Mature concolor fir (Abies concolor) in Council Past President Andy Hillman’s yard. Photo by Andy Hillman

Concolor Fir (Abies concolor)

By Jean Zimmerman, Council Board Member and Commercial Arborist for SavATree

Some might see the concolor fir or white fir (Abies concolor) only as the perfect holiday tree. The soft silvery needles, the graceful form, and perhaps more than anything its scent, redolent of tangerines—all create a specimen that begs to be set up in a corner of the living room, bestrewn with decorations, with gaily wrapped gifts underneath. We’ve had one for many years during the holidays and it always brings pleasure.

At the cut-your-own tree farm we patronize, the saw-bearing hordes descend upon the generous grove of concolors, and a tree-toting worker told me it is in popularity second only to the fraser fir (A. fraseri). President of the New York State Urban Forestry Council Karen Emmerich of Emmerich Tree Farm said, “We sold a lot of concolors last holiday season, and they have grown in popularity over the years. More and more growers are planting them. They don’t have the disease issues that blue spruces have, and they have that lovely bluish tint to their needles. The upper branches don’t shade the lower branches (causing them to develop that scraggly look) like the spruces. My husband Kurt calls them ‘ugly ducklings,’ because when they are young they are kind of goofy looking, but after five or six years they really start to look great.”

Now take a look beyond the holiday season. Concolor is a fir that can be enjoyed on your property spring, summer, and fall as well as when snow sparkles on the ground. In 1953, naturalist Donald Peattie recognized the beauty and adaptability of the concolor and predicted that its future “lies in its value as an ornamental.” Its conical shape, blueish silver color and ability to thrive even on harsh sites has made the tree a favorite for urban landscaping. Full sun is best for this tree, meaning it prefers a minimum of four hours of direct, unfiltered sunlight each day, but it can also do well in part shade. The tree’s preferred pH range is acidic to neutral on moist, well drained, loamy soils, and its hardiness range is Zone 3 to 7.

Young concolor firs managed for Christmas tree use. Photo by Jean Zimmerman

From the branches grow soft needles with whitish lines of stomata on upper and lower surfaces, approximately 1.5 to 3 inches (4 to 8 cm) long, extending from all sides of the twig, and usually blunt-tipped. Cones of 3 to 6 inches (8 to 15 cm) length sit upright on its branches. They start out olive green, turning purplish and then brown at maturity, after which they disintegrate while on the tree. The bark when concolor is young is a smooth gray, thickening with age into rough irregular furrows. Some branches can curve toward the ground while the top branches reach upward.

Its name is as simple as the tree is beautiful. Abies is the Latin for fir trees, and concolor means “together, or of one color.” As Dirr writes in his Encyclopedia of Trees & Shrubs, concolor fir is “one of the most adaptable and beautiful firs for landscape work, particularly in the Northeast and Midwest.” The white fir grows in a spire shape to a height of 30 to 50 feet (9 to 15 m) and a spread of about 20 feet (6 m) at maturity, though in the wild it can reach 150 feet (46 m). Its nicely tiered branches give it a handsome aspect, and it makes a tolerable windbreak.

Abies concolor foliage and buds. Photo by Andy Hillman

As a tree not employed for its lumber, concolor fir has remained naturally protected over the years and offers great wildlife value. Fir trees support grouse, which enjoy the buds and needles; squirrels, rodents, chickadees, crossbills, and Clark’s nutcrackers consume concolor’s seeds; deer browse on its buds, seedlings, and needles; and porcupines are known to gnaw on the bark. ?