This is the second column in a series on native shrubs that function in garden ecosystems by providing food, cover, and/or nesting sites for garden wildlife. The first essay in this series, devoted to black chokeberry (Aronia melanocarpa), diervilla (Diervilla lonicera), meadowsweet (Spiraea alba var. latifolia), and wild rose (Rosa virginiana), can be found at http://gardeningintunewithnature.bangordailynews.com/2015/04/07/vegetables/gardening-for-wildness-functional-native-shrubs-support-garden-wildlife/.
The three native shrubs presented below are vital plants in Marjorie’s Garden, particularly in summer, each providing ornamental interest in the form of flowers, fruits, and foliage while supporting the garden’s wildlife.
Summersweet clethra, Clethra alnifolia, is a native plant success story, a favorite shrub among the many gardeners who grow it for its spicy fragrant summer flowers and golden yellow fall foliage. It can be found in the wild in every state along the Atlantic and Gulf coasts and in New York, Pennsylvania, and Tennessee.
Commonly called sweet pepperbush for its peppercorn-like fruit, white alder for the similarity of its foliage to that of the true alders, and “poor man’s soap” because the flowers produce lather when crushed in water, summersweet clethra has been in cultivation for over 200 years. The blossoms, borne in dense narrow spikes, fill
the summer air of the garden with a spicy scent for several weeks in late July and August. Following the bloom are small rounded seed capsules, each one-eighth inch in diameter and containing several seeds, all packed into the same dense spikes of their forebears. These tan-colored capsules persist into autumn, gradually darkening in color and adding textural depth to fall foliage that changes from light yellow to gold to tarnished brass.
While the species has white blossoms, many new cultivars of summersweet have been introduced in recent years, including ‘Hokie Pink’, the cultivar that grows in
Marjorie’s garden. And while the species can reach heights up to ten feet in the garden, newer cultivars selected for compact habits top out at three to four feet.
Summersweet clethra is an essential plant in pollinator gardens, its blossoms attracting butterflies, bees, adult tachinid flies, and hummingbirds. In our garden we have noticed that both monarch butterflies and white admiral butterflies show a preference for the nectar of clethra flowers. Clethra seeds are eaten by birds and mammals, particularly mice.
“In summer, Staghorn Sumac lifts its immense panicles of vivid flowers among the great frond-like pinnate leaves, and in autumn the brilliant fruits and most variously brilliant foliage shout out their color to the dying year. Flaunting orange, war-paint vermilion, buttery yellow, or sometimes angry purple may be seen all together on a single tree. More, it commonly happens that half of a compound leaf, or even half of a leaflet, may retain its rich, deep, shining green, in calm contrast to the flaming autumnal hues. And at all times the lower surface of the foliage keeps its pallid, glaucus cast that, when early frost has brushed it, turns silver. Probably no tree in the country, perhaps in the world, may exhibit so many and such contrasting shades and tints, such frosty coolness with its fire.”
–Donald Culross Peattie, A Natural History of Trees of Eastern and Central North America, 1948
You know this plant, the staghorn sumac (Rhus typhina), its common name derived from the fine felt-like hairs on young stems, giving them the texture of a deer’s antlers. You know it, if only from the window of your car, those roadside colonies of tropical appearance with wine-red pyramidal fruit clusters encircled by long, dark green, pinnately compound leaves. If you are really observant, you’ve noticed that some colonies sport these showy fruit clusters while others lack them. Some colonies are female, some are male.
Actually, each colony can be considered a single multi-trunked shrub, each trunk derived from a suckering shoot that likely originated from a single bird-dispersed seed. The shoot that started it all may have long since died, leaving behind a group of suckers that are all the same sex and that, in time, will produce more suckering shoots. And so the colony grows, old stems dying, a multitude of young suckering shoots taking their place.
Throughout its native range, from the Atlantic coast states west to Mississippi, Tennessee, Missouri, Iowa, Minnesota, South Dakota, and Kansas, old colonies of staghorn sumac can cover an extensive area. I recall a two-acre hayfield divided in half by a colony of 20-foot-tall fruiting branches, a beautiful sight in August when the colony was fruiting, in October when the leaves were turning, and in winter when the persistent fruits were dusted with snow.
Staghorn sumac’s vegetative growth habit makes it a difficult plant to bring into some gardens. When I recommend its use as both a lovely ornamental and a valuable wildlife plant, I’m likely to hear the term “invasive” tossed into the discussion. But no, a native plant, by definition, cannot be considered invasive. Aggressive it is, for sure. In the right place, in the right garden, I like “exuberant”.
It comes down to a matter of placement. The suckering habit of staghorn sumac can be controlled by mowing, paving, and water. For example, I recollect a colony of fruiting plants in Orono, Maine, growing between the banks of the Penobscot River and a paved road, their spread controlled by water on one side, asphalt on the other. In the village of Orono, I lived next door to a colony of sumac in a neighbor’s back yard, its spread limited by the lawn mower.
Staghorn sumac’s shallow, wide-spreading roots make it ideal for soil stabilization along slopes, streams, or pond-side, wherever its suckering habit can be tolerated or controlled and drainage is good. Because of its tolerance of salt, it is also an excellent plant for seashore and roadside plantings.
The berries of staghorn sumac, small fleshy drupes covered with fine red hairs and borne in cone-shaped clusters, are eaten by ruffed grouse, eastern phoebe, common crow, northern mockingbird, gray catbird, American robin, wood thrush, hermit thrush, eastern bluebird, and over 30 other bird species. Because the fruit persists through the winter, it is an excellent emergency source of food for these creatures.
Staghorn sumac’s spring flowers, greenish-yellow and borne in conical clusters, provide nectar for bees and several butterfly species, including banded and striped hairstreaks. It is also a larval host for the luna moth and the spring azure butterfly. In late August, its leaves are riddled with the chewing of these caterpillars.
For those who can manage its exuberance, staghorn sumac belongs in the wildlife garden where it will nourish a host of birds and insects. And it belongs in the ornamental garden where the gardener can watch it change in texture and color through the seasons.
The flowers of common elderberry (Sambucus nigra ssp. canadensis), called “elderblow” by those who turn them into fritters, flower in June in Marjorie’s Garden. Their purple-black berries ripen in the second half of August. White-throated sparrows pluck the berries one at a time, but we cut entire fruiting clusters from the shrubs, take them inside to do the plucking, then fast freeze them on cookie sheets before packing them in freezer boxes.
All winter we have elderberries for muffins, simply substituting them for blueberries in a favorite recipe. They offer a unique crunchy texture to the muffins, and they are not as sweet as blueberries. High in antioxidants, elderberries can also be used to make jams, jellies, pies, and, of course, wine.
If you do not grow common elderberry in your garden, you can harvest berries from plants growing in the wild throughout their native range, the entire U.S. except for the Pacific northwest, Nevada, and Utah. Just remember to tread lightly as you harvest, for the canes are easily broken, and leave plenty of berries for the birds.
Common elderberry is one of the best native shrubs for sustaining the garden’s birds. In addition to white-throated sparrow, over 48 other bird species, including chipping and song sparrows, indigo buntings, northern cardinals, bluebirds, waxwings, thrushes, catbirds, yellow-breasted chats, and rose-breasted grosbeaks, are known to eat the berries as they ripen through the summer. Flycatchers, woodpeckers, wrens, and vireos visit elderberries in bloom to capture insects.
Elderberry flowers are a nectar source for adult butterflies while the hollow stems provide nesting sites for solitary bee species, including mason bees (Osmia sp.) and small carpenter bees (Ceratina sp.).
We grow most of our elderberries in a bed that borders the east side of our house. From the overhanging porch we look down into the canopy of large pinnately-compound leaves raising flat-topped clusters of creamy white flowers to the June sky. And in late August we watch the sparrows feast on the fruits. They perch on slender pithy canes that bend toward Earth, jumping up to pluck the ripe berries.