Red maple provides brilliant fall foliage in our woodlands and cultivated landscapes. Acer rubrum is the fourth most common tree in the natural areas of The Holden Arboretum, trailing Acer saccharum (sugar maple), Fagus grandifolia (American beech), and Liriodendron tulipifera (tuliptree). It is native from southern Ontario to Newfoundland, south to eastern Texas and just north of Miami, Fla.
One of our more impressive red maples is in the Sugarbush woods, west of Sperry Road, and south of the stream, on a rise just east of the wetland. It has a height of about 90 feet, a spread of about 44 feet and a diameter at breast height (DBH) of over 40 inches. Its age is hard to guess, but it is most likely more than 100 years old given its large trunk and its bark that has shed the shaggy strips that are common on mature red maples.
Of the 112 red maples planted in Holden’s gardens and fields, 77 remain (19 died and 16 were removed). There are currently 20 cultivars (cultivated varieties) of Acer rubrum in our plant collection including 10 individuals of ‘Red Sunset’. Acer rubrum ‘Red Sunset’ was highly recommended by the Ohio Nursery and Landscape Association’s Plant Selection Committee in 1982. Our specimens average 40 feet in height after 40 years and reward us each October with foliage that simply glows. I noticed a specimen last fall on the south side of Willoughby Fine Arts parking lot that was a prime example of why this cultivar is still the best selling red maple and perhaps even the best selling tree in the country.
Another worthy red maple cultivar at Holden is ‘October Glory’. Its fall foliage is a deeper red than ‘Red Sunset,’ and it has on average wider branch angles that may prove to be stronger than those of ‘Red Sunset’. One Acer rubrum ‘October Glory’ is located along the exit drive of the parking area. There the soil is usually fairly dry in late summer and as a result the tree turns color anytime between late August and late September and is usually defoliated in mid-October. In contrast an ‘October Glory’ planted in the wet meadow south of the Arborvitae Collection has turned color between late September and early October, and is usually defoliated by early to mid November.
The flowers of red maple appear in March-April and color the tree a subtle reddish haze. Trees are either male or female. By mid to late May seeds are ripe and ready to be carried off by the wind. Seed crops can be so heavy some years on female trees that not much foliage is produced until June. There are a number of naturally occurring hybrids of red maple with silver maple. These Freeman maples, Acer x freemanii (A. rubrum x A. saccharinum) tend to be faster growing than red maples. Some selections have been made that combine the best qualities of both parents. Acer x freemanii ‘Autumn Blaze’ grows over 2’ per year and has red fall foliage in October, sometimes starting in late September and ending in early November. One ‘Autumn Blaze’ planted in the Specimen Tree Collection as a balled and burlapped tree, with a trunk measuring 2 inches in diameter 6 inches above the ground in 1990 measured 53’ x 40’ in October 2009.