Eight years ago, panting heavily in the humid summer air, I carried a pair of orange work buckets full of wood chips up a leafy hill in rural North Carolina. Although these were ordinary wood chips, the pilot study I’d come to observe was planning to put them to an extraordinary use: composting a dead human being into soil.

The deceased gentleman I saw that day, lying on the forest floor in dappled sunlight, had donated his body to science in order to be useful to society after death. Now that gift and the study, by the Forensic Osteology Research Station of Western Carolina University, have borne fruit. With human composting technology, our dead have the chance to become nutrient-rich soil that can be used to plant trees and regrow forests.

As of today, five states — Washington, Oregon, Vermont, Colorado and, most recently, California — have either legalized or set a date for legalizing human composting as a means of disposition after death. In New York, one such bill has passed the Assembly and Senate. It now awaits Gov. Kathy Hochul’s signature.

Human composting — or, as it’s sometimes referred to, natural organic reduction — fulfills many people’s desire to nurture the earth after dying. It owes much of its present form to Katrina Spade, a Washington-based designer and entrepreneur who told me that her goal is to see “composting overtake cremation as the default American death care in the next couple of decades.”

In 2015, as an architecture student, Ms. Spade started a nonprofit called the Urban Death Project, envisioning strolling past the brownstones of Brooklyn and coming upon a municipal human composting facility. There, passersby would reflect on mortality and the cycle of life, feeling a sense of connection to the earth, past and future — the way urban cemeteries like Green-Wood were designed to make repose in death a harmonious part of city life.

The details vary, but human composting generally works like this:

Air and

moisture

Air and

moisture

Biofiltered

air

Biofiltered

air

Bone fragments larger than one centimeter

Cremulator

Non-organic material like hip replacements

Bone fragments larger than one centimeter

Cremulator

Non-organic material like hip replacements

Bone fragments larger than one centimeter

Cremulator

Non-organic material like hip replacements

Bone fragments larger than one centimeter

Cremulator

Non-organic material like hip replacements

1 cubic

yard of soil

1 cubic

yard of soil

The process takes place inside a cylindrical vessel — they remind me of a Japanese capsule hotel for the dead.

A bed is made of plant materials like straw, brown wood chips, sawdust and alfalfa.

The body is then wrapped in a cotton shroud and laid in place.

During the ceremony, loved ones can add flowers and other meaningful organic materials.

Air (and in some cases, moisture) is pumped into the vessel to ensure that conditions are ideal for decomposition.

The microbes naturally found in the body and plant material will begin to break everything down.

Temperature and airflow are monitored and controlled, and the vessel is intermittently rotated for aeration.

Fragrant gases such as cadaverine and putrescine are treated with a biofilter before being released.

After six to eight weeks, the body has undergone a complete transformation.

Near the end, all that is left are bone fragments, any medical implants (like artificial hips) and nutrient-rich soil.

Remaining bones are ground into powder in a cremulator, a machine commonly used after cremation, before being returned to the soil to further break down.

Medical implants are hand-sifted out and recycled. The soil is also tested for any harmful chemicals such as lead, mercury, arsenic and even fecal coliform.

The soil is left to dry out and cure. Once the process is complete, there will be approximately one cubic yard of new soil created from the mixture of what was, at the start, human remains and plant matter.

This special earth can then be scattered in a cemetery, placed in a grave or given to the family to use as it sees fit. Tanya Marsh, a professor at Wake Forest University and a leader in human remains law, said that in the New York bill the final product is defined as soil, with no restrictions placed on its use.

After working for years in the American funeral industry and founding a nonprofit to promote acceptance and legalization of new green funeral options, I felt the need to warn Ms. Spade that with death, change comes slowly. The new composting process would have to be approved state by state, one by one.

The Urban Death Project is now shuttered. In its place, Ms. Spade founded Recompose, a new for-profit company designed to bring human composting to the public. (She and I have been friends and have advised each other’s work for years but have never had any type of financial relationship. I have no stake in Recompose or any other human composting company.) The business is up and running in Washington, alongside several other new companies like Return Home, Earth Funeral and the Natural Funeral, which serve other states where human composting is legal.

A demonstration of what a service might look like before the composting process begins at Recompose. Will Matsuda for The New York Times

There are environmental and financial reasons this process makes sense for New York. In the city, we’re running out of space for burials. Plots in New York City typically range from $4,500 to $19,000 — and some plots in Manhattan can cost up to $1 million. This price doesn’t include the additional tens of thousands of dollars it typically costs when a funeral home prepares and transports a body for burial.

The usual way to save on these costs has been cremation, which can be available in the $2,500 range. But cremation has drawbacks. The cremation process uses as much fossil fuel per body as a 500-mile car trip. And releases harmful air pollutants like dioxins, mercury and fine particulate matter into the surrounding neighborhoods. Human composting, by Recompose’s reckoning, uses just an eighth of this energy and falls in total price between cremation and conventional burial, at around $7,000. This process also saves around a metric ton of CO₂ for every person composted, compared with conventional burial or cremation.

Human composting is a less carbon-intensive funeral alternative

Average net CO₂ emissions

Human composting

less than 20 kg of CO2

Cremation

233 kg

Burial with a concrete vault

833 kg

Burial with concrete vault and monument

1,252 kg

Human composting

less than 20 kg of CO2

Cremation

233 kg

Burial with a concrete vault

833 kg

Burial with a concrete vault and monument

1,252 kg

Sources: Burial and crematory estimates from Les Services Funéraires, Ville de Paris; human composting estimate from an analysis commissioned by Recompose.

Besides these practical reasons to re-examine our way of dying, there are emotional reasons. We humans value our relationship with the planet we live on. It’s natural to want to give something back and, in a deep way, to return to the elements — to return our atoms to nature.

There are still a few opponents of this future: the New York State Catholic Conference stated that the process “is more appropriate for vegetable trimmings and eggshells than for human bodies.” I hope these holdouts will come to understand the profound meaning this new form of repose gives to the dying and their families. The process was so important to one Brooklynite, Michelle Miller, that when her mother died, Ms. Miller had her body transported to Seattle to be composted. “It was moving, quiet and meaningful,” she said. After the process, “members of my family called to say the experience was healing for them in ways they had not expected.”

An array of Recompose’s human composting vessels. Will Matsuda for The New York Times

The passageway between the room where services are held and the room where composting occurs. Will Matsuda for The New York Times

Sean Ovens was an officer in the Tacoma, Wash., police department and an instructor at the local police academy. After he took his own life in July, his mother, Roberta Vollendorff, had his body composted at Return Home and brought the soil from his remains to a Sitka spruce tree on her property. “Not everybody has as much land as I do, but almost everybody has plants that they can go to,” she said, adding, “I can walk out to the tree that I’ve walked out to all these years, and my son is there. It’s so comforting.”

There are also those who fear their own eventual decay. It has been a century since America’s dead have regularly returned to the organic life cycle. The American funeral industry has promoted the idea that the “dignified” dead body should be preserved by formaldehyde embalming, placed in a sealed casket and lowered into a heavy concrete vault under the ground. This is a valid choice, but it treats the dead as something to be vigilantly protected. Human composting reframes the dead body: not something to be protected from nature and the elements but something meant to return to them. It requires facing the reality of a changing climate and our place in the life cycle — no small existential feat.

Our society continues to search for new rituals and new ways to affirm that we’re all dignified in our mortality, that dust will be dust. We ought to respect everyone’s choices for their dead and realize that no one group can define for the rest what a dignified death might look like.

Morgan Yarborough, a licensed funeral director at Recompose, walks through the woods at Bells Mountain, Wash., where saplings have been planted with soil created by human composting. Will Matsuda for The New York Times

Six years after carrying those wood chips through the North Carolina forest, I visited another forest, in southern Washington. After decades of depletion by logging, this forest had been taken over by a conservation organization with a special mission. A golf cart drove me along a rewilding logging path, up to a field of dark-brown compost. The soil in this compost was once the bodies of 28 humans: now all were one, part of the woods around them. These 28 people chose to donate their soil to help regrow native trees and eventually bring shade to a salmon-spawning stream.

The soil in this field testifies to a group of pioneers who wished, as a last gesture, to help repair some of the damage we’ve done to nature. It’s a gesture everyone in the country should have the legal choice to make and many in New York would like the opportunity to make. If Governor Hochul signs the bill into law, New Yorkers will have the chance to use their loved ones’ soil in any way they find meaningful: scatter, plant a tree, take to a cemetery, fertilize a garden or donate to a conservation organization.

At Recompose in Seattle, Ms. Spade has composted the bodies of over 200 people. Other states are following suit, with new practitioners sprouting up to offer the service to their communities. There is a broad desire in America to expand our death care choices and to align them with our hopes and dreams for a healthy planet. New York can light the way.

Saplings planted with soil from human composting will grow to shade a stream on Bells Mountain, Wash., helping restore the salmon habitat on previously logged land. Will Matsuda for The New York Times

Correction: Dec. 7, 2022
An earlier version of a picture caption with this article misidentified the organization that planted saplings in Bells Mountain, Wash., in soil created by human composting. It was Remember Land, not Recompose.