In the past, yard waste went to landfills, just like other types of waste produced around the home. In 1993, Wisconsin passed a law making it illegal to dispose of yard waste in landfills.
Unlike some other types of household waste, yard waste is organic: that is, it is biodegradable. However, waste does not decompose in landfills. This is because in landfills, waste is packed in tightly, preventing air from circulating. Without air, the organisms that normally would break down the waste are unable to survive and do their jobs.
Some organisms can survive these conditions. Though these organisms are able to break down waste, they do so through a process that produces methane, a powerful greenhouse gas.
Sending organic waste to a place where it either does not decompose, or decomposes in a way that contributes to climate change, is not a good practice. In addition, before the 1993 law went into effect, up to 20% of the landfill-bound waste stream was organic yard waste. That just takes up a lot of space!
A better way to deal with yard waste is to let it decompose in a way that produces healthy soil, instead of greenhouse gases. Currently, Madison collects yard waste and takes it to be composted centrally. This collection process, however, comes with its own harms. First, yard waste awaiting collection sits on or near the street, where nutrients can leak out of it and pollute our lakes. Second, collection is done using large trucks, which burn fossil fuels and make a lot of noise.
The need for collection of yard waste can be reduced if homeowners compost their own waste in a corner of their yard. In addition, yard waste itself can be reduced by eliminating unnecessary cutting of plants.