by Joanne Murray
When I moved to my new house last fall, I was disappointed to find that the main tree visible from the back of the house was a sumac. Sumacs, after all, are weedy little trees that grow along the most desolate, untended roads, on the bits of property left to whatever invasive plants can take root there. They grow in clusters because of their way of cloning themselves into small forests by sending out runners. Yes they are distinctive with their red candles and brilliant fall foliage, but basically I thought of them as weed trees. This one was not just a weedy sumac, it was a possibly dead weedy sumac. The shape of the branches was right, but where were the red fruits? Spring came, the tree leafed out, there were flowers, but still – when all the other sumacs seemed to be making fruits – mine did nothing.
Maybe it’s a bit eccentric to be musing about tree reproduction while driving to the grocery store. It came to me one day in the car that maybe sumacs are dioecious, having male and female flowers on separate trees. Only the girl trees would have the red fruits. Maybe my tree was a boy! Wikipedia confirmed my hunch, all was explained.
Seeing it through my bedroom window as the summer progressed, I grew to appreciate the sumac as an ornamental tree, European gardeners apparently do already. Fine Gardening recommends a cultivar of staghorn sumac (“Tiger Eyes”, with fine fernlike foliage). Native Americans too made a sort of lemonade from the fruit (“rhus juice”!) and smoked sumac mixed with their tobacco. In middle Eastern cuisine, sumac is used as a lemony-flavored spice. What was not to love about my tree? Then I noticed some premature fall color – yellow. But that wasn’t right, sumacs turn a striking crimson. Back to the internet. This time I happened upon a publication of the Delaware Department of Agriculture called “Mistaken Identity? Invasive Plants and their Native Look-Alikes.” There I read that staghorn sumac is easily confused with the alien tree imported from China in the 1700’s – ailanthus, or Tree of Heaven. Both trees have very large leaves compounded of slender leaflets. The diagnosis would be easy: sumac leaflets have saw-toothed edges, ailanthus leaflets have smooth edges with one or two ripples at the base. At the edge of each ripple is found a distinctive small round gland.
Here is the leaflet I collected first thing the next morning –
Yes, Reader, my sumac was an ailanthus, the sumac’s evil twin. Ailanthus, unlike sumac, can make a terrible smell when the bark is injured. Ailanthus, like the black walnut and unlike the sumac, poisons the soil so that other species cannot compete for territory. Ailanthus can grow in hostile urban environments: the tree that grew in Brooklyn was an ailanthus. Nobody makes a refreshing drink from its fruit, nobody smokes it. True, in China it is used to cure baldness and mental illness, and it is fed to silkworms (which is why it was brought to North America in the first place). But in the U.S. it is classified as invasive; googling “ailanthus” leads you to websites advising how to kill it. To many who know it well, ailanthus is the Tree of Hell. Now I can recognize ailanthus everywhere. This time of year the female trees bear huge rosytinged yellow clusters of samaras, or dry winged seeds like maple seeds. Ailanthus is a taller tree and a little more robust; sumac leaves are droopier. I have a few consolations for the loss of my benign native sumac. The ailanthus is actually quite handsome if you can ignore its inner hellishness. Mine is at least a boy, who will not be scattering seeds to sprout all over my little backyard.
And best of all, there has been the Joy of Google. The natural world becomes more interesting as one learns to name what one is looking at. The guide to invasive plants describes nineteen more pairs of look-alikes. Maybe my next projects will be to distinguish invasive porcelainberry from our native grapes and learn about giant hogweed.
Copyright 2013 Joanne L. Murray