USDA Scientist's Research Finds Roundup Damaging Soils (and Plants)

Prof. Robert Kremer,
University of Missouri

New USDA research is showing that Roundup is harmful to soils and plants.

Midwestern corn and soybean farmers are damaging their soils by using large amounts of Roundup, says USDA researcher microbiologist Dr. Robert Kremer of the University of Missouri.

You can read more about his remarks in the Reuters coverage of the event here. 

The article begins: "The heavy use of Monsanto's Roundup herbicide appears to be causing harmful changes in soil and potentially hindering yields of the genetically modified crops that farmers are cultivating, a government scientist said...Repeated use of the chemical glyphosate, the key ingredient in Roundup herbicide, impacts the root structure of plants, and 15 years of research indicates that the chemical could be causing fungal root disease..."

Kremer's research has found that Monsanto's Roundup-ready GMO plants exhibit the following:

"This [Roundup-Ready] system is altering the whole soil biology. We are seeing differences in bacteria in plant roots and changes in nutrient availability. Glyphosate is very systemic in the plant and is being released through the roots into the soil. Many studies show that glyphosate can have toxic effects on microorganisms and can stimulate them to germinate spores and colonize root systems. Other researchers are showing that glyphosate can immobilize manganese, an essential plant micronutrient."

Granted, wine grape growers in California aren't using Roundup-Read (GMO) seeds. But they are using a heap-o Roundup, according to the California Dept. of Pesticide Regulation - about a pound per acre on 450,000 acres, across the state.

Kremer's research was unveiled in the European Journal of Agronomy in 2009 (link to issue home page here) and he spoke about this year at the August conference of the Organization for Competitive Markets (OCM), a farm-based nonprofit, in Kansas City, Missouri.

Here is what the journal's introduction to the special issue says: (Note: glysophate is Roundup)

"Although glyphosate is the most widely used herbicide worldwide (Woodburn, 2000), several problems associated with glysophate interactions with plant nutrient availability, transfer to and effects on susceptible crops, indirect effects on rhizo-sphere microorganisms and plant pathogens, and development of glyphosate-resistant weeds have raised serious concerns regarding the sustainability of cropping systems in which glyphosate is the primary weed management strategy."

Read the full text of his research in the European Journal of Agronomy here.

For years Monsanto has been telling farmers, growers and the public that Roundup quickly dissolves leaving no trace behind. Untrue, says the scientific literature.

As Kremer's article states:

"In contrast to generalizations that glyphosate is tightly bound and inactivated in soil, numerous studies show that glyphosate is available to soil and rhizosphere microbial communities as a substrate for direct metabolism leading to increased microbial biomass and activity (Haney et al., 2000; Wardle and Parkinson, 1990). Indeed, Simonsen et al. (2008) recently demonstrated that agricultural soils amended with phosphorus fertilizers are high in unbound glyphosate because soil sorption sites are occupied by competing phosphate ions; thus, glyphosate remaining in the soil solution is vulnerable to potential uptake by plant roots, microbial metabolism, or leaching into groundwater [bolding mine]."

(This seems to be illustrating the basic concept, once again, that nothing in nature is ever separate.)

Here is coverage from OCM's own Sept. newsletter (see page 11) about Kremer's remarks at the 2011 conference:

"Dr Bob Kremer of Missouri University discussed his research that indicates a possible change in soil health due to accumulated glyphosate residues in both soils and plants...all the indications are that increased levels of glyphosate result in plant nutrients being tied up in the soil and unavailable while fungal diseases thrive for the same reason.

Dr. Kremer said, “We need to develop an agro-ecological approach” to better manage the impacts of relying so heavily on one or two types of crop pest control. Dr Kremer added that potential soybean yields could be much higher than the current mid forty-bushel nation- al average, perhaps up to 100 bushels regardless of genetic modification, if good soil management is applied."

Prof. Kremer says the solution to the over use of Roundup is - surprise, surprise - organic farming. "More farmers are interested in using cover cropping to maintain soil quality and other organic amendments. But it’s a steep learning curve for them,"he said.

[That makes publication of the new U.C. published Organic Winegrowing Manual all the more praiseworthy.]

Now... how/can we get an organic viticulture class and an endowed chair at U.C. Davis to speed things up?