By Lisa Biehle Files
Oak Park is known for its human diversity, but its arboreal diversity is equally noteworthy.
This was not always the case. During the first half of the 20th century, a uniform canopy of elm trees dominated Oak Park’s urban parkway landscape. Over the past 50 years, most of these elms have fallen ill due to Dutch Elm Disease, a fungus spread via the elm bark beetle or through intertwined underground root systems. The Village of Oak Park vigilantly and methodically removes these sickly trees.
Lesson learned. There is strength in diversity in more ways than one. Now the village makes a point and a policy of planting a variety of species to prevent a similar fate from recurring.
Case in point. At a recent block party on the 800 block of South Kenilworth, Gordon Waldron of The Learning Gardens gave adult residents a tour of their 39 parkway trees. There were 24 varieties including 3 maples (Silver, Norway, and Freeman), 4 oaks (English, Swamp White, and Chinquapin), and 4 elms (American, Hybrid, Morton Glossy, and Homestead).
With just one White Ash tree out of 39, the Emerald Ash Borer will not cause much mayhem when it moves to this block. In addition to Dutch Elm Disease, the Emerald Ash Borer is another major threat, having killed over 1,500 trees since it first invaded Oak Park in 2008.
On the tour, residents learned that Kentucky Coffee trees are so named because early white settlers made a coffee substitute by grinding and roasting its seeds, that the Little Leaf Linden grows an aromatic white flower attractive to bees, and that fast-growing trees are usually weaker than slow-growing varieties.
Mulching trees is a good idea for several reasons but should be done properly, in the shape of a donut, not too close to the base of the tree. Piling mulch on the tree itself at the base will create overly moist conditions that attract pests and disease. Placing a 4 to 5 –foot diameter of mulch around a tree trunk is ideal at a 3 to 4-inch depth. Mulch retains moisture, releases nutrients, prevents erosion, and moderates root temperature.
Gordon, a retired attorney, developed his love of trees by climbing them as a child. He used to give tree tours as a volunteer for the Forestry Commission and now does so for The Learning Gardens, an organization whose founders were instrumental in helping Oak Park attain its designation as a municipal Arboretum. Their next goal is to turn Oak Park into a Botanic Garden.
Cost for the tour is a $60 donation to the Learning Gardens. For more information or to reserve a tree tour for your next block party, go to: http://www.thelearninggardens.org/tree-walk-for-your-block-party
To see the Village of Oak Park’s interactive map of parkway trees, go to http://www.oak-park.us/village-services/public-works/parkway-tree-care-maintenance. Click on Village Tree Inventory under Useful Links. Then type in any address.