Tasty treats in ash trees for woodpeckers

DurhamRegion.com
May 1, 2014
By Margaret Carney

There’s always a silver lining, right? Yes, Durham’s trees have been taking a massive hit recently, hammered by the ice storm, torn up by Hwy. 407, inflicted by a host of blights, cankers and fungi carried in by our global economy. And the latest, greatest scourge: the emerald ash borer, a pretty little insect from east Asia that is greedily destroying our ash trees. Ash trees that make up 30 to 40 per cent of our urban forests, and which spread so easily, freely, generously across the countryside, having pointed seeds designed to drill into the earth as they fall.

But let’s look at the bright side: what’s happening to so many of our trees happens to be fabulous for woodpeckers. And woodpeckers are wonderful for forests, an integral, hugely valuable part of the woodland ecosystem.

Take, for example, their diet of insects and grubs. Downy, hairy and red-bellied woodpeckers have already honed in on the emerald ash borer. They find the larvae so tasty that populations swell in infested areas, taking advantage of this sudden bonanza of small beige grubs under the bark.

Remember, it’s not woodpeckers killing a tree, but the alien pests chewing on it. Once an ash tree is infested, it’s going to die, but if 50 per cent of the grubs attacking it are devoured by woodpeckers, that makes 50 per cent fewer beetles to hatch out and fly off to virgin ash groves. Which they’re doing all over eastern North America, where eight billion trees are at risk. (Mountain ash, of the rose family, is not susceptible, thank goodness.)

The one good thing to come out of the December ice storm: a myriad of tree stubs and snags for woodpeckers to nest in. And the best thing we can do for woodpeckers is leave dead trunks and limbs standing -- in our creek valleys, sure, but even as a natural garden feature in our parks and yards. A neighbour of mine, heartsick when a huge silver poplar had to be taken down for safety reasons, left a monolith of its massive trunk standing, and planted Virginia creeper to cascade over it. I have a 15-foot–tall spruce stub out my sunroom window, a convenient perch for many passing birds.

We humans tend to manicure our surroundings so severely that children grow up thinking dead trees are an eyesore, something to be ‘cleaned up’ instantly. But interesting, gnarled old trees with hollows for owls, flying squirrels and woodpeckers to nest in are treasures, and biologists claim a tree provides more benefit to the web of life after dying than it ever did while alive.

Our forests, urban and rural, are part of our own living ecosystem, and we’re all in it together. Another good thing we can do: plant a tree. Plant lots of trees.