Leaves: How Nature's Gift Becomes a Menace

Many homeowners find it convenient to rake or blow their leaves to the curb each fall. The leaves are then scraped off the pavement and hauled out of town to be composted. There may be some logic to this approach, but there's also considerable illogic at work. The illogic plays out in many ways: expense, the hazards of blocked traffic and bike lanes, global warming gases from all the scraping, hauling and industrial composting, nutrient runoff into streams, impoverished and hardened urban soils, bias against homeowners on busy or narrow streets, and a scarred streetscape. Here are photos that illustrate some of the downsides.

Leaf piles in the streets push bicyclists and pedestrians (on streets with no sidewalks) out into traffic lanes. I've heard of near misses, particularly at night.

Cars, too, must swerve to avoid leaf piles. Here's a common situation. Police records show at least two auto accidents precipitated by leafpiles.

Removal of the above leaf pile left a dirty street and scarred ground. Rains will sweep nutrients from the remaining decomposing leaves and bare dirt into the local waterway, adding to nutrient pollution.

The irony is that regulations require that silt fencing be installed at construction sites to prevent the washing of sediment into our streams, and yet uncontainerized leaf collection exposes dirt and coats long stretches of streets with leaf residue that can then wash into those same streams.

Loose leaf collection discriminates against homeowners on busy streets, where they must pile their leaves on the grass rather than the pavement. Covered by leaves, the grass quickly dies, leaving bare dirt far into the next summer.

Grass also gets killed on narrow side streets like Chestnut. One exasperated resident of very narrow Bank Street told me of the racket caused by a landscape crew that blew leaves from the backyard into the street, where they interfered with traffic for many days.

It's ironic to see this fertilizer sign on a lawn facing Hamilton Ave, while at the same time the lawn service is killing the grass with piles of leaves. You could ask "What are people thinking?", but I doubt much thinking is going on. Rather, there's a blind adherence to two customs: fertilizing lawns and blowing leaves towards the street.

Princeton main thoroughfare, Nassau St, should be a pride and joy, but the decorative flags and hanging flower baskets during the summer contrast with the lingering scars left behind by fall leaf pickup.

Here's another stretch of Nassau Street left bare and muddy after the grass-killing leaf piles have been removed.

And then there's the actual scars on the pavement, left behind by the "claw" that picks up the leaves.

It's hard to photograph the annual expense, which may be up around $1 million, or the hardened, leaf-cheated urban soil that sheds rain and adds to flooding, or the fossil carbon rising from all the public works department's machines to speed climate change.

Some people think that the answer lies in education and better enforcement of the town's leaf ordinance. I used to think the same. But past education efforts, of which I was a part, had negligible impact. Enforcement was tried, proved time consuming and was abandoned. Robo calls with schedule reminders have helped some, but it's doubtful that landscape crews, with rapid employee turnover and language barriers, will ever coordinate their work to conform to the town's five zone leaf pickup.

Blowing leaves into the street is much like being allowed to send underground carbon up into the air as CO2 from our exhaust pipes. The legacy of all that private convenience is a shared public burden. Deprived of the convenience of doing environmental harm, we would respond, as humans do, by being resourceful and inventive. In the case of leaves, we'd mow some of the leaves back into the lawn and blow others into a back corner of the yard to kill the weeds. We'd devote a tiny portion of our (largely unused) yards to leaf corrals that return nutrients to the soil, and if need be we'd stuff any leaves left over into yardwaste bags and rollcarts for efficient pickup. We'd take as our inspiration nature itself, which never hauls valuable nutrients away, but keeps them close by, to return to the soil from which they came. And we'd take pride in clean and verdant streetscapes.

Princeton doesn't need to be spending $1 million for a brand of leaf management that forces us to navigate through a scarred mess much of the year. We're better than this.

Use Those Leaves in the Yard

This fall, rather than dump leaves in the street or stuff them in bags, consider these options.

Mow them back into the lawn

The easiest option by far is to mow the leaves back into the lawn--an approach recommended by county extension offices around the country, and even by company sites like Scotts Miracle Grow. They've studied it, and concluded that the ground up leaves provide valuable fertilizer for the lawn, and do not cause any problem with thatch.

Some kinds of leaves make this method particularly easy. Pine needles and honey locust leaves are so small they don't even need to be chopped up by a mower, or can be raked underneath shrubs to serve as a mulch. Leaves of silver or red maple also tend to "melt" back into the lawn, decomposing quickly.

Grind leaves up with an electric leaf mower/vac

This will take care of leaves the lawnmower can't reach. Electric leaf blowers are quieter than the gas varieties, and some designs can be reversed to vacuum up leaves and grind them. I have not tried this method, but the NPR show You Bet Your Garden had a segment singing the praises of leaves ground up this way as mulch for flower beds. Even if you buy locally, you can check out reviews of various brands here on Amazon, with prices well under $100.

Make Room(s) For Leaves in the Yard

If you choose to collect leaves into piles rather than grind them, the question becomes where to put them if not on the street. One factor that makes people more likely to blow leaves out to the street is that most yards lack "rooms." The typical yard has shrubs pushed against the house and fenceline, defining only one sprawling "room" that extends uninterrupted to the curb, all of which is then required to be ornamental.

Houses have rooms that separate utility and storage from living areas, so why not yards? If you use shrubs or wooden walls to define and screen small utility areas in the yard, it becomes very easy to store leaves while they decompose and slowly return to the soil from which they came. Nature's miraculous trash-free economy is then allowed to function, and we're spared a big mess in the streets and the considerable municipal cost of hauling, grinding and mechanically turning leaves at a distant composting center.

The photo shows one such configuration in a friend's backyard. The wall provides screening between the utility area with compost pile and tools, and the ornamental garden to the left.

Another way to break up space and screen a leaf pile from more ornamental areas is to plant shrubs out a distance from the fence. The leaves can then be piled inbetween the shrubs and the fence. Though a back corner is the most logical location, the one in the photo is next to the street.

Here's the view from the street. The shrubs are privet, but a native evergreen alternative would be inkberry (Ilex glabra). Other smaller native shrubs--not evergreen but with attractive flowers, would be Itea virginica, Clethra alnifolia or Fothergilla. The main idea is to reconfigure how shrubs of any kind are planted in the yard, so as to create refuges for leaf piles that will quickly be flattened down by the weight of rain and snow and benefit shrubs and trees through the steady process of decomposition. Sectioning off a "room" in the yard also breaks up the monotony of shrubs lining the fenceline and foundation.

Whether ground up or piled in a corner, leaves serve as a natural fertilizer and increase the capacity of the yard to absorb rain. The more organic matter a yard contains, the more moisture it can hold, which helps buffer the yard from extremes of rain and drought. A soil rich in organic matter welcomes the rain, which in turn reduces runoff into the streets and, collectively, the amount of flooding downstream.

Winter Gives Way To Yardwaste Season

Southern Michigan, where I used to live, was said to have two seasons: winter and road construction. It was a gloomy assessment, but sometimes seemed all too accurate.

Thankfully, Princeton lacks the interminably grey winters of southern Michigan, and is bikeable enough that road construction is less often an obstruction. But for those who walk borough streets, it feels more and more like the town's two seasons are winter and yardwaste. Winter lasts roughly from January through February, during which one can enjoy clean streets if it doesn't snow. With March comes the first modest dumpings at the curb,

which continue through the summer and into fall, climaxing with the blitz of leaves that threaten to obscure the pavement altogether.

I try to imagine that this tradition reflects a dogged effort to do away with pavement and turn Princeton into one large greenspace, but the reality is that a whole bunch of soft, rainwater-absorbing material is being exported, making Princeton's yards less absorptive of rainwater, and more apt to amplify flooding.

It's not that hard for most homeowners to make a little spot in a back corner, screened by some shrubs if desired, where leaves and even some brush can be tossed. Take advantage of nature's onsite recycling services, and make a spot this year where a little dk is ok.

Are Rollout Bins Right For Princeton?

If New York is the city that never sleeps, Princeton has become the town whose streets are never clean. The dumping of yardwaste in the streets is now year-round. Municipal fear of taxpayer outrage may be the reason that ordinances meant to control the dumping activity, and to bring Princeton in to compliance with state regulations, go unenforced.

There are places in America that have clean streets. I know because sometimes I jump on my horse and ride towards the horizon to see how other people live, and can say definitively that we can rescue ourselves from this self-imposed squalor.

Take San Francisco as an example. Once a week, three rollout bins are placed at the curb. Gray is for trash. Blue is for recyclables. Green is for a combination of foodwaste and yardwaste.

Because the yardwaste is containerized, collection is efficient and the streets remain clean. Of course, this neighborhood has fewer trees than Princeton does and thus less generation of leaves and brush. But there are many tree-packed municipalities that don't allow dumping of leaves on the street, and instead expect residents to compost most of them in the backyard and place the rest in rollout bins and yardwaste bags at the curb.

This sign shows what goes in the green bin: food-soiled paper, food, and yard trimmings. All of this gets composted outside of town. Princeton township began offering this service last year, and recently extended service to anyone in the borough willing to pay $20 a month. (More on this in another post.)

One of the benefits of rollout bins is that their contents are mechanically emptied into the trucks. Princeton's recyclables and the borough's trash are lifted manually into trucks, which puts workers at risk of back injury. The lack of rollout bins also means that residents must do heavy lifting to get their trash and recyclables to the curb.

Some trucks can actually grab the rollout bin at the curb and dump its contents without having a worker on the street.

When in the past I've recommended that Princeton shift over to rollout bins, the idea was reflexively rejected due to concerns about the cost of this sort of truck. Imagine my surprise when I saw one of these trucks collecting trash in Princeton township. Midco, one of the private haulers township residents can contract with, has obviously seen the cost savings in this approach.

Consolidation of Princeton township and borough into one entity offers an opportunity to reshape services. Rollout bins have worked elsewhere and are now being utilized by private haulers in the Princeton area. It's time the municipality look at ways to put them to use.

Harvest Gone Wrong--2008

Each weekday morning, kids and parents stream down Abernathy Street to get to Little Brook Elementary School. This time of year, leaves on the street make the morning and afternoon rush hours a little more dangerous, as leaves piled on the street constrict traffic flow and turn slippery in the rain.

The township, responding to a state mandate, requires that leaves not be put on the street until one week before the monthly pickup, and that the piles extend no more than three feet out from the curb. This pile, a common sight, was set out two weeks before scheduled pickup, and extends ten feet out.

As often is the case, this was the work of a landscape crew from out of town that seems oblivious to local regulations.

The second photo, dramatizing the hazardous aspect of leaves dumped in the street, gives evidence of a car skidding through a stop sign on rotting leaves, in a busy intersection crowded with kids twice a day.


The third photo shows a small victory for sanity. A homeowner who used to have the leaves in her woodlot blown into the street every fall has had a change of heart. She now piles some in three wire bins, and spreads the rest in a well-defined area under the trees, enriching her soil and leaving the street clean.

Free Leaf Compost and Wood Chip Mulch

If you're looking to improve your soil or put attractive, dark mulch around your flowers and shrubs, you can get composted leaves and/or twice-ground, composted woodchips for free about 5 miles out of town at the Ecological Center in Lawrence Township. Most of Princeton's leaves go there in the fall, and if you can borrow a friend's pickup or figure out some other way of carting it back, you're in luck.

For $9/yard during weekday hours, they'll load it on your truck with their front-end loader. No cash accepted. Take a checkbook. If you want it for free, take a pitch fork or shovel along.

Location is 3701 Princeton Pike (called Mercer in Princeton), and hours this time of year are 7:30 to 2:30 M-Sat. More info are at http://www.princetonboro.org/polDoc.cfm?Doc_Id=161.

According to the man on duty, the Center gets maxed out from all the leaves coming in in the fall, and does not accept the mixture of leaves and brush the town crews collect from Princeton streets this time of year. All of that goes to a private business a mile or two further down the road.

Making Use of Fallen Leaves in Your Yard

The previous post (below) tells why raking all your leaves to the curb is not such a great idea. There are lots of reasons to think of leaves as an asset rather than a burden. Here are some ways you can use leaves to advantage in your yard, whether it be large or small.

1. The simplest thing to do is rake/blow them into a woodlot, if available.

2. Rake them against the fenceline, where they can serve as a mulch to keep down weeds that often dominate along fencelines. Or dump them on any other weeds or groundcovers that are getting out of control. A thick layer of leaves discourages weeds. For weeds/groundcovers strong enough to push up through the leaves, first place overlapping pieces of cardboard on the undesired plants, then use the leaves over top to hide the cardboard.

3. Rake them into a leafpile. A corral or circle of wire fencing will help contain the leaves and keep them from blowing around. A readily available fencing is 3 feet high, green, and comes in rolls at the local hardware store. (Photo shows enough fencing for several corrals). The corral is essentially invisible when tucked in a back corner of the lot. A U-shape may be preferred so that leaves can be dragged, blown or raked right into the enclosure rather than lifted over the fencing. The leaf pile quickly reduces in size over the winter. The leaves can be left to decompose, acting like a sponge to catch the rain, and releasing nutrients to benefit the health of all trees and other landscaping in the vicinity. Contrary to popular notions of composting, it's not necessary to laboriously turn the pile. Just let it decompose over time. My experience is that a pile of leaves does not create odors.

4. Spread them on the vegetable garden and leave them there to hold in moisture, prevent weeds from sprouting, keep the soil cool in the summer, and slowly release nutrients. Planting tomatoes, for instance, requires nothing more than parting the leaves to put the new plants in. The leaf mulch reduces rotting of any tomotoes that touch the ground.

5. Mulch them up with a mower so they can disappear back into the lawn. The fragmented leaves can also be raked onto flower beds as a mulch. Some leaves, like those of silver maples, crinkle up and all but disappear into the lawn on their own, even before mowing. For thick, persistent leaves like those from a red oak, a corral or the mulch mower approach will keep them from blowing back into the yard.

HARVEST GONE WRONG

A vast deluge of leaves will soon be falling on Princeton, and the question is what to do with them all. For as long as can be remembered, most people have raked them into the streets and let the town scramble to clear away the resultant mess. Given how much homeowners pay in property taxes, it's understandable why people feel they should take advantage of one of this high-visibility service the town provides.

But I would argue that this tradition is needlessly expensive, dangerous and destructive, and that there are alternatives that could easily be adopted by most homeowners without any aesthetic or physical sacrifice.

Consider the above photo, taken last fall, which shows how one homeowner goes to the trouble of cleaning a woods. The homeowner no doubt likes things tidy, which can be seen as admirable, but let's take a look at the string of events this purging of leaves from the property sets into motion:

Leaves that were providing nutrients for the trees, and protection against soil erosion, are blown by a hired crew out into the street, where they block traffic near a school, pollute the local streams and must then be hauled out of town at community expense. In other words, leafblowers are used to create a solid waste problem, requiring more machines to carry the leaves away, grind them up for industrial-scale composting, then haul the leaf mold somewhere for final use.

In the age of global warming, it's hard to rationalize the extravagant consumption of fossil fuels this landscape practice demands. If the homeowner is not comfortable with the blanket of leaves the trees are trying to lay down for themselves, a much less harmful alternative is to place them in a wire corral in the back corner of the property (see post above).

But needless fuel consumption is only one of many reasons why the status quo is harmful to the community:

Increased Flooding: The annual mass removal of leaves from the urban landscape reduces organic matter in urban soils. This makes the ground less able to absorb rainwater, which increases flooding in local creeks.

Water Pollution: Though it's not obvious from the looks of things, the streets we walk on, drive on and dump stuff onto are essentially dry creekbeds, directly linked to the town's streams. Leaves dumped in the street invariably get rained on, start to decompose, and then release nutrient pollution into waterways before they can be picked up.

Energy consumption: If the township and borough are going to reduce energy consumption by 25%, in an effort to reduce the local impact on global warming, one place to start is by reducing the need for big rig caravans scooping or vacuuming up leaves along the street. In the borough, it's impressive to watch The Claw deftly scooping up leaves, but it burns a lot of gas, as do the massive grinders that triple-shred the leaves out at the Ecological Center. The export of leaves from town also requires burning more gas to then haul them back into town, in the form of mulch and compost.

Safety: Leaves on the street force cars out across the center line, and can cause fires if hot mufflers or catalytic converters on parked cars touch dry leaves. Where there are no sidewalks, pedestrians and bicyclists are forced towards the center of the street. Blockage of stormdrains by leaves adds to these problems.

Tree health: If we want to promote healthy trees in town, it's hard to imagine a happier tree root than one infiltrating the rich leafmold on the underside of a leafpile.
Most properties with big piles of leaves out at the curb have room on their lot for a leaf pile that will quickly and dramatically reduce in size over the winter. Perhaps there's a way to mix education and an incremental change in policy that would allow Princeton to trade one tradition for another that makes more ecological and horticultural sense.

Expense and diversion of staff from other municipal services: Leaf collection increases wear and tear on town vehicles and draws town crews away from other services they would ordinarily provide yearround.

Grass Clipping Update

In response to a state law passed some time ago, Princeton Borough is no longer picking up grass clippings from the streets (http://www.princetonboro.org/public_works.cfm). Grass clippings clog drains and their nutrients can leach into local streams. The stormwater system underlying town streets feeds directly into streams, so dumping anything on the street is essentially the same as throwing it into the local brook.

Some homeowners hold to the belief that grass clippings left on the lawn cause thatch buildup, but the Mercer County Extension service does not recommend removing them. They are high in beneficial nutrients and decompose quickly. They can also be composted if mixed with other organic materials. Go to http://www.mgofmc.org/successfullawncare.html for more info.

Unfortunately, many homeowners, not having gotten any clear feedback from the borough, are still dumping grass clippings out on the streets, making ever larger piles. Maybe someday there will be a good feedback system developed so the policy is made clear to those who can't take a hint.

Leave Grass Clippings On the Lawn!

If the borough ordinance forbids putting lawn clippings out on the road, why do the street crews keep taking them away? Good question. Even in a government bureaucracy as small as Princeton Borough, there are contradictions. Though street crews are showing a generous nature, the result is that neighbors imitate other neighbors, and soon the whole block is violating an ordinance intended to prevent high-nitrogen yardwaste from polluting the nearby creek via storm sewers.

Sometimes, it's a misinformed landscape business that is first on the block to dump illegally.

Word has it that the borough may eventually start fining homeowners who put grass clippings out on the road.

The Mercer County Master Gardeners recommend leaving grass clippings on the lawn (http://www.mgofmc.org/successfullawncare.html). If you don't, you're lawn loses valuable nitrogen that must then be replaced by buying more fertilizer. The worst thing to do with grass clippings is to pile them up. The high nitrogen and lack of aeration favor anaerobic bacteria that raise a stink if the pile is disturbed.

Meanwhile, in the township, it appears that there is no yardwaste pickup at all in June and August. More info can be found at www.princetontwp.org/pubworkmain.html.