Sedges have edges.....

Ecologist Lindsay Stronge recently attended a training course on sedge identification with the Species Recovery Trust.

Bulbous Rush

Graminoids (plants such as sedges, rushes and grasses) are found in a wide variety of habitats including woodland, grassland and wetlands. Identification of graminoids can be off-putting for many people, as at a first glance many species appear similar. Their inflorescences (flowers) are often much reduced and described using different terminology to plants from other families. Identification of sedges and their allies is an important skill for ecologists conducting habitat surveys.  Many species are ancient woodland indicators e.g. Wood club rush (Scirpus sylvaticus) or Remote sedge (Carex remota) whilst the presence of others may provide clues to underlying habitat conditions e.g. Pill sedge (Carex pilulifera) is usually characteristic of acidic land whilst Great Fen-sedge (Cladium mariscus) often indicates calcareous fen.

This one day course led by expert botanist Dr Phil Wilson provided an introduction to twenty-five sedges, nine rushes and a handful of cotton-grasses, woodrushes, spike rush and deer grass. The setting for the course was Hartland Moor, a c. 300ha SSSI in Dorset which holds one of the largest areas of lowland heath and mire in the UK. The valley mire was so species rich that we barely strayed 100m from the road; many of our target species were located within a few steps. This corner of Dorset has a varied geology and hydrology resulting in some parts of the moor being acidic whilst others are base rich. The resulting mosaic of habitats and plant communities is fascinating.

Carex panicea with 'chocolate lime' fruits

Phil provided an informative and accessible introduction to the plants as we got to grips with utricles (the structure that surrounds the sedge fruit) and bracts (much reduced leaf-like structures). We looked at inflorescences and distinguishing vegetative characteristics. It will be easy to remember the ‘rioja wine’ colour of old Common cotton-grass (Eriophorum angustifolium) leaves and the ‘chocolate lime’ fruits of Carnation sedge (Carex panicea) in future. I left the course better equipped to tackle the sedges I encounter in day to day surveys and with a new appreciation for the variety of species present in the UK.