The Gentian Family
What are they?
Although the gentian family (Gentianaceae) is quite variable, members can generally be recognised by their smooth appearance, opposite leaves and usually terminal, vividly-coloured flowers. Most members of the family seem always to have been scarce in the region and their presence at a location is often taken as a sign of a well-preserved habitat. Most species have four or five petals (one has eight) with the petals fused into a tube towards the base.
Where are they found?
Most species occur in good quality, grassy habitats on both chalky and acid soils, including heaths, commons and coastal areas such as dunes and cliff tops.
Identification
Most species are relatively easy to identify using the details given below. The exception comes with the centauries, where very careful attention needs to be paid to flower structure and bract placement, as well as leaf shape.
Common Centaury Centaurium erythraea
Native. Found in areas of short or close-cropped grass, including coastal cliffs and dunes. Flowers June to October. Very similar to Lesser Centaury and hard to tell from it. Best key characters include the presence of a basal rosette of leaves and a gap of 1mm or less between the base of the sepals and the topmost bracts.
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Lesser Centaury Centaurium puchellum
Native. Has probably always been rare in East Anglia and some records may well be due to confusion with Common Centaury. Scattered in areas of short grass, especially near the coast. Flowers June to October. Very similar to Common Centaury and hard to tell from it. Best key characters include the absence of a basal rosette of leaves and a gap of 1m-4mm between the base of the sepals and the topmost bracts.
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Yellow-wort Blackstonia perfoliata
Native. Rare in East Anglia due to an absence of suitable habitat, but found at scattered locations on chalky soils in more southerly and westerly parts of the region. Flowers June to October. The brilliant yellow, eight-petalled flowers and glaucous, perfoliate leaves are unique.
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Autumn Gentian Gentianella amarella
Native. A plant of well-cropped, grassy places on thin chalk soils, alomst absent from the east of the region but more frequent in the west. Flowers August to Septemer. The flowers are variable and may have four or five petal lobes.
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Field Gentian Gentianella campestris
Native. Of uncertain status in East Anglia and possibly recently extinct, but worth keeping an eye out for. Formerly a scarce plant of grassy places. Flowers July to October. Differs from the rather similar Autumn Gentian by the calyx lobes, two of which are much larger than the other two, while the flowers always have four petals.
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Marsh Gentian Gentiana pneumonanthe
Native. Very rare in damp heathland; now extint in Suffolk and confined to just four locations in Norfolk. Flowers August to September. Unique in our region with narrow, linear leaves and rich blue trumpet-shaped flowers carried one to five on a stem.
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