Wednesday 23 March 2011

One More Round of Herbicide Spraying

It's always nice when you can clearly dump things into the good or bad box, and be done with it. I've always found the chemistry, politics, and economics of herbicides makes that difficult. They're by far  the most widely used pesticide, are linked to serious health issues, and groundwater contamination. . Monsanto and Round-up could easily slip into the bad box: big corporation, synthetic chemical compound that gets a lot of press, got to be bad right? The problem  is that most of the other herbicide compounds available to farmers are probably worse.

A field of one crop, with nothing else (ie. weeds) growing is very unnatural.  But here's the thing, virtually every crop does go through a period where it needs protection from competition in order to be productive.  But like the pristine lawn with no dandelions, there is usually a period when keeping the field "clean" has more to with pride than anything else.  The options for farmers (and backyard gardeners) is to mechanically remove the weeds using your hands, hoes, or a variety of tractor implements that cut weeds and/or churn up the soil. This uses fuel, and sometimes (as most gardeners know) does little to stop certain types of weeds that are very hearty and persistent.(bind weed, quack grass, Canadian thistle, lambsquarters, mustard, etc. etc)

There are roughly 4 different types of herbicides.  2-4-D has been  the most popular, and is found in all of the weed and feed formulations. That's because it's cheap to make, and is what's called a selective herbicide: kills the dandelions, but not the grass.  It was created in the 1940's, and its chemistry is associated with other  compounds with a far more controversial history:  like agent orange, and 2-4-5T.  The latter is now banned because dioxins were released during its manufacture.

Then there are the triazine family of herbicides, atrazine the most widely used.  It works effectively with corn, but its drawback is that it doesn't breakdown very quickly and in the right conditions can easily contaminate groundwater.

There is paraquat (gained some notoriety when it was sprayed in Mexico to kill marijuana crops). It is quick acting and effectively kills everything it touches. If mishandled though, it can be very toxic to people. It can only be applied by licensed applicators, and was banned completely in Europe in 2007.  

Then you've got the glyphosphates like Round-up, which relative to the other products in the herbicide toolbox, all of a sudden looks pretty good.  Not as safe as Monsanto claimed it was. The New York attorney general ordered  Monsanto to withdraw claims that it was "safer than table salt".  Glyphosphates were first produced in the 1970's and prevent the production of a necessary enzyme in a plant, making it very effective. It's been particularly useful in so called no-till farming which means no plowing, and much less erosion and run-off. Round-up also breaks down quickly, and is not as  dangerous  to people as many other compounds. It does contain adjuvants or additives that have proven harmful.

As so often happens with pesticides, there is division within the scientific community on the danger of all of these  herbicides. The bottom line for me is that RELATIVE to the other choices, Round-up appears somewhat safer.

What's upped the anti in the last decade is that  Monsanto has also developed Round-up Ready crops,  soybean, corn, cotton, etc that can tolerate Round-up, so farmers get to use a somewhat safer, but very effective herbicide, as little as one spray in a field, and have a productive harvest.  But (here's the rub) Riound-up  Ready crops have become so popular, that many weeds have developed resistance to it.  And now 11 million acres in the United States have these so-called "super-weeds". I'd like to say that this was an "unintended consequence", but a lot of smart people warned against superweeds years ago. And scientists are worried:  Glyphosate “is as important for reliable global food production as penicillin is for battling disease,” Stephen B. Powles, an Australian weed expert, wrote in a commentary in January.


Then there are these new concerns I touched on a couple of weeks ago:

This week another red flag came up that could have have enormous  implications. Don Huber is a respected plant scientist, and a well-known opponent of GMO technologies and products.  He's earned his opinions, and says he's found evidence of what he's calling microscopic pathogens in "Round-up ready" crops that he says are  a huge threat to the health of livestock, plants and humans.  It's the Round-up itself that he thinks is causing the problem, but obviously the development of Round-up ready crops using genetic engineering is what has lead to the huge spike, and widespread use of the herbicide.  
http://www.reuters.com/article/2011/02/24/us-monsanto-roundup-idUSTRE71N4XN20110224



 There are some "organic" herbicides out there, usually the active ingredient is acetic acid (vinegar). I didn't have much success with it.  I use my hands, a Japanese hoe, tiller, and I do spot spray Round-up on the most difficult and persistent weeds (when all else fails) and this is on a small acreage. If I had a hundred acres to take care of, I'd have to make a much harder decision.

1 comment:

  1. i think the decision is quite easy. don't use round up. we are moving backwards when it comes to producing food. with todays technologies and population (labour), the use of herbicides for effective weed control is unnecessary. even with a growing demand for food world wide, so called "organic" farm practices can feed us all. until this gets excepted by the majority of pesticide using farmers across the globe, such practices will be looked at as ineffective for large scale production. i've seen organic crops of barley, oats, peas, many varieties of wheat and even soy beans been grown without any pesticides and yields that any "conventional" farmer would dream of. round up, even if less harmful than other herbicides, does not belong in any farmers toolbox and should be replaced with common sense, hard work, and creativity.

    i think a lot of this problem falls on the consumer.

    as consumers we ask, is it fresh, is it pleasing to the eye, is it cheap and is this what everyone else is eating. for most consumers the questions end there. what the average consumer demands is impossible for the farmer to produce. does it start with the farmer or does it start with the producer? although both are responsible (for the environment, for human health, for the economy) i believe the consumer is dropping the ball. farmers are easy to please, tell them what you want and they will grow it, you can even tell them when to grow it, how you want it grown and when you want it harvested. this is happening in big-ag today, the problem is, the people telling the farmers what to grow don't have the consumers health in mind, nor the environment or our economy, the only thing they have on their mind is their pockets! and we allow this to happen.

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