The “Dicamba damage” story has gotten such broad attention that it’s being picked up by the Wall Street Journal in a feature today. This link takes you to their report, although you’ll need a WSJ subscription to read the full story.
July 11, 2017 — So far, most official damage complaints to regulators have shown up in Southern states: Arkansas (596), Missouri (123), Tennessee (76) and Mississippi (60).
Missouri ag officials say they hope their restriction will be short-lived, pending new label restrictions specifically for Missouri. AgWeb has an update on this.
Successful Farming’s website, agriculture.com, has a July 11 report, “Why dicamba technology is in trouble.”
July 14 update: Iowa weed specialist Bob Hartzier says Iowa farmers are joining the club of growers reporting dicamba drift damage.
Crop consultant Bob Streit reported on this subject: “The news about Dicamba soybeans and drift complaints from the application of the herbicide keep coming out of MO, ARK and now Tennessee. Aaron Hager with the University of Illinois is reporting their first complaints. This is before the major lawsuits over 2016 drift have been heard in court. If you noticed the lack of boxes of Missouri peaches in Iowa grocery stores last summer it is because they had a major Dicamba drift even near their groves last year, as did Stark Bros. This has lead to class action suits in Missouri that keeps adding plaintiffs to the suit. You can refer to Bader Farms and look up the details. One side claims they were not liable because it was not their product drifting. The second side lays an analogy related to being responsible for an attractive nuisance, as in leaving a ladder up against a barn that some kids climb before falling off. Taming a product with a high vapor pressure may not be possible. If the German chemists have difficulty doing so, can anyone?”
Some of our Iowa farmer clients who use WakeUP Summer in herbicide mixes tell us they’ve applied dicamba this spring, but none have told us of complaints from neighbors or evidence of damage from drift on their own farms. They’re being very cautious about avoiding windy conditions and temperature inversions.
We’ve always recommended medium to coarse spray tips and lower pressures to reduce drift and evaporation. That’s our general prescription with foliar nutrients — or herbicides and fungicides. With WakeUP Summer in the spray mix, a droplet of any size sheets out across the leaf because of very low surface tension in the spray solution. You don’t need a mist if you have WakeUP. Before colloidal micelle technology came along, “fog” sprayers or those which injected air with venturi systems were often recommended.
Some of our growers are going to hooded sprayers for further dicamba safety. We’ve not seen any detailed data on how a hooded sprayer reduces drift, but it should help. If you have 30-inch soybeans rows instead of drilled soybeans, splitting part of the spray with drop nozzles between the rows would release half of the spray delivery below the top line of the canopy, out of the wind. When we spray soybeans before 50% canopy closure, we sometimes use an drop extension with two swivel nozzles with fan tips, which spray horizontally into the row on each side.
Dicamba’s synthetic auxin mode of action is roughly like 2,4-D on steroids — it stimulates growth beyond the plant’s ability to metabolize nutrients for that growth, and the plant dies. With dicamba, the impact is so intense that even vaporized chemical can cause curling and reduced performance of sensitive crops. Leaf “cupping” and curling are typical, as in the photo below, from the saveourcrops.org website.
The “big picture” of weed resistance and spray drift problems for contact herbicides is intensifying needs for early-season, pre-merge weed control herbicides. We’re seeing many cornfields in our neighborhood of northeast Iowa where only premerge weed control was used, and they look clean. An alternative would be premerge herbicides followed by light cultivation in the top couple of inches — which could be tolerated by at least some no-till farmers. Only the top couple of inches are disturbed, and most nightcrawlers and earthworms live deeper. Another benefit is that creating a crumbly layer of soil at the surface reduces capillary action and evaporation loss. Also, firms like AgriEnergy Resources have documented that a light cultivation of corn, including moving some soil over roots, increases yields about 5 bu. per acre. We’d reason that part of the yield increase is a burst of carbon dioxide release from biological activity in the soil, plus an increase in gas exchange as more oxygen enters the newly permeable soil surface. Almost half the biomass in a bean crop comes from CO2 released from the soil, under the crop canopy.
A secondary benefit of going premerge-only on herbicides is the opportunity to reduce seed costs. Unless you need Bt or other insecticide traits, you wouldn’t need to pay for seed with GMO traits designed to resist glyphosate, dicamba, or glufosonate.
Already, we’re seeing greater interest in non-GMO corn and soybeans each season.
So this experience with a dramatically effective new herbicide could lead to a fresh perspective: Long-term, how much can farmers rely on toxic technologies to deal with weed and pest pressure? Are there other, more renewable and health-friendly modes of farmer action?
Embedded within that question is another issue: Have corporate pressures on the regulatory agencies and media constrained the more “difficult” facts about GMO technology and linked toxic chemicals? We’re aware of the wide points of view on this — but here’s an intriguing inside report from Paul D. Thacker headlined: “Flacking for GMOs: How the Biotech Industry Cultivates Positive Media — and Discourages Criticism.” The publication carrying Thacker’s story, The Progressive, is itself not exactly a scientific journal. But we welcome an array of points of view.
One just-posted point of view on media manipulation and disinformation comes from Jeffrey Smith, Institute for Responsible Technology, writing about internet trolls paid by the multinational chemical firms.