Aglove of ivy grasps the lower trunk of a mature silver birch. It’s long a thing of parasitic charm, this stuff – English ivy on trees, houses, walls. It’s bad, isn’t it? Weakens brickwork, cancers bark, kills trees. Get rid of it, they say. But it’s so pretty, you say.
Ivy’s life cycle is vividly imagined. Juvenile, it grows in woodland and hedgerow in a sort of slink along the ground until it finds a tree trunk, or whatever else. On touching the tree, its roots change shape to fit the surface, then secrete a glue-like ooze to attach. Root hairs emerge, find gaps, slide in, then kink to lock, like a climber attaching gear into a rock face. If it’s on your house, by the time you pull it off the wall the damage is done.
But ivy wasn’t always a pariah, more a blessing. It protected houses from demons at times when spirits were close, like Christmas and All Hallows. Milk drunk from ivy wood cups were said to cure whooping cough.
I notice the trunk beneath this ivy is darkened, as if ink-dipped. Above, it is silvered only in patches. But the tree looks strong. I part the arrowhead leaves. Cobwebs bridge delicate spans, caught with debris. Here are generations: grey cables of branch wired into the trunk alongside more verdant brown, some of it hung with rows of desiccated roots like millipede legs. Deeper: knots are thick with cobwebs. A few late-season, cold-slowed wood ants loitering around another. It’s dense, microscopically, but clearly a layered shelter for insects. Insects bring birds. In autumn it flowers. More birds. More life. This isn’t just a plant, it’s a habitat.
But what of this tree? Autumn’s here, winter coming. The canopy will thin, sun will find the ivy and it will grow. But it won’t kill. Ivy doesn’t strangle, nor does it pull nutrients from the bark. It might weaken a feeble tree, or compete for meagre nutrients at ground level. But the tree supports the ivy, just as it’s meant to.
And it is pretty. It’s a windy day and the ivy catches it, sending the whole frantically aplay. And just for a second, if you let yourself see it, the tree shivers.