Plant friends and foes

Maple Trees,
Norway and Others

Terry Bonace

As a child in Ohio, we had a large Norway maple in the back yard. It was an excellent climbing tree and I have wonderful memories of scaling it to its tallest branches. Of course, we had no idea what species of maple it was. We simply called it “the maple tree.” It wasn’t until I went off to college and took a class on trees that I was able to identify it. So I have a sentimental attachment to Norway maples.

I also have a large Norway maple tree (that I did not plant) in my yard in Beverly Shores. For that one I feel less warmth and more of a quandary. Do I take it down when cutting down trees is almost anathema to me (not to mention expensive)? Why would anyone cut down a large, handsome tree? It turns out that Norway maples have become an invasive plant and in some areas are taking the place of native maples. Their little whirligig fruits (called a “double samara” by botanists) can travel large distances in the wind, are produced prolifically, and germinate readily in any space. If you have ever weeded where a large Norway maple is nearby, you will know just how well the seeds germinate. Norway maples tolerate shade well and can persist as a sapling in heavy shade for many years waiting for an opening when a tree falls or dies to give it the sunlight it needs to grow into a mature tree. Norway maple is a problem in many parks and natural areas including our own National Lakeshore. It is especially invasive in the Glenwood Dunes area, where it originated from old home sites.

Norway Maple in Autumn

Norway maple has a much longer history in the United States than many other non-native species. The tree was introduced in the United States in 1756. George Washington purchased two trees for Mount Vernon in 1772. Norway maples probably had their biggest expansion in the United States when Dutch elm disease struck in the mid-20th century and decimated one of our most beloved trees, the American elm. Norway maple was widely planted as a replacement. Norway maples do very well in urban settings, tolerate pollution and road salt, and are fairly pest resistant. So perhaps it is understandable why in cities the tree is still quite popular. But here in Beverly Shores, where road salt and urban pollution are not a problem, there is little excuse for them.

Beverly Shores is blessed with many native maple trees. Most are red maples, a beautiful tree that is tolerant of very wet soil and will grow quite naturally in a bog, but also tolerates dryer soils quite well. See them growing along Broadway in Beverly Shores. Sugar maples also occur here. Think of maple syrup at Chelburg Farm. There is also box elder, a maple that does not quite look like a maple because it has compound leaves. Sometimes it has 5 leaflets and sometimes it has only three. When it has only three, it can appear to the novice to be poison ivy (but poison ivy leaves occur alternately on the stem while box elder leaves occur in pairs on the stem). There are several small box elders growing along the steps going down to the beach at Reborra Plaza. Box elders don’t obtain the heights of our other maples, are considered weedy trees and are not planted as ornamentals. Silver maple is another native tree. It is common and very fast growing and sometimes achieves an attractive vase shape. It also is quite tolerant of wet soils. But its branches break easily, making it susceptible to storm damage, and its shallow roots can damage your sidewalks and driveways. While I have not observed black maple, it is known to grow in the area. It is said to grow in rich, moist woods, to also be used to be used for syrup, and is considered by some botanists to be a variety of sugar maple, which it closely resembles.

Norway Maple Double Samara

How do you know if you have a Norway maple? There are lots of unique features like its habit of lea ng out early and the lack of a brilliant fall color. Even the angle between the double samara fruit is characteristic. But the easiest, most diagnostic identification technique is to pluck a leaf from the tree and see if there is white sap on the stem. If so, it is certainly a Norway maple. Now, as to what to do with it is another quandary altogether.

You can do what I do and prevent its spread by weeding all of the Norway maple saplings. This is not too hard in my yard where dry sand prevails but if you have moist woods nearby, it will be a greater challenge.

Red Maple

If you are considering planting a maple tree, please don’t plant a Norway maple. The red maple in full fall color is beautiful, looking as if it might burst into flame, as it turns a glorious orange-red. (This is the tree that provides the dazzling fall colors attracting “leaf peepers” from across the world in the northeastern United States). Red maples tolerate both our dryer and wetter areas in Beverly Shores. Sugar maple is a close second in fall color. Norway maple, however, gradually turns a dull yellow and never gives any suggestion of a trace of orange or red. (Even the variety of Norway maple called “Crimson King,” though featuring leaves of a deep purple to red all year long, simply turns brown in the fall.) All of our native maples have evolved here as food and shelter for our native birds, mammals, insects, and other creatures. Make a home for them too.

The Environmental Restoration Group (ERG) will be glad to help identify plants for you and make suggestions for removal and for native replacements. Don’t hesitate to contact Terry Bonace (tbonace@gmail.com), Candice Smith (cmsmith2@umail.iu.edu), or Bill Schaudt (blschaudt2@gmail.com) for assistance.

Beverly Shores Environmental Restoration Group,
P.O. Box 667, Beverly Shores, IN 46301