The fall is a great time of the year. The trees turn such beautiful fall colors and then those leaves fall to the ground. Tree leaves are fun to play in as a kid, everyone loves the crunch sound under your feet as you walk over fallen leaves. However, leaves shouldn’t be just left on top of our grass like when they fall from the tree. This can be damaging to our lawns and to surface water. So, it is best to utilize them or remove them.
Leaves should be removed from the turf in the fall. If left on the turf over the winter months they can smother the grass. They can also cause snow mold to develop over the winter. Raking the leaves will allow the turf to dry out on warm days with no snow cover to reduce the chance of getting snow mold.
Leaves can be a pollutant to surface water if left on the ground. Leaves left on the ground can be washed away into storm drains and other surface water locations. Fallen leaves release phosphorus and nitrogen when they decompose. If that decomposition occurs in the water, an overload of nutrients can contribute to impaired water ecology, such as excess algal growth (From Kelly Feehan, Extension Educator in Platte County Extension).
Other alternatives to raking leaves
Raking leaves can be quite a bit of work. As I drive around town, I notice some landscapes that contain quite a few trees, which as an Arborist, I love. However, in those landscapes it would take a long time to rake all of those leaves. And it really doesn’t matter when you rake up your leaves, it seems as soon as you are finished more leaves have found their way to your lawn. An easier way to do this would be to mow the leaves.
According to the UNL Turfgrass Department, mulch mowing can be easier than raking and it returns complex organic matter and nutrients to the soil. Some research also shows that mulch mowing can help control weeds. The weed control is sporadic, but it can be possible. So, this is a very beneficial alternative to raking the leaves. Mowing over the area at a higher deck height two or three times can help break down the leaves and incorporate them back into the turf for added nutrition for the lawn. Just as grass clippings don’t add to a thatch layer in the lawn, mowing over leaves and leaving them on the lawn will not add to any thatch layer in your turf.
Another use for the fallen leaves in your landscape would be to utilize them as a mulch in your gardens. You can bag them up and use them next spring or add them to your compost pile for the addition of carbon that is needed in any compost pile. Or you can rake them up and around your plants and trees for added winter protection. Be careful when you choose which leaves to use as mulch or additions to your compost pile. Leaves that were diseased this year, or had one of the many leaf spot diseases we saw this year, should not be used as mulch or in the compost pile. The compost pile will not get hot enough to kill the pathogens on those leaves and if left as a mulch around the tree, this could just reintroduce the disease to the tree next spring again. For those diseased leaves, it is best to just rake them and destroy them.