Future Burns Bright for Biochar

Photo of biochar

This is a big handful of biochar.


Chances are that you haven’t heard of biochar, but I’m predicting right here that it has a bright future.

Proponents of biochar–a versatile form of charcoal that’s being used for everything from increasing crop yields and conserving water to removing toxins and sequestering charcoal—gathered in Amherst, Mass. Oct. 13-16 to share knowledge and strategies for advancing its use.

The use of charcoal for agricultural purposes in China, Japan and Amazon is centuries old, but the word “biochar” is less than ten years old and still relatively unknown. Biochar is produced when “biomass”—plant and animal-based materials, such as woodchips, cornstalks, manures, and lumber leftovers—is heated without oxygen (pyrolysis).

biochar logoI attended the first two days of the 2013 USBI North American Biochar Symposium, titled “Harvesting Hope: The Science and Synergies of Biochar,” and met a retired Dupont employee, a Nevada forest manager, a New Hampshire man planning to launch a business selling biochar, a Mexican entrepreneur seeking to create furniture and art containing biochar, and assorted farmers, researchers, and climate change activists. Everyone had a story to tell about the benefits of biochar.

For example, I had breakfast with Dusty Moller, a Wood Utilization Manager in Las Vegas, who’s been using biochar as a soil amendment in a piñonjuniper forest in Nevada.  “We’re adding 1-2% biochar (by weight) to the soil, along with manure,” Moller said.  “The biochar makes the plants grow better.”  He added, “It also helps the soil retain moisture longer, so you can use less water.”

As far as I’m concerned, anything that can reduce water usage in Nevada is worth all the slot machines in Vegas.

Up till now, Moller has primarily purchased his biochar, but he’s brought in two small units that can be used to produce his own biochar on site.  The trees and brush that need to be cleared for good forest management will be used to create the biochar for amending the soil.

This smart use of resources is typical of the current biochar movement, which, up till now, has tended to be small-scale and decentralized. Some worry that a scaled-up biochar industry might encourage entrepreneurs to clear-cut virgin forests or use arable land to grow biochar feedstock instead of food.  Some bad examples of this behavior have already emerged in the biofuels industry.

Based on what I observed, however, I think this is unlikely.  For example, one of the conference attendees described how he gets paid to remove invasive species and then uses that material to produce biochar. Even one of the largest companies in biochar, Cool Planet Energy Systems, which has attracted investors like BP, Google Ventures, and ConocoPhillips, aims to be sustainable. Cool Planet’s primary business is creating biofuel from non-food biomass, but since biochar is a byproduct of their biofuel production, they’re also developing a biochar soil amendment under the name Cool Terra.  According to Cool Planet, field trials of their product have shown yield improvements of 60% and input reductions of 40%.

Biochar products

A display of different types of biochar.

In order for the biochar industry to truly take off, however, I think it needs to develop clearer and simpler protocols for how to use it. The characteristics of each type of biochar, such as its water retention capacity, ability to sequester heavy metal, and its pH level, vary somewhat, depending on the materials, temperature, equipment and process used to make it. In addition to the biochar itself, other variables can also alter its impact, such as how much biochar is applied and whether the char is used on its own or in conjunction with other materials, such as manure. Soil conditions also vary; the more deplenished the soil, the more it’s likely to benefit from biochar.

Biochar has so many other uses beyond soil productivity, and these also need to be better documented. For example, biochar is increasingly being incorporated into animal feeds to serve as a binding agent, improve feed conversion ratios, and reduce methane emissions and odor. Vineyard owners are using their waste product to produce biochar so they can neutralize toxins and increase the water holding capacity of their soil.  And biochar is playing a role in habitat restoration and remediation.

Despite the lack of clear and simple protocols, I can’t wait to try using some biochar in my garden.  There are lots of tips and suggestions on the Internet, so I’ll look at a few of them and give it a whirl.  My garden’s pretty small, but I’m planning to divide up one of my raised beds and only put biochar in half of it, so I can compare the results.

The future’s so bright, I may have to wear shades.

Biochar photo: Creative Commons by visionshare

This entry was posted in Farms, Gardening and tagged , , , . Bookmark the permalink.

2 Responses to Future Burns Bright for Biochar

  1. Dusty Moller says:

    Well written, Myrna…here’s some instruction that can guide you in your effort:

    For use in nursery applications with “supercells”:

    The following 3 replications are recommended for initial planting demonstrations:

    1.        Control:  Their typical mix of 5 gallons peat moss + 2.5 gallons perlite + 2.5 gallons vermiculite + 1 cup of Osmocote.

    2.       75:25 split:   Use this ratio to substitute biochar for peat moss.  Using 75% peat moss and 25% biochar.  Or, 3.75 gallons of peat moss and 1.25 gallons of biochar.   Keep all of the other components constant.

    3.       50:50 split:  Same as #2, but 50% peat moss and 50% biochar.  All other components remain constant.

    Other ratios may be substituted but should never approach 50% biochar—50% other ingredients.

    For raised bed, vegetable or flower planting from seed or transplanting:

    A recommended 1% application rate in a square foot of garden soil, at a tillage depth of 6 inches or so, requires about 1/2 pound of char. Depending on the density of the char, that would convert to about 3 cups/per square foot. Char should be ground to a fine, sawdust-like fraction. Larger pieces and chunks will gradually work their way to the surface, defeating the purpose of the char. (A rolling pin used for baking makes a nice pulverizer.)
    When applying the char, adding some inorganic nitrogen fertilizer can offset the initial absorptive activity of the char. As stated, once the mycorrhizal community is established, overall fertilizer needs may diminish.

    (These instructions were compiled by and additional information concerning their application can be obtained from Wood Utilization Program Manager Dusty Moller at dmoller@unr.edu ; 702-866-5962. The program’s website address is: http://unrbep.org/resource-conservation/woody-biomass-utilization/ )

Leave a Reply