Finnoo bird basin as a seed bank
The bird basin in Suomenoja has an outlet pipe, in order to prevent overflow. In March 2013 the pipe was blocked and dredging operations were needed. Unfortunately the sludge disposal place was one of the best butterfly meadows in Suomenoja. Suomenojan Luonto tried to compensate the damages by planting flowers, which collect butterflies - i.e. making "a butterfly bar". The summer 2013 was dry and hot so nothing popped up. Instead some specialites and rare species appeared like Creeping Toadflax. Obviously they came with the sludge. The summer 2014 started in a similar way: just nothing popped up in the butterfly bar and typical wasteland plants appeared around it. But in July a peculiar plant was found in the disposal area. First it was thought to be somekind relative to Giant Globe Thistle or Eryngium-species. Later a couple of flora specialists recognized it as Wild Teasel, which has been found in Finland earlier only once (2010). It is clear it has come with the sludge. It is interesting that it is a real attraction to butterflies and bees. Most likely the birds have "imported" it to Finland and to the basin. The basin bottom or sludge has acted as a "seed bank".
Wild Teasel pictures:
Sludge disposal and dredging:
