Autumn Leaves and Rivers

Get some exercise and help prevent harmful algae in the St. Croix.




2 minute read

2013-11-09 16.12.21

I have to say it again, how lucky we are to live in such a lovely landscape. This year, the trees gave us an unusually long fall color season. Of course, the seasons bring change and now those beautiful leaves are littering the ground. When they fall on the ground, they decompose and replenish the soil with nutrients and organic matter. It’s a brilliant benefit and part of the natural cycle.

Decaying leaves can cause trouble too. Leaves and other yard waste left on sidewalks and streets commonly get carried away, by rain, into the storm sewers. Once there, this debris can wash directly into the river. While a benefit on land, these decomposing leaves can contribute nutrients to the river, which will promote the growth of algae next summer. It is not good to have algae blooms. Green rivers are not just an aesthetic issue. As excessive algae dies, it decomposes on river bottoms and uses up oxygen that fish and native plants need to survive.

By now you’ve probably figured out that I’m going to encourage raking leaves. Pull out that $15, non-electric tool, and spend a couple of hours outside. Concentrate on the hard surfaces around your home, including the sidewalks and alleys. Think of it as your workout for the day. There are health and wellbeing benefits, you can spend some quality time with the family if you convince the kids to help, and you’re not feeding the algae.

What do you do with all those leaves? Adding yard waste to your trash can isn’t the answer. Neither is burning leaves. Leaf burning produces air pollution, which reduces the health effects you’re trying to achieve.

Consider composting your leaves. Collecting your leaves in a bin and allowing nature to take its course can pay dividends. Compost can add a significant amount of nutrient back into your gardens and lawn. Fruits, vegetables, and grass thrive in soil rich with organic matter.

Leaves make great mulch. I use leaves to mulch my trees and gardens. You can use whole or shredded leaves. Mulching mowers will break down the leaves into small enough chunks to benefit lawns, if it isn’t layered too thick, again adding back organic matter to the soil.

I noticed the St. Croix Falls sweeper was out last week, doing what they can to keep a lot of leaves from entering the water. If your city doesn’t already do this, encourage them to start. But remember, just because your city has a street sweeper, that doesn’t mean you shouldn’t do your part. By the time the street sweepers drive by, lots of debris has already run down the drains to the river.

Most towns now have leaf drop-off sites. This works well for people who don’t have the space or inclination to compost leaves themselves. Many towns have adopted yard-waste pick up programs, where residents put waste in compostable bags for pickup. You’ll want to check with your city or county, or your regular trash hauler, about pick up services and drop off sites for yard waste.

Taking care of your leaves now will pay dividends. Grab a rake and a friend, and enjoy the autumn colors.


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Autumn Leaves and Rivers