In the nursery and landscape industry, saying the words “Red Maple” can apply to several distinctly different tree species and the many cultivars developed from these species. The average homeowner can get confused reading the labels tied to the trees at a nursery or garden centre. He just wants a red maple tree that will improve his property’s curb appeal and have attractive fall colours.
“Red Maples” fall into two basic groups. The first grouping is Native Maples consisting of Red Maple and Freeman’s Maple, a lesser known native maple that grows in parts of southern Ontario. Both species have green leaves throughout the summer months and attractive fall foliage with colours ranging from yellows to orange-red and red. The second group is a collection of “red-leaved” cultivars of the non-native Norway maple that have showy burgundy to reddish-purple leaves all summer long. Their fall colour is unimpressive. These groups are distinctly different.
Native Red maple (Acer rubrum)
True red maples (Acer rubrum) are impressive shade trees that grow to a height of 16 metres with a spread of 15 meters. Some get much larger. Red maple gets its name from the clusters of small, red buds and flowers that appear on the tree in early spring. The flowers become reddish-green winged fruits (samaras) by early-May. The fruit matures in mid to late-May and is used as a food source by some wildlife.
Mid-summer is the easiest time to tell native red maples from the “red-leaved” non-native maples many people mistakenly think are “red maples”. The leaves of red maples have a blush of red when they start to open in the spring, are green all summer long and turn to shades of yellow, orange and red (sometimes on the same tree), lasting for several weeks in the fall. Red maples are amongst the earliest trees to show colour changes in the fall. In nature, red maple trees vary greatly in fall colouration and intensity.
The nursery industry has developed many Acer rubrum cultivars (Trade names), each with its own distinguishing characteristics of form, growth rate, adaptability to habitat, hardiness and fall leaf colour. Cultivars of red maple are more consistently fall coloured than naturally occurring trees.
Click images below for more information on Native Red Maple trees [or download PDF].
Native Freeman’s maple (Acer freemanii)
Freeman’s Maple is a lesser known native maple species found growing naturally in parts of southern Ontario and the Lake States. It is a naturally occurring hybrid of two native maple parents – red maple (Acer rubrum) and silver maple (Acer saccharinum). The hybridization takes the best qualities of both parents – the solid structure, attractive form and showy fall colours of red maple and the adaptability and faster growth from the silver maple.
Acer x freemanii prefers moist, acidic soils with good drainage and is more tolerant of high pH soils than native red maple. It is less susceptible to chlorosis symptoms than either red or silver maples. Their green summer leaves change to yellows and red-orange hues in the fall, varying from tree to tree.
Freeman’s Maple is produced as Acer x freemanii cultivars by the nursery industry. Cultivars are grown from cuttings or by grafting (not from seed), producing near identical offspring of the parent tree. They are given Trade names, some have been patented – like Jeffersred Maple, more commonly called Autumn Blaze Maple. Their consistent form, faster growth rate and brilliant orange-red fall colours have made cultivars of Freeman’s Maple popular in the urban landscape.
Every Autumn Blaze Maple will look very much like the parent it originated from, whereas Native Freeman’s Maple trees grown from seedlings planted into nursery fields will have the varying morphological characteristics common to the species.
Click images below for more information on Native Freeman’s Maple trees or [or download PDF].
Non-Native Norway Maple and its “Red-Leaved” Cultivars
In the nursery world, many “other Maples” display vivid burgundy, maroon and reddish-purple leaves all summer long. They are called “red-leaved” maples. The most popular variety being “Crimson King” maple, which is not a red maple at all. It is a cultivar of Norway Maple (Acer plantanoides), a European tree that has leaves that look similar to native sugar maple. Crimson King maple was introduced in the US in 1947 as a seedling of A. plantanoides ‘Shwedleri” nigrum.
The brightly coloured leaves begin to unfurl shortly after clusters of yellow flowers appear in spring. The flowers become reddish-purple samaras with horizontally spreading wings by late summer. Crimson King Maples have a dense maroon red foliage all summer. The fall colour is a dull brownish-yellow.
It has a moderate growth rate. Height to 12 meters with a spread of 10 meters.
The seed has a low germinative capacity causing many to consider Crimson King as a potentially less invasive species than its parent – Norway maple.
Click images below for more information on non-native “red-leaved” cultivars of Norway maple [or download PDF].
The “Royal Red” Maple is a more recent cultivar of Norway maple. It is rumoured to be slightly smaller at maturity, a bit faster growing and hardier than the closely related Crimson King. It also has slightly better colour than Crimson King with glossy deep maroon foliage all summer long turning reddish-bronze in the fall. Both varieties provide dense shade, have a straight trunk and a well shaped canopy.
Many other red-leaved Norway maple cultivars are available from your local nursery or garden centre, each with its own landscape potential. They vary in form, growth rate, mature size and seasonal colour characteristics.
Native Red and Freeman’s Maple qualify for Rebate consideration when planted under the provisions of the Maple Leaves Forever “Thank You Rebate” program.
Cultivars developed from Native Maples, non-native maples and their cultivars are not eligible for Rebate consideration.
Compiled and written by Carl Mansfield, Arboreal Consultant, Maple Leaves Forever
Editing and layout by Mary Bella, Webmaster & Communications, Maple Leaves Forever