Nettle tap moth Anthophila fabriciana

This is the bivouac of a nettle tap moth caterpillar Anthophila fabriciana, which builds itself a temporary home by folding a stinging nettle leaf and stitching it together with silken thread.

Stinging nettle food plants are ubiquitous and this must be one of our commonest micro-moths, It produces two broods a year and the adult day-flying moths (see below) sometimes appear in very large numbers. The earliest brood to emerge often feeds on cow parsley and hogweed umbels.

Nettle and meadowsweet galls

These strange swellings on leaves and leaf petioles of stinging nettle are the work of a gall midge called Dasyneura urticae, whose larvae develop inside the pouches. The midge lays its eggs on the leaf upper surface and when the larvae hatch they irritate the plant tissue on either side of the the groove in the leaf ribs, which grows over them forming a protective pouch lined with nutritive tissue. When the larvae are fully developed they escape through a slit in the gall wall and fall to the ground, pupating in the soil. 

You can find some excellent photos of the midge and its larvae at this web site

These are gall midge galls of another species of the same genus, Dasyneura ulmaria, on the leaf of meadowsweet Filipendula ulmaria. The galls and life cycle of the insect are broadly similar but in this case the midge lays its eggs on the underside of the leaf and there is only one generation each year.

All photos taken at Romaldkirk in Teesdale on 25th. September.

More photos of plant galls here.

Nettle-tap micro-moth

No Nettles Required: The Reassuring Truth about Wildlife Gardening, by Dr. Ken Thompson, is one of the best books about wildlife gardening that I have encountered, largely because it's based on his several years of research into wildlife in gardens in Sheffield. Many wildlife gardening books simply trot out the same old formulaic advice that's recycled from earlier books, or are based on wishful thinking rather than real experience. Thompson's book is full of sound advice about how to integrate elements of wildlife gardening into a plot that produces food and is aesthetically pleasing; it has probably converted a lot of people to a more wildlife-friendly form of gardening who might otherwise have been put off by the thought of accommodating nettles.

One of the points he makes in his book is that cultivating nettles in the hope that nettle-breeding butterflies like peacocks, small tortoiseshells and commas will colonise them isn't a core activity for the wildlife gardener - there's no shortage of nettles in the wider countryside and on waste ground everywhere and these butterflies most often choose large swathes of nettles to lay their eggs on, rather than small patches in corners of typical gardens. There are better ways to use gardens to encourage wildlife to take up residence - like making sure there's a pond, a log pile, some long grass and plenty of pollen- and nectar-producing flowers (which don't necessarily need to be natives).

Of course nettles have an extensive insect fauna (explored in B.N.K Davis's book Insects on Nettles), in addition to the butterflies mentioned above, but some of the common nettle specialists visit nettle-free gardens to feed even it there are no host plants to lay their eggs on. We've had large numbers of this day-flying micro-moth, the nettle-tap Anthophila fabriciana , in our garden this year even though it's a nettle-free zone. They come for the easily-accessible nectar in plants like this cow parsley - you can see the moth's proboscis sucking up nectar in the top picture.The moth's generic name - Anthophila - means 'flower lover'.

Rusty nettles

The recent warm, humid weather has provided excellent conditions for the development of stinging nettle rust fungus Puccinia urticata and there are some colourful infestations on our local nettle patches.

The disease tends to produced flattened, distorted stems and also .....

... patches of spore cups on the underside of the leaves. 

For a close-up view of the spore cups and their contents in a related species of rust fungus, click here.

Wildlife Viewed Through Beer Goggles: Stinging Nettles

My exploration of wildlife-themed beers has stalled a bit recently but here's an interesting example, brewed with additional stinging nettle flavouring, which adds a frisson of excitement to a quiet pint. Here's what the brewer, based at Matfen in Northumberland, says about it:

Nettle Ale 4.5% ABV

This ale can only be produced in the Spring, when the nettles on the farm are at the perfect stage to be picked. Based on a 14th century recipe, this ale is supposed to help the common cold and gout!

I haven't had a cold since I drank this and I haven't got gout (yet), so it clearly does exactly what it says on the bottle.

Stinging nettles are famous for the wealth of wildlife that they support, including numerous insects, of which thetiny  nettle tap moth Anthophila fabriciana (above) is one, currently breeding on the nettles in my garden. 


More wildlife-themed beers here.

Stinger

A stinging nettle Urtica dioica, spot-lit in a sun-fleck in the woods beside the River Swale, near Reeth this morning

Cycles of Abundance

As spring drifts into summer new insects appear on the scene, briefly flourish and then give way to another species. Recently we've had a virtual plague of St. Mark's flies, whose mating flights are beautifully described by Mark Cocker in today's Guardian Country Diary. This week, in my area at least, it's time for a mass emergence of this...

.....little metallic green weevil that seems to be on every stinging nettle leaf. It's Phyllobius pomaceus (identified with the help of B.N. Davis's excellent Insects of Nettles (Richmond Publishing Co. 1991)). This little weevil breeds on nettles, feeding on the leaves and at the moment every nettle bed has scores of them mating amongst the forest of stinging hairs on the host plant's leaves. They have a short season as adults and will have vanished again by early June, when their larvae feed underground.

This one has strayed onto a hawthorn leaf, overhanging the nettle bed.