AUTUMN FOCUS
A Walk
Woods in the
Our native woodlands offer huge value when it comes to biodiversity, not to mention inspiring wildlife and trees. Richard Nairn takes a walk through Wicklow’s backroads.
I
entered the woodland just after dawn to the sound of a great spotted woodpecker drumming high above in the alder trees. For weeks I had been listening to this iconic sound, but had not managed to see any of these recent colonists to Ireland. Then, suddenly, there was a woodpecker in the tree above my head giving a loud “pik-pik-pik” alarm call. I knew that I must be near the nest, so I hid beneath some foliage and waited. Then the adult bird, in striking black, white and red plumage, landed on a nearby tree with a beak-load of big white grubs, which it promptly delivered to a chick poking its head out of the nest hole. This is a fragment of old native woodland in a river valley that forms one boundary of our family farm in east Wicklow. Because the ground is permanently wet, the tree canopy is dominated by alder but there is plenty of willow, ash, holly, birch, hazel and oak on the drier slopes. As well as regular winter flooding when the river overflows its banks, the ground is also kept damp by the trickling streams that come from groundwater springs on the slopes above.
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Woodpecker at nest nole, credit Richard Nairn
Riparian (or riverside) woodland has huge benefits for biodiversity both on the land and in the water. The roots of the trees intercept nutrients draining off agricultural land in the catchment, trapping these in the woodland soil. Studies in the USA have found that streamside forests are very effective at removing excess nutrients and sediment from surface runoff and shallow groundwater with up to 90% reductions in nitrate concentrations measured in rivers
Irish Wildlife Autumn ‘19
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31/10/2019 13:50
