ISSUE 6 June 19, 2008
MISS ROUNDUP®, MICRONUTRIENTS, AND THEIR UNHAPPY MARRIAGE
Once upon a time, there were micronutrients.
They were needed to increase the happiness and prosperity of farmers in certain parts of the world.
But in North Dakota, sometimes the micronutrients were needed
and sometimes they were not .
Farmers were sometimes confused about what they needed and what they didn’t need.
Friendly people would give steak dinners and encourage farmers to invite micronutrients onto their farms for only a little gold per acre.
The friendly people would provide "testimonials" from other farmers who believed they had received a benefit from micronutrients. Sometimes these people came from the kingdom, but other times these people came from far away, where farm conditions and crops were different.
Farmers would try the micronutrients, and sometimes the fields would be better off- but often they were not.
The unhappy farmers would try to find the friendly people and introduce them to their lawyer, but the formerly friendly people were often hard to find and the farmers remembered that they had forgotten to leave "check strips" on their 1,500 acres of test fields.
The friendly people had often moved to exotic places like Palm Springs after the steak dinner, and besides, even if they were found, the king had outlawed public burnings of traveling friendly people years ago.
And many farmers were sad because they hadn’t read the "Terms and Conditions of Sale".
The farmers decided to go to an Extension meeting, where a soil fertility wizard would help them foretell what micronutrients might be important for which crops.
This is what they heard-
"Micronutrient needs in North Dakota are crop specific."
"Antagonism or non-performance is possible if metals are applied with glyphosate."
So the farmers came away from the Extension meeting knowing that only four crops in the region benefit from zinc application, only a few crops from iron (and then more from seed-placed EDDHA than a foliar spray), and there was no need at all for copper, manganese or boron in the kingdom for corn, soybeans, canola or sunflower.
But still the friendly people tell them through the magic screen and through the air waves that micronutrient mixes are important and why not mix it with their herbicides.
And it came to pass that a young maiden- Miss Roundup®, came to the kingdom. The farmers were delighted to see her, because everywhere she went, evil weeds would die and fields made pure and clean.
Farmers courted Miss Roundup® and eagerly sent gifts of Tech Fees to her guardians as thanks for her many blessings.
Miss Roundup® performed her magic with a group of approved attendants, called Adjuvants. However, friendly people, seeing an opportunity, suggested to farmers that perhaps micronutrients could accompany her when she performed her magic in the fields, and therefore accomplish a weed and feed blessing.
Farmers were excited, because they could use the friendly people’s micronutrients without an extra trip into their fields. Miss Roundup® could accomplish the task with no increase in gratuity to her guardians.
However, one wise old farmer, a true Consultant in the kingdom, suggested that they go to the Extension wizard and ask him for wisdom. And it came to pass that they visited the wizard, and unable to bestow wisdom, offered to share data instead.
This is what he shared-
"In trials near Walcott, ND in 2002, application of an iron chelate increased the phytotoxicity of three postemergence broadleaf herbicides on soybeans and reduced soybean yield an average of 4 bu/acre.
In Michigan research, in micronutrient and Roundup® tankmixes, velvetleaf control was reduced 50% with iron and zinc chelate additions and lambsquarter control was reduced 50% with iron. Adding more ammonium sulfate, or increasing Roundup® rate increased control, but reduction in efficacy was still recorded. Manganese as ligno- and sulfate fertilizers decreased glyphosate absorption by weeds, manganese-EAA chelate reduced efficacy, but the mechanism was not known, while manganese-EDTA had no effect (manganese deficiency is common in Michigan due to their inherently low soil manganese availability, but not in North Dakota)."
In Virginia, manganese tank mixes reduced control of lambsquarter, smooth pigweed and large crabgrass.
A number of studies have shown that micronutrient additions to glyphosate can reduce weed control. Even applications of micronutrients a few days before glyphosate application can reduce weed control. Reductions in weed control may not always happen, and additions of extra ammonium sulfate may help to reduce the reductions, but farmers want clean fields, so the risk of unhappiness is there."
So the farmers left the wizard and considered the wisdom of marriage between Miss Roundup® and micronutrients.
Some were still enchanted by the lure of magical riches promised by friendly people through visitations by micronutrients on their farm that could be carried by Miss Roundup®.
Some weeds were not vanished by the marriage of Miss Roundup® and micronutrients, and the farmers lost their farms and became insurance salesmen.
Others took the Extension wizards words to heart and refused to marry Miss Roundup® with micronutrients, and lived Happily Ever After.
Roundup® is a product licensed and registered by Monsanto Corporation and neither Dr. Franzen nor North Dakota State University make any promotion of its use over similar products.
Dr. Dave Franzen
NDSU Extension Soil Specialist