Regenerating South Texas Plains with Poultry-Inoculated Biochar

Project Overview

Project Type: Farmer/Rancher
Funds awarded in 2024: $15,717.00
Projected End Date: 03/31/2026
Grant Recipient: Smith Pastures, LLC
Region: Southern
State: Texas
Principal Investigator:
Sandy Smith
Smith Pastures, LLC


No commodities identified


No practices identified

Proposal summary:

Biochar presents a viable solution for remediating depleted soil
by increasing soil carbon as well as creating protected space for
increased microbiological activity and moisture retention. Its
structure has been described as similar to a coral reef for
providing protected spaces for life to thrive. A single gram of
biochar has approximately 500 square meters of surface area. This
large area provides a home for beneficial microbes and fungi,
enhancing soil fertility. Biochar attracts and holds moisture,
improving the drought tolerance of pasture. Biochar also attracts
fertilizers such as phosphorous and nitrogen for later release,
and helps prevent its degradation into nitrous oxide, a potent
greenhouse gas. Biochar is a permanent soil amendment, with
permanent benefits after the ideal biochar to soil ratio has been
achieved. One objective of the project is to determine whether
distributing biochar, made from recently cleared brush, on
selected paddocks will increase organic matter in the soil.

However, initial biochar application has resulted in a decrease
in some pasture yields over the first year or two. Most biochar
materials are not substitutes for fertilizer, so adding biochar
without necessary amounts of nitrogen and other nutrients cannot
be expected to provide immediate improvements to crop yields.
Instances of decreasing yield due to a high biochar application
rate have been reported because biochar has a porous nature that
tends to attract and retain the existing biology and moisture
that would otherwise be feeding the forage. To mitigate the
initial retention issue, inoculating biochar with liquified,
mature organic compost (e.g., compost tea) has shown
effectiveness. However, it can be burdensome and time-consuming
to harvest, age, and store inoculants, and then distribute
inoculated biochar throughout the soil. Therefore, our second
objective is to determine whether inoculating biochar by having
chickens consume it and distribute it on pasture through their
manure will add appropriate nitrogen and other nutrients to speed
up the increase in organic matter.

This project proposes to take mechanically removed brush stands,
render them to biochar, and then introduce the biochar to an
experimental group of pasture raised poultry as a feed
supplement. Pasture raised poultry practices include housing
birds in floor-less pens that are moved around on grasslands.
This provides the birds weather and predation protection while
offering direct access to consume forage and distributing the
resulting nitrogen-rich manure throughout the pasture. We also
anticipate the consumption of biochar will serve to improve the
overall bird health and performance but this is ancillary to the
improvement of the soil.

The biochar will be derived from woody masses removed from our
property to create pasture area suitable for implementation of
pasture raised poultry operations. The woody masses are currently
piled high throughout the property, are dried and ready to use to
create biochar.

There are several methods to producing biochar, each with varying
degrees of efficacy. We intend to employ the Cone Pit method,
that is to dig a large, inverted-cone-shaped pit about 10 feet
deep. The significance of the inverted cone is to control the
combustion process by only allowing oxygen to the top layer where
the flame is; the area below the flame is oxygen starved but
remains hot due to the flame above heating it like an oven.
Large, uncut feed stock (woody masses of tree prunings, brush,
branches, sticks and other biomass waste) serves as the lower
layer and the top layer of wood mass. The use of large feed stock
requires less preparation & labor than other methods.

The process begins by starting a small fire in the Cone Pit then
introducing feedstock to the top. Additional feedstock is
continually added until the pit is filled just over the top. The
fire is monitored closely to ensure an oxygen-free environment
below the top. The elimination of oxygen allows for the critical
pyrolization process that creates biochar. The heat causes
flammable gasses to evolve from the biomass and rise to the top,
where they are burned in the flame zone. The fire is maintained
and the feedstock is ‘cooked-down’. When there is no more active
flame, the process is complete. Then the entire pit is either
quenched with water to stop the process or the top of the pit can
be covered with dirt, preventing oxygen from entering and
allowing it to extinguish itself over time. Once cooled, the
resulting mass is crushed to a desirable granular size. The mass
can be manually extracted and crushed with tools like shovels or
tampers or mechanically with a small wood chipper.

We will follow The International Biochar Initiative’s guidelines
for quantity disbursement methods for application. However, there
is no published material on using it as a feed supplement.
Poultry tend to consume different components of feed at different
rates depending on weather, age and other factors. We will
introduce the granular biochar to their free choice feed and
monitor consumption closely to determine the optimal levels
throughout the trials. The birds will consume the mixture and
distribute it on pasture through manure, thereby depositing
inoculated and moist carbon directly on the soil.

Project objectives from proposal:

Our project is an on-farm demonstration to test how efficiently
and quickly depleted soil can be regenerated and brought
into agricultural production through the use of biochar or
inoculated biochar as an amendment.

We will change an important aspect of our current farm operating
system to determine the efficacy: introducing inoculated biochar
to soil by adding it to current pastured poultry rations. The
variable involves both biochar and inoculated biochar. We will
make the biochar on-farm using native woody brush material
previously removed to re-create native perennial grass pastures.
For inoculated biochar, the biochar will be consumed by the
animals and deposited to the soil in the animals’ manure.

For this project, we will transfer our current pasture raised
meat bird operation to newly-cleared land previously inundated
with brush. In total, we will divide our flock into two groups
and dedicate up to nine recently-cleared acres for this project:

  1. one control plot for rotationally grazed
    poultry (our current practice);
  2. one experimental plot amended with only
    biochar and no livestock;
  3. one experimental plot of rotationally grazed
    poultry fed free choice biochar that will be distributed as
    inoculated biochar in their manure.

We will use between one to three acres for each plot, as
necessary, to ensure chicken tractors do not travel over the same
pasture area for one year. We will conduct soil testing before
the project commences and every six months thereafter. Using best
practices, we will take 20 to 30 subsamples from the experimental
plots to find a true average. This will account for the wide
variability that can occur in soil and forage conditions.

In addition to soil testing, we will make weekly observations,
take photos and videos. and capture detailed notes about poultry
biochar consumption and what is happening on each plot. We will
also monitor the growth of grasses and forbs using the Savory
Institute methods (for which Steve has been trained), and track
environmental factors such as rainfall and temperature. Ancillary
to the project, we will also monitory poultry performance.

Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.