Primslips or Cowroses?

The wild flower conservation charity Plantlife is conducting a poll to find Britain's favourite wild flower and the primrose Primula vulgaris is a strong contender to take the title. Currently it is in top position in Scotland and Wales, second in England and third in Northern Ireland.

Primrose is primarily a plant of woodland edges, glades and hedgebanks, growing best in dappled shade and in moist soils. It's also a very variable plant, thanks to its breeding system, where there are two forms of flower - pin-eyed and thrum-eyed - with the stamens and stigma arranged in a way that ensures cross pollination when insects travel from plant to plant. 

Pin-eyed flowers have their stigma at the top of the floral tube and their stamens lower down, whereas ...

... thrum-eyed flowers have stamens at the top, with the stigma hidden underneath them.  It's an arrangement that maximises the chances of cross-pollination, reinfornced with an incompatibility system where the flower's own pollen will not normally germinate on its own stigma. The cross-pollination that this enforces generates genetic variability within the population - compare the broad-petalled flower above with ....

.. this one which has much narrower petals.

Primrose also readily crosses with .....

....... cowslip Primula veris wherever the two species meet, typically where woodlands meet the pastures that are the favoured habitats of cowslips. 

Populations of false oxlips, the natural hybrid between the two species, show almost every grade of intermediate form between pure cowslip and pure primrose..... with what you might call primslips and cowroses in between!

Cowslips typically have these small, intense yellow, downward-pointing flowers whereas .... 

..... false oxlip flowers tend to point outwards or even upwards and are larger and paler coloured. The false oxlip - with an injection of genes from a cross with at least one other more colourful European species ....

....... is the ancestor of the gaudy, very popular polyanthus that is the mainstay of so many municipal bedding schemes in spring.

Newly minted butterfly.....

We found this newly-emerged green-veined white, still 'pumping up' its hind wings, when we walked along the sea cliffs south of Seaham this morning.

This early purple orchid - the first I've seen this year - was flowering in the meadows near Hawthorn Dene and was already past its best. Spring flowers are enjoying a very short season this year, having been held back for so long............... 

........... but the display of cowslips in the same meadow is magnificent. We also saw ....

............ a few false oxlips, which are the natural hybrid between primroses and cowslips.

Down on Blast beach, at the base of the cliffs, landslips have created sheltered, steep banks at the top of the beach that are carpeted in primroses.




The finest floral display, though, is at the top of the cliffs, where the gorse is in full bloom, with its wonderful coconut aroma and .....




...flowers that are so closely packed together that they completely hide the bushes

Primslips and Cowroses

The old railway line between Romaldkirk and Cotherstone in Teesdale is now a very attractive public footpath (with a convenient pub at either end) and this year there are spectacular displays of ....

...primroses Primula vulgaris in the woodland that has developed on the embankments and ....

... cowslips Primula veris  in the grass in the pastures and more open areas, and wherever these two habitats coincide there are ....

...... magnificent specimens of false oxlips, the natural hybrid between the two species. Every wild flower guide describes primroses and cowslips as separate, distinct species but no one told the plants, or the insects that cross pollinate them in spring. The hybrids tend to have the large individual flowers of primroses mounted on the tall stems of cowslips and are often very floriferous, displaying hybrid vigour. False oxlips have been grown in gardens since at least Elizabethan times and are the ancestors of the garden polyanthus, that has also received an injection of floral pigment genes from another European primrose species at some point in its history. Almost every false oxlip plant is subtly distinct because they can also backcross to either parent, so every conceivable intermediate form is there in the population. Along this railway line enbankment there's also just one ....

..... pink-flowered primrose, that must be the result of a cross with a cultivated Primula species. The bumblebee - slightly to the right and above centre in the picture - was busy disseminating this coloured variant's genes amongst the surronding plants in the population.