Pinecones for material for small scale biochar?

Hello Amelia,
Welcome to permies.  I think that urine is a good inoculant. There are many others, and there are many threads about inoculants in this forum.

Here is a discussion of using bought charcoal from a store:
https://permies.com/t/150787/Biochar-charcoal-bought-store

John S
PDX OR

I have just used a lot of pine cones in my last two biochars and it worked really well.  They are easy to collect and ready to burn.  The only caveat I have is, don't add them at the end, because they seem to off gas a bit more than other wood and they still need to be charred like other wood.  They work like kindling, so you can use them with paper or cardboard to get the fire really roaring.  I put them at the top of my TLUD.
John S
PDX OR

I forgot to mention.  Japanese knotweed should be a great one to make biochar out of.  My only caveat is to make sure that you aren't accidentally creating more of the plants.  It can root from a small piece of the plant.  I live in the PNWet, so I wouldn't do that in between October and April.  However, it tends to be very dry here from about May to September, so I would chop it then, collect every part of it, dry it out, and then yes, make biochar out of it.  Did you know that Japanese knotweed is the primary commercial source of resveratrol for the supplement industry? I 'm  almost 60, so I make medicine out of the plant as I"m killing it. Resveratrol is the medicine in red wine that helped create the French paradox-why are they so healthy if they eat goose liver and drink wine all day? I just put the chopped up orange roots into glycerin to make a glycerite-extract.  Improves my health and saves me money!

John S
PDX OR

Exactly.

I'm trying the pinecone char.
Need to pyrolysis longer. Only charged outside cones, next time tin is going into a campfire on it's side so I can see when the flames die.

Those are Douglas fir cones.  I don't use the retorts like that because the volume of char generated is so small. It would take too long to make a difference digging it into my suburban yard,  but it might be a good fit for someone else's project.
John S
PDX OR

Yes they are Doug fir I have a lot so I thought they would be good proof of concept fule. Unfortunately the pocket rocket was too hard to tell when they were done or not hot enough to work for any but the outside layer. But practice makes perfect, when I get better at getting a complete burn I'll try to scale up.
So tried the campfire heat today. I could hear the gas rushing out of the pinhole in the lid. When it stopped I tried rolling the can to stir the insides and the lid popped off. Given the flames dancing on the cones still inside I don't think it was done yet. More experiments needed.

Chris Kott wrote:

Ellendra Nauriel wrote:

Douglas Alpenstock wrote:I see no reason why fir cones would not cook into decent char. Actually there isn't much dry veggie material that wouldn't,

I'll second this. The majority of the char I make is from non-woody material. Crop debris such as bean shells, sunflower shells, corn stalks, etc, all make decent char. If you have a dog or cat, their poo can be made into char as well, eliminating both the smell and anything infectious that might be lurking inside.

Try the cones and let us know!

Ellendra, that's genius.

I know about pyrolysing toilets for humans, and if I have a glut of heat energy, I would go that route for human feces, simply for the ability to cook out and break down any contaminants, including but not limited to microplastics and pharmaceutical residues.

But the real genius comes when you apply that to cat owners. I simultaneously hate cats and love the two I've had in my life. Cat feces is the bane of my existence, speaking as a former cat owner and gardener; it was one of the driving factors in our choice of Flemish Giant Rabbit over a Russian Blue cross cat (I am allergic, but least allergic to those). The worms appreciate the decision, as we use a product that is raw, unbleached waste product from the paper industry as bedding.

I think that I will remember this if we should ever have cats, and probably for the dogs as well (definitely having dogs).

Jay, I think that pinecones will work fine. They are almost a matrix for something else, though, something that may be too dense to char as a pile. If you had sawdust, for instance, or more shavings, you could stand a bunch of the cones upright in your pan and sift the little bits over them so that the open scales (I am assuming they're open) fill. That would let you get more char per batch, and would make it easier to restrict oxygen by eliminating much of the open air space.

-CK

Chris & Ellendra, are you saying you burn the feces? Doesn't it have to dry out well before you can get it to burn hot?  In the mean time how do you store it to keep it from smelling?  Dog feces dries out quick as it is left on top of ground but cat naturally is buried and also human in keeping with "nature".

I like the idea of using pinecones and crushing to remove the air spaces is a great idea maybe driving truck tires over it to make it quick work.  I have burnt old wormy acorns and all sorts of nut shells in my woodstove and they seem to burn well even turning into char sometimes. The acorns usually hold their shape so need to be crushed.  It might be the amount of fat inherent in them. I don't know what that does to the chimney flue in terms of making more creosote or not due to the fats.  Anyone have any scientific insight on this?

Last winter wasn't a great one for biochar as we had a lot of above average temperatures and my fire tender was badly distracted by crises.

However, this is what I did:
1. Recall that I use restaurant warming trays to make biochar in our wood-stove.
2. I put a layer of sawdust from my friend's saw mill in the the bottom of the pan. Sawdust has the tendency to mat down and not burn thoroughly according to what I read somewhere (maybe even here?). So I did try to "gently place" it, rather than pack it!
3. Then I put a layer of pinecones with gaps in between.
4. Then I sprinkled more sawdust over the pinecones until they were covered by about 1/4 inch.
5. I repeated steps 2, 3 and 4, but this time tried to have room for closer to 1/2 inch of sawdust on top.

This "layer cake" went into the wood-stove. I should have taken pictures, but the short answer is that the sawdust completely charred. The scales of the pinecones broke apart easily with just the light weight tool I use for stirring the char with. The core was a little tougher and was generally left larger.

If your goal is just soil health, biochar that's really small is recommended. However, I have read that if you have heavy clay soil, some bigger bits of biochar help to lighten the soil. Thus I am not concerned about the core  being a slightly larger piece, or even the scales being full size, but Doug Fir Cone Scales are quite small and thin to begin with.

I do think that the cones were a good addition because of the way it seemed to prevent the sawdust from packing down. One lot we made with just sawdust, had areas that had not fully burned despite it being in the fire what we thought should have been long enough. I will definitely do more this coming winter, although I would really like to find a good way to make larger quantities safely. Our fire risk at the moment is labeled "extreme", but by the time it isn't, it's usually pouring rain. I think step one would be to find efficient ways to get material dry during the summer, but not have the humidity alone, get it damp before it's safe to have fires.

Great technique, Jay.
For those of us that also live in the PNWet, winter is a very difficult time to make biochar outdoors.  I don't have a wood stove, but for those who do, this could be a great process for making it in the winter.  I just don't make biochar in the winter.  

John S
PDX OR