Wood Wasp, Sprouting Loggeries

While doing the Butterfly Transect at the Gunnersbury Triangle, I came across a fairly large Wood Wasp (in the sawfly family), about 25mm long. It was a bit tricky getting a photo,  as these insects are distinctly skittish – they race about in the shadows, occasionally perching on a leaf’s upper surface. The breeze was wafting the branches gently, so patches of sunlight came and went. I shot several images with the miniature camera – it has two big advantages over my full-size SLR: one, it has a very short focal length, so it has a better depth of field than an expensive macro lens; two, it’s small and cheap, so I habitually carry it with me in my rucksack.

Wood Wasp, cf Sirex, on Ivy

The two images here show (left) the resting position with the wings over the body, the long antennae,  the alarming-looking ovipositor, and the orange-brown legs; and (right) the plump black abdomen with white spots. Perhaps the two images show that it’s rather hard to get a single image which is suitable for identification. This one looks like a Sirex so perhaps that’s what it is. The eggs are drilled into wood.

The butterfly transect yielded the first definite Green-Veined Whites, i.e. I was able to get close enough to be sure; until now they’ve all been “Small/Green-veined” worse luck. There were some Speckled Woods and an Orange Tip, too; a Brimstone turned up after I’d put the clipboard away.

Sprouting Loggery
Sprouting Loggery

But the most curious observation of the day was this sprouting loggery. We ‘planted’ (more literally than we knew) the sawn Willow logs in the winter. They seem very happy in their new setting and are growing vigorously. It will be interesting to see how they get on.