Shropshire Botanical Society Newsletter - Autumn 2000 - page 7
Brown Moss continues to provide a challenge. The removal of many of the trees does indeed seem to have been a great improvement, with water levels staying high, the shaded-out vegetation recovering, and some - but not all - of the "lost" species returning. However, a lot more trees need to come down, and ideally grazing should be reintroduced. The New Zealand Pigmyweed, Crassula helmsii, has completely defeated the efforts to eradicate it, and now Water Fern, Azolla filiculoides, has become established. I am worried about the apparent disappearance of Shoreweed, Littorella uniflora, and Small-fruited Yellow-sedge, Carex viridula ssp. viridula - the latter at its only site in Shropshire.
The Montgomery Canal was very fine this year, as boats were virtually excluded from the newly-restored sections below Queens Head. This allowed the vegetation to flourish, and both Grass-wrack and Flat-stalked Pondweeds, Potamogeton compressus & P. friesii, were both seen - the latter in huge quantities. However, a farm pollution incident in the Rednal area led to a massive bloom of algae and duckweeds, that cut out much light from the depths, and reversed some of these gains. One of the great advantages of the Welsh lengths of the canal is that there is a healthy through-flow of clean water, which reduces the deposition of silt and can flush out such pollution.
The Golden Ragwort Award this time goes to Shropshire Hills Countryside Unit, for arguably inappropriate conservation advice. I have now come across two situations where the Unit has given advice leading to damage of good quality grasslands in the name of conservation. In the first instance a proportion of a magnificent hay meadow - a unique site in Shropshire, with abundant Broad-leaved Helleborine, Epipactis helleborine - was planted up with trees to create a much less valuable secondary woodland. And this summer I visited another MG5 grassland site, where the owners had been advised to dig a pond in a somewhat inappropriate spot. An area within a good grassland sward had been turned into a water body of relatively little ecological significance. This is one of the dangers of habitat creation and restoration - there are only environmental benefits when degraded habitats are replaced with potentially better ones - I guess that this is yet another discipline where a little knowledge is a dangerous thing.