forces in agriculture. These include herbicides for
killing plants, insecticides for killing insects, fungi-
cides for killing fungus and bactericides for killing
bacteria. While these chemicals supposedly only
target specific species, repeated use inevitably kills
some microbial life, both good and bad microbes.
Research has been able to identify some indirect
effects of continued usage of pesticides such as
glyphosate. Microbes that survive exposure can be
genetically altered in a way that is no longer ben-
eficial to the soil ecosystem and they also become
resistant to the chemical intended to kill them.
The destruction or alteration of first-level mi-
crobes can affect the entire soil ecosystem all the
way up to the largest mammalian predators. A
study by Zobiole, et al, from 2011 concluded,
“Glyphosate applied to GR soybean, regardless of
cultivar, negatively impacts the complex interac-
tions of microbial groups, biochemical activity and
root growth that can have subsequent detrimental
effects on plant growth and productivity.”1 While
my company was conducting compatibility research
of our mixture of microbes with various agricultural
inputs at UC Davis we discovered that in-lab tests
confirmed 100% lactobacillus species and yeast spe-
cies in our EM-1 product were killed within 60 sec-
onds of contact with RoundUp.2 There were similar
results with other synthetic pesticides that demon-
36
strated how potent these chemicals are to microbial
life.
What Happens When Soil Microbes Go Out
Of Balance
Microbial communities work in concert (or syn-
ergy) to out-compete antagonistic (bad) communi-
ties of microbes. There is a balance between "good"
and "bad" microbes. Many microbial species (the
good ones) kill or inhibit bad/pathogenic bacteria,
fungi and nematodes (the bad ones) that attack the
root systems of plants. Root health is important for
the exchange of valuable nutrients in the soil. Good
microorganisms improve the soil structure by pro-
ducing glues (polysaccharides), hyphae strands and
tunnels for air and water. Good microbes also eat a
lot of toxic material that would otherwise make for
poisonous soil. An imbalance of soil microbes can
result in parasitic infestations, root disease, break-
down of the soil structure and build-up of toxic
compounds. When soils are repeatedly treated with
toxic chemicals, the balance between good and bad
is disrupted and the soils can actually become toxic
to plants.
Ways to Keep Soil Healthy
Microbe numbers in the soil can be maintained
by making sure the soil has plenty of digestible
plant material (organic matter) with high levels of
www.GardenandGreenhouse.net
June 2018