Resist(ance)

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Since the dawn of agriculture, man has been dealing with pests denuding their crops and livestock.  Early methods of pest control included mechanical control (picking the bugs off the plants), simple organic compounds that deterred pests including essential oils, minerals, and herbs, understanding pest cycles and planting during different times of the season, and over planting which basically accounts for pest losses.

During World War II, scientists were able to refine and isolate chemical compounds and we entered an age of synthetic pesticide development.  These compounds were applied in a variety of ways and the mechanisms and effectiveness were also diverse.  During this time, and as a result of the enormous initial success of these chemicals, pest control began to focus and rely on the this single way to combat pests in the global production system.

As we entered the 1970’s a few intrepid scientist began reporting on the deleterious effects of the blanket use of these pesticides on other non-target species including humans.  Basically we were killing all of the bugs, good or bad, and this was upsetting the natural balance and order of the complex ecosystems that we farm in.  This disturbance has far reaching implications for all proximate species, but especially for those at the top of the food chain.

These discoveries led to an examination of our reliance on pesticide application as our only tool to combat infestation.  Pesticides began to be regulated and best practices recommended while the land grant universities began to develop Integrated Pest Management (IPM) procedures to lessen the amount of pesticide use and to curb the resistance organisms had been developing to these chemicals.

The 1990’s and 2000’s brought new genetically modified crops to the forefront.  These plants had certain modifications that made them unpalatable to pests, deadly to pests that consume the plants, or most commonly, the modified genes allowed the plants to be resistant to certain pesticides that killed non-modified weeds or pests.

Now, despite our best efforts to stay one step ahead of nature, we are faced with resistance developing around the world and in many different species.  The reason for this lies in the biology of most insects.  Most of the major pests tend to be quickly reproducing and on the bottom of the food chain.  Reproducing in great numbers has a survival advantage for these animals as they are supported by their ability to suffer high mortality while still having enough individuals to find suitable partners and mate.  This high rate of reproduction is exactly the mechanism that promotes resistance to our pesticides.

Let’s say that there are 100 bugs on a plant that you are going to spray with your pesticide.  You target the one plant and apply the chemicals.  The compound does its work and you get a 90 percent mortality.  That’s pretty good overall but what happens next is where the problem of resistance lies.  That ten percent who survived the treatment are naturally resistant to the chemical.  Now that they are still alive they can breed and even more of their offspring are resistant.  This process continues, if you are still using the same chemicals, and the resistance increases.

This is where Integrated Pest Management comes into play.  IPM is an ecosystem-based strategy that focuses on long-term prevention of pests or their damage through a combination of techniques such as biological control, habitat manipulation, modification of cultural practices, and use of resistant varieties.

Like most things I talk about when it comes to farm management I like to think about pest management from a holistic point of view.  Now I know that I have lost some of you by just mentioning the word holistic, but bear with me.  Holistic management involves considering and cataloguing all of the different management units and resources so that you are never making changes to one part of the system without considering its effects on the other parts.  For example, if we decided that we wanted to encourage more frogs to reproduce in our farm ponds because there are an excellent natural fodder for our duck flock, we decide to enlarge our farm ponds.  We dig the pond out but at the same time pull up most of the vegetation on the sides of the ponds.  Without the shade from the pond-side plants, the water temperature climbs too high to support the natural fish prey of the frogs living in the pond.  This causes a fish die off which in turns leads to a food shortage for the native frogs.  We have actually modified the environment to be less conducive to the frogs than when we had started.  Holistic management would guide us in considering the many other factors that may affect the frogs’ mortality and the other ways in which we could manage for their success.

Holistic just means considering the whole system.  Far too often we are enamored by the quick results of certain chemicals and techniques without being able to see the other consequences of these actions.   So what does this have to do with you, my general reader?  In all farming systems, whether you are nurturing row crops, or growing up goats, there is an advantage to stepping back and considering the whole picture.  I can guarantee there is always a better, cheaper, more sustainable, and exciting way to do something on your property and utilizing holistic management guidelines may help you find how those things can work in your favor for your system.  Below is a link to the Holistic Management Institute which has many publications that can begin you on your journey of full system analysis.
https://holisticmanagement.org/

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