Blue

Holly Blue (Celastrina argiolus)

For years now, I've been trying to get a picture of this little butterfly: the Holly Blue (Celastrina argiolus). The problem is that it almost never, EVER alights! Instead, it flits around the garden, touching down (if at all) for only the briefest of moments. About the time the camera focuses, the butterfly is off again. But last week, I got lucky. This female returned again and again to a bush just outside the house, presumably checking it out as a potential site to lay its eggs. The butterfly gets its name from the primary host of its spring larvae. That first generation feeds principally on the buds, berries and terminal leaves of the Holly tree while a second generation, which emerges later in the summer, is found primarily on Ivy. In both generations, larvae will also feed on various other shrubs and vines, including spindles, brambles, dogwoods, snowberries and gorses. Our garden has both Holly and Ivy, plus plenty of brambles, so I'm sure this little female can find somewhere appropriate to lay.

The Holly Blue is one of two blue species we get here. The other, Common Blue, is distinguished by orange spotting on the underwing. Adult Holly Blues emerge earlier in the spring – as early as April, as opposed to June for the Common Blue. According to the Butterfly Conservation's website, the Holly Blue tends to fly higher than other blues, which typically stick close to the ground; maybe that's why I don't seem to see as many of them. They also go through big population swings from year to year, primarily because they're regularly attacked by a parasitoid ichneumon wasp, which lays its eggs in the butterfly's developing caterpillars. The caterpillars serve as the only host for the wasp, so when their numbers inevitably collapse, so does the wasp's population. This allows the butterflies to recover, with the wasp numbers slowly following. And so the cycle continues! The butterfly is common and widespread in England and Wales, and rarer in Scotland and northern Ireland, though it is spreading steadily northwards. Elsewhere, it is common across much of Eurasia – and serves as the national butterfly of Finland.

Boxing day

Box-tree Moth caterpillar (Cydalima perspectalis)

Our poor Box hedge is doomed. Like all of the Box in southern England, it is under attack and daily getting weaker. The culprit? The Box-tree Moth (Cydalima perspectalis), whose voracious caterpillars devour the plant's leaves and sometimes strip the bark from its stems. Native to south-eastern Asia, the moths first arrived in the UK back in 2007, a year after they first arrived in mainland Europe; it's thought they were accidentally imported with shipments of Box from Asia. By 2014, they were well-established in London, and they've been expanding quickly out from there ever since. Though they have a range of natural predators, including parasitic wasps and flies, spiders, ants and some garden birds, they're proving quite difficult to control. Many of the Box hedges in the neighbouring village have been completely decimated, and ours is quickly following suit. Box-tree Moths have at least two generations per year, which compounds the problem. Females lay their rather flat, pale yellow eggs in overlapping rows on Box leaves. Those laid in late summer/autumn overwinter as small, early instar caterpillars, tucked snugly into shelters made of Box leaves webbed together with silk. As the days warm in early spring, they emerge to feast, growing rapidly. By June, the first generation has pupated and emerged as adults. (The rather handsome adult moth is pictured below.) Another generation of adults emerges in late July and August. Though we're hoping for some predator to make short work of our local invaders, we're becoming increasingly resigned to the fact that we'll probably have to eventually replace the hedge.

Adult (Mike's picture)

Turkeytail

Turkeytail (Trametes versicolor)

Spring is finally arriving in our chilly corner of England, and I've been out in the garden for the past few weeks, looking for new species to photograph. The other day, I found this lovely little bracket fungus growing on the stump of a shrub Mike removed last year. It's known as Turkeytail (Trametes versicolor), due to its strong resemblance to a real Wild Turkey's tail. Those concentric rings of colour come in many shades – brown, black, green, purple, grey or yellow – always with a pale outer margin. It's a very common fungus, widespread across the UK and throughout much of the rest of the world, growing on dead wood. Often, there are many tiers stacked up together; ours is a bit on the small side, with only two little caps. They can be seen every month of the year, though they tend to be most colourful (and thus most noticeable) in the autumn. In the past, these pretty little brackets were used as table and hat decorations. A compound extracted from the fungus is used in Japan in the treatment of some forms of cancer, and the fungus itself has been used in traditional medicines in both Japan and China for centuries.