Alexanders

Alexanders (Smyrnium olusatrum)

When it comes to invasive species that try hard to take over the garden, there are few things that beat Alexanders (Smyrnium olusatrum). Native to the Mediterranean region, it was brought to the UK by the Romans, back when the islands were still part of the vast Roman Empire. Presumably because of where it evolved, it's sensitive to frosts, and is most common along the UK's coastlines, where frosts are less frequent. It currently smothers roadsides and cliff edges across much of Wales, southern England and eastern Ireland.

Alexanders are vigorous biennials. In the first year, they send up a spray of leaves about a foot high. The second year is when they really come into their own, shooting up to 5-feet tall or more. Covered by scores of umbellate flowers (many branches coming from the same point, like an umbrella), they are a major draw for pollinators from March to June. Many of our early-season insect photos are taken on their flowerheads. The plants are incredibly hard to get rid of; their roots are strong and deep, with a taproot that looks like a particularly fat parsnip. We've found that leaving them until the plant has gone to seed helps, as the root starts to shrink then. But then we have to be sure to grub them out before their thousands of jet-black seeds drop off !

Alexanders is a relative of celery, and was widely used in cooking as recently as the 1700s. It's said to taste either like a cross between celery and parsley or like angelica. All parts of the plant are edible. Though used in the past to treat wounds, asthma and menstrual problems, it is no longer considered to be a medicinal plant. Much as we struggle to control it, we'll probably continue to allow a few to flourish each year — just to provide something for all those early-season insects to eat.

The umbellate flowers of Alexanders

Walnut Orbweb

Walnut Orbweb Spider (Nuctenea umbratica)

An early breakfast out on the "raptor mound" recently revealed a new species for the garden: the abundantly widespread Walnut Orbweb Spider (Nuctenea umbratica). It was headed back to its daytime hiding place behind a slab of bark, which is slowly separating from the decaying stump of a long-dead Leylandi at the edge of the property. That's one of its favoured hiding spots, apparently; away from buildings, this species is often associated with dead wood. During the day, it hides away. At night, it crawls out and spins a large orb web — the familiar, tidy, circular web we all know and recognise as the classic spiderweb. Then it sits at the centre of that web, waiting for unwary nocturnal insects to blunder into the sticky strands. As with all spiders, the female is larger than the male. Other than that, the sexes are similar in appearance. Their dark colouration, "leathery" look, and distinctively flattened shape help to identify them, as do four pairs of small "dimples" that run down either side of their centre line. Females are found virtually every month of the year, though far less commonly in December and January. Males are more typically summer creatures, with most appearing from May to September. We have lots of time to enjoy these handsome creatures then — here's hoping they don't get too close to our moth trap!

Garlic Mustard

Garlic Mustard (Alliaria petiolata)

One of the plants with a toehold in the wild corner of the garden (with a few stragglers that have made it into the main bed as well) is Garlic Mustard. Having come from North America, where this plant is a major invasive problem, I was ready to yank out every last one. But here on its native turf it's a reasonably well-behaved biennial, so we've let it be. Last year, these plants were low-growing rosettes of green leaves. This year, they've shot upwards, crowned with the four-petalled flowers that show them to be members of the family Brassicaceae (the cabbages and mustards). Despite the fact that they have a scientific name that means "onion-like" — and smell strongly of garlic — they're not related to either onions or garlic.

We're leaving the plants in place because they're the larval food source for the Orange Tip and the Green-veined White (two butterflies we see regularly in the garden) and for the Garden Carpet (a moth we caught in our trap several times last year). In fact, nearly 70 species of various sorts are known to feed on the plant, at least seven fungus species are associated with it, and hoverflies and midges take nectar from the flowers. Humans too have been known to munch on it. Garlic Mustard is one of Europe's oldest spices, with evidence of it being used as long ago as 4100 BC; ancient pottery from Germany and Denmark contains traces of the plant. European colonists took it with them to the New World when they settled there, using it for both food and medicine. The leaves and seeds are still eaten today, though its medicinal uses (as a diuretic and disinfectant, and sometimes for the treatment of wounds) have fallen by the wayside. Garlic Mustard is found in hedgerows and along wood edges throughout the UK, particularly in England and Wales. Now we'll have to keep our eyes peeled for caterpillars.

Muslin

Muslin Moth (Diaphora mendica)

We added another new moth to the garden list last week: Muslin Moth (Diaphora mendica). This one is a male, identified by those dark grey-brown wings (with a specific arrangement of black dots) and those feathery antennae. A female's wings would be a somewhat translucent white and her antennae would be simple and straight. Muslin Moths overwinter as pupae, wrapped in the case the caterpillar creates to metamorphose into an adult. Most emerge to fly as adults between late April and June, so ours was a wee bit early. They're common and widespread in England and Wales, less so in Scotland and Ireland, occuring in woodlands, downland, sand dunes, hedgerows and gardens. Larvae feed on many common, low-growing "weeds", including dandelions, plantains, chickweeds, docks, heathers and some sallows, so they should feel right at home in our garden. Intriguingly, according to the Butterfly Conservation website, females fly by day and males by night, so how they ever find each other is beyond me!

Angle Shades

Angle Shades (Phlogophora meticulosa)

We ran our moth trap for the second time this year last week, and this lovely Angle Shades (Phlogophora meticulosa) was one of the beauties attracted to the light. Its habit of sitting with its wings partially rolled up lengthwise is distinctive, helping to camouflage the moth by making it look like a bit of old, dead leaf. It's common and widespread across much of the UK, but is most abundant in the south. It's also a strong migrant, and sometimes arrives in sizable numbers from the continent, concentrating along the coasts. Habitats include woodlands, fens, hedgerows and gardens. Adults prefer the flowers of Common Reed (found in abundance in a nearby pond) and various other grasses. Caterpillars feed on a whole host of plants, including many (such as Common Nettle, Bramble and Broad-leafed Dock) found in the wild corners of our garden. Both larvae and adult serve as food for parasitoid wasps, birds, ground beetles and hedgehogs — and don't we wish we'd see some of the latter here! Though their main flight period extends from March to October, adult Angle Shades can be found at any time of the year. The Butterfly Conservation website says the species overwinters as larvae, so this one must have got an early start on metamorphosis.

Queen Bee

Buff-tailed Bumblebee (Bombus terrestris) on Japanese Skimmia (Skimmia japonica)

Now that the weather is warming up, bees are visiting the garden in ever-increasing numbers. Queen Buff-tailed Bumblebees (Bombus terrestris) were among the first to appear, lumbering through the flowering Red Dead-nettle plants as early as March. Queens are the only ones to overwinter, and they're easy to tell from workers and males (which will appear later in the season) by their larger size. The narrow brown neck band, golden-brown "girdle" and buffy tail tip of the individual above help to identify it as belonging to the subspecies audax, which is found only in Britain. The large size and dense "fur" of Buff-tailed Bumblebees allow them to continue foraging when temperatures are as low as 50F (10C), when most other bees become inactive. This is one of lowland Britain's commonest bumblebees, found in a wide variety of habitats, including urban areas. It's rarer in the mountains and on offshore islands. Native to the western Palearctic, it's widespread and abundant across most of lowland Europe and northern Africa as well.

Buff-tailed Bumblebees are general pollinators, visiting a wide variety of flowering plants. In fact, they've been introduced to countries around the globe — including Japan, Argentina, Brazil, New Zealand and Mexico — primarily to pollinate greenhouse crops. Some individuals from those introductions have escaped to create feral populations, and the species is considered invasive in some areas. Wild Buff-tailed Bumblebees typically nest underground in old rodent burrows. Mated queens emerge from hibernation and set up new colonies, rearing worker daughters and (later in the summer) males. New queens and males emerge by mid-summer to mate. The newly mated queens will then hibernate over winter, while the rest of the colony dies. I've seen several queens investigating various holes in the garden this week — including a few checking out the entrance holes to our occupied nest boxes!

Skeletons

Apple-leaf Skeletoniser (Choreutis pariana) on Common Alexanders (Smyrnium olusatrum)

While munching my breakfast on our "raptor lookout" the other morning, I happened to spot this tiny moth (which measures about 1/4-inch) resting on some nearby Alexanders flowers. It's an Apple-leaf Skeletoniser (Choreutis pariana), and it's a new one for the garden. The adult is a nectar feeder, which explains its presence on the flower head. The species gets its name from its caterpillars, which feed on the leaves of apple trees, and also occasionally on the leaves of pears, rowans and hawthorns. The larvae spin a silk web on the upper surface of a leaf, and feed on that surface, leaving only the veins untouched — e.g. skeletonising it.

Though it occurs across much of Great Britain, the Apple-leaf Skeletoniser is a localised species, particularly in Wales and in the north. According to our copy of Field Guide to the Micro-moths of Great Britain and Ireland, its habitats include woodland, scrub, gardens, and urban trees. It can be very variable in colour, with individuals ranging from shades of bright orange (like this one) through reddish-brown to greyish-brown. Many show a wavy dark line towards the base of the forewing (i.e. closer to their head) and another black or reddish-brown line five-sixths of the way down the wing. It's a double-brooded species, with the first brood typically flying June-July and the second brood from late-August to March. They overwinter as adults, so ours has presumably recently awoken from its hibernation.

Vicar Thrush

Ring Ouzel (Turdus torquatus)

We were up early yesterday to check the moth trap, which we ran for the second time this spring. As I was gathering up my camera gear in anticipation of getting some photos, Mike came bursting in to the house. "Come quick!" he called. "It's a Rouzel!" Ring Ouzels (Turdus torquatus) are migrants here in southeastern England. This bird was on his way from wintering grounds in North Africa to breeding grounds in Scotland or northern England. On migration, Rouzels are found along the country's southern and eastern coasts, typically in areas of short grass. This fellow paused for only 15 minutes or so, flitting around in various treetops (and on the telephone wire right above our shed) and singing challenges; I guess his hormone level is high, since he's certainly not going to breed anywhere near here!

Here in the UK, Ring Ouzels breed principally in the uplands, though they do descend almost to sea level in the farthest northern stretches of Scotland. They prefer steep-sided valleys and gullies, building their nests in heather clumps, crevices, or (very occasionally) in trees. They breed from mid-April to mid-July, managing to produce two broods most years. They feed on insects and berries, keying on earthworms in the spring and juniper berries in the autumn. The RSPB (Royal Society for the Protection of Birds) estimates there are some 6300 pairs of Ring Ouzels breeding in Britain — a number which earns them a "red" conservation status, meaning they're in urgent need of conservation action. Like many of the country's other upland species, this one is in pretty steep decline, with a 43% drop in their numbers over the past 40 years.

To hear what they sound like, click the link below; this is a recording I made of the bird in our garden.

Spike

Dark-edged Bee-fly (Bombylius major)

Now that the weather's warming up, we've started to see Dark-edged Bee-flies (Bombylius major) sunning themselves in sheltered parts of the garden. They look mighty scary to the uninitiated — as if they might stick that long, slender proboscis into some tender part of a human's anatomy, rather like a mosquito might. But they're not blood-suckers. Instead, they feed primarily on nectar, and are important general pollinators of low-growing flowers. They also eat pollen, with females consuming far more than males. Their long proboscis allows them to feed more safely, potentially avoiding predators like crab spiders and ambush bugs that might be lurking on the flowers. They're often seen hovering in place with a high-pitched whine, and with their long legs dangling.

Bee-flies get their name from their furry bodies, which resemble those of various bumblebees. Though they're harmless to humans, they aren't quite so innocuous when it comes to bees. Females flick their eggs into the burrows of solitary bee species (particularly mining bees), and the hatched bee-fly larvae feed on both the bee larvae and the food stores left by the bees for their own offspring. The Dark-edged Bee-fly is found across much of the northern hemisphere. In the UK, it's common and widespread (particularly in the south), and found in a variety of habitats, including (obviously) gardens. Adults fly from late-March to June, so we've got plenty of time ahead to enjoy them.