Wednesday, September 27, 2023

The Year of the Red Admiral

I can't recall an early autumn when I've seen so many red admiral butterflies. It seems to be an exceptionally good year for them here in County Durham, both in our garden and in the wider countryside. 

A red admiral with its black and scarlet wings outstretched, basking in the afternoon sunshine, is a magnificent sight but the undersides of the the wings have their own distinctive beauty. When they are folded they provide a degree of camouflage, with their dark dead-leaf colours, but closer examination, with the aid of brighter light, reveals an exquisite, intricate pattern of scales in shades of brown, grey, blue and green.

The three plants that attract them most in our garden in September are ice plant Hylotelephium sp., ivy and Buddleia x weyeriana, but they also congregate in the company of comma butterflies on rotting fallen apples and pears, becoming sluggish and inebriated under the influence of fermenting juice. 

Sunday, September 24, 2023

Some toadstools from the Tunstall valley, Weardale

 It has been a slow start to the toadstool season hereabouts, but these are a few recent finds from the Tunstall valley in Weardale. They were all photographed in or around Backstone Bank wood, an ancient oak woodland. I'm not 100 per cent sure about the identifications, so would welcome any corrections.

Two brown birch boletes Leccinum scabrum

Smokey bracket Bjerkandera adusta

Felt saddle Helvella macropus, partially excavated from the leaf litter in the top photo, to reveal the stipe

awny grisettes Amanita fulva

An Amanita, probably the panther cap A. pantherina with spot pattern disrupted by rain

A brittlegill Russula sp.

Tiger's eye Coltrichia perennis

.... and one with rather beautiful gills, that I haven't been able to ID yet

Friday, September 22, 2023

The first and the last wild rose

 Burnet rose Rosa pimpinellifolia is always the first wild rose to come into bloom, in late May, and also the last the continue blooming; I have found it in flower on Christmas day in years when the winter is mild. It's currently putting on a fine early-autumn display at my local nature reserve, Durham Wildlife Trust's Low Barns reserve at Witton-le-Wear. On a chilly autumn day just one sniff of its intense scent takes me right back to warm summer afternoons.

Rosa pimpinellifolia is the prickliest of all the wild roses and the easiest to identify, because the hips ripen to deep purple and then to black as autumn progresses. It's most often found on coastal sites, in sea cliffs and sand dunes, but there are a few places in Weardale where it grows in hedgerows. Some of these are close to habitation, which may be a reflection of it being cultivated in the past and then escaping back into the wild. These days, most gardeners would find it too invasive because it suckers freely, but cultivars known as Scotch roses have been grown for centuries, as Rosa spinosissima.

Monday, September 18, 2023

Silver birch seeds

 Silver birch seed catkins are ripening now and fall apart at the slightest touch. Their seeds are an important food resource for several small finches, including siskins, goldfinches and redpolls.

When the catkins disintegrate they separate into woody, arrow-shaped bracts, releasing the much smaller seeds that are surrounded by a broad translucent wing. They can be carried long distances on a windy day - one of the factors that make this tree such a prolific coloniser of open habitats.

Saturday, September 16, 2023

Bumblebees' worn-out wings

 By this stage in the year a lot of bumblebees are reaching the end of their lives. They take longer to warm up after cold nights and begin active feeding, and there are fewer flowers available so nectar can be harder to find. 

Like many, these have lost quite of lot of their fur and what remains has become sun-bleached. A close look at their wings reveals a lot of wear-and-tear, with fraying at their tips where they have been beating and up to 200 times per second and made contact with hard objects. It's said that the average life of a worker bumblebee is about one month. These are simply worn out, from provisioning colonies that are now in steep decline; soon only the new queens will be left, to crawl away into secure hibernation sites until spring arrives and the whole cycle begins again.

Friday, September 15, 2023

Autumn seed dispensers - beautifully functional natural architecture

 Seeds' pods and capsules are remarkable examples of beautiful, functional natural architecture. The two photographs below show what happens when seed pods of American willowherb Epilobium ciliatum are ripe. The pod splits longitudinally into four sections that gradually curl backways, dragging with them the hairy 'parachute' plumes of the rows of seeds, which eventually break free and are carried away on the wind. 

Mouse-ear chickweed carries its seeds inside a translucent, flask-shaped capsule which has a ring of teeth around the opening. The teeth respond to changes in surrounding moisture, opening to release seeds when they dry out.

Cowslip seed capsules (below) also open via a ring of teeth that curl backwards in dry air. These capsules are still full of seeds which, after shedding, will usually remain dormant in the soil until spring, needing the low temperatures of winter to break their dormancy.

Monday, September 11, 2023

The spider season

 There are some fascinating spiders around at this time of the year. This little beauty is a zebra spider, that lives in my greenhouse. It doesn't make a web, it leaps on its prey. The forward-facing pair of its eight eyes are especially large, giving it binocular forward vision and the ability to judge distance accurately.

The garden spider below has spun its web in my greenhouse, across the doorway: I have to duck under it to get in and out. I watched as it caught this wasp and wrapped it in a silken shroud in less that 20 seconds. In the second picture you can see the prey's jaws protruding through the silk, as it tried to bite its way out - unsuccessfully.

This house spider, below, had fallen into our bath - probably entering the bathroom through an open window after climbing up the outside wall. It most likely fell in when it tried to drink from the dripping tap. It's now re-housed in the greenhouse.

House spiders look fearsome but they are easy prey for cellar spiders that trap them in their silken threads, using their long legs to drape the thread around their prey, then paralysing it with venom. They guard their captured prey, usually taking a couple of days to eat them, leaving only a few pieces of its exoskeleton. 

Both cellar spiders and crane flies are commonly known as daddy-long-legs but when the two meet (below) the outcome is never in doubt. Most crane flies that find their way into our house end up in a cellar spider's web.