Soft Rush (Juncus effusus) and Hard Rush (Juncus inflexus) are perennial rushes that grow in damp grassland, marshes and ditches and so can be found near Whightknights Lake. Unlike J. inflexus, J. effusus avoids base rich soils but can grow in acidic conditions (Clapham et al., 1952 & Preston et al. 2002).
Juncus effusus (C) Christian Fischer
Juncus inflexus (C) Kristian Peters -- Fabelfroh
Other differences between the two species include a deeply furrowed, glaucous stem and interrupted pith in J. inflexus, while J. effusus has a bright green, unridged and much softer stem with uninterrupted pith (Stace 2010). J. effusus is a common plant throughout Great Britain and can be persistent, as animals dislike eating the stiff stems and its presence suppresses the development of fodder grasses (Christianson, 1979). J. inflexus is equally common in England and Wales but rarely grows in Scotland (Sterry, 2006).
The inflorescences in both species are both fairly lax, J. inflexus having a quite distinctive form, in that the flowers are borne on erect stalks of unequal length (Fletcher 2008). Both species usually flower between June and August and can hybridise (Juncus x diffusus). This hybrid is not glaucous and has continuous pith (Stace 2010). In the past, the pith in both species was used as candle wicks whilst the tougher stems were crafted into baskets (Christiansen, 1979).
Images: http://da.wikipedia.org/wiki/Fil:JuncusEffusus.jpg; http://en.wikipedia.org/wiki/File:Juncus_inflexus.jpeg
References:
Christiansen, M. (1977) Grasses, Sedges and Rushes in Colour. Blandford Press Ltd. Poole, Dorset.
Clapham, A.R., Tutin T.G. and Warburg, E.F. (1952) Flora of the British Isles. Cambridge University Press, Cambridge.
Fletcher, N. (2008) Wildlife of Britain. Dorling Kindersley Ltd. London.
Preston, C. D., Pearman, D.A. and Dimes, T.D. (2002) New Atlas of the British Flora. Oxford University Press. Oxford.
Stace, C. (2010) New Flora of the British Isles, 3rd Edition. Cambridge University Press, Cambridge.
Sterry, P. (2006) Complete British Wild Flowers. Collins Publishing. London.
I’m pleased to see a blog on a group that is often neglected. The Rushes are remarkably frequent in damp areas but some can be confusing to tell apart.