Let’s talk about herbicides. It’s almost the time of year when we’ll start seeing the spraying equipment hitting the fields around here, so let’s talk about herbicides, one in particular called dicamba. And if you read the agriculture press, you’ll be seeing articles like this one that warn of the pitfalls of using this old-but-new-again herbicide: Caution Lights Ahead For Dicamba Use | Ag Professional. (And before you ask, yes, there are already dicamba resistant weeds out there and one experiment showed it took one type of weed only three generations to develop resistance to the herbicide. <read that article here>)
Now I should point out that dicamba has been around for a long time. It was developed back in the late 1950s and has been on the market ever since. It’s used to control broadleaf weeds and brush. What’s new about it is that Monsanto has developed a line of dicamba resistant crops such as soybeans which can tolerate the herbicide. With these crops being resistant to both glyphosate, the active ingredient in RoundUP, and dicamba, the hope is that this double dose of herbicide will help to control weeds that are resistant to glyphosate alone.
But there are, as always, problems.
The first of these is dicamba itself. It volatilizes easily, going into vapor, which then moves over large areas. It also is subject to drift while spraying. The droplets from the sprayers can drift over large areas as well. This combination of easy volatility and tendency to drift makes it troublesome to work with because it can spread over large areas, killing or damaging plants well outside of the area being treated. In order for dicamba to be used in the way Monsanto wanted, special blends and compounds had to be created to help prevent the easy volatility and drift of the product so it wouldn’t contaminate adjacent fields.
Monsanto decided to sell its Xtend seeds before the herbicide blend it was designed to work with was approved by the government. The result was that farmers who should have known better planted the seed, and then used dicamba blends that were not approved for use, and tens of thousands of acres (some estimates are in the hundreds of thousands of acres) of crops were damaged or killed by the drift from the herbicide. There are currently lawsuits going on against Monsanto claiming the company is responsible because it released the Xtend seed before the accompanying herbicide blend was available, and Monsanto should have known that some farmers would use dicamba illegally.
The new legal blend is now available, but even that isn’t going to solve the problem. There are a whole host of restrictions, requirements and warnings adorning the labels of the new herbicide. It can only be used with a particular type of sprayer nozzle, has to be applied no more than X inches above the weeds, has to be used at a certain point in the weeds’ life span, the wind can be no more than 10-15 MPH… The list goes on and on. All of the warnings and requirements indicate that this new “safer” blend isn’t all that much safer than the original form of dicamba was.
And in the long run dicamba is going to end up being just as useless in controlling weeds as glyphosate is becoming because as that article I linked to at the beginning points out, weeds will quickly become immune to it as well.
I keep wondering how much longer we can keep this up, concocting ever more toxic and complex blends of herbicides to try to control weeds, when we know that it is, at best, a temporary fix and that the weeds will eventually become immune to even that.
Meanwhile over in France the government has been trying to push things in the other direction, trying to get agriculture away from the ever increasing reliance on herbicides and pesticides. France <story here> has set a goal of cutting the use of pesticides of various types by 50% over the next ten years through the use of alternative methods of pest and weed control. How successful the program has been is a bit questionable, but studies have indicated that farms could significantly cut their use of pesticides and herbicides without a loss of income. But it would require some significant changes in farming practices.
Can we get away from this apparently never ending cycle of herbicide/pesticide resistance? We’re going to find out and in the not too distant future because the current situation simply cannot continue indefinitely.