The other day I was teaching a group about native Illinois trees and of course I was all excited because I was teaching about trees which is my number one passion. I know in the past I've talked about native plants and have of course mentioned my number one favorite tree that just happens to be an Illinois native – Taxodium distichum Baldcypress. So I figured this time around I would focus on some small and medium sized native Illinois trees considering Baldcypress has the potential to reach 50-70 feet tall!
I want to preface this article with something that I feel is very important in regards to trees – and that's the idea of tree diversity. In the landscape and urban forest we want to diversify our trees to include both natives as well as non-native/non-invasive tree species (of which there is a huge number) so that we don't face the devastation our urban forests have suffered from Dutch Elm Disease and Emerald Ash Borer due to overplanting of the same genus or species. With that said – let's take a look at some interesting Illinois native trees.
American Hophornbeam (Osrya virginiana) – This tree is considered one of Illinois' toughest native hardwoods resistant to a variety of insects and diseases. Reaching 30-40 feet, it is a slow grower, growing less than a foot each year but worth the time. It should be noted that American Hophornbeam is very sensitive to salts so avoid areas where salt sprays or salt run off from deicer salts can occur. This tree is better suited to a larger area where it's drooping, horizontal branches have room to show off its beauty. This tree also has another interesting feature – hop-like looking fruits . Plant in part-shade to full sun in well-drained soils in the spring to allow it time to establish in the soil.
Carolina Silverbell (Halesia Carolina) – This is considered a medium sized tree reaching 30-40 feet tall providing white flowers in the spring time and yellow leaf color in the fall but it is known for dropping leaves early. Make sure to plant this tree in the spring to allow time for it to establish in the soil and it will even tolerate some shade but avoid alkaline sites as it can cause iron chlorosis to occur. A slightly acidic part shade site in moist, well-drained soils is the perfect location for Carolina Silverbell.
Downy Serviceberry (Amelanchier arborea) – This tree has a number of different names including Juneberry, Shadbush, and Servicetree. It produces a very tasty fruit, ripening early to mid-summer, for which you must be speedier then the birds to harvest or provide some level of protection (netting) to keep the birds from getting the fruit first. Downy Serviceberry can reach 15-25' tall and can grow either as a multi-trunk or single stem tree that blooms white in the spring with yellow-orange to red fall color. This tree is also tolerant of poorly drained sites and black walnut.
Eastern Redbud (Cercis canadensis) – How can you talk about native Illinois trees and not include the iconic Eastern Redbud? This small tree native understory tree can reach 20-30 feet tall with available cultivars such as The Rising Sun only reaching 12-15 feet tall and provides peachy-tangerine colored leaves throughout the growing season or Forest Pansy with distinctive purple-red colored leaves all season. Both have the traditionally recognized flower color of the common Eastern Redbud but with a few spiced up features – shorter height and interesting leaf color.
River Birch (Betula nigra) – Did you know that River Birch is actually an Illinois native? This trees pushes the boundary of being considered a medium size tree (medium is usually up to about 50') but can range anywhere from 40-70' and there are cultivars available that are much shorter. Fox Valley River Birch (Betula nigra 'Little King') only reaches 8-10 feet tall which is much smaller and more space friendly for small yards. River Birch are prized for their cinnamon colored exfoliating bark – providing wonderful winter interest in the landscape. As is implied in the name River Birch preferred moist well-drained soils – so avoid planting them on high and dry locations such as berms. For fun tree trivia the tallest River Birch on record is 145 feet tall.