Stinging nettles grow in a wide range of natural habitats, river banks, swamps, meadows, wastelands, floodplains, disturbed areas and gardens. They are are particularly effective colonisers of disturbed, bare or ‘waste’ ground. They flourish in nitrogen-rich soils.  Their seeds can lie dormant in the soil for some five years (and can even survive soaking in salty water), plus they spread using their underground rhizomes. Nettles may not be the most friendly plants to us, as their leaves and stems are ‘armed’ with special ‘hairs’. The hair-like structures are termed trichomes and each trichome has a hollow tube-like structure. At the bottom of the tube is a swollen base, which is filled with a number of chemicals, (including histamine, serotonin, formic acid and acetylcholine). The tip of the tube is easily broken, leaving a sharp point that can penetrate the skin and deliver the ‘biochemical cocktail’. [caption id="attachment_7154" align="aligncenter" width="600"] Trichomes - loaded with their chemical 'cocktail'[/caption] [NB: there is a video on YouTube that shows this mechanism here.] This collection of chemicals gives the characteristic rash/inflammation of a nettle sting.  Nettles may be found near to dock leaves which, if crushed and rubbed where you have been stung by the nettle, may take away some of the pain. More detailed information on the chemistry of the 'chemicals' in the nettles can be found here.  The hairs / trichomes probably evolved as a defence mechanism to limit grazing by sheep, deer or rabbits. Despite their ‘weaponised hairs’, nettles are in fact very good for wildlife, particularly in urban / sub-urban areas.   This is also true in areas under intensive farming practices.  The spread of farming, urban sprawl, habitat fragmentation and pollution have all contributed to the loss of natural habitats (for plants and animals), and that’s without mentioning climate change. Stinging nettles are the food plant for the caterpillars of comma, painted lady, peacock, red admiral and small tortoiseshell butterflies. The presence of nettles in our gardens and urban areas has allowed these butterflies in. And it’s not just butterflies that rely on nettles. For example,  ladybirds often lay eggs on nettle leaves. This insect might be termed a “gardener’s friend” as it has a voracious appetite for aphids - greenflies and blackflies that suck the sap from plants, ravage the vegetables in our gardens / allotments, Some aphids spread plant viruses, for example, virus yellows on sugar beet. Having nettles in our gardens and near farms give ladybirds and other insects somewhere to shelter, ready to feast when the aphid population rises. Aphid populations can rise very quickly as females give birth to live young, without fertilisation. Nettles can be used to make tea, soup, flavour beer, wrap cheese (Cornish yarg) or make cloth.  Using nettle fibres to make fabric / clothing is a very old practice, dating back to the Bronze Age.  Nettles can also be used to dye fabric [caption id="attachment_34107" align="aligncenter" width="650"] stinging nettle[/caption]

Solar farms have sprung up across the country with hundreds or thousands of solar panels, linked together in fields.  Now, researchers in the States have shown that sowing grasses and wild flowers in-between the panels on solar farms resulted in: A significant increase in the number of beneficial insects (bees in particular benefitted) An increase in insect diversity beneficial 'spillover effects' on adjacent farmland. The solar farms under study were sown with specially designed seed mixes. See also the previous woodlands  blog on solar panels and wildlife The seeding of solar farms would seem to offer support to : Renewable Energy Generation: Biodiversity Pollination services Habitat restoration: in fields that may have been damaged by intensive agriculture and / or development. They can also act as a refuge for native plants and wildlife. Erosion control: the root systems of native plant species (which penetrate to different depths) help prevent soil erosion. Reduced maintenance costs: as less mowing / weed control needed. The cabbage white butterfly is generally regarded as the enemy by the keen vegetable gardener.  If you are growing brassicas - cabbages, cauliflowers, brussels sprouts, broccoli, kale or pak choi, it is likely that you will have these butterflies as summer visitors.  The butterfly is white with black spots on the wings.  Males have a single spot on each of the forewings, whereas the females have paired spots. The butterflies are attracted to the plants as they produce the chemical - glucobrassicin. The butterflies can sense the glucobrassicin through the hairs on their front legs (they have three pairs of legs, a pair on each segment of the thorax). This chemical, glucobrassin, stimulates them to lay their eggs on the leaves of cabbage and other brassicas.  A female can lay up to 800 yellow eggs. These eggs may hatch and the green / black caterpillars emerge.  These caterpillars can double their mass in a day through their voracious feeding.  The adults are attracted to the glucobrassicin in the brassicas just as the caterpillars ‘enjoy’ the chemical - SINIGRIN.   When leaf tissue is damaged, the sinigrin is broken down into a mustard oil, responsible for the pungent taste of Cruciferous vegetables. There are a number of strategies that may help keep the butterfliess away from your crops, and reduce the damage by the caterpillars. Cover the plants with an insect proof mesh Offer ‘sacrificial brassicas’ away from the main crop Use companion / mixed planting, so that beneficial insects have 'hiding places' and it is more difficult for the female cabbage whites to find the brassicas.  Also, by mixing up the planting with herbs and other veg, it makes it a bit more difficult for the caterpillars to move from cabbage to cabbage etc. If you do need to use an insecticide, consider using the products derived from Bacillus thuringiensis.

An obvious answer to this question would be - caterpillars.  But when did butterflies first appear?  There are now some 160,000 species of moths and butterflies -worldwide.  Seemingly, they appeared some 100 million years ago  - in North America.  They evolved from nocturnal moths in the period when flowering plants were undergoing a major expansion (in the Cretaceous period).  Butterflies may have become diurnal to avoid predation by bats, or it may have been to take advantage of nectar production and availability [using the proboscis]. The butterflies and their caterpillars were able exploit the diverse range of food resources that these ‘new’ plants offered.  Butterflies moved out from North America to South America and then on to other parts of the world, though they probably did not arrive in Europe until some 17 million years ago. The evolutionary expansion of the butterflies has been investigated by researchers at the University of Florida; they analysed the genetic makeup of many species (from 90 countries).  They were able to build up a picture of the relationships between the various groups of butterflies and also determined their evolutionary point of origin.  They also catalogued the plants eaten by the caterpillars and it was found that some two thirds of butterfly caterpillars feed on plants from the legume family (the Fabaceae - peas and beans).  It is probable that the first butterfly caterpillars also fed on these plants. Research at the Georgetown University in Washington DC suggests that larger species of butterfly are ‘coping’ better with higher temperatures, associated with global warming.  Bigger wings seem to offer a greater range of movement and the opportunity to find new and suitable habitats.  Smaller butterflies are not faring so well.  The study involved an analysis of the range of some 90 North American species between 1970 and 2010, during which period the monthly minimum temperature increased by 1.5oF. Others have analysed the butterfly collections at the Natural History Museum, using digital technology.   The Natural History Museum’s British and Irish butterfly (and moth) collection is probably the oldest, largest, and most diverse of its kind in the world; some of the specimens date back over a hundred years The measurements of the various specimens were paired with the temperature that the species would have experienced in its caterpillar stage. It was found that for several species that the adult butterfly size increased as the temperature increased (during late larval stage). So, it may be that we will see a gradual increase in butterfly size as temperatures increase with global warming. Join the Big Butterfly Count ? Between Friday 14th July and Sunday 6th August , the big butterfly count will take place.   For full details visit : https://bigbutterflycount.butterfly-conservation.org/about Thanks to Angus for images.

The first few weeks of owning a patch of woodland feel like the beginning of a long and special relationship. Every discovery is new; each adventure a first. A wood reveals it secrets slowly.   We’ve already tramped round every corner of the wood, tearing our shins on brambles, sniffing at fungi, clambering round stumps and totting up the oak, hazel, maple, cherry and rowan that thrive under our canopy of pine and larch. We’ve sat and looked and listened in all weathers, at every time of day. Starting a list of birds was the first thing to do: a mewing buzzard overhead, marsh tits pitching in the roving tit flock, the tap of woodpecker and nuthatch. Autumn – though this year so mild and late – soon announced itself with a first skein of pink-footed geese calling high and unseen over the wood, the first redwing chattering at the wood edge… sounds and colours change; the big wheel keeps on turning… We have always loved moths, for their beauty, their ubiquity, their astonishing variety. Moths range in size from the tiny micros whose larvae leave scribbled signatures across the leaves in which they live, to the powerful hawkmoths or that mythic blue-underwinged beauty the Clifden Nonpareil, a creature practically the size of a small bat, and probably the most sought-after moth among the old collectors with, in some years, just a single individual found across the country. For there’s also a rich and often eccentric history of moth recording in this country with most of the larger moths – the macros - having evocative vernacular names (though don’t confuse your Bright-line Brown-eye with a Brown-line Bright-eye!), and an array of techniques for acquiring them from pupa digging, plastering tree trunks with mixtures of treacle and rum, to light. Nowadays, moths are generally photographed and released rather than pinned; recording them is an excellent way of assessing the biodiversity of a site or tracking population changes. It was clearly time to break out the old moth trap.   And so it was that this September for the first time in years we dusted down the generator, filled the trap with fresh egg boxes for the anticipated moths to settle on, spread out our white sheet in a promising looking glade, and hoped to goodness that our 125W mercury vapour bulb would still fire up after all these years… As night came the light shed unfamiliar shadows through the wood; we waited, net in hand, taking care not to look directly at the blazing UV light; waited with a palpable sense of anticipation… what secret would the wood reveal? At first, nothing. And then a first furtive fluttering across the clearing to the trap – probably a Common Marbled Carpet though I’d have to check – and a plumper-bodied moth, and me there wracking my brains: it’s a noctuid, sure, but I’m so rusty – what’s-it-called? Flame? Flame Shoulder? Setaceous Hebrew Character…? ‘What the hell was that?’ said Beth Something ridiculously large had flapped out of the shadows and vanished. Knelt at the trap, I’d glimpsed it too from the corner of my eye. Could it be a hawkmoth on our very first trap, that would be very cool! I grabbed the net; we stood back and waited. I knew we had something beyond the ordinary when Beth yelled ‘There it is!’ and I swung the net and captured it on a second sweep. It was big all right! Anxious not to lose our catch, whatever it was, we shut ourselves in the toolshed and peered into the gently-opening net with our torch… The moth was the shape of a vulcan, practically size of a small bat, and more beautiful than anyone can do justice to: a marbled, lichenous beauty, zig-zagged and pocked and dabbed with greys and whites and blacks and – look! – when those forewings flick open an underwing black and banded with an impossible flash of blue… ‘It’s a Blue Underwing,’ we cried, ‘A Clifden Nonpareil…!’ An entry in my Aurelian’s Fireside Companion describes the experience soberly: ‘For a moment or two we gazed at it in speechless admiration, fearing almost to breathe lest it take flight…’.  I suspect we used a few more expletives than that!   And what a secret to reveal; our first trap in the new wood and we caught probably the best moth we could ever hope to find. One truly without compare.  Soon after the generator packed in; we were plunged into darkness. 2022, it transpires, has been a record year for Clifden Nonpareils, as it has been for many rare moths. Our Nonpareil could have been a wanderer from further south in England where a population has now reestablished itself on aspen and poplar after decades of extinction – or (and I find this the more romantic possibility) it could have been a migrant from the east, flapping its way across the North Sea to our northerly inland wood, and revealing itself, albeit briefly, to its astonished and delighted admirers…  By torchlight, we placed the moth on a tree stump, astounded to see something we’d always dreamt of finding. It sat there for a moment, as though contemplative, then showed a flash of blue petticoat as it shivered its huge and brindled grey wings. Shivered again. And flew off into the night. What will the seasons bring?

The results of this year’s Big Butterfly Count have now been published and the ‘top’ 5 butterflies are the gatekeeper, the large white, the small white, the meadow brown and the red admiral.  The count is a UK-wide survey that aims to provide a measure of the state / health of our environment by simply counting the number and type of butterflies (and some day-flying moths) we see in our gardens and parks. The good news is that the Gatekeeper is making something of a comeback, being the most spotted butterfly in the count.  The numbers of the Common Blue, Holly Blue and the Comma are also ‘on the up’.  The Comma has been making a slow comeback for some years.  This is associated with the Comma extending its range northwards.  Extension of range is also seen in the Holly Blue, it is thought to be associated with climate change.  Some twenty years ago, it was rarely to be seen in Scotland, but it was recorded in Edinburgh in 2006, then Ayr in 2008 and now has spread across large areas of Scotland.  [caption id="attachment_24954" align="aligncenter" width="600"] Comma butterfly : photo by A J Symons.[/caption] The Jersey Tiger Moth is another species that is extending its range. Once it was to be found on Devon’s south coast, but it has spread north and east.  It is now to be seen in gardens and parks in the Greater London area. These moths ‘like’ gardens, hedgerows and disturbed / rough ground. In coastal areas, they may be seen on cliffs and the upper reaches of a beach.  The caterpillars of this moth feed mainly on ground ivy, white dead-nettle, bramble and the common nettle.    There are differences between butterflies and moth, but there is no hard and fast rule to distinguish between them. Butterflies usually have ‘club-shaped’ antennae, whilst many moths have feathery or tapering ones.   Butterflies normally fold their wings vertically over their backs,  moths generally place their wings horizontally when at rest (but not all). Whilst this summer’s results offer some hope, and the warmth of this summer’s weather might be thought to have favoured butterflies, the overall trend / pattern of butterfly numbers is one of decline - for example, numbers of the Red Admiral and Meadow Brown are down, sadly a pattern seen in many insect species. The loss of suitable habitats, such as meadows and hedgerows, is thought to be a major factor in this decline.

Ragwort is a common wild flower.  Its common names include, common ragwort, stinking willie and tansy ragwort (though its resemblance to true tansy is rather superficial).  It is not particularly a woodland plant, it is found in dry, open places - on waste land, waysides and (grazing) pastures.  It is not a plant favoured by land owners because it has toxic effects on cattle and horses.  It is generally considered to be a biennial, but can persist for some years. The stems are erect, straight, basically hairless.  The actual plant may grow to a height of two metres.  The leaves are lobed in a ‘pinnate’ fashion and have a distinctive smell that has lead to some of its common names - such as stinking willie.   The ragwort is a member of the daisy family (Compositae, now the Asteraceae), and its flowers are massed together into dense, flat topped clusters.  Each ‘flower’ is made up of many small, individual florets.  In the centre are the disc florets whilst around the edge are the ray florets.  The latter have a large lip or flap, which serves to increase the visibility of the plant to pollinators.  During the flowering season, a plant may produce many thousands of seeds.  The seeds have hairs attached to them, which help in dispersal. Ragwort is a plant that is much loved by pollinators - bees, flies, moths and butterflies.  It is generous in its nectar production, and has been placed in the top ten of nectar producers by one survey.   The plant also provides home and / or a food source for many invertebrate species, some of which feed on ragwort exclusively*, including some species on the IUCN RED LIST.  One species that is reliant of this plant is the cinnabar moth, whose status is described as ‘common and widespread, but rapidly declining”.  Interestingly, the cinnabar moth feeds on the plant absorbing the alkaloids and these make it distasteful to its predators . However, important as the plant is in ecological terms, it is toxic as it contains a number of alkaloids.  These are poisonous to various animals, such as horses and cattle.  The bitter taste is a ‘disincentive’ to much of the plant being eaten.  However, because of the alkaloids, it is one of the five plants (in the UK) named as ‘an injurious weed’ [as defined by the Weeds Act of 1959].  Some people may suffer an allergic reaction after handling the plant, experiencing a form of dermatitis. [caption id="attachment_38929" align="aligncenter" width="675"] Cinnabar moth, image courtesy of mcbeaner on Pixabay.[/caption] Further information on the Ragwortis available on WoodlandsTV, see below [embed]https://youtu.be/esfLW0nIvNo?si=DQ2Uokq7U1pAJYMZ[/embed] [caption id="attachment_38599" align="alignleft" width="300"] Cinnabar caterpillar[/caption] [caption id="attachment_38566" align="alignright" width="300"] Leaves of Ragwort[/caption]  

Butterfly Conservation has organised the Big Butterfly Count for the last twelve years.  This year, the count took place between 16th July and August 8th.  The count gives some information of how butterfly and moth populations are faring.  Both butterfly and moth numbers give us some information about the ‘health’ of our environment, and indeed what has been termed the insect apocalypse. Though some 150,000 counts were registered this year, the ‘average’ number of butterflies / moths recorded per count was nine. This was down from the average count of 11 last year,  and 16 in 2019.   The total number of butterflies / moths counted was down by some 14% overall compared to last year. Those species that had significantly reduced counts were Peacock down by 64% Common Blue down by 59% Speckled wood was down by 41% Small tortoiseshell and the Comma dropped by 32% On a more positive note, the ringlet and marbled white were recorded in greater numbers (but they did have low counts last year). The Spring weather was probably a significant factor in these generally disappointing results.  The wet May would not have helped breeding or feeding; low temperatures are not conducive to activity.  The poor weather would particularly impact on those species that normally produce two broads a year.   Further information on the results of the count can be found the Butterfly Conservation website :  here.

Big Garden Birdwatch.  Once again the RSPB’s Big Garden Birdwatch is about to swing into action.  This year , it will take place from the 29th to the 31st of this month.  To take part, you just need to count the birds that you see in one hour.   Details and guidance are available here : https://www.rspb.org.uk/get-involved/activities/birdwatch/everything-you-need-to-know-about-big-garden-birdwatch/  Butterflies (and moths).   If you are interested in adding to your knowledge of wildlife, then the Butterfly Conservation people not only offer guidance on identifying moths Read more...