Green Thoughts

My Pile: Chip, Chip, Hooray

Posted by

0

With the yard cleanup complete and my pile put to bed for the fall, it’s time for another favorite backyard project: Dressing my beds of perennials and the forsythia hedges with a layer of fresh wood chips.

Over the years, I’ve spread truckload after truckload of the remains of all manner of local trees and bushes, sawed into chunks and run through an industrialized chipper by a local landscaping crew, flagged down to dump their results in my driveway. If it’s not grass or patio or pavement, the ground I tend is covered by a layer of what toney landscapers call arborist mulch, where it decomposes according to its own composition and timeline.

Each fall I replenish the garden beds of perennials with a fresh layer of wood chips.

Each fall I replenish the garden beds of perennials with a fresh layer of wood chips.

Wood chips aren’t quite as virtuous as compost, ecologically, but they do have their benefits to the backyard gardener. A four-inch layer of chips spread among my perennial beds prevents weeds from sprouting. It soaks up rainfall and slowly releases it, drastically reducing the need to water the flowers, bushes and shrubs that ring the perimeter of my property and surround the house.

A blanket of freshly minced trees gives the ground underneath the forsythia hedgerow and around the trees a uniform, manicured appearance, though for a few weeks my yard has the look of the kid with the bright new sneakers at school. And for a time, especially after it’s wetted by the first rain, a freshly spread layer of chips gives my yard a Christmasy, pine-scented smell or, when I happen upon a load made of black birch, a hint of Wrigley’s peppermint gum.

Some of my neighbors landscape their properties with store-bought mulch, made from coconut husks or nut shells or ground-up bark processed from who knows where – often dyed an unnatural shade of red or coffee brown. I prefer to get my wood chips unvarnished and for free, from nearby, and to spread them myself. I also like knowing where the chips come from, as an unsourced load of chopped-up tree or brush could introduce some blight or bug into my landscape. I’m pretty sure one year I got a nasty case of poison ivy after spreading a load of chips infused with ground-up ivy vines.

Still, the virtues of mulch are plainly evident.

“The greenness and fertility of my garden are due to vast quantities of mulch, everything from compost to salt hay to seaweed,” Eleanor Perenyi extolled in her garden classic, “Green Thoughts” (Modern Library, 1981).

“To non-organic gardeners, mulch’s primary function is to keep down weeds and conserve moisture in summer; in winter they may use [it] to keep the soil from freezing and heaving around favored perennials. But to gardeners of my persuasion, mulch is much more: It is an organic substance whose benefits extend to the soil itself, improving its structure and enriching its fertility to the point where it needs nothing else. An organically mulched vegetable garden never requires tilling, digging or hoeing, and is scarcely weeded. [Mulch] doesn’t burn or cause sudden spurts of unhealthy growth as artificial fertilizers may – it is long-term in its effects.”

Perenyi was not much in favor of wood chips, seeing them as too expensive when purchased commercially, a “staple of every corporate planting,” and low in nitrogen, requiring the addition of a fertilizer to compensate [more recent research seems to refute that, as you’ll see below]. Still, she was wholly committed to using mulches that were to her liking, “even newspapers and old carpets.”

My qualms about adding so much wood chip mulch to my grounds are assuaged by some online browsing. My search for “composting wood chips” brings me to a collection of web pages produced by Washington State University and composed by an expert I soon recognize as the modern maven of mulch, Linda Chalker-Scott.

In a 2007 newsletter produced by Master Gardener,  Chalker-Scott, who is a Ph.D. , Extension Urban Horticulturist and Associate Professor, and MasterGardener WSU editor at the Puyallup Research and Extension Center, Washington State University Puyallup, explains:

“In areas where trees are a dominant feature of the landscape, arborist wood chips represent one of the best mulch choices for trees and shrubs. A 1990 study evaluated the landscape mulch potential of 15 organic materials, including grass clippings, leaves, composts, yard wastes, bark, and wood chips. Wood chips were one of the best performers in terms of moisture retention, temperature moderation, weed control, and sustainability.

“In many urban areas, arborist wood chips are available for free, representing one of the most economically practical choices. Unlike the uniform nature of sawdust and bark mulches, wood chips include bark, wood, and often leaves. The chemical and physical diversity of these materials resists the tendency towards compaction seen in sawdust and bark. Additionally, the materials vary in their size and decomposition rate, creating a more diverse environment that is subsequently colonized by a diverse soil biota. A biologically diverse soil biota is more resistant to environmental disturbance and will in turn support a diverse and healthy plant population.

“Wood chips are considered to be slow decomposers, as their tissues are rich in lignin, suberin, tannins, and other decomposition-resistant, natural compounds. Thus, wood chips supply nutrients slowly to the system; at the same time they absorb significant amounts of water that is slowly released to the soil. It is not surprising that wood chips have been cited as superior mulches for enhanced plant productivity. Wood chips have been especially effective in helping establish trees and native plants in urban and disturbed environments. Arborist wood chips provide incredible weed control in ornamental landscapes. The mechanism(s) by which wood chips prevent weed growth are not fully understood, but probably include light reduction (preventing germination of some seeds and reducing photosynthetic ability of buried leaves), allelopathy (inhibiting seed germination), and reduced nitrogen levels at the soil-mulch interface (reducing seedling survival).

“While there are imported wood mulches available for purchase at nurseries and home improvement centers, they are not as cost-effective as locally produced wood chips, which are often free. In a society where using locally produced materials is increasingly popular as a measure of sustainability, arborist wood chips are a natural choice. Finally, the reuse of plant materials as mulches keeps them out of the landfill—a benefit with both economic and environmental attributes.”

In any event, over a season or so, the wood chips spread across the bare ground are broken down by rot and mold and earthworms to become a deep new layer of biomass that is easily tillable. True, sometimes a layer of chips gets permeated by a web-like tangle of fungus, and I’ve read that decomposing wood chips can suck available nitrogen from the soil underneath and turn the ground more acidic than some plants favor. What’s more, all that wood decomposing does add a measure of carbon dioxide to the atmosphere.

But on balance, a blanket of local, fresh-made chips spread around the walkways and untended areas saves energy all around. It lays the groundwork for healthier plants, especially when combined with compost, which I tuck around the perennials and spread across my vegetable garden and atop the densest patches of my plantings. It all makes my yard that much more of a biomass factory, though I marvel at how all that minced wood reduces to so little. I realize what I’m shoveling is mostly water and air, bound only for a moment of time into bite-size pieces of carbon.

Earlier this week, I turned out the dog for his morning relief just as a cherry-picker and a truck hauling a chipper lumbered past my driveway and stopped two houses down the street. They were there to remove a big old white pine overhanging a neighbor’s house. After watching the driver expertly back the truck and chipper up the narrow drive, I asked if he wanted to dump the chips in my driveway.

Good for him, good for me, as it’s a no-brainer to drive a truck 30 yards down the street rather than 30 minutes to some rural landfill or refuse yard. And sure enough, when I came home at the end of my work day, my driveway was covered with a pile of fresh-cut wood chips wide and deep enough to hide a car.

 

A freshly dumped load of wood chips nearly fills my driveway.

A freshly dumped load of wood chips nearly fills my driveway.

By now, I’ve got the process down, if not to a science, then a sport. Come Saturday, I am ready to dish. I use a wheelbarrow, a hay pitchfork with four curved tines and an old wide shovel I use to plow snow off my driveway.

I get started by leaning the wheelbarrow sideways into the pile and filling it with chips dragged from the top of the pile with the pitchfork. As the pile reduces, I use the wide-mouth shovel to scoop up from the edges. I know just how many fork-fulls or scoops it takes to fill the wheelbarrow and have a good idea of how best to wield the wheelbarrow around the garden beds to keep from burying an azalea or phlox.

Besides, wood chips – especially this load of light, bright-yellow pine, flecked with minced green – is easy to work with.

I can work my way into a dump-truck-size pile in less than a day, replenishing all of my garden beds along the way. Fill a wheelbarrow, walk it over to a garden bed, tip, then repeat. Every five loads or so I stop to rake the few piles flat across the garden beds and around the buses. It’s my exercise, a chore I relish. A moveable feast of a compost pile.

Just a few wheelbarrows left to spread among my garden beds.

Just a few wheelbarrows left to spread among my garden beds.

Dr. Chalker-Scott’s research findings about compost can be found on a wonderfully informative website produced by the Washington State University Extension called Horticultural Myths, at http://puyallup.wsu.edu/lcs/. More of her findings may be found at The Garden Professors blog, http://gardenprofessors.com/.

My Pile: ‘The Best Fertilizer in the World’

Posted by

1

I’m blessed to live within easy reach of the ocean, and it’s to the beach I go to bulk up on the greenest of green for my pile, seaweed.

This is not a new idea in these parts, as I discovered through an exhibit held some years back at the local historical society. “A Bunch of Farmers” detailed the area’s agricultural roots, beginning in the 1830s, which over the generations developed richly with the “successful maritime exportation of fish and produce to New York, Boston and beyond. By the Civil War, Westport was the leading onion supplier to the Union army, and onion farmers used nutrient-rich seaweed as fertilizer.”

Onion blight, along with the invention of modern food production and preservation technologies, did away with the farming of onions in the loamy, sandy fields here in coastal southern Connecticut, which gave way to second-growth woodland and tracts of suburban housing, ranging from gilded manor and weekend New York retreat to postwar cape and modern McMansion.

My one-story, two-bedroom cottage was built in the early 1950s and sits squarely in the center of a flat, one-third-acre corner lot of coastal marshland long ago dredged and drained into farm fields for those onions and later filled in to develop as postwar housing.

Driving to work or errands along the narrow, winding road my house sits on, each day I pass by two old onion barns. The smaller was long ago converted into a house; the larger, two-story wood structure tucked into the side of a hill, is still pretty much a barn and now used as what looks like a pool house for the modern home it sits behind.

My home is just a mile or so away from several public beaches strung along the northern shore of Long Island Sound in a collection of rocky coves, sandy beaches and tidal-river marshland. I drive to one of the local public beaches often in the fall, with the dog sniffing sea breezes out the side window and a washtub-size plastic bucket in the back cargo space of my SUV.

My dog and I both prefer low tide — him for chasing a tennis ball over the tidal flats and me for searching out the easiest pickings of washed-up seaweed and salt marsh grass.

Gathering seaweed in the fall at a local beach.

Gathering seaweed in the fall at a local beach.

Depending on the season, the weather and the wind, high tide usually leaves a long scraggly line of flotsam, most of it a motley salad of different kinds of seaweed and scraggly reeds of salt marsh grass turned to hay. The wrack line, they call it.

Today’s catch was good; a recent storm had pushed up a dense patch of detritus along a rock jetty close to the parking lot.

The seaweed is yellow and brown and green and chopped by the waves into small mushy pieces, the edges crinkly like lasagna. The layer I set upon is a half-foot deep and flecked with all kinds of seaborne detritus, a Sargasso Sea at my feet. I turn the plastic tub on its side and scrape the briny mix into the bucket with a three-tined hand hoe.

Caught up in the tidal ebb and flow are dismembered crab legs and carapices of baby horseshoe crabs. Shells of mussels, clams and oysters dot the mix, and in they go, too. The clattering seashells, which slowly break down into their basic components of lime and calcium, offset the acidic mulch of all the leaves in my pile. (I’ve also heard that seashells give tomatoes more flavor, and I flick stray shells from the seashore straight into the vegetable garden. Like tossing a penny into a fountain, I wish for tasty tomatoes next summer.) I always have to separate out a few bits of styrofoam or plastic — a broken fork, a bottle cap, snags of fishing line or deflated mylar shell of a helium party balloon, with string.

I love bringing this bit of the beach back home with me. The bucket smells like part wet swimsuit, part low tide, and all pure summer.

Seaweed gathered from the local beach is a rich stew of ready to rot greens.

The town opens up its beaches to dogs on Oct. 1, and I bet I’ve made 10 trips back and forth since then. It’s always a good day when you are at the beach, and on most visits within an hour or so I can tire the dog out and fill up a keg-sized bucket with 30 or 40 pounds of fresh, ripe seaweed or, just as good, a lighter mix of salt marsh hay. My dog’s in great shape, and so is my pile.

“Seaweed garden nutrients are relatively low in nitrogen and phosphorus,” I read on gardeningknowhow.com, “but contain about 60 other trace elements, as well as fungal and disease preventatives. Using seaweed for compost improves soil consistency and increases water retention in sandy or grainy soils and may be used as a top or side dressing. Composting seaweed speeds up the compost process.”

Erik Hoffner, writing for grist.com, adds that “besides being full of necessary nutrients, [kelp seaweed] also contains growth hormones (auxins, gibberellins, and cytokinins) which are readily taken up by plants and put directly to use.”

“Talk about magic seaweed,” writes noted journalist David Kirby in a fascinating article published in late 2016 on takepart.com, wonderfully titled, “How to Stop Farts From Warming the Planet: Feed Cows Seaweed.”

“A single type of seaweed could cut greenhouse gas emissions, fight ocean acidification, removed invasive species, restore fisheries, and help coastal economies around the world,” Kirby writes.

“Researchers in Australia have discovered that the seaweed, Asparagopsis taxiformis, when mixed with livestock feed in small amounts, reduced methane emissions from sheep by up to 80 percent.”

All those burps and farts and manure add up to a huge amount of methane — more than 5 percent of all global greenhouse gas emissions, Kirby quotes a researcher, “The total contribution from land transportation is 10 percent, so we’re talking about the equivalent of half of all the vehicles in the world. It’s not a trivial number.”

I worry about the amount of methane, however negligible it may be in the greater scheme of things, my puny pile may fart out. So I take comfort in knowing that the seaweed I stuff into it may also be a solution to a far greater problem. Evidently, the seaweed contains a compound that helps disrupt enzymes used by gut bacteria to produce methane, which has up to 36 times the global warming potential of carbon dioxide.

We may be only just now finding out how basically good seaweed is, in situ and on my pile, but this new reporting makes me appreciate it even more.

Garden writer Eleanor Perenyi, in “Green Thoughts,” her classic account of gardening along the Connecticut coast in Stonington, also sought out seaweed, which required hiring “a man with a pickup truck and the willingness to scramble over wet rocks wielding a pitchfork, not a combination I find every day.”

“The ultimate mulch is, of course, compost and if I had enough of it I would need no other. But one never does have enough—wherefore the salt hay and, increasingly of late, seaweed.”

Perenyi also cites salt hay as “a good source of trace minerals and decomposes without depleting the soil of nitrogen.” Added to my pile it also helps aerate the mixture of other rotting organic material, and any bucket of seaweed I haul home from the beach is usually suffused with the straw of salt marsh grass.

“Like compost [seaweed] is a fertilizer as well as a soil conditioner, one of the oldest known to man. All marine peoples have used it. In seventeenth-century France, royal regulations established the kinds to be gathered and how they were to be used. It has twice the potash content of barnyard manure, making it perfect for beets, potatoes and cabbages, the potash lovers. More than that, it has the power to unlock minerals in the soil; it contains growth-inducing hormones that will increase the yields of tomatoes, corn and peppers. Plants given seaweed are better able to endure a light frost, and some are made more resistant to insect and disease attack. With those remarkable properties (some of which, it is true, have only lately been established by research), and given the high cost of commercial fertilizers and pesticides, you might expect to see the gardening citizenry of both coasts swarming over the rocks and beaches. You don’t, partly because no high-level interest exists to care to tell us.”

Another inspiration for adding seaweed to my pile is The Field, a fine if unsettling film by Jim Sheridan, made from a stage play in 1990 with a stellar cast, starring Richard Harris, John Hurt, a young and menacing Sean Bean and Tom Berenger as the rich, handsome Ugly American. The title role is played, with convincing Irish charm, by an acre or two of lush green pasture enclosed by a rim of ancient stone walls.

Bull, inhabited by Richard Harris, has tended the rented vale his entire life, turning it from barren ground to most productive pasturage, where he raises fresh hay and straw to feed his livestock for market. To Bull, his field is my pile a hundredfold.

The movie begins with Harris and Bean, as his mulish son, collecting heaping strands of giant kelp fronds from a rocky beach, packing the lot into wide-mouth wicker baskets on their backs and schlepping the harvest of seaweed over hill and dale back to their Field.

Their arduous trek plays out wordlessly over the opening titles. Cresting the last slope between the sea and the field, Harris plops down his basket. Gazing over the valley to his field, he says to his son, “God made the world, and seaweed make that Field, boy.”
the-field-richard-harris
“It’s the best fertilizer in the world,” Harris adds as they dump their wicker backpacks atop a pile of seaweed-infused compost, an Irish version of my pile.

It’s a tragic movie, and near the end, old “Bull” Harris tells the American, Berenger, who wants to buy the land out from under him, “It’s my field. It’s my child. I nursed it, I nourished it, I saw to its every want…”

If not to the same morbid end, I feel the same way about my pile.

Seaweed adds a rich mix of nutrients and minerals to my pile.

Seaweed adds a rich mix of nutrients and minerals to my pile.