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General News · 5th October 2016
Christine Robinson
An invasive species of knotweed has been identified by the Whaletown Creek, and will be investigated by the Cortes Streamkeepers, FOCI, and the regional district.

It is of the utmost importance that the area with the knotweed not be disturbed in anyway, until there is professional support & advice on the best approach to eradication. Knotweed can be easily spread with the best of intentions and the wrong approach. The attached photo shows the flowering phase which is just finishing.

Please contact Cortes Streamkeepers (Cec, Christine Robinson -6428) if anyone suspects they know of another location on Cortes with knotweed.

The following is a summary of knotweed species taken from the BC ‘Invasive Species Committee’ website, but for further specific information, please read more at: http://www.coastalisc.com

"Invasive Knotweeds: Japanese, Giant, Bohemian & Himalayan (Fallopia japonica, Fallopia sachalinensis, Fallopia x bohemica & Polygonum polystachum)
Knotweed Species are found throughout communities on Vancouver Island, the Gulf Islands and the Sunshine Coast.
These non-native, invasive species are listed by the World Conservation Union as one of the world's worst invasive species.
The invasive root system and strong growth can damage concrete foundations, buildings, septic systems, roads, paving, retaining walls and the environment.
Knotweed can easily take hold in riparian ecosystems, roadsides and waste places. It forms thick, dense colonies that completely crowd out all other plants. The success of the species has been partially attributed to its tolerance of a very wide range of soil types, pH and salinity. Its rhizomes can extend 7 metres (23 ft) horizontally and 3 metres (9.8 ft) deep, making removal by excavation extremely difficult. Additionally even tiny root fragments can regrow into new plants.The plant is also resilient to cutting, vigorously resprouting from the roots."
Interesting article
Comment by Bertha Jeffery on 10th October 2016
Here is an interesting article from McLeans.
http://www.macleans.ca/society/science/the-plant-thats-eating-b-c/
To clarify, the plants at Co-op are Pokeweed
Comment by myann on 6th October 2016
...genus phytolacca, also known as pokeroot. These are grown as ornamentals in our climate and do not appear to be invasive.
Knotweed
Comment by okellhammer on 6th October 2016
This has been here near the S-bend for some years and I haven't yet seen any signs of it spreading. Knotweed seems to like disturbance so it would be a good idea to continue monitoring roadsides and clearcuts to track its progress. Ditching work might spread pieces or rhizomes. This plant is very common in urban areas.

As with most exotics, there are many downsides but some upsides. Let's not be tempted to go the Round Up route as this is now regarded as a carcinogen as well as a biocide affecting aquatic life. From Wikipedia: Japanese knotweed flowers are valued by some beekeepers as an important source of nectar for honeybees, at a time of year when little else is flowering. Japanese knotweed yields a monofloral honey, usually called bamboo honey by northeastern U.S. beekeepers, like a mild-flavored version of buckwheat honey (a related plant also in the Polygonaceae).

The young stems are edible as a spring vegetable, with a flavor similar to extremely sour rhubarb. In some locations, semi-cultivating Japanese knotweed for food has been used as a means of controlling knotweed populations that invade sensitive wetland areas and drive out the native vegetation.[22] It is eaten in Japan as sansai or wild foraged vegetable.