We are rapidly approaching the fall foliage season when deciduous trees will begin to display spectacular colors from bright
yellow to orange to red. I'm hoping that the fall color will be intense and long-lasting this season. Maples, both native
and non-native, contribute a wide range of colors to the fall spectrum.
Even during the rest of the year, maples contribute greatly to the beauty of the landscape. Our native red
(Acer rubrum) and silver (Acer saccharinum) maples and their cultivars and hybrids make up the bulk of the
maple shade trees offered in the nursery trade. Both are fast growing, tolerate a wide range of growing conditions and
offer good fall color with the red maples being predominantly red and orange while the silver maple is yellow.
Silver Maple
Red Maple
Of course the red and silver maples aren't the only native maples to be found in Georgia. Lesser known native maples include
the southern sugar maple (Acer barbatum), chalk maple (Acer leucoderme), the mountain maple (Acer spicatum) and the boxelder maple (Acer negundo) with its poison ivy-like leaves as well as several others.
Mountain Maple
Boxelder Maple
The landscape value of some of our lesser known maples is too often overlooked. While the mountain maple and its similar cousin the
striped maple (Acer pensylvanicum) really only grow well in the north Georgia mountains, the chalk maple and southern
sugar maple are drought and heat tolerant smaller trees (20-30 feet) better suited to landscapes where the
red and silver maples may be too large.
Japanese Maples (Acer palmatum)
Despite the fact that I'm known for my eager promotion of native plants, I must profess a real love for Japanese maples. There are
so many different cultivars that I would never attempt a thorough discussion of them all. One group that
really attracts my attention is the threadleaf or dissectum variety (Acer palmatum var. dissectum)
of which there are literally dozens of cultivars. These Japanese maples are noted for their finely dissected fern-like leaves and
come in a variety of colors from green to orange to red. They tend to be shorter, fatter and possess a weeping habit which
makes them attractive even in the winter.
Red Dissectum Japanese Maple
Green Dissectum Japanese Maple
The Japanese Maples available in this country are much smaller than our native red and silver maples which are mostly used as shade
trees. The smaller stature of Japanese maples makes them suitable for small gardens, as focal points or even in containers.
Siting and Planting Maples
Fall is the best time to plant trees and shrubs. The soil is still warm enough to allow for some root growth yet the air
temperatures are cooler and thus less stressful to new plants. I recommend the planting of trees and shrubs between
the middle of September and the middle of February. Planting trees and shrubs as we get to spring doesn't give the plants
enough time to settle into their new location before the heat of summer hits them.
When choosing trees, I tend to stay away from those that are balled in burlap. Sometimes these trees suffer root damage and
have the trunk flare covered with too much dirt when they are dug and wrapped. Container grown trees usually do not have
these problems. Examine the tree before purchase to make sure it has healthy roots, isn't pot-bound and
that the trunk doesn't have any cracks (a problem with some maples that have been laid on their sides in the sun).
If you are planting one of the larger shade maples (red or silver), there are some things you need to remember. These trees
can grow large (50-60 feet tall and wide), they cast dense shade and have shallow roots that can extend beyond the branches.
If planted too closely (within 30-40 feet) to driveways and foundations, their roots can become a problem. Therefore make sure
these trees have ample branch and root room to grow. On the other hand, Japanese maples do not seem to exhibit these surface
root problems. Also unlike their American cousins, Japanese maples usually do better if planted where they are protected from
the hot afternoon sun. This especially applies to the dissectum cultivars.
Always dig a wide hole for your trees. The best planting practices are
to loosen (and perhaps lightly amend) an area that is 10 times the diameter
of the root ball. Your planting hole within this area should be a minimum
of 3 times the size of the root ball. Do not add soil amendments directly
to the planting hole. This discourages the roots from growing out into
the surrounding native soil. Always plant the tree at or a little higher
than the depth at which it's growing. The flare that occurs where the trunk
meets the roots should be visible. The soil needs to be loose, high in
organic matter and well-drained although red maples can tolerate slowly
draining soil. Apply and maintain a 2-3 inch layer of organic mulch over
the root zone. Water the trees deeply once a week when allowed by the current
watering restrictions. During the growing season, I recommend 15 gallons
of water per week per inch of trunk diameter (measured at ~4 feet from
the ground). An inch of water or rain over the entire area will achieve
the same results. Once established, maples are pretty drought resistant.
Non-Native Invasive Maples
Unfortunately, we have several species of non-native maples that have become a problem. The
Norway Maple (Acer platanoides) which doesn't tolerate the heat in most of Georgia is an extremely invasive
pest plant in the Appalachians from northern Georgia to Maine, in the upper
midwest and Pacific northwest. It is rapidly outcompeting other native
trees. The Chinese amur maple (Acer ginnala) and the European sycamore maple (Acer pseudoplatanus) are also showing
invasive behavior.
Because we have plenty of native maples and the well-behaved Japanese species,
I think it best to not use the invasive maples listed above.
