Friday, 29 August 2014

Brown's Road

Inevitably, moving house ends with the dumping - sorry, recycling - of much rubbish. The recycling depot in Daventry is in Brown's Road, and today we made our fourth (or is it fifth?) visit. Chris dropped me off there (no comments please) and continued to Byfield; I made my way home.

Before leaving Brown's Road I had half an hour or so strolling around the area, just being nosy like.  
Sloe Bug on Weld. Daventry, 29 August, 2014

A plant of Weld, Reseda luteola, grew on disturbed ground at the roadside, a typical habitat for this species. On it was a Sloe Bug, Dolycoris baccarum. This is one of the prettiest of the shieldbugs and, although its colours become dull after death, the chequered patterning along the edge of the abdomen still makes it recognisable. Despite its name it is by no means confined to sloes, and will be found on a wide range of plants.

Damage caused by the Viburnum Leaf Beetle.
Brown's Road, Daventry. 29 August, 2014

I crossed the road to inspect a planting of ornamental shrubs. Lots of Viburnum had been included and the tell-tale signs of attack by the Viburnum Leaf Beetle, Pyrrhalta viburni, were everywhere. This insect is a serious problem and has spread rapidly over the past 30-40 years.

Pyrralta viburni mating. Brown's Road, Daventry.
29 August, 2014

It wasn't long before I found examples of the culprit. In fact there were hundreds of them and many, if not most, were mating.

Ichneumon suspiciosus. Brown's Road, Daventry.
29 August, 2014

A handsome ichneumon wasp alighted on a nearby leaf. I don't really deal with these insects, fascinating though they are, but I am reasonably confident that this is Ichneumon suspiciosus. The word ichneumon comes from the Greek, and means "tracker"; these insects track and hunt down insect prey.

Although I don't study Hymenoptera (wasps, bees, ichneumons, etc) I am an enthusiast regarding two-winged flies, i.e. diptera, so when a muscid fly caught my attention I moved to take a closer look.

Musca domestica, Brown's Road, Daventry.
29 August, 2014

In fact it was a Common House Fly, Musca domestica. Hardly worth photographing but it posed so nicely that to ignore it would have been churlish.

Leaves on an oak tree were mottled with unhealthy-looking yellow blotches. This usually indicates that they are bearing galls on the lower surface, so I wasn't surprised when I turned one over.

The galls were the work of a cynipid wasp, Neuroterus quercusbaccarum. It would be a challenge to find an oak tree in southern Britain to find a specimen not afflicted with these galls, yet they probably do little harm. In the form shown it is known as the Oak Spangle gall.

This picture, which I took in mid-April this year, shows a gall formed by the same species of wasp. In this form the gall is known as a Currant Gall and is common on oak catkins in April/May. From the Currant Gall the male and female wasps emerge. They mate and the fertilised eggs are laid on the underside of oak leaves to form, as we have seen, quite different galls. Another generation of the wasps emerge from the Spangle Galls in April to lay eggs on catkins, and the whole cycle starts again. This complicated arrangement is frequent among cynipid wasps and is clearly a successful strategy.

I had set out in cool, grey and windy conditions, but I was hoping that the weather would change. Well, it did change; it began to rain. August in England, heigh-ho! I put my camera away and strode home.

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