The arborvitae Thuja occidentalis, a tree called cedar in Maine, can live for 300 years and lift its horizontal branches 60 feet or more into the sky. Its roots are anchored firmly in Maine’s past.
In “The Maine Woods,” Thoreau described how Native Americans constructed a carrying harness for canoes from cedar shingles and bark. The frames of the canoes were also made from arborvitae wood and for the same reason that all the old lumber camps of the North Woods had cedar shingles: The wood resists decay forever.
Arborvitae means “tree of life,” a name conferred by the king of France when cedar tea, a drink made by Native Americans from the bark and needles of the tree, cured Jacques Cartier’s sailors of scurvy during their voyage up the St. Lawrence in 1535-36. Arborvitae thus became the first of North American conifers to be cultivated in Europe, introduced to Paris by Cartier on his return.
Never as tall as its neighboring conifers, arborvitae is a compact tree with a buttressed trunk and shredding reddish or silver-gray bark. The soft yellow-green foliage, apple-scented when crushed, consists of tiny, scaly leaves borne in flat, filigree sprays that are a favorite of florists. In late summer the sprays of foliage bear clusters of oval, pea-sized cones that slowly ripen from green to warm brown.
Seedlings may persist for decades in the shade of taller trees, waiting for a gap in the canopy. Those trees growing on rocky upland sites remain small, growing as natural bonsai forms with twisted trunks and gnarly crowns.
Horticulturists have discovered and propagated more than 200 forms of arborvitae varying in foliage color, growth habit, and growth rate. Among the tree-sized cultivars are two selections, ‘Nigra’ and ‘Techny Mission,’ grown for their dark green winter color, an improvement over the bronzy winter color of the species.
The slow-growing forms of arborvitae, often called dwarf varieties, are ideal for small gardens or narrow niches within large gardens. Among the narrow columnar forms is ‘Degroot’s Spire,’ a seedling selection that grows only 6 to 10 inches per year to a height of 8 feet in 10 years. It combines a columnar form with thick, ruffled, medium green foliage and branchlets that occasionally twist and layer over one another. Use it as a single exclamation point, in a grouping, or line up for tall screening in tight spaces.
Commonly known as Emerald arborvitae, ‘Smaragd’ has a narrow, uniform habit and glossy, green foliage in summer and winter. Its growth rate and ultimate size is similar to ‘Degroot’s Spire.’
‘Miky’ is shorter and stouter — shaped more like a teardrop than a column — but with the same narrow, uniform habit and growth rate of ‘Smaragd.’ Single, grouped or lined up to make a compact hedge, ‘Miky’ stays small with little or no pruning. Foliage changes from pleasant green in summer to red brown in winter.
‘Pendula’ is an elegant weeping form with soft, green, lacy foliage that drapes gracefully from attractive, sweeping branches. It grows 6 to 10 inches per year to a height of 8 feet in 10 years.
Among the truly small rounded forms is my favorite, ‘Golden Tuffet,’ a pillow-shaped plant reminiscent of a mushroom cap. It grows only 1 to 3 inches per year to an ultimate height of 3 feet. Its year-round, golden-orange foliage provides striking contrast to the dark green of interplanted creeping junipers.
There are many other cultivars of our native arborvitae and interested gardeners should visit local garden centers to see what is immediately available. A Google image search will expand the list of possibilities. Perhaps your favorite garden center will place a special order.
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