Why Cleanup Leaves?
By Alexander VanDorpe


You care about how your yard looks, right?  If you didn’t, you probably wouldn’t be spending the time to read this right now!  Many people spend much time, effort and money every year to make their lawn look as nice and luscious as possible.  They may meticulously mow every week and hire a company to apply fertilizer and spray for weeds.  Edging walkways and sidewalks may become a Spring and Summer tradition as well.  But did you know that ignoring fallen leaves in the Fall and Spring can could cause harm to your lawn despite of your best efforts?

Fallen leaves that sit on grass for a period of time will block out sunlight and reduce water evaporation, which prevents the grass from breathing.  Remember, your lawn is a living and breathing plant too and it needs all the help it can get!  When grass is “choking,” due to a lack of sunlight and excess moisture, it has a very difficult time growing new blades or repairing previous damage.  A layer of leaves just invites pests and diseases to inhabit a lawn.  This leads to fungus, mosquitos, mold and other diseases, which can destroy a lawn in a single season.

Some of the more common diseases is Snow Mold – discolored grass, straw-colored or containing a white or pinkish coating (like a spiderweb) that appears in early Spring.  These spots can shrink as the weather dries out and warms up, but sometimes they may remain into the fall.  They are caused by two fungi – gray snow mold, Typhula spp (Typhula blight) and pink snow mold, Microdochium nivalis (Fusarium patch).   These fungi are resistant spores and easily survive high summer temperatures while remaining inactive.  Then, when the temperatures are around 32 degrees to 45 degrees in late winter, the snow cover begins to melt and the fungal infections spread until temperatures are consistently above 45 degrees.  Pink snow mold is even worse, remaining active as long as moisture exists and temperatures are below 60 degrees!  As a result of these types of fungal infections, noticeable damage will be present in the early spring when the ground begins to thaw and the above conditions are present.  While the resulting spots are not extremely serious, they do look quite bad in the middle of a well-maintained lawn and can take an entire season to grow back in, assuming you put down new seed in those spots!

As we live in a “cool-season” state in Iowa, it is important to remember that the rejuvenation period for these types of grasses, such as Kentucky Bluegrass, is in the Fall and Spring.  The most important factors are sunlight and moderate temperatures.  To help our customers’ lawns achieve this, we offer a Fall Cleanup and a Spring Cleanup, as well as mulch mowing.  Does mulching your leaves help?  Yes, but only to a point.  If your leaves are large, such as oak leaves, it could take several passes with a commercial-grade mower to chop them up finely enough for them to settle down between the blades of grass.  This is the goal of mulching – to get very small pieces of leaves out of the way of the sunlight hitting the blades of grass.  With a great deal of large leaves, it is probably better to remove them.  Smaller leaves, such as locust leaves will mulch much easier and may not require removal.  We recommend BOTH the Fall and Spring Cleanup services -even though your lawn may be 100% leaf-free before the first snowfall, the winter winds, combined with any lingering leaves in your neighbors’ trees (or neighborhood!) will most likely deposit unwanted leaves onto your lawn.