|For environment’s sake, fallen leaves are best left in garden
Summer is turning into autumn, and the trees are shedding their leaves. Falling leaves are part of a natural cycle, but “natural” doesn’t mean harmless when it comes to excess leaves in our waterways. They can be a source of water pollution.
It starts with leaves that fall into the gutter or street. From there, they are blown or washed into storm drains, and then rainwater transports the leafy mess straight to our creeks. Once in the water, the leaves decay and generate unwanted nutrients like phosphorus. This fuels the rapid growth of algae, creating that unpleasant green slime on the water’s surface. The algae eventually decomposes and uses up the oxygen in the water, suffocating fish and other aquatic life.
Even if the leaves don’t make it to the creeks right away, they still threaten water quality. When allowed to accumulate in street gutters, catch basins or ditches, they mix with water and create a “nutrient tea.” This concoction is eventually carried to the creeks, where the excess nutrients degrade water quality.
If protecting our creeks isn’t reason enough to pick up those leaves, did you know blankets of large leaves like maple and sycamore smother and weaken lawns, and can create habitat for fungi and pests? Also, leaves on walkways and driveways are dangerous slip hazards. So for many reasons, those excess leaves need to be cleaned up!
Keep them off the street
Stay on top of leaf cleanup to keep it from becoming too daunting. Think of raking as exercise – it burns almost 300 calories an hour. Start by sweeping or blowing leaves from the sidewalk, gutters or street back onto your property for raking. You can also use a tarp on the pavement as a “dustpan” to collect leaves. On your property, rake up small piles as you go. Again, a tarp makes for easier collecting and dumping into the yard waste cart or bags, or transporting leaves to a compost pile or garden bed.
Composting is an efficient way to take care of fallen leaves and add valuable nutrients to your garden. You also save time by not bagging up the leaves. If your garbage hauler doesn’t provide regular yard waste pickup, you also save money because you’re not paying for extra disposal. And you eventually get a free, valuable product: One shade tree can produce $50 worth of compost and humus for your garden.
Locate your compost pile in the corner of your yard, beneath a stand of trees, or in the garden beds. For the best compost, make the leaves smaller first by grinding or mulching. Add nitrogen-rich amendments like kitchen scraps, green grass clippings or manure, as the leaves alone won't make compost. Turn the pile every three weeks or so, and by spring you will have your own homemade compost.
Another great way to keep the nutrients from leaves in your garden is to use a mulching mower to create a top-dressing for your lawn. Depending on the size of the leaves, you may need a couple of passes with the mower to chop them up. Leave enough mulch on your lawn to blend in nicely with the turf, but not so much that the grass suffocates. As the leaves decompose, they add organic matter to the soil, improving its quality.
Leaf mulch is also amazing for your garden soil. If you have a bagger on your mulching mower, you can collect the chopped leaves and mulch your flower and shrub bed. Smaller leaves or broken down leaves can be raked onto bare soil areas, or can be tilled directly into the soil. The resident worms will eat the leaves and digest them into worm castings, enriching the soil!
Disposing with yard waste
And of course, if you have more leaves than you need, they can be disposed of in the yard waste carts. Most of the Sonoma and Mendocino County cities have curbside collection of yard waste. Contact your City Hall or local hauler to learn what services are available in your community.
Keep leaves off the street for healthy creeks and use them in a multitude of ways for a healthy garden. Cleaning up and using autumn’s leaves helps the environment, and us naturally.
This article was authored by Eydie Tacata, Management Analyst for the City of Rohnert Park. RRWA (www.rrwatershed.org) is an association of local public agencies in the Russian River Watershed that have come together to coordinate regional programs for clean water, fisheries restoration, and watershed enhancement.