Loch Lomond NNR
Stephen Longster, Reserves Officer writes about why Invasive Non-Native plant species (INNS) can be a problem at Loch Lomond and which of our valuable native species, often the tiny ones, can suffer as a result:
Loch Lomond NNR has one of the best rare plant assemblages or any wetland anywhere in the country. Nine rare plant species make up the total. Four of these are aquatic or semi-aquatic and these can be vulnerable to swamping by INNS which also have found a home on the reserve. The plants that can be at risk are generally tiny, barely noticeable, are often under water.
A couple of examples are:
Needle Spike Rush – an underwater specialist that grows to the height of 5-10cms.
Narrow leaved Water Star-wort – you can tell what a giant this one is, by the grains of sand stuck to it.
Both of these species need open muddy ground and, or, shallow water to flourish, which makes them especially at risk from plants like Elodea Canadensis, Canadian Waterweed which was originally sold as an oxygenator for ornamental ponds.
This plant is great for its uptake of CO, which you might think would be a good thing; CO₂being one of the less popular gases at moment. However it uses so much CO₂, it can deprive other plants of this gas which is essential to growth. It also blooms and shades out the smaller plants.
Not all the native plants that make up the rare plant assemblage are titchy.
One of the plants potentially at risk from the march of the INNS is Elongated Sedge which has the Latin name Carex elongate; just to make life easy.
This beautiful bright green sedge grows along the wet margins of ditches; precisely the sort of place one of the most aggressive of the INNS species, Himalayan Balsam likes to live.