Biochar

[Linda Poole]

Civil Eats focuses on the potentials of biochar in this article by Lisa Held.

Farming with this amendment isn’t a climate silver bullet, but it could make more soil a carbon sponge.

It should be a relatively easy sell, as a growing body of research suggests that biochar might just be the most versatile soil health tool available—and an important climate solution. Biochar particles are incredibly porous, creating nooks and crannies that hold onto excess nutrients, water, and microbes. Adding them to fields can reduce nitrogen and phosphorous runoff that pollutes waterways, help soil retain moisture in drought-stricken areas, and stimulate microbial activity. Most importantly, biochar is one of the most stable, long-lasting forms of carbon available. In the right conditions, it can last hundreds—and even thousands—of years, potentially holding on to significant amounts of carbon dioxide that would otherwise end up in the atmosphere.

The Tigercat 6050 Carbonator. (Photo courtesy of Tigercat)
“The evidence is very strong that it’s the best approach [to carbon sequestration],” said Chuck Hassebrook, head of the National Center for Appropriate Technology’s (NCAT) Biochar Policy Project. “But it’s not something we can turn around and do tomorrow at scale. We don’t have the biochar production facilities, and there are knowledge gaps that we need to fill.”

 

[John Steitz]

Civil Eats focuses on the potentials of biochar in this article by Lisa Held.

Very interesting! I hadn't paid much attention to biochar until very recently. Expensive gimmick ?or worthwhile tool? is my question. Being located where we are NW Montana, after reading this article, pushes my interest further.

 

[JustinM]

Where there's a lot of wood waste that's readily available, I can see where making biochar would be a far better use of the wood compared to just burning a pile to get rid of it. However, because there aren't forests everywhere leads me to believe that this is something that will really only be applicable wherever there are forests. In the Great Plains for instance, this option may not hold much relevance as transportation costs would certainly increase the cost of biochar.

Another interesting benefit of biochar is in feeding it to ruminant animals as discussed in Dale Strickler's book, The Drought Resilient Farm. Evidently biochar in the rumen absorbs much of the enteric methane emissions. Pretty interesting!

 

[Mike Thayer]

can biochar be used in making compost using Johnson-Su bioreactor?

 

[JustinM]

That's a good question Mike. Honestly, I don't know because I haven't heard of anyone doing it.

As I think about the bioreactor process, what goes into it, and the different ways the finished compost can be applied, it seems that biochar would best be mixed with the finished compost IF the compost was going to be applied in its solid form. In other words, I don't think it would be a helpful addition to the raw materials that go into the bioreactor unless the compost was going to be applied in its solid form. But that's my guess at this point.

According to everything I've seen via the internet, the best way to affect the most acres with a single batch of compost made from the bioreactor is by applying the finished compost as a liquid (tea) rather than as solid. This way 700 pounds of finished compost can treat up to 350 acres at 2 pounds of compost per acre. Because the application of a liquid through a sprayer or irrigation system nozzle would require removing all the solids (including biochar) so you don't plug up nozzles, the biochar would be screened out and wouldn't make it onto the field. This would negate any benefits from adding biochar in such an application.

At least that's my two-cent opinion until someone can show otherwise.

 

[JustinM]

After posting the above reply, I realized I needed to slightly amend the following sentence as it might cause some confusion:

"In other words, I don't think it would be a helpful addition to the raw materials that go into the bioreactor unless the compost was going to be applied in its solid form."

What the above sentence should say is:

In other words, I don't think it would be a helpful addition to the raw materials that go into the bioreactor.

My apologies for any confusion this might have caused.

 

[Mike Thayer]

Thanks Justin, that makes sense to me.

 

[Mike Thayer]

I just read a report that suggested that it would be beneficial to charge the biochar in compost to allow the microbe community to establish itself in the biochar prior to applying to the soil. (Direct solid application)
Would layering the biochar in the spreader equipment be adequate, or would it have to lay for a few weeks before applying it to the soil?

 

[JustinM]

That makes total sense about charging the biochar with compost. After all, biochar is pretty much just pure carbon which doesn't inherently have any nutrients in it. But it has a tremendous surface area for carrying other things like nutrients and microbes. Did that report say anything about how to combine the biochar with compost? Could the authors be contacted to find out what they did? I'd be very curious. I've had success in the past reaching out to the authors on something to find out more about what they did.

 

[JustinM]

On a different note, were you the one that's in NE CO that's been integrating silvopasture on the shortgrass prairie? I'd love to hear of your experiences in country that's high, dry, and cold. I have a keen interest in silvopasture and would love to see it integrated here on the Snake River Plains of eastern Idaho where I live.

 

[Mike Thayer]

I have been trying with limited success. I have some black locust and mulberry trees that were already in my pasture when I aquired the farm. The black locusts will spread by themselves if the sheep don't strip the leaves off as saplings. I have tried planting lindon, and hackberry trees and some cottonwood. But it has been difficult to keep them watered enough to survive the last several very hot and dry years. I will try again, but be sure to plant the cottonwoods in the bottom of a swale that would have the moisture retained longer. I think I will plant some honey locust (because I can't find any black locust) and bur oak on the higher ground. The key to past success, has been to have a weed barrier around each planting. I think that is even more advantageous than supplemental water. Since I have sheep, and the wool market has collapsed, I may try using tags and drags as a mulch.

 

[Mike Thayer]

Also, at Linda Poole's suggestion, I may try putting snow fence around the individual plantings. It would provide some wind and sun protection in the summer and catch snow in the winter.

 

[JustinM]

Those are great suggestions from Linda. For establishing trees and shrubs in a pasture, or anywhere else for that matter, it's vital that the trees be truly adapted to the climate and not just from a plant hardiness standpoint. Recently I've stumbled upon the work of Ernst Gotsch, a Brazilian who pioneered a concept called Syntropic Agriculture or what is sometimes referred to as Successional Agroforestry. To learn more about this system of agriculture, go here.

In this approach, trees, shrubs, and grasses are established in any environment, even dry regions, without the use of supplemental irrigation. Even water-loving tropical plants like banana have been established in arid Australia where the soil was initially hydrophobic (water repellent). One of the key takeaways from this system is to plant what will grow easily in your environment so that it can help create the microclimate for what you really want to grow. Here's a video that showcases that.

I'm still trying to sort out how this differs from permaculture, but I think I'll eventually get it sorted out .

 

[Mike Thayer]

I just read a report out of Utah that showed a decrease in yield in corn and wheat after applying biochar. This report said that not only was the yields depressed for several years after application, but the quality of the corn silage from the crop was depressed as well. In at least several of the trials the normal amount of commercial fertilizer was applied. The biochar was applied at a fairly heavy rate. It did not say if the biochar was "charged" with biological microbes or not.

Other articles I have seen said it is important to charge the biochar or else the biochar will " soak" up the nutrients and moisture until a healthy or abundant population of the microbes are established. Dr. Christine Jones says that applying commercial nitrogen will inhibit the production of nitrogen fixing bacteria. So, I am theorizing that unless the microbe population is established in the biochar prior to applying to the soil, there is a deficiency of nutrients available to the crops. Similar to when first converting from conventional tillage to no till farming practices. Producers were able to overcome the yield drag when first converting to no till, by increasing the fertilizer application rate. But this seems like defeating the establishment of a self-sustaining life cycle of microorganisms and a decrease in the use and reliance of commercial fertilizer and other inputs.

Any thoughts or other inputs on my theory?

 

[JustinM]

You bring up some great points Mike. I love your deep thinking on this subject! Your theory of establishing a microbe population in the biochar prior to applying to the soil so that there isn't a nutrient deficiency makes complete sense to me. But I know I'm no biochar authority as I've never worked with it. I've only read about it. To my best understanding, biochar acts like a nutrient sponge, adsorbing nutrients until all surfaces outside and inside the biochar get filled. Now with growers going from conventional till to no-till, the best way to do that is by not applying more fertilizer. Rather it's by applying lower amounts, but more frequently so the crop is being spoon-fed. This is because tillage releases a whole bunch of nutrients very quickly (rapid mineralization). When the crop is being spoon-fed when going to no-till in conjunction with strategic cover cropping, then many growers have reduced their chemical fertility significantly.

 

[Mike Thayer]

An update on my use of biochar: I have fed an1/8th cup of biochar per head a day for the sheep mixed in the grain ration. To my surprise there was no hesitation by the sheep to eat the grain @ 1/2 pound per head with bio char. And this spring during lambing season, I spread a thin layer of biochar before putting out corn stalks for bedding. And then again, each time I added additional corn stalks. I also put a thin layer in the lambing jugs under a layer of wood shavings. I cleaned the jugs after each ewe. My impression was the biochar helped keep the bedding dryer, and to some extend helped with the ammonia build up. I was hoping by feeding the biochar, it would either absorb or limit the methane production during rumination. It did seem like the sheep's breath wasn't as strong. Of course, I don't have any real data to prove any of this.

The biochar was pretty expensive so I don't know if I will do it again.
I will put the used bedding in the compost pile, and then apply the solids to the soil. I am hoping the minimal amount if biochar in the compost will not keep the "goodies" from leaching out into the compost tea if I use the compost for that.