The Bells! The Bells!

The largest and smallest species of Campanula in County Durham are flowering in Weardale now.

This is the giant bellflower Campanula latifolia, which graces old hedgerows and woodland edges, and .....

..... this is harebell Campanula rotundifolia, which is often seen at its best in short, dry grassland where its slender stems tremble in the slightest breeze.

It’s worth taking a close look at harebell flowers because they have a really neat fail-safe method of ensuring that they’re pollinated.

When the flower is still in bud the style, with a closed stigma at its tip, is surrounded by five stamens that begin to shed pollen. As the style - which is hairy on the outside- elongates inside the bud it forces its way through the tube of stamens surrounding it, sweeping the pollen from their surface. So when the flower opens it looks like this, and any insect forcing its way down to the bottom of the harebell bell will pick up pollen from the outside of the style. At this stage the flower is functionally male, dispensing pollen.

 Once the pollen is all gone the tip of the style splits into three lobes that curl back and now the flower has effectively become female, ready to receive pollen on one of those three stigma lobes from a visiting insect. But what if no pollen-laden insects turn up? No problem; those stigma lobes just keep curling back until they pick up any residual pollen that’s still left on the outside of the style, so the flower self-pollinates. 

Harebells are quite easy to grow from seed and if you do raise some you’ll see why their Latin name is Campanula rotundifolia, even though the plant has long, grass-like leaves: the leaves in the seedling rosette are indeed rotund.

...... and now for the good news.....

If you let it, taking an interest in natural history could be very depressing because so much that is written about our flora and fauna in the press seems to be unrelenting bad news. The abysmal weather in the early part of this summer  produced also sorts of hyperbolic headlines of the disastrous/cataclysmic/catastrophic kind about its likely impact on birds/butterflies/insects and almost everything else in the natural world - and it's undoubtedly true that it has been a bad summer for all of these (although it's important to bear in mind that over last few thousand years there have been periods of far more adverse climatic conditions that our wildlife experienced and rebounded from: like investments, rates of growth in populations of living organisms can go down as well as up, all the time). The natural world isn't a natural history museum, it's a living, constantly evolving interplay between organisms.

Anyway, last weekend we happened to notice a positive effect of the wet early part of the summer, when we took a walk along the cliff tops between Dawdon and Hawthorn Dene on the Durham Coast Heritage Path. The summer wild flowers there seem to be flowering more spectacularly than I can ever remember. I have a theory as to why this might be so, and it's all down to the rain. 

The cliffs are porous magnesian limestone which is free-draining. In a 'normal' summer the surface soil dries out quickly and the plants suffer from moisture stress, so they flower quickly while they have the chance, when they are quite small. This year, with plenty of water, the well-watered vegetation is unusually lush and as a result the flowers are truly spectacular. So, without further ado, here are some examples....

Drifts of meadowsweet in the gullies on the cliffs and ....

.... forming a backdrop for devil's bit scabious which .....

...... includes some exceptionally fine examples ..... although this one looks a tad unusual - very short bracts under the inflorescence and it looks like it might be male-sterile, judging by the tiny stamens.

... along with field scabious .....

... flowering in profusion in the meadows at the end of Hawthorn Dene ...

... where there are some fine specimens of giant bellflower.

I suspect that alkaline soil might be the reason for the very blue hue of the tufted vetch on the cliffs but .... 

... this unusually pale betony plant (normal flower behind) is probably a genetic mutation.

Bloody crane'sbill always puts on a good show ....

.... and this year centaury has done well too, with some very floriferous plants ...

This is hemp agrimony .....a major constituent of the taller vegetation while .....

.... hoary plantain is blooming down amongst the grasses.

Plenty of knapweed Centaurea nigra, alongside the ....

.... greater knapweed Centaurea scabiosa.

Drifts of marjoram aka oregano (crush the leaves and sniff for a tantalising hint of Mediterranean cuisine!)....

Spear thistle already running to seed ....

.... likewise agrimony, producing its little bell-shaped hooked fruits ....

Yellow loosestrife ....

.... and some wonderfully robust specimens of yellow-wort, with its strange glaucous, stalkless leaves.

In dry summers yellow-wort, which is an annual, is often a stunted plant and only produces a few flowers - but this year some plants have responded to the rain with a wonderful display...

... and the North Sea provides a fine backdrop for the floral spectacle ....

..... and for haymaking ....

Road Verge Wild flowers

Most of the major road verges around here have been mown but on some of the unmolested minor roads and farm tracks there are fine displays of wild flowers - like this handsome patch of giant bellflower Campanula latifolia in a farm gateway near Wolsingham.

This was the finest specimen of spotted orchid that I've seen this year, growing all on its own beside a minor road near Crook. This was the only spotted orchid that I spotted along a mile of verge - all on its own. But that's the magic of orchids - their minute wind-blown seeds can land almost anywhere.

The same verge hosted masses of tufted vetch Vicia cracca, climbing up through the hedgerow and a great attraction for bumblebees.

The Bells! The Bells!

There are two Campanula species that flower around haymaking time in Weardale. This is giant bellflower C.latifolia, which favours shady verges and - in this case - a permanently moist corner of a field near Stanhope Dene.

Harebell C. rotundifolia is characteristic of dry grassland, where its slender stems mean that the bells constantly dance in the wind, and there are some lovely patches of it around some Weardale haymeadows where ...

.... farmers have been turning the new-mown hay, hoping that it will dry in the sun before wet weather arrives.

Ghosts of 2009..

Down amongst the dead leaves left over from last autumn lie the skeletal remains of last summer's wild flowers. We found this partially decayed seed head of giant bellflower Campanula latifolia in the woodland beside the old railway line that leads to the Nine Arches viaduct in the Derwentside Country Park , where the green shoots of this year's plants are already beginning to sprout.

All the softer tissues in the seed capsules have rotted away, leaving the network of tough-walled xylem vessels - the internal plumbing system that that supplied the developing seeds with water. Double-click for larger, clearer images.