As the Town of Vienna rethinks the economic and human impact of its centralized leaf collection, maybe this is an opportunity to rethink the environmental impact as well.
In this post, I suggest something the Town of Vienna might do to reduce the environmental harm of centralized collection and disposal of leaves.
Briefly: Give equal footing to policies of “put your leaves out for collection” and “better yet, don’t do that”. That is, raise awareness that the most environmentally sound way to dispose of leaves is to let them decompose in your yard. At the same time, make sure that citizens are aware of the substantial harm that centralized leaf collection and disposal does to our local population of butterflies and other pollinators. Maybe offer little “rustic butterflies” to match the “rustic hearts” that are all over town, signifying a household that promises not to rake their leaves to the curb every fall.
A change of focus
In my just-prior post, I focused on the economics and value of the three options the Town of Vienna, VA is currently considering for collection and disposal of leaves. You can also read the abbreviated version in the post just before that one.
From that standpoint, it’s clear to me that the third option was clearly superior. Under that approach, Vienna would collect leaves from the streets and truck them directly to Loudoun Composting. This option would:
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- Reduce Town resources devoted to leaf collection and disposal by about $75K.
- End the wasteful practice of “free” mulch, that is, trucking loads of mulch to Town residents at no charge, when it costs the Town an average of $125 each to produce and deliver those mulch loads.
- Eliminate a blight on the neighborhood surrounding the Beulah Road property that the Town currently used to store, grind, and compost leaves.
- Liberate that Beulah Road tract for better uses, effectively gaining a unique 8-acre, $16M piece of free land in the Town of Vienna. That’s something that would impossible for the Town to purchase.
But suppose we took a different viewpoint. Suppose that, within reason, we focused first on minimizing the environmental impact of this process, and only secondarily on the money and human costs.
What, if anything, might we do differently? That’s the subject of this post.
Vienna, take some advice from your own Conservation and Sustainability Commission.
Source: October 2019 Vienna Voice,.
In the Town of Vienna, citizens receive a tremendous amount of reinforcement for the practice of raking leaves to the curb for Town pickup. Every fall, the Town newsletter repeatedly reminds us to put our leaves out. The Town posts temporary signage in the neighborhoods well in advance of the day of leaf collection to underscore that. As a resident, you then see all your neighbors (and/or their lawn services) duly raking (and/or blowing) their leaves to the curb, as instructed. Finally, you hear the Town’s crews, often working far into the night, vacuuming up those leaves and carting them off.
Truly, this is a long-standing seasonal ritual here in the Town of Vienna. Maybe not as much fun as Halloween, but every bit as much a part of the seasonal fabric of the year.
In all the time I’ve lived here, only once did I ever see anybody from the Town of Vienna stand up and (politely) point out what an environmentally destructive practice this is. In the October 2019 Vienna Voice, Susan Stillman of the Town of Vienna Conservation and Sustainability Commission summarized one of the many reasons you should not rake up and dispose of your leaves.
Let me quote an expert directly, regarding the point that Ms. Stillman made (emphasis mine):
Over winter months, a lot of butterflies and moths as pupa or caterpillar are in the leaf litter, and when you rake it up you are removing the whole population of butterflies you would otherwise see in your yard, ... Without the insects in the leaf litter, you also risk driving away birds that might have come to your yard looking for food to feed their offspring in the spring.
Source: John Sandor, postdoctoral research in turfgrass science at Tufts University, quoted in USA Today.
“Remove” in the quote above is a euphemism for “kill”. At least, in the Town of Vienna, and I suspect in almost all other jurisdictions as well. Here, the leaves get “hot composted”. Large piles of ground leaves are ideally managed so that decomposition heats the leaves to 140 F – 180 F (reference). The heat sterilizes the leaves, killing any weed seeds (at 180 F) or insects (at 160F) or plant pathogens (at 145 F, all temperatures per this reference).
The point is, it’s not as if you’ve sent your local butterflies off on holiday by raking your leaves to the curb for pickup. Between the mechanical stresses of leaf grinding, and the heat of composting, it’s pretty much guaranteed that you’ve shipped them off to die.
The sterilizing effect of hot composting is considered a positive feature by the end-users of the compost, precisely because it prevents the spread of weeds, diseases, and insects. It’s often referred to as pasteurizing the compost.
Beyond adding your little contribution to the insect apocalypse, you can read up on some of the other environmental downsides of raking and hot composting leaves. Any number of reputable sources will tell you the same things. (E.g., The National Wildlife Federation, the Suzuki Foundation, Xerces Foundation, Tufts University Pollinator Initiative, and so on and so forth.) These other downsides include but are not limited to:
- Increased methane emissions if the leaves end in a landfill. (Methane is a powerful greenhouse gas and accounts for about 10% of all U.S. greenhouse gas emissions on a C02-equivalent basis, per the U.S. EPA).
- Increased use of chemical fertilizers if homeowners (or their lawn services) substitute those for nutrients that could have been provided by rotting leaves.
- Increased consumption of fossil fuels used in gathering and transporting the leaves and any resulting leaf compost.
What do I do? I rake them off the lawn and put them on my garden. Like so:
Source: Wordless Workshop Post on recycling used coroplast sheet and nuisance bamboo into raised garden beds.
The leaves mostly decompose over the winter. (The raised bed pictured above was full to the brim last fall.) They also smother weeds that would otherwise take hold in the garden. The earthworms end up tilling the organic matter into the soil, improving the tilth of the garden bed. And, ultimately, it’s easier and more convenient than raking them into a neat roadside pile for pickup at the Town-determined time.
Let me try to drive this point home. Years ago, my wife and I planted a couple of pawpaw trees in our back yard. In our area, the pawpaw is the only host plant for caterpillars of the zebra swallowtail butterfly (reference). But if I were now to rake the ground bare under that tree each year, I’d be doing my best to convert my little bit of butterfly habitat into my own personal butterfly death trap.
P.S. , if you plant pawpaws, don’t eat the fruit.
Truly, this isn’t rocket science. Maybe, just maybe, vacuuming up all the leaves in a four-square-mile area, then sterilizing them by hot composting, may not be the best option for the environment. We have to do it to keep the storm sewers clear. We may do it as a service to property owners who value neatness above environmental impact. As I noted in my prior post, I think we probably have to keep doing it to be in compliance with our response to the Chesapeake Bay Act. But we really shouldn’t turn a blind eye to the negative consequences of it.
Toward a more balanced Town policy on leaf collection.
Encourage people NOT to rake their leaves to the curb.
Noted above, we here in the Town of Vienna get a constant stream of reinforcement for raking leaves to the curb for centralized collection. Notices in the Town newsletter, signs on the streets, and peer pressure all tell you that this is the thing to do.
Also noted above, only once did I see the mildest bit of dissenting opinion offered by the Town.
Maybe its time to change that. Maybe we could cut the Town’s costs and do a small favor for the environment by encouraging citizens to keep their leaves on their lots. Maybe it’s time to give this alternative viewpoint equal footing with our traditional raking-and-collection behavior.
Let’s be clear: That should not be the responsibility of our Department of Public Works. Their job is to keep the streets and storm sewers clear. They don’t need to be burdened with trying to get across the mixed messages of “it’s time to rake your leaves to the curb” and “it’s better if you don’t do that”.
But maybe the Town could make some attempt to get out this alternative message about keeping your leaves on your lot. And by some attempt, I really mean some attempt to give this message equal footing with all of the reinforcement we get to rake out out leaves for centralized collection and disposal.
The best way to get people’s attention on this issue would be to make leaf collection a separate cost. That said, I’m sure it would not be feasible to do what Fairfax County does, and have a separate tax for leaf collection services. They do that on an area-by-area basis, not on a house-by-house basis. (For just a tiny fraction of Fairfax County, for reasons that are not readily apparent.) Opting out of the Town of Vienna leaf collection would clearly have to be done house-by-house.
Source: Fairfax County government
But an alternative way to focus some attention on this issue might be virtue signalling. Maybe if you chose to opt out of centralized leaf collection, you could get a little sign to place on your lawn. Publicize your small act of suburban environmentalism along the lines of the “rustic hearts” that Vienna residents use to show they (e.g.) contributed some money towards feeding the hungry (and supporting restaurants) in our area (reference).
I suppose that in Vienna, you’d have to call that a rustic butterfly. Every fall, when the Town puts out its signs directing you to rake your leaves to the curb, you could put out your rustic butterfly, letting the world know that you’ve opted out of that program.
If nothing else, that would raise awareness. I’d bet that almost nobody in the Town of Vienna is aware of the environmental impact of centralized leaf collection and disposal. And an attractive seasonal lawn sign might be just the ticket to let people know that not everybody rakes their leaves to the curb every fall.
How many people around town are aware if this statement:
Source: The Xerces Society for Invertebrate Conservation.
Source: #leavetheleaves, from the Xerces Society for Invertebrate Conservation.
