I think that I shall never see
A poem lovely as a tree.
A tree whose hungry mouth is prest
Against the earth’s sweet flowing breast;
A tree that looks at God all day,
And lifts her leafy arms to pray;
A tree that may in summer wear
A nest of robins in her hair;
Upon whose bosom snow has lain;
Who intimately lives with rain.
Poems are made by fools like me,
But only God can make a tree.
Joyce Kilmer (his given name was Albert Joyce Kilmer so many mistakenly think he was a she) wrote “Trees” in 1913. The poem is often scoffed at for being overly simplistic. But “Trees” remains memorable, unlike other more pretentious works. People love trees. Some even want to become a tree after they die.
So it’s not surprising that people are going bonkers over a fairly recent alternative to traditional burial called a Bios Urn. At least a dozen people have forwarded me articles about it, so I knew I had to see what they were all about.
The Bios Urn is touted as an environmentally and economically friendly way to dispose of your ashes, which supposedly help fertilize a seed as it becomes a tree. Picture courtesy of the Bios Urn web site. Co-designer Martin Azua told Discovery News that he would “like to be buried in a Bios Urn in a forest in the Basque country [of Spain].”
Back in 1999, two Spanish designers named Gerard Moline and Martin Azua owned a studio called Estudimoline. Together, they patented a biodegradable urn with a plant seed inside designed to place beloved pets who had died back into the life cycle. From there came the idea of the Bios Urn for humans.
A big selling point of the Bios Urn is that you can use your cremains (the ashes from cremation) to nourish a tree seed. In other words, you can literally become a tree that will grow for years after your death. Instead of taking up space in a cemetery, you can become part of a forest. The idea is very appealing to environmentally conscious post-Baby Boomers that want to do things differently than their parents did.
Before I explain how the Bios Urn works, let me clarify that I am in no way a scientist or a horticulturist of any kind. I am simply sharing with you what I discovered when I searched a bit beyond the Bios Urn web site.
The urn itself is made up of 100 percent biodegradable materials such as coconut shell, compacted peat and cellulose. So nothing is left behind after it breaks down. The top section contains the seed of whatever tree you’ve chosen (eight varieties are available) or you can supply a seed of your own.
The separate bottom part is where you pour the ashes. I’m not sure just how much is required but since a human body usually becomes between four to six pounds of ashes after cremation, there’s going to be some left over.
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This diagram gives you an idea of how the Bios Urn works. The top half contains the tree seed and soil while the bottom half contains the cremains (or cremated ashes) of the deceased. The roots eventually grow through the bottom half and into the ashes. Photo courtesy of Jebiga.com.
Here’s how it works. You place some soil from where you intend to plant the urn in the top half along with the tree seed. You then pour the ashes into the bottom half. The two parts are secured together, which can then be planted. Bios Urns’ website recommends that the urn be planted five centimeters (about two inches) from the surface.
The Bios Urns website says the urn requires the same care as a normal tree: water, sunlight and a good temperature. This can vary according to the kind of tree you choose so they recommend that you read up on whether or not it is a good variety to plant in your specific area.
The Bios Urn tree seed eventually grows roots and breaks into the lower section where the ashes are, which are supposed to serve as fertilizer. Voila, you’re now part of a tree!
While one advertised benefit of the Bios Urn is that you can plant it almost anywhere, I don’t know if cemeteries are too keen on them. You’d have to get permission to plant it and they would be the ones in charge of maintaining it for you. Since most traditional cemeteries are very focused on maintaining easy grass mowing, they may not allow it. However, the new “green cemeteries” would likely be happy to handle that request.
One tree variety that Bios Urns sells is the ginkgo. Considering that they have a reputation for emitting a strong unpleasant odor, I don’t think that’s a legacy I’d want to leave behind.
My thoughts on the long-term implications go into overdrive when I consider this. If my Aunt Harriet wants to be buried in her back yard, what’s going to happen if the property is eventually sold? Do you dig her, I mean, the tree up and take it somewhere else? If Aunt Harriet wants to be buried in a park, you’d probably have to get permission. If you own family land, you could plant the urn there. But what happens years from now after you die and your heir chooses to sell the landt? What do you do if the tree dies?
I did read about proposed BiosParks where you could plant your Bios Urn and monitor it via GoogleEarth. But I couldn’t find any information about whether or not that ever became reality.
What I wanted to find out was if the concept of using human cremains as tree fertilizer is scientifically valid. Here’s what I came up with.
After a body is cremated, the resulting ashes and bone fragments are left to cool. A device then pulverizes the bone fragments into a fine dust with a consistency similar to sand. There’s nothing organic left behind.
What exactly are cremains made up of? The graphic below breaks down just that. Almost half of human ashes are made up of phosphate and a fourth of it is calcium.
Human cremains are made up of a mixture of different chemicals, but most of it is phosphate with calcium coming in second. Graphic courtesy of VillageMemorial.com.
Some gardeners believe that calcium phosphate makes an excellent fertilizer. But I’ve also read that when produced at higher temperatures (like fire from a crematorium), it can become insoluble and not very useful as a fertilizer.
A company called Let Your Love Grow (LYLG) has done extensive research that shows that cremains have a very high pH level that hinders their ability to release any helpful nutrients. Also, cremated ashes contain sodium in amounts that range from 200 to 2000 times what plant life can tolerate.
LYLG published a photo that shows how 16 months after burial, a biodegradable urn has completely dissolved (I have no idea if this is a Bios Urn). The ashes are left in concentration and may remain that way for years. Plant roots will inevitably turn away from this clump of salty rock.
To remedy that, LYLG sells a special mixture that, when added to regular soil and cremains, balances out the high pH level/sodium. This enables people to then bury their loves one’s cremains without harming the soil or any surrounding plant life.
This picture from Let Your Love Grow shows the ashes left behind from a biodegradable urn some 16 months after burial in the ground. They contend that human ashes do not provide adequate fertilization to support growing trees.
Discovery News’ article about Bios Urn points out that “plants that like acidic soil might find that the ashes raise the pH of the soil too much for comfort.”
I’m not enough of a scientist to say whether or not these concerns are valid. Perhaps there’s something in the Bios Urn itself that makes the growth process of the roots into the ashes work well with the local soil. The Bios Urns website is vague on those horticultural particulars.
Bios Urn can be purchased directly from their website for about $145 with shipping costs being variable. The cost is the same for Bios Urns for pets. Some retailers sell them as well. Bios Urns’ website claims that over 7,000 have been sold.
Puerto Rican-based Spiritree sells a similar urn. Their cost is a bit higher at $225 and the process is a little different in how the ashes are introduced to the roots. Another option on the horizon is the actual composting of human remains, but current state laws forbid it. I plan on writing about that soon.
I’m sure many people will continue to be enamored with the symbolic idea of becoming a tree. Me? I don’t think so. Because this is the mental picture I get when I think about it. And that’s one I don’t think I can live (or die) with.
Adventures in Cemetery Hopping 
Thank you for mentioning Let Your Love Grow in your blog and I would like to clarify a couple of points, if I may.
Any and all of the information found on our website is not alleged, it is backed by scientific research.
LYLG was developed and designed to address the issue of cremated remains effects on the environment. We have studied cremated remains thoroughly for the past six years. As a licensed funeral director and embalmer in Missouri since 1979, I too thought that cremated remains were “ashes”.
The main misconception of cremation ash is that they are ashes when in fact there are no ashes in cremation ash. Cremation ashes are bones that have been processed into fine particles following cremation. Cremation is the reduction of a body by fire, leaving only the skeletal remains. Cremation ashes are not unlike fossils. The cremation process stops natural degradation by removing all bacteria from the bone. The bone becomes stable and does not change state when scattered on earth or at sea. This is the reason why so many public areas and many private areas do not want cremation ashes scattered on their grounds – they will remain visible or at least present. People scatter cremation ashes with best intentions believing they are helping return their loved one back to nature and benefiting plant life, when in fact, this is not true.
Many consumers, crematories and funeral professionals are not aware that cremation ashes are toxic to the environment. Cremation ash has an extremely high pH which prevent the natural agricultural nutrients within the bone from becoming active in the environment and enhancing plant life. In addition, cremation ash also contain sodium in amounts that range from 200 to 2000 times what plant life can tolerate. We know the detrimental effects of sodium on the human body. Plant life is no different.
LYLG has built a team of experts that include a world renown forensic entomologist, a world renown forensic soil scientist, a forensic anthropologist, a plant and soil scientist, a LEED certified landscape architect and a sustainable urban planner. All of these team members have participated in discovering what cremated remains are and the negative impact they have on the environment.
The graph that you display in your blog is somewhat different than that from our extensive research. The three main components of cremated remains are Calcium, Phosphorous and Sodium, along with many other natural agricultural nutrients. However, the nutrients are locked inside the bone fragments because of the extremely high pH and are not plant life available. Any amount of sodium is harmful to plant life. Some plants are “salt” tolerant while other are not. The range that we quote is from our data, backed by our plant and soil scientist. Cremated remains have anywhere from 200 to 2000 times the amount of sodium any plant life can tolerate, especially in concentration.
Biodegradable urns do what they say, they decompose but expose the harmful effects of concentrated cremated remains. The image you show from our website of the mass of bone was from a test we did using our biodegradable containers. I filled one with a 50/50 mix of cremated remains and LYLG and one with an equal amount of cremated remains. The image is of the cremated remains without being mixed. The one mixed left behind no bone fragment and root systems have filled in where it was buried. The clump of bone is still present, three years later.
Let Your Love Grow does what soil and potting are not capable of doing, lower the pH and assist in diluting the toxic level of sodium while unlocking the nutrients and allowing them to become active in the environment. Once the nutrients are released, they will attach to any root system, such as grass, tree, shrub, flower or weeds. Let Your Love Grow is not plant specific.
LYLG was not developed to be another urn but a solution for cremation. LYLG is designed for families that may have experienced a recent cremation or one from years past. The bone is stable and will not change state, especially sitting in someone’s closet or basement. We have many satisfied families that create the perfect remembrance planting or scattering. We have even experienced families co-mingling cremated remains of loved ones and their pets. Your comment at the end of your blog is not an uncommon one that we hear. Not everyone wants to be a tree.
The public is not aware that pet crematories are responsible to dispose of the massive amounts of cremated remains from communal cremations – where the pet parents do not want the “ashes” back. The majority of crematories dispose of the excessive amount of cremated remains by sending them to a landfill or scatter them. The ones that scatter them have noticed the grasses and surrounding plant life was becoming stressed and didn’t know why and had to constantly find different areas to scatter or stock pile the cremated remains. LYLG has a large clientele of pet crematories that use our special bulk product to address this issue. Now crematories can mix the massive amount of communal remains with LYLG and let sit for some time and then scatter nothing but organic matter safely over landscape, grasses or fields. One customer even makes butterfly gardens to nurture the declining population while providing a place of remembrance for the pet parents.
Recently, LYLG was endorsed by the Auckland, New Zealand Council to assist in better managing their cemeteries. The majority of cemeteries throughout New Zealand are managed by the councils. Much debate has taken place between families that wanted to scatter their loved one’s ashes and the council not allowing any more scattering because, in their words, “the ashes are turning up the toes of our roses”. The council brought in LYLG to address this issue and assist the families in creating that memorable experience of scattering and at the same time enhance the grounds of the cemeteries.
In simple terms, cremation stops the natural degradation of bone. LYLG jump starts Mother Nature, allowing the good, natural agricultural nutrients to be returned the earth in a safe and responsible manner.
Thank you,
Bob Jenkins
President and Co-founder
Let Your Love Grow
Hi, Bob! Thank you for your thorough and enlightening response. As I said in my blog, I am in no way a scientist so a lot of what’s involved with “cremains” and the Bios Urn is not entirely clear to me. Your explanation was very helpful.
Do you have a graph I could use for this post to replace the one I have? I would love to be able to share that with my readers so they, too, can get a better grasp of what elements are in the cremains.
I do hope you know I appreciate the fine work you all are doing because I honestly think people have no idea what an impact scattering ashes (or planting them with a tree seed) can have. I know I didn’t before I found your site. Keep up the good work!
Traci
Do you happen to know if it would be alright to use the poem “Trees” in a book I’m self-publishing about getting out in nature where you can have a conversation with God. I’m not expecting to make money on the book, but I think it’s a message many would find helpful.
Hi, Darlene! I’m not positive but I would think you would have to get permission. However, I found this web site that might be helpful to you: https://www.janefriedman.com/permissions-and-fair-use/.
Thanks, I’ll take a look at the link.