are all alien invasive plants that aggressively displace native vegetation species and disrupt ecosystem functions.

They are listed by the World Conservation Union as some of the worst invasive species.

The aggressive root system and rapidly growing shoots can damage concrete foundations, water/sewer mains and transportation infrastructure in addition to causing serious environmental harm.

In Great Britain, you can’t get a mortgage on a property that has knotweed as the banks deem it too risky and this may eventually happen here.   As a home owner, think what it would cost you if you can’t sell your home to anyone who needs to borrow money from the bank?

Knotweed establishes easily along streams, roadsides and often where garden waste is discarded. It forms thick, dense colonies that completely crowds out all other plants. Its root systems can extend seven metres away from the plant and penetrate three  metres into the ground, making removal by excavation extremely difficult.

The most effective control for knotweed is through the use of herbicides which are normally injected directly into the stem. Trying to dig it out or cut it down usually just spreads it further.  One of the biggest contributors to its spreading are people who mow it down inadvertently.

All the bits pieces can be the start of new plants.  Because this plant is so aggressive and persistent, it may take many years of monitoring and repeated treatments to eradicate this pest.

The best way to halt the spread of knotweed and other aggressive invasive plant species is to responsibly dispose of vegetation matter from our gardens.  Vegetative waste material is some of the most troublesome encountered as it frequently takes roots and begins to grow and spread out.  For all intents it is an infection on the landscape not unlike the flu or measles.

7 Mile Landfill accepts grass, cuttings and other plant waste up to a two inch diameter for free.  Larger wood waste is charged a much lower tipping fee than regular garbage.  All this organic waste is composted so as not fill up the landfill with the exception of knotweed.  It is so aggressive that all we can do is bury it.

Additionally, the RDMW is seeking your help to identify Knotweed infested sites within the North Island. Please direct all inquiries regarding Knotweed management to knotweed@rdmw.bc.ca .  For further information about Knotweed, its biology, and control methods, please visit http://www.coastalisc.com and http://knotonmyproperty.com

 



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