Illustration by Adelaide Tyrol
Michael Dirr, my favorite horticulturalist, is a man of strongly held views. Though our tastes don’t always align (one of my favorite plants, Kolkwitzia, “gives him a headache”), we share a similar fondness for viburnums. “A garden without a viburnum,” Dirr writes, “is akin to life without music or art.” I wouldn’t go that far, but there is something admirable about every viburnum that I can think of.
It’s not difficult to recognize a member of the genus Viburnum, and the six or so viburnum species common in the Northeast are fairly easy to identify – an endearing trait, for sure. All of them are shrubs, with opposite leaves (overall, opposite leaves are unusual in woody plants), and they all have five-petalled whitish flowers in flat-topped or dome-shaped clusters.
Once you have pegged a shrub as a viburnum, some of their names are, for once, quite helpful in telling one from another: maple-leaved viburnum has maple-like leaves; highbush cranberry has bright red cranberry-like fruits, and the low, rooted stems of hobblebush appear to be designed both to hobble your horse and trip up anyone else who attempts to penetrate a hobblebush stronghold.
They choose different habitats as well: hobblebush favoring moist, shady understories and maple-leaved viburnums drier soils. The best place for highbush cranberry and nannyberry is where there is both water and a good measure of sunshine. The edges of brooks are perfect, especially for nannyberry.
I pass a large clump of nannyberry along a brook near our house almost every day and faithfully pause to give it a nod of appreciation. It has dark, shining leaves with tiny, evenly-spaced teeth at the margins. The elliptical, opposite leaves line up neatly, each one with a straight, tidy central vein. When there are leaves on nannyberry, you can clear up any doubt you might have as to its identity by looking closely at the petioles: they are slightly winged and the wings are wavy and irregular, unlike those of any other shrub.
Various parts of nannyberry – the fruits, the bruised twigs, and the wood – are said to smell like sheep. Some people go farther and say the wood smells like a wet goat, a hypothesis you can test yourself by sawing off a nannyberry branch, mashing it with a hammer, and sniffing the battered plant part. My own conclusion is that nannyberry does smell very faintly – and pleasantly – of sheep, but not at all like a wet goat.
Although the foliage is tidy, the shrub as a whole is not. Among the largest of the viburnums, sometimes reaching 20 feet tall, nannyberry lacks structure, and its long stems often bend this way and that.
In May, the creamy white flowers are abundant. Though each one is tiny, they are borne in showy clusters, three or four inches across, and are pollinated by insects. The fruits are green at first, then yellow, red, and, finally, bluish-black. The blue-black contrasts nicely with bright red fruit stalks. The fruits, too, are said to be ill-smelling, but I have not noticed this. Native Americans ate them fresh and dried and they are recommended for jams and jellies. I’ve given them a try and found them to be tasteless. A person would have to be pretty hungry to eat more than a few. Chipmunks, red squirrels, and many birds eat nannyberry fruits, along with those of the other viburnums, but because they all are relatively low in fat, they are not a real fall favorite.
In autumn, the leaves turn a variety of colors: yellow, deep maroon, and red.
In winter, the buds are long, narrow, and gray; buds that will produce flowers in the spring have a prominent round bulge at the base.
Nannyberry is found on moist soils in all but the coldest parts of New England, and its range extends west to the Dakotas and south in the mountains to West Virginia.
In 1947, a Eurasian insect, the viburnum leaf beetle, was discovered in Ontario. It hopped the border and was first seen in New York State in 1996. Since that time it has made great strides in a southerly direction. All our native viburnums are potential victims and highbush cranberry is especially susceptible. Both the adults and the larvae feed on viburnum leaves and the results can be deadly.
If streambanks were to lose their nannyberries or highbush cranberries, dry woods their maple-leaved viburnums, or mossy woods their hobblebush, the landscape would not be the same. Both Michael Dirr and I will be extremely upset, and I’m sure we won’t be alone.