Thursday, 25 February 2016

Oaks and Erratics

Kentle Wood is bordered on the west by arable land and I had a good look at it today. I was glad to be wearing welly boots for the ground was very sticky and even a cursory examination showed that, as I had suspected, the land was boulder clay, sometimes referred to as till.

Boulder clay! Flint pebbles are a giveaway in the soil
adjacent to Kentle Wood, Daventry. 25 February, 2016
There was nothing clever in coming to this conclusion; among the cereal plants the soil was littered with pebbles and shattered lumps of flint. This is a rock not found in Northamptonshire, ergo, somehow these flints had been transported here, perhaps from Norfolk. It was over much of Northamptonshire that the last ice sheets melted at the end of our most recent ice age, and as this melting took place the burden of rock and sand embedded in the ice was dropped.

This moraine also contained 'rock flour' - rocks ground up to a material so fine that, when wet, it took on a thick, sticky consistency - clay. It helps to explain why some of the trees, fifteen years after being planted are not as tall or robust as I feel they might be; these soils, as any half-decent gardener will know, can be cold, lacking air and poorly drained.
Ouch! Motor cyclists have found a way
into Kentle Wood. 25 February, 2016

It is clear that motor cyclists have recently found an entry point into Kentle Wood and their wheels are churning up this clay in a very unsightly manner. At the moment their depredations are having little or no effect on wildlife, but if it goes on...

The cluster of brown buds at the end of a twig makes
oak easy to identify.  Kentle Wood, Daventry.
 25 February, 2016

So, although during yesterday's visit to Stefen Leys there were signs of spring, these cold soils of Kentle Wood are holding things back. Buds were almost breaking in Stefen Leys Pocket Park; in Kentle Wood the oaks, for example, are yet to show any swelling. Incidentally it is the cluster of brown buds at the end of a twig that make an oak easily recognisable.

Once seen, easily remembered. The black
buds of ash. Kentle Wood.
25 February, 2016

As for ash, the soot-black buds are also very distinctive but likewise are not yet showing any the growth that might be occurring on lighter, warmer soils. The upshot of this is that Kentle Wood is still wearing a wintry appearance and it may be weeks before things really get going.

At Badby Woods, only a couple of miles away as the crow flies, things are different. Centuries of falling leaves have been incorporated into the top soil, greatly raising the humus level and there are already encouraging vernal features to be seen. Perhaps that should be my next destination.

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