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.

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.

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.