Tuesday, June 28, 2016
It's wild rose time and the most fragrant British species by far is burnet rose Rosa pimpinellifolia. It has a strange distribution here in Country Durham - mostly coastal but with a few inland populations - perhaps because people planted it in their gardens in the past. This one was photographed at Durham Wildlife Trust's Low Barns Nature Reserve.
We live in an age dominated by visual images, especially on the internet, but wild flowers can engage all the senses, and especially the sense of smell. A few years ago I found this book -The Scented Wild Flowers of Britain by Roy Genders - in a second-hand bookshop and it opened up a new dimension in botanising. It's not just flowers that are scented - leaves and roots of many species also have their own distinctive aroma.
The problem is that having reached three score years and five my sense of smell isn't as acute as it once was - and the fragrance of many species is quite subtle. Just sniffing the flower when its scent is diluted by the passing breeze isn't enough. So that's why I always carry ......
... a small, screw-top plastic tube. If you just put the flower (in this case red clover which has a delicious peppery sweetness) in this enclosed space for a few minutes the volatile fragrance is concentrated in a small volume of air and is very easy to detect. For leaves, crushing them before you put them in the tube releases the scent much more efficiently.
Fragrances famously stimulate the memory and recollection of past experiences. For me the scent of this plant, meadow rue Thalictrum flavum, brings back memories of bathing our children when they were babies, nearly forty years ago. Its flowers have a comforting, slightly antiseptic smell that mimics the fragrance of the brand of baby talcum powder that we used on them. These days I find it quite difficult to detect the smell of the flower in the open air but when I enclose it in the plastic tube for a minute or two it immediately becomes apparent.
Sunday, June 26, 2016
We found this ghost moth Hepialus humuli on the cliff-top path at Dawdon on the Durham coast this morning.
Ghost moths are unusual in engaging in communal courtship displays at dusk, drawn together in "leks" of a dozen or more by emitting come-hither scents that are said to be reminiscent of the aroma of goats. They hover just above the vegetation, swaying from side to side "as if dangling on the end of a string", according to a 50-year-old account by the eminent entomologist E.B. Ford.
Their ghostly appearance is enhanced by the fact that the undersides of their chalk-white wings are dark brown, so with every upstroke they seem to disappear in the moonlight, then reappear on the downstroke. According to Ford's account their pheromones incite receptive females to fly straight into the swarm of suitors and collide with a chosen male; then both fall to the ground to mate. It's a performance many have described and few have witnessed but one who has is Stephen Cumming, who has posted a video on YouTube that you can watch by clicking here.
Friday, June 24, 2016
I first read Weeds and Aliens, a volume in the New Naturalist series written by Sir Edward Salisbury, a former Director of the Royal Botanic Gardens at Kew, almost fifty years ago. One particular section, where he discussed seeds distributed on footwear, has always stuck in my mind.
Salisbury went to some lengths to demonstrate the effectiveness of seeds dispersal by our feet as we walk around. He even swept up the soil on the floor between the pews of churches after services and germinated seeds of plantains, daisies, irongrass, pearlwort, chickweed and several grasses that had been carried in on the feet of the congregation.
He had a particular bee-in-his-bonnet about Roman soldiers carrying seeds across Britain in mud on their hobnailed sandals.
Early this year after a visit to Hayley Wood in Cambridgeshire I followed Salisbury's example and scraped the mud from my walking boots into a seed tray to see what would germinate. The picture above shows some of the seedlings. So far I've been able to identify:
A willow herb species
4 unidentified seedlings
plus four species of grass that I haven't identified yet.
No real surprises but quite a mixture. The wood is famous for its oxlips but I don't seem to have had any luck picking up their seeds on my boots!
Wednesday, June 22, 2016
From March until July, this has been the best for native tree blossom that I can recall in our part of the North Pennines. It started with sloe and is now coming to an end with elder. Here they are, in chronological sequence
Blackthorn aka Sloe
Wild cherry aka gean
Rowan aka mountain ash
Tuesday, June 21, 2016
Delighted to find this hedgehog in the garden this morning - the first I've seen here for a couple of years.
Hedgehogs are notoriously prone to tick and flea infestations and this one really seemed to be suffering today, stopping several times to have a really good scratch.
You can see in the two photos above how it uses its hind legs alternately to reach up to the middle of its back and rake through its spines.
Those long claws must be quite effective for raking out parasites.
It's certainly not an elegant performance, as you can see from the two photos above. Notice the short, pointed tail - hidden when the animal is on even keel.
I've put a short piece of video of the ungainly grooming performance - click here to watch
Thursday, June 16, 2016
Thursday's Guardian Country Diary is about dung flies Scathophaga stercoraria
These common insects carry out their courtship on dung but are particularly fond of cow-pats. This is a male, awaiting the arrival of females. They prefer fresh dung, before it becomes too crusty, for attracting the females that scent the trysting place from downwind.
Males usually outnumber them so there is intense competition for a mate, which females usually choosing the largest suitors. Their sex lives have been intensively studied because these insects are easy to rear under laboratory conditions - you can read about the intimate details of their mating habits by clicking here.
Their Latin generic name Scathophaga (originally Scatophaga, but it seems to have acquired an additional h) means 'dung-eater' but it is only the larvae, which hatch from eggs laid in animal dung, that do this. The adult flies are formidable hunters, needing to catch and eat other insects to complete their sexual development before they are capable of breeding. This one has caught a small hoverfly and is holding it between its front legs, in much the same way that mantids hold their prey.
Many dung flies suffer a gruesome fate when they are infected with a fungus called Entomophthora. Its hyphae grow into their host through its spiracles and invade its body, digesting it until it weakens. In the final phase the fungus turns its host into a zombie, affecting its nervous system in a way that makes it climb towards the light. The flies die clasping grass stems, where the spores erupt through their body and are passed on to other inquisitive flies that investigate the corpse.
The pictures below, taken using a microscope, show the sticky spores on the dead dung fly host.
Sunday, June 12, 2016
Dry stone walls, and old stone walls held together with mortar, acquire a flora of resilient species that thrive in their damp crevices. In Weardale these vertical gardens are at their best from mid-May to early June, before conditions become too dry.
This beautiful display, with yellow Alyssum saxatile in the foreground, cascades down a wall in Stanhope, Weardale
Fairy foxglove Erinus alpinus covers large areas of old walls in Stanhope.
Ferns colonise walls too, but usually on the side that's shaded from the sun. This is brittle bladder fern Cystopteris fragilis, growing in the wall around St. John's Chapel churchyard in Weardale.
Wall rue Asplenium ruta-muraria and maidenhair spleenwort Asplenium trichomanes sharing the same crevice in a wall at Eggleston in Teesdale
Aubretia and dandelions in a retaining wall near Daddry Shield in Weardale.
Yellow Alyssum saxatile clinging to the narrowest of crevices in Stanhope.
Wallflower Cheiranthus cheiri, living up to its name in Stanhope.
Fairy foxglove Erinus alpinus, on a wall in Stanhope.
Snow-in-summer Cerastium tomentosum on a wall in Stanhope.