If you drive near rivers in Indiana, you may have noticed a lot of the same types of trees that tend to line the banks of these waterways. After coming up with my own “top 5” list, I also consulted with Lenny Farlee, Purdue forester. Our discussion reached an unofficial consensus on the river trees you are most likely to encounter in Indiana. Of course, other trees are likely to be present, but I’ll explore these five today and ask the question, “If they grow naturally next to a river, would they be suitable for a wet area in my landscape?”
American sycamore – Even if you don’t know much about trees, I bet you could pick this one out from the bark. Sycamore has mottled bark in a sort of army camouflage pattern that is frequently flaking off. The tree grows tall and thrives near rivers. There is a line of Sycamores near Deer Creek, IN, called “Sycamore Row.” Sycamores corduroyed a swampy section of Michigan Road in the 1830s, the first state road in Indiana (Madison to Michigan City). New trees sprouted from freshly cut logs on either end and grew on both sides of the trail, and this is now recognized as a historical landmark. As a landscape tree, it’s a messy tree with large leaves that can smother grass in the fall if not raked or “mowed,” and it is prone to a disease called anthracnose. However, it would do well in or near a wet landscape area.
River birch – As a medium-sized tree, this tree grows near rivers and streams. (It’s a giveaway when “river” is part of the name). It has naturally flaky bark that creates an additional feature as a landscape tree. The tree frequently has multiple trunks growing in a clump. The tree will thrive in a wet landscape area, and I have observed it tolerating some drier locations in landscapes.
Eastern cottonwood – This is another tree found near rivers and trees that can grow quite tall. Leaves are triangular with coarse teeth. One of the biggest downfalls of Cottonwood as a landscape tree is that its fruiting structures contain numerous seeds with cottony hairs attached. When they fall, it literally looks like wads of cotton falling from the tree, which can be somewhat messy in a landscape. However, like Sycamore, this tall tree will thrive in wet habitats.
Silver maple – This tree is frequently found along rivers with other trees in my “top 5.” It is also found in wetter areas of home landscapes, but I have observed it tolerating drier locations. It tends to lose limbs after storms, has shallow roots, produces large “helicopter” seeds (winged samaras that spin to the ground), and presents problems as a street tree. If it is in a remote wet area far from the house, it may be okay. One feature of silver maple is that as the leaves flutter in the wind, they display their silvery leaf undersides. They are easy to grow, but better maple choices for home landscapes are Sugar maple, Black maple, and Red maple. Of these, Red maple is best adapted to the wetter areas.
Boxelder - This tree tends to be less common in very wet areas, but Farlee noted that it is often found near waterways. It belongs to the maple family, and another name for it is the ash-leaf or ash-leaved maple, which refers to its compound leaves. As a landscape tree, it can grow in wet locations, but a downside is that it attracts boxelder bugs, which can enter homes for the winter, similar to lady beetles and stink bugs. Having personally dealt with these insects, I’m ready to cut down my Boxelder.
Although this is not an all-inclusive list, other trees adapted to wet areas include: Baldcypress, Black ash, Pumpkin ash, Swamp cottonwood, Swamp white oak, Honey locust, Bur oak, Swamp chestnut oak, Red maple, Tamarack, and Black willow. You’ll notice again that for some of these species, the name gives you a strong clue as to their habitat preference.
When selecting landscape trees, it is essential to research the tree species to ensure you plant the right tree in the right location. Every tree will likely have pros and cons to consider.