I live in a suburbanized Oak forest North of Chicago. Today I saw that the village has cut down the remains of one of the younger Oaks in my neighborhood.
I’m 61 years old, and this tree existed before I was born, I know because I remember it being there when I was a small fry. There are many Oaks that are larger than this one, in fact the majority of them in my little suburb are larger in diameter. Not many Oak seedlings or saplings survive the lawnmowers and the other hazards that threaten Oak survival. This area, while predominantly Oaks (White, Red, Pin…), has also American Elm, (Yes! there are a few that have survived the great die-off from Dutch-Elm Disease in the 60’s), Cottonwood, Ash(suffering badly now due to the Emerald Ash Borer beetle), Hickory, and perhaps a few others indigenous to the area. What I find most disturbing is the lack of undergrowth to insure a continuance of the Oak/Elm biome. Sadly there are few young Oaks coming up under the magnificent crowns of these mature ones, some of which are getting close to 200 yrs or more in age! These big Oaks won’t remain if their babies are not cared for.
A small hollow is seen in the bottom of this tree, with some tunneling made by Black (Carpenter) Ants. This is not what caused the demise of this tree. Most likely its roots have been disturbed by the relaying of the bricks in the street to the right. Additional factors could be the percolation of rock salt used in Winter, application of lawn weed control chemicals, being overshadowed by neighboring trees, and the perpetual annual loathsome human habit of the raking and removal of leaves which happens every fall.
Importance of Soil Humus
Oaks, and indeed all trees, deciduous or evergreen, have developed before humans came along and raked up or disposed of their leaves. When undisturbed, the forest litter performs an important function for the health of a forest. It provides nourishment and acidification for the soil as well as a home for a myriad of insects, most of which are beneficial to the ecosystem. This is why I prefer to ‘lawnmower mulch’ the leaves in place and let the small bits filter down into the lawn. All of the nutrients and acidic tannins from the leaves will percolate down into the soil and ultimately help the trees in the following seasons.
What can we do?
If you like Oaks and their related forest dwellers as much as I do, then you can help by planting some acorns, or moving a seedling which is too close to a fence or a house into a more open spot in your yard. Mulch your leaves, or allow a humus layer to develop underneath your trees. Limit your use of weed killers. Important!: Oaks have a tap root, so when you go to move one, do not chop off the tap root!, and dig a deep enough hole to accommodate it. Do not indiscriminately hack off roots that may be going across the surface of your lawn, you might kill a tree. Be careful when digging for other plantings, if there’s a large root in the way, you can always choose another spot. Be kind to your Oaks!
A Classic Oak Crown – This magnificent tree must be approaching 300 years old or more, there are several large trunks which emerge from a stout base that looks to be 12 to 15 feet circumference. This one is a block away from my location, and looks like three trees in one. Most trees in the neighborhood are comparable to just that one trunk rising at the right.