Autumn is my favorite time of year, and during the dog days of late summer I particularly look forward to the cooler, crisper, colorful months to come. That’s why I am delighted when, on some sultry August afternoon, I notice that our Acer rubrum ‘Schlesingeri’ has begun to express the first hints of leaf color at the Arboretum. In most years, the green foliage of this early-coloring red maple shades to bronze by mid August, and by early September the entire canopy is ablaze in carmine red. The colorful display usually holds into October.
The precocious and stunning autumn coloration of this selection first caught the eye of Arboretum director Charles S. Sargent in the late 1800s. The original tree grew at the home of Sargent’s neighbor, Mr. Barthold Schlesinger, in Brookline, Massachusetts. On February 13, 1888, budwood from this tree arrived at the Arboretum and, upon grafting, became accession 3256-A. It was planted along Meadow Road across from the Hunnewell Building, where it remains to this day.
Curiously, this cultivar’s introduction to the ornamental scene occurred not in North America but in Europe. Sargent had shared it with the world-famous Späth Nursery in Berlin, which first made it commercially available in their 1896–1897 catalog. During World War II, the nursery dissolved, no doubt limiting the supply of this sought-after clone. In 1951, the Arboretum distributed plants to some 25 cooperating nurseries as a means of promoting the cultivar and increasing supply. In his description of the tree and this distribution program, Donald Wyman (1956) noted the efforts made to learn if the precocious fall color trait was truly genotypic or just a function of environment: “…scions from this variety were grafted on seedling red maples, but both the scion and the understock were allowed to grow. In the fall, it was clearly evident that the variety schlesingeri [‘Schlesingeri’] would produce autumn color several weeks before the seedling understock on which it was growing, regardless of where it was planted.”
Unfortunately this cultivar is now often misidentified, so the Acer rubrum ‘Schlesingeri’ that you purchase at the local nursery may not be true-to-type. This has even happened at the Arboretum. In the early 1980s, three trees labeled as ‘Schlesingeri’ were donated by a large, reputable, national nursery. But in 1989, Arboretum horticulturist Gary Koller noted that they “do not match 3256-A …identification (of) this cultivar is questionable.” Further observations proved Koller correct and these trees were duly removed. Michael Dirr, in his Manual of Woody Landscape Plants, also noted that “some of the material in today’s market does not appear similar to the Arnold Arboretum’s fine specimen.” And an interesting study on red maple cultivar coloration (Sibley et al. 1995) yields further evidence: although the trees of ‘Schlesingeri’ examined in the study were obtained from a reputable nursery, they developed the wrong leaf color (orange) far too late (no earlier than the 5th of October) to be true ‘Schlesingeri’.
Over 120 years later, this old sentry remains in its original location. It stands 65 feet (19.8 meters) tall with a crown spread of about 60 feet (18.3 meters), and its trunk diameter (below the lowest branch) is 44.6 inches (113.3 centimeters). Red maples generally reach maturity at around 75 years of age, so it is no surprise that this individual is in decline. Recent efforts to maintain this important lineage by rooting cuttings have been a success: accession 408-91-A grows next to Faxon Pond, and scores of new cuttings are now rooting in the greenhouse. One of these new plants will eventually replace the original tree, while others will be distributed to commercial nurseries so that they, too, will have the real cultivar again.
Sibley, J. L., D. J. Eakes, C. H. Gilliam, G. J. Keever, and W. A. Dozier Jr. 1995. Growth and fall color of red maple selections in the Southeastern United States. Journal of Environmental Horticulture 13(1): 51–53.
Wyman, D. 1956. New and rare ornamental plants recently distributed by the Arnold Arboretum. Arnoldia 16(7–9): 33–51.
Michael S. Dosmann is Curator of Living Collections at the Arnold Arboretum.