landgirl's picture


Around my location, both Centaurium erythaea and C. pulchellum are frequently found. Sometimes I find it really difficult to tell which I am looking at. What do people think are the most reliable features? I've been using presence or absence of basal rosette, then size, colour and shape of petals - not having much success with the flower being stalked or not. I've also always thought that C. pulchellum prefers damper conditions, but at least one book (Streeter) says dry. Stace gives areas where hybrids have been found, which doesn't include East Northamptonshire, but isn't it likely that some might be found here?



martinjohnbishop's picture

The hybrid is not listed in

The new edition of The Flora of Northamptonshire and the Soke of Peterborough has been published recently (2013). This edition is a complete re-survey of the county with up-to-date picture of plant distribution, making a unique recording of more than 1800 species.
Might be worth having a look at that.


landgirl's picture

Thanks Martin

I was a contributor to that! But just because we didn't record it, doesn't mean it's not there...

anonymous spotter's picture

they are instantly

they are instantly distinguished on flower size - measure the total length of the petlas from base to tip of petals = 4-8 mm = pulchellum, 10-20 = erythraea. I find other characters hard as well.
If you are not sure what it is, then it is probably erthraea
pulchellum grows on wide range from damp woodland rides and dune slacks to dry chalk grassland and quarry spoil

landgirl's picture


But so many seem to be intermediate in size, and C. erythraea can be very dwarfed. Most of the habitats where Centaurium grows round here are sites of old quarries.

John Bratton's picture

If there are plenty of them,

If there are plenty of them, you could send a couple to Tim Rich at the museum in Cardiff. I think he is working on a BSBI handbook to the family.

On the Anglesey dunes the flowers of pulchellum are noticably darker, but that probably isn't any help in recognising the hybrid.