Nature Notes

Jenny Dixon

Wharfedale Naturalists Society

wharfedale-nats.org.uk

IN the olden days before the invention of fairy lights and sparkly decorations, people adorned their homes for Christmas with greenery- traditionally swathes of holly, mistletoe and ivy, all evergreen and all with berries, - red, white and shining black. No doubt these plants featured in folklore predating Christianity though they adapted well, particularly the first two – mistletoe with its mystical aura, studded with pearl-like berries and growing out of the leafless boughs of winter trees: holly with its thorny leaves, milk-white flowers and blood-red berries easily fitting into Christian symbolism. However, this year I want to celebrate ivy.

Not a tree like holly, not a parasite like mistletoe, ivy can run over the ground forming a dense mat but what it really likes is to climb – using trees, cliffs or man-made structures to reach up to the light and do its own photosynthesis. It doesn’t take sustenance from trees; its tenacious rootlets don’t penetrate, just attach. When it clothes a whole tree it’s likely the tree was dying or already dead. A healthy tree can control its clinging companion by overshadowing it once Spring comes.

And think of all the plus points. In my garden there is still some colour – hardy winter pansies, shop-bought cyclamen and the dejected remains of African lilies. However, given a sunny day, it’s the ivy on the trellis that is a-buzz with insects. Ivy bears its clusters of yellowy-white flowers well into winter and these are rich in nectar for short-lived flies and late bees and anything else that fancies an energy boost. Then – in the dead of winter- the berries form, providing fruit for the birds long after berberis, cotoneaster, holly and hawthorn are stripped bare.

Consider, too, how the evergreen leaf-coverage provides a hiding place and a sheltered roost on chilly nights for birds. Then – come the Spring – this same foliage will hide the nests of several species of native songbird. Even that now rare migrant the spotted flycatcher loves to nest in creepers and will tolerate lots of human comings and goings in exchange for such a sanctuary.

For me the most intriguing denizen of ivy is the caterpillar of the holly blue butterfly. This pretty butterfly has two broods. Its caterpillars feed on holly in Spring but then in summer, as adults, lay their eggs on ivy which sustains the next generation of caterpillars – and the double cycle continues. So – holly is wonderful, but, for me, ivy “bears the crown!”