Focus: From ashes to fly larvae, new ideas aim to revive farm soil

Desert Control AS

30/01/2023 12:01

By Rod Nickel
       WINNIPEG, Manitoba, Jan 30 (Reuters) - As extreme
weather and human activity degrade the world's arable land,
scientists and developers are looking at new and largely
unproven methods to save soil for agriculture.
    One company is injecting liquid clay into California desert
to trap moisture and help fruit to grow, while another in
Malaysia boosts soil with droppings from fly larvae. In a Nova
Scotia greenhouse, Canadian scientist Vicky Levesque is adding
biochar - the burnt residue of plants and wood waste - to soil
to help apples grow better.
    Long-established soil preservation techniques, such as
tilling less and sowing crops during off-seasons, are proving no
match for more frequent droughts, floods and temperature
extremes. Soil erosion is depleting dirt's ability to produce
food, and could lead to a 10% loss in global crop production by
2050, according to the UN's Food and Agriculture Organization.
        New "soil amendment" solutions, which improve the
physical properties of soil, may complement the traditional ways
-- if they prove profitable and effective. 
    Biochar, liquid clay and fly larvae droppings are all in
limited commercial production. Development of such solutions has
accelerated in recent years as soil degradation worsened, said
Ole Kristian Sivertsen, chief executive of liquid clay company
Desert Control  DSRT.OL , which made its first commercial sale
in December.
    Bayer AG  BAYGn.DE , the world's biggest seed company, is
among the companies looking at new ways of regenerating soil
through Leaps by Bayer, its venture capital unit, said Matthias
Berninger, Bayer's head of sustainability.
    Bayer and other companies are already working on
non-chemical ways to add nutrients to crops such as adding
microbes into soil but products aimed at regenerating farmland
go further. Some, like liquid clay and biochar add nutrients
while also improving the ground's ability to retain water, and
require fewer applications than fertilizer. 
    "We have really started to focus on the soil in ways we
traditionally wouldn't have done," Berninger said in an
interview.
    Dark Earths
    Biochar is an artificial means of creating a carbon-rich
product to boost soils, modelled after exceptionally fertile
patches of Amazon rainforest called "Dark Earths" that were
produced over time as a byproduct of cooking, animal
decomposition and manure.
    Biochar could be a "great opportunity" for trapping
plant-sustaining carbon in the soil, Levesque said, adding that
biochar also acts like a water sponge. 
    Her research, which started in 2012, has shown that clay
soil treated with biochar emitted drastically less nitrous
oxide, benefiting the atmosphere and trapping more carbon in the
ground where it can boost plant growth.
    Some types of biochar increased yields of greenhouse
tomatoes and sweet peppers by 32% and 54% respectively, while
requiring less fertilizer, due to biochar spurring reproduction
of bacteria that benefit plant growth.
    More research is needed, however, before scientists know how
effectively biochar could regenerate different types of soils
around the world, she said.
    Norway-based Desert Control has spent 18 years and $25
million developing liquid clay to boost soil. Last year, it
injected its product into a patch of U.S. desert, where the clay
binds with sand to better retain water and nutrients.
    Preliminary data from a five-year trial showed that in sand
treated with clay, romaine lettuce hearts were on average 21-53%
larger than romaine grown under the same conditions without
clay, said Robert Masson, an official at University of Arizona's
Yuma County Cooperative Extension, who grew the plants.
    In November, Desert Control signed a $182,000 contract with
Limoneira Company  LMNR.O , which will initially apply liquid
clay to 4,000 trees on two of its citrus farms in the
drought-stricken states of California and Arizona. Depending on
results, Limoneira intends to expand application in the fourth
quarter.
    Each application lasts up to five years.
    "Cover crops and no-till are good practices but they are far
from enough," Sivertsen said.
    In Malaysia, Nutrition Technologies produces "soil
conditioner" from frass - the waste and skin of Black Soldier
Fly larvae. Composted frass led to a 12% increase in
plant-nourishing soil organic matter, something that otherwise
declines over time, according to the company's research. 
    Nutrition Technologies, which started in 2015, sells an
average of 200 tonnes of frass monthly in Malaysia, mainly to
farmers who apply it to leafy greens, cucumbers and fruit, said
Martin Zorrilla, the company's chief technology officer.
        The company raised $20 million in September, its most
recent funding round.
    While most Malaysian fertilizer producers now sell frass,
volumes are still too low to draw the attention of global
agriculture companies, Zorrilla said.
    "Ultimately, soil is a living system, which is one reason it
takes natural processes so long to build soil and why it is so
easy to lose it," he said.
 (Reporting by Rod Nickel in Winnipeg; Editing by Caroline
Stauffer and Chris Sanders)
 ((rod.nickel@tr.com; Twitter: @RodNickel_Rtrs;))