Page 47 - Grapevine July-Aug 2020

Around The Vineyard

Is Soil Restoration Possible? Principles of Conservation Agriculture

“The problem with long-term soil degradation is To assess if these theories could be implemented
not that we farm. The problem is the way we’ve on a large scale, Dr. Montgomery
been farming. Tillage has been a major destructive visited farms in Equatorial Africa, Central America
element in human histo-ry,” said Dr. Montgomery. and all across North America. What he found was a
common recipe for rebuilding soils.
While traditional farming methods account for the
loss of a millimeter to a millimeter and a half of soil First, he said, ditch the plow. Minimal tilling can
each year, no-till farming only erodes less than a produce better results, but more car-bon generates
tenth of a millimeter of soil during the same period. when not using a tiller. Second, cover up the soil by
maintaining perma-nent ground cover using cover
When Anne Biklé, Dr. Montgomery’s biologist crops and retaining crop residues. Finally, grow
wife, turned their degraded yard into a garden, diversi-ty. Rotating three to four crops will break up
she added organic matter consisting of compost pathogen carryover. In a vineyard, one can achieve
and mulch. After a decade, their yard went from this by rotating what’s growing between the vines.
1% organic matter to 12% in some places. In their
book, “The Hidden Half of Nature,” they attributed According to Dr. Montgomery, these principles
this shift to the work done by trillions of micro-or- could be scaled up or down, depending on the
ganisms that were feeding underground. This zone, farm, within two decades. Restoring agricultural
called the rhizosphere, is one of the most life dense soils in this manner can help increase farm profit-
areas on the planet. Dr. Montgomery described the ability, feed the world, help with climate change
rhizosphere as “a biological bazaar where microbes and prevent envi-ronmental degradation through
and plants trade nutrients, metabolites and exu- non-chemical practices.
dates.” Like any living organism that consumes
something, the plants metabolize the organic mat- How Microbes Relate to the Wine World
ter and produce waste products like growth hor-
mones. Discussions about terroir focus on climate and
soil; however, Dr. Montgomery sug-gests rethinking
Understanding the symbiotic relationships terroir in terms of the microbes, which are related
between soil microbiota and plants presents farm- to climate, soil and geology. “As we examine the
ers with two very different diets for feeding their relationship between the soil, the vines and the
plants. The first is the fertilizer diet, where if you wines people enjoy, we should think about how the
give a plant enough fertilizer, even bad soil can microbial ecology is a big part of that foundation.”
produce big yields. How-ever, as Dr. Montgomery
assessed, once the plants get all the significant ele- Recent journal articles have begun to cover the
ments they need for growth, they stop investing in landscape of microclimates, including those of
their root system. “This means they’re not get-ting a particular vineyard. Microclimates affect the
as many micronutrients, like zinc and copper, that microbes that live in the rhizo-sphere around the
they need for health, which those microbial part- roots of grapevines and can carry through to the
ners provide.” winemaking pro-cess.

In comparison, growing plants in healthy, fertile “Microbial abundance and diversity come into
soils that have more organic matter to feed those play on leaves, roots and fruit, and then carries
microbes will produce comparable growth. In addi- on into the fermentation process. How you oper-
tion, farmers get the ben-efits of mineral micro- ate your vineyard will determine what you will
nutrients and microbial metabolites. Simply put, have in terms of the fungal community,” said Dr.
organic matter produces higher carbon in the soil. Montgomery. “Hence, understanding the role of
microbial ecology is important for rebuilding soil

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