There is a growing concern in the use of glyphosate on farms.
Here is a quote from http://www.soilcursebuster.com/ :
"Let’s begin with the claim which French scientists and regulators have officially disputed. Glyphosate is bio-degradable. Many producers have made comments that there seems to be some residual activity with the chemical. Here is a quote from Huber and Johal from the European Journal of Agronomy 31 (2009) 144–152. ( Dr. Don is a good man and respected scientist, another farm boy who really studied his lesson.)
Detoxifying glyphosate in root exudates may occur in highly calcareous soils or soils with high levels of soluble metal nutrients through chelation to reduce its impact on soil organisms. Toxicity of glyphosate to Mn-reducing and synergistic nitrogen-fixing organisms in the rhizosphere can have serious consequences for sustainability of legume production.
The toxicity of the chemical you see is not limited to the chemical contained in the spray tank solution which unavoidably comes into contact with the soil. The toxicity Huber refers to here is in the root exudates or jelly-like substances that are excreted from the root of the plant which is sprayed with glyphosate. It has mistakenly been thought this reaction takes place only with GT (glyphosate tolerant) plant tissue. Huber again
. . . root rot is more severe when glyphosate is applied to soybeans under weedy conditions even though the weeds may not be hosts for Corynespora cassiicola. The weeds serve to translocate and release more glyphosate into the rhizosphere environment to reduce the population of Mn-reducing organisms and increase Mn oxidizing organisms. This change in soil biology limits manganese availability for plant uptake and active defense reactions, and acts synergistically with Corynespora to increase disease ( Huber et al., 2005 ).
So, even the weeds or other non-gmo plants which are sprayed with glyphosate give rise to soil contamination of the chemical. That contamination changes the ability of the soil to make certain key micro-nutrients available to the plants and soil microbes."
I know Jim personally and he is avid about the use of glyphosate on soil and willing to testify in Congress on its pitfalls. I have other highly regarded friends who won't recommend or use glyphosate on their farm.
I quit using glyphosate when it wouldn't kill the weeds around here anymore. Also I got tired of the Manganese difficiency it causes in legumes. That yellow flash may just be the tip of the iceberg.
People like me were used to sell the attributes of RoundUp, the first brand of glyphosate many years ago. Even though it is broadspectrum as a weed killer, the LD50 and half life is low. "Safer than a cup of coffee or aspirin" they would say.
Maybe that part of a half life remaining really messes up soil biology?
Genetically modified corn, that's a whole 'nother issue, digestion, liver problems etc in dairy cows to humans. I do know New Zealand didn't allow it in their country and the Japanese paid a nice dividend on my non GMO soybeans for tofu.
It is all controversial and not mainstream. Most of the food coming out of our country is genetically modified and most of the soil is treated with glyphosate to control weeds.
Maybe it's an attempt to bring down Monsanto. I don't think so, I think it is just science evolving as it always does.