Saturday, 6 July 2019


I took a trip to Matt Moser's farm, Foxhill Farm, yesterday. It was a very warm and gloriously sunny day but, although his hayfields were teeming with Meadow Browns, (the caterpillars feed on grasses) there was a disappointing lack of insect variety. Ox-eye daisies (we called the moon-daisies as children) and black knapweed were there aplenty but receiving few callers. The total number of arthropods (insects, spiders, etc) so far recorded from Foxhill Farm stands at 470. Not bad but there should be quite a few more yet.

Ox-eye Daisies were growing in profusion at Foxhill Farm.
5 July, 2019

One creature added today was Eriosoma lanigerum*. This is an aphid which, because of the cotton-wool-like secretion which it produces from abdominal glands, is known as Woolly Apple Aphid.

Its activities, generally confined to apple, cotoneaster and a few close relatives, result in remarkable growths developing on branches and even the main trunk.
Eriosoma lanigerum causes grotesque growth on apple trees.
Foxhill Farm, Badby, Northants. 5 July, 2019

These growths can be quite grotesque and, if they are found in the winter when there are no aphids to be seen, quite puzzling. (One particularly nasty example in the middle of Daventry's shopping centre has recently been removed.)

The strange woolly aphids are an odd sight, the 'wool' apparently
repelling birds.
They can be controlled by organophosphate pesticides such as parathion and malathion, but these chemicals are being phased out as their cancer-inducing potential is recognised. As an alternative, a chalcid wasp, Aphelinus mali, offers promise of biological control.

Anyway, having photographed the woolly aphids and taken a rather meagre number of insects, I made my way back to the car. I had parked it in a barn and thus in the shade but even so the thermometer was registering 27 degrees.

* Erio, woolly; soma, body; lanigerum, woolly. 'The woolly-bodied creature that is woolly!' Tautologies like this are common in biological nomenclature.

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