Tree Bog Toilet: Top 5 reasons to love it

I’ve read the permies posts about tree bogs and bucket composting toilets and there are some good arguments in favour of using buckets. That said, I’m still a big fan of tree bog toilets for my situation and here’s my top 5 reasons why:

5) SOIL BUILDING MACHINE. What initially inspired me to go with a tree bog for our property was a video of of a permaculture designer (who's name I forget - post it if you know) working on an island with very shallow and rocky soils (volcanic perhaps). He used the toilet system from an elementary school as an "ENGINE" to improve the soil. After some time he was able to grow fruit trees and create a food forest in what had been a desolate patch of the island. I loved this idea of a soil building ENGINE so I positioned my tree bog to reinvigorate what was essentially a dead patch of dry, shallow and rocky soil. The results have been obvious so far. Look at the dramatic different between these hops plants on my property: https://www.youtube.com/watch?v=NzFU_pqDIZ8

4) WILD LIFE HAVEN. My tree bog site was too shallow and dry to plant the nutrient hungry willow that typically surrounds tree bogs. Instead I planted a diverse array of flowers and food plants for wild life. I put in Jerusalem artichokes as heavy feeders in place of willow and complemented them with bee balm, black cohosh, hostas, hops, black elderberry, eastern white cedar, ditch lilies, lovage, walking onions, comfrey and more. Check it out in the hops video: https://www.youtube.com/watch?v=NzFU_pqDIZ8. The garden is still young but already I’ve seen tonnes of lady bugs, bees and a humming bird sipping from the comfrey. I even had to reinforce the chicken wire cage with a salvaged chain link fence to protect the tee bog from the local porcupine that liked the structure a little too much and was gnawing it up like a beaver on a shoreline tree.

3) NO HOLE REQUIRED. The same can be said of bucket systems but no hole is required to be dug like for an outhouse. My tree bog is on rocky shallow soil where I’d have no chance of digging any sizeable hole without dynamite. In Canada, some hiking trail systems, like the famous West Coast Trail, take advantage of it. Check out this “Cadillac”:
https://www.youtube.com/watch?v=Se3FhXVHtls&list=PL1X7GCKG2ZvEInLcyxi29eBRY4tRLEOXU&index=3. Doesn’t hurt that they can make use of locally abundant pine needles for carbon mulch in a remote situation either.

2) NO SMELL. My tree bog has virtually no smell. The only time that I got a light whiff of detritus was when I crawled under the stairs to paint. It totally confused me because the tree bog had never smelled before and I forgot that I was inches from a decomposing pile of excrement. Better than any outhouse I’ve ever used!

1) LOW MAINTENANCE. The #1 reason that I love tree bogs is that they are super low maintenance once built. We use ours at our property when we visit regularly but that’s not 365 by any means. So the rate of decomposition easily surpasses the rate of deposits which means there is plenty of room and it will never need to emptied. No poop handling required! We add saw dust with each use and sweep the floor occasionally. Twice in the last 3 years I’ve collected the county’s grass cutting on our section of the roadway and added them for extra carbon. That’s it and that’s why I love our tree bog!

What do you think? Ask me anything!

Ottawa Tinkerer

ps - Please post if you think you know the video of the permaculture instructor that I was talking about… he wasn’t Geoff Lawton and I’m 95% sure that the Island wasn’t Tuvalu.

thanks Steve. Do you think you could explain how that works? The only tree bogs I've seen (online) are tropical ones that use bananas and they're quite different in design to what you are showing and linking to. Will that eventually fill up? What will you do then?

Looks really interesting. I wonder if you could root some willow cuttings around it now it's been in use?

Hi Rose, I thought a picture might save me a thousand words so I made this diagram of how it works. Please let me know if anything is still unclear.

As long as we don't overfill it by depositing faster than it can compost, I don't expect that we'll ever have to empty it. There's a Woodlanstv video where they alternate between two tree bogs at a public site. Here's the link: https://www.youtube.com/watch?v=53jtstTaA20&index=2&list=PL1X7GCKG2ZvEInLcyxi29eBRY4tRLEOXU. Again with our limited use of it at a weekend property, I don't think that we'll get there.

Galadriel Freden wrote:Looks really interesting. I wonder if you could root some willow cuttings around it now it's been in use?

Galadriel, that's a great thought! With the extra run off from the roof and more fertile soil I bet that some willow might now grow. Maybe I'll try it in Spring.

Thanks, good diagram.

Seeing the last video I find myself going what a waste of a good resource (being a humanure composter), but I can see how you could plant something useful like willow to benefit from the fertiliser.

Did you put in a bottom layer of absorbant material? Not concerned about liquid travelling down?

Thank for your reply Rose. If food production is your main goal (and a worthy goal it is!) then I could see how you might see this system as wasteful. Instead of a waste, I see it as producing different yields.

My tree bog yields shade, habitat for bats or birds, chop and drop mulch, nectar and pollen for pollinators, soil bacteria and soil. These products can all rejuvenate the nearly dead patch that I started with. A patch that barely supported hardy jack pine or recalcitrant euro buckthorn. Now my hops is growing better than ever and I can chop and drop my pollinator fodder to spread beyond the tree bog. That will improve the surrounding soil to the point I hope that I can plant trees that wouldn’t have grown there previously, some of which I will be food producing trees.

So in an indirect way, I guess that humanure systems and my tree bog do yield the same thing… soil. You use the soil directly to produce food and I will use mine indirectly to produce it. Maybe one day I’ll give humanure a go but for the time being this tree bog is working well to deal with semi regular deposits while repairing an old worn patch of land


To answer your other question, I haven’t observed any leakage; the tree bog basically sits on a cubic metre of straw and wood chips so I think that liquids are absorbed. Also the moat around the outside prevents surface run off from sweeping much away.

thanks for the explanation, it looks like good design, and very useful for those not able or wanting to do Humanure.

By wasteful, I wasn't meaning what kinds of plants and outputs, I was meaning the fact that the tree bog stays in one place indefinitely so there is a hyper-accumulation of nutrients in one place rather than spreading that over a larger piece of land. But it's not really a criticism because I can think of situations where a tree bog would be more useful and appropriate than a bucket and bin system.

Thanks for taking the time to share your project, I'm learning from this. Would love to see an update in a year or so.

Thanks for the discussion Rose, it's helped me think about this from different angles. I'll try to post an update in year's time or so.

Steve Simons wrote:

5) SOIL BUILDING MACHINE.  What initially inspired me to go with a tree bog for our property was a video of of a permaculture designer (who's name I forget - post it if you know) working on an island with very shallow and rocky soils (volcanic perhaps).  He used the toilet system from an elementary school as an "ENGINE" to improve the soil.  After some time he was able to grow fruit trees and create a food forest in what had been a desolate patch of the island.



ps - Please post if you think you know the video of the permaculture instructor that I was talking about… he wasn’t Geoff Lawton and I’m 95% sure that the Island wasn’t Tuvalu.

I think there's a pretty good chance you're referring to this presentation by Toby Hemenway, and specifically what he shares starting at around 47:12.

Steve, any updates on the project? I'm curious to learn more.

This is a nice implementation.
The point about hyperacumulating nutrients in one place makes me think the problem is a solution.
Fast growing nutrient accumulating plants like comfrey can turn the poo into portable and pathogen free green manure.
It's an extra step,  but you get perfect plant food and you never have to handle poop.

This seems like a great option, with many benefits. I’m trying to implement a system on my property, which is used by a wide spectrum of folks-some not yet accustomed to pooping without the aid of 6 liters of drinking water.
There are a couple of main questions I’m trying to figure out, hopefully someone here might know.

1: What happens to the paper? In the pile with all the other waste? A separate bin to be burned or disposed of elsewhere? Do I need to make sure a particular type of paper is used? Or can someone bring up their own favorite brand?

2: I have black bear on my property. They seem to get into anything that smells good (or bad). I know one of the benefits is the lack of smell, but I find it hard to imagine that a bear wouldn’t be able to pick up on it. My fear is that I put the work into this nice structure/system just to have it dig out or destroyed by a scavenging bear late in the season. Anyone have experience with dealing with bear? Either with a tree bog or traditional humanure compost pile?

Leaf, according to this woodland toilets or tree bogs video by WoodlandsTV, toilet paper also goes down into the toilet.  The treebog information sheet from Biological Design also suggests that under heavy usage woodchips, shredded newspaper, or straw/leaves should be added weekly.  While I haven't come across any information about bears, the same info sheet talks about needing to protect from badgers.

I think that WoodlandsTV is in the UK and they don't have bears, so they would explain why they don't mention it. We have bears on our property but the only thing that they have ever tried to mess with was our water tank. Around here, they really avoid people.

I'm thinking that this is a good idea for the areas that I have people camp, so the usage would be quite limited. Because of that I don't think that I will really need to add additional trees.