Sedge Group 6
What are they?
This group includes sedge species that have their flowers arranged in several spikelets, with the upper spikelets made up of all (or mostly all) male and the lower spikelets made up of all female flowers. There is thus a clear different between the upper and lower spikelets. The hairless utricles in members of this group separates them from Group 3 sedges, while the female flowers with three stigmas separates them from group 4 sedges. As with the sedge species in group 5, the flower spikelets become clearly pendulous as the fruits develop, but in this group, the plants themselves do not form tight tussocks of leaves.
Where are they found?
These are sedges of wetland habitats, typically found along the margins of permanently wet areas such as larger rivers, ponds and lakes.
Identification
While the overall flower spike details define this group, the finer details of the flowers and fruits are necessary for species identification. Note the shape and colour of both the male and female glumes (flower bracts) and note details of shape and size of the ripe utricles (fruits).
Lesser Pond Sedge Carex acutiformis
Native. Widespread and common along rivers, larger ditches and channels and beside ponds, lakes and broads. Will often grow in shady conditions in alder and willow carr and other wet woods. Flowers June to July, fruits July to September. Plants form extensive spreading colonies (sedge beds), 60-150cm in height. Leaves 7-10mm wide, with a pointed ligule. Flower spike about one third the length of the stem, with 2-3 male and 3-4 female spikelets. male glumes obtuse to subacute at the tip; female glumes acute. Flowers usually with three stigmas but occasionally with two. Utricles 3.5-5mm long, elliptical to oval, flattened, with beak 0.5mm long and slightly notched at the tip.
Often grows together with Greater Pond Sedge, from which it is most easily told by the shape of the tips of the glumes (if in flower) or by the shape of the leaf ligule.
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Greater Pond Sedge Carex riparia
Native. Widespread and common along rivers, larger ditches and channels and beside ponds, lakes and broads. Will often grow in shady conditions in alder and willow carr and other wet woods. Flowers May to June, fruits June to September. Plants form extensive spreading colonies (sedge beds), 60-130cm in height. Leaves 6-15mm wide, with a rounded ligule. Flower spike about one third the length of the stem, with 3-6 male and 1-5 female spikelets. male and female glumes with long acuminate tips. Flowers with three stigmas. Utricles 5-8mm long, oval, slightly inflated, with beak 1-2mm long and clearly notched at the tip.
Often grows together with Lesser Pond Sedge, from which it is most easily told by the shape of the tips of the glumes (if in flower) or by the shape of the leaf ligule.
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Glaucous Sedge Carex flacca
Native. Common and widespread in places with relatively short grass and in chalky fens. Unusually, this is a sedge that will grow in both wet and very dry soils. Flowers May to June, fruits June to September. Plants form spreading colonies of tufted shoots, 10-60cm in height. Leaves 1.5-4mm wide, dull green above, pale blue-green below with the midrib groove running all the way to the tip of the leaf. Flower spike 2-3cm long with (1)2-3 male and 1-5 female spikelets. Flowers with three stigmas. Utricles small, 2-3mm long, ellipsoid to obovoid, minutely warty with a minuscule beak, 0.2-0.3mm long.
Often grows with the somewhat similar Carnation Sedge, but that species has leaves with a midrib groove that stops well short of the leaf tip.
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stigmas mature |
stigmas mature |
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Carex x justi-schmidtii
Native. A very rare hybrid that has been recorded just three times in Britain, but one of those records comes from West Norfolk and the individual photographed here was also located in West Norfolk in 2020, so it is certainly worth looking out for. The hybrid shows mixed features between the two parents, Cyperus Sedge and Bottle Sedge. Identification features shown in the photographs include: Female spikes stalked and becoming slightly pendulous as fruits develop; Female glumes as long as utricles and with acute, elongate tips; utricules intermediate in shape between the two parents; utricles hollow as the plants are infertile and don't form seeds; leaves glaucous on underside.
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| for comparison |
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