Friday, November 07, 2008

Which Came First - Pests Or Pesticides

The Pest or Pesticide question is a lot more interesting and relevant than the whole chicken and egg argument - and one that’s easier to prove too! Whether you’re a farmer, gardener, or merely a consumer that’s not so keen on ingesting poisons, you might find the following of interest.

I know what you’re going to say - “pests must have come first, or they wouldn’t have created pesticides”. Well, as you’ll soon discover, it depends somewhat on your definition of ‘pest’, and your perspective on the world around you.

What is a ‘pest’? It’s a fairly nasty name, and when applied to a human being, suggests the person is an unwelcome irritation - someone uninvited and in your precious space. It’s a very subjective opinion, and some could say rather self-centred. When applied to an insect, the connotation is similar - we use it to describe a creature that consumes what we want to consume, and that appears to compete with us in the harvesting of our crops. We just do not like sharing our food with other creatures.

The determination to say “hands off!” to these little guys has conjured up a veritable smorgasbord of chemicals - mostly produced with tremendous energy expenditure, and from a waning supply of fossil fuels. But, despite decades of pesticide usage we seem to be losing the battle - our ‘pest’ problems are not only increasing, but the immensely complicated interactions of these insects with other creatures, and with other aspects of our ecology, are creating new problems in ever-widening circles.

First, a little historical example of how pesticide usage can increase our problems (this is just one of many you can find - and I use it as it’s one of the earliest documented, giving an indication of how long we’ve been ignoring lessons we could have, should have, learned by now…):

The Central American Cotton Disaster

The story began in 1950 with the introduction of modern forms of machinery and organosynthetic insecticides.

There were only two pests in cotton at this time: Boll weevil (anthonomus grandis) and Leafworm (alabama argillacea).

Initially, less than five insecticide applications were made per season. The yield increased from 1,550 kg/ha to 2,270 kg/ha. Great!

But, in 1955 new problems had emerged, and an increasingly heavy dependence on insecticides resulted (see below):

1950 - [Pesticides - a few] - [Pests - Boll Weevil, Leafworm]

1955 - [Pesticides - 8 to 10] - [Pests - Boll Weevil, Leafworm, Bollworm]

1960s - [Pesticides - 28] - [Pests - Boll Weevil, Leafworm, Bollworm, Cotton Aphid, Army Worm (two species), False Pink Bollworm, Whitefly, Cabbage Looper, Plant Bug]

The situation reflects the typical pesticide treadmill. As well as increasing the type and quantity of pests the farmers had to deal with, they reached the point in which 50% of all production costs were for pest control, and there were also reports that excessive pesticide use was killing the cotton plants themselves.

Cotton pest control caused other agricultural industries to suffer losses as well:

* The insecticide applications induced resistance in pests of other crops; the most serious case occurred in corn and the cultivation of corn in certain cotton-growing areas of Nicaragua became impossible.
* Pesticide contamination of air, water, pasture plants, and cottonseed-based feed concentrates, caused the build-up of high pesticide concentration in cattle. As a result, meat and milk products were unfit for export and domestic use.
* The public health office also had problems with cotton pest control. In cotton growing areas malaria became more difficult to control; due to the rapid increase of insecticide resistance in Anopheles Albimanus, the mosquito which is the malaria vector.

Higher yields were short-lived, and gave way to dramatically escalating costs. And, as you can see, also resulted in a host of unintended and expensive knock-on effects.

How does it transpire that a ’solution’ actually creates more problems? There are a few reasons, but the main two points are:

1. Resistance: Some insects always survive, and their offspring are subsequently likely to be immune as well - inevitably requiring increased dosages, or changing to a different/stronger kind of pesticide.
2. Beneficial insects: Predatory insects (spiders, beetles, praying mantis, ladybugs, lacewings, etc.) that normally keep these ‘pests’ in check are also killed by these poisons. What’s more - beneficial insects normally have a slower reproductive cycle - making it harder for a colony to re-establish itself. In contrast, the ‘pests’, or target insects, generally have a very rapid reproductive cycle - some aphids are even born with babies inside them (like one of those Russian dolls, each one comes with more inside)! These differences in reproductive rates normally work together in harmony - as although a particular aphid ‘couple’ may create thousands of offspring in a very short period of time, insects like the praying mantis, with its slower reproductive rate, still manage to keep the aphids in check since they consume large quantities of the insects over the course of their longer life span (if we don’t kill them, or send them into exile, that is).

These two points, combined, work together to keep the farmer/gardener trapped in a never ending cycle of chemical purchases that undermine the health and profitability of their enterprise.

This cycle creates a kind of ‘captive customer’ that becomes totally dependent on the products of large agribusinesses. In a bid to keep these effects from getting completely out of control, chemical companies have sought to minimise the ‘unintended consequences’ of their poisons, but to date have failed, and failed miserably. But, rather than stop to consider the underlying root causes, this chain reaction of events has instead spawned even more alarming reactionary tactics - in the form of genetic engineering.

What, then, should we do? What are the alternatives? Using the cotton catastrophe example above, where we had two pests to begin with, and used pesticides to create even more (getting trapped on the pesticide treadmill), what could they have done instead?

Anyone that’s spent any time in the field knows that insects can be attracted to a plant for two main reasons:

1) Lack of beneficial insects:

In the wild the great diversity of plant types enables a correspondingly diverse array of creatures to live within close proximity to each other. Each insect has its own housing requirements, and the modern ’sterile’ and heavily mechanised form of agriculture significantly reduces the variety of insects that can survive in a given field. In other words, the only insects that will prosper in a field of cotton, are those that like cotton! Monocrop farming removes mixed grasses, hedges, woodlands, leaf and other decaying plant litter, and presents an enormous single-course feast to a few select insects in an environment where their natural enemies are unable to set up residence. After chemical sprays have done their worst, the faster reproductive rate of pest insects allows them to rapidly rebound - and they rebound into a predator-free environment.

2) Poor plant health:

Pests do not arise because of a deficiency of pesticide in the environment any more than headaches result from a lack of aspirin in the blood system. We get headaches because of the way in which we conduct our lives, and we get pests in the fields because of the way we manage them.

The direct connection between sick plants and pest attack is a significant but under-recognised point. I remember being stunned when I saw this in action for the first time. I studied organic biological horticulture some years ago, and not long after a lesson that covered the connection between plant health and pest imbalances, I saw the evidence clearly demonstrated in my own student garden.

In my patch, amongst other vegetables, I had a couple of neat rows of broccoli - probably about 30 plants in total. One day I noticed three of the plants, only, were severely stunted in size compared to the others. These unhealthy individuals were all growing next to each other in the same section of one particular row. The cause for their ill health could have been one of a number of possibilities - but given that their neighbours were all doing fine, it was likely a very localised problem of compaction or contamination of the soil immediately below these individuals. Anyway, the sickly nature of these particular plants attracted a veritable army of tiny black bugs that were chowing down on them like nothing else. But, this is where we hit weirdsville - although each of these sick plants hosted several dozen hungry little insects, their feeding frenzy completely and entirely ignored the healthy broccoli standing only inches away! Even after a very close examination of the healthy plants, I couldn’t find a solitary bug! Being a student garden (i.e. for experimental purposes), I left the sick plants where they were to monitor the progress of these insects. The result: the sick plants withered away (with the help of these bugs), and the healthy broccoli got on with their lives without any insect interference whatsoever - and I had a terrific broccoli harvest at the end of the year. Where did the bugs go? Who knows! Off to rid the world of other sick plants I guess.

“The pests are my professors,” wrote Sir Albert Howard, founding father of the organics movement. Pest attack showed him where the soil fertility needed attention. Plants growing in fertile soil have healthy immune systems and can repel pest attack. Where this doesn’t happen, the soil is unbalanced. Correcting the problem restores plant health and the pests depart.

Essentially, pests are not pests at all. They are merely indicators of underlying problems. When we douse our plants with chemicals to get rid of ‘pests’, all we are doing is dealing with symptoms, but not the cause, of a deeper biological issue. Where we think we’re being ’smart’ and ‘high-tech’, we’re actually taking a very simplistic and narrow-minded approach. In fact - we’re being downright stupid (I mean, where’s the logic in pouring poisons onto our food?).

If your garden ecosystem is healthy and balanced, you won’t have insect problems—remember insect pests only attack sick and weak plants that need to be eliminated. As gardeners, we can learn to use such damage as a “symptom” that something is amiss and that either a specific plant or the ecosystem as a whole needs more attention.

Additionally, pesticides not only kill insects, but they, of course, effect plant health - which, in turn, attracts more pests!

Pesticides can also lead to imbalances in plant metabolism, resulting in the disruption of protein synthesis and the buildup of free amino acids within the plant. Such buildups have been shown to attract pests.

Simplistic Management

So, although we are tasked with the role of managing our gardens and farms, we’re using a very heavy-handed and simplistic approach. We regard fellow organisms as enemies (we call them ‘pests’ or ‘weeds’). Instead of developing skills of observation and recognising important symbiotic relationships, we try to buy our ’solutions’ in a bottle. Not only is this not ‘advanced’ or ‘clever’ - but it’s self-defeating. If you’ve put two and two together, you’ll have come to realise that insects are serving an important role in culling out food that would be less healthful to us, and showing us where problems in our soil lie.

The heads of chemical companies know full well that cooperating with the laws of nature will render their products obsolete. But corporate self-preservation is promoted over principle.

Unfortunately, we have allowed powerful bureaucracies to develop that are only able to generate and implement these “specialist (simplistic) solutions.” Also, it is questionable whether they are even anxious to solve the problems in the long-term, as this would deprive them of their power. It is little wonder that alternative lines of research are systematically stifled.

So, to summarise - we create imbalances by reducing diversity and ignoring soil health. These imbalances create pest problems. We ignore the root causes, and instead begin an impossible cycle of destruction - pouring poisons on our food, our land (and which inevitably end up in our water). This approach fails (doh!), but we persevere with the destructive mind set regardless - resulting in a dangerous tinkering with the building blocks of life, in the form of genetic engineering and now even synthetic biology.

Our political and economic systems, by only requiring us to examine short-term relationships, have deluded us into believing that organisms and environments can be forced to conform to artificial and not ecological laws. The tendency for many harmful effects to take a long time to manifest themselves has encouraged this attitude. However, the problems that we now encounter are symptomatic of this approach. Most of the solutions being proposed are developed without consideration for their broader or long-term effects.

The generation of these solutions to by-pass nature may be regarded simply as irresponsible dreaming. Unfortunately, we are indulging in this type of dreaming when we imagine that we can solve problems of infertile soils, pests, diseases and deficient foods simply by means of inorganic fertilizers, pesticides, antibiotics and food supplements, respectively. The proposal of these kinds of solutions is symptomatic of a science trapped in the stranglehold of inductive logic and reductionism. Adherence to these approaches is preventing us from dealing with the causes of our problems.

You can make a difference! Share this article with others, and please consider the impact of your purchases. Buy organic produce from small-scale sustainably oriented growers that promote biodiversity in their operations - and, if possible, supplement what you buy with produce from your own garden. Rather than unhealthy, tasteless fruit and vegetables (that often manage to go directly from unripe to rotten, skipping the edible stage in between), you’ll enjoy healthy ‘taste sensations’ that give you increased vigor and reduce your risk of cancer and other diseases.

We seriously need to shrink the power of these companies, and reduce their ability to control and pervert the natural systems of food production. Around 90% of the insects in the average garden are beneficial insects. Don’t kill them.

According to David Pimentel, entomologist at Cornell University, over the past 50 years pesticide use has increased 30 times (and toxicity of pesticides more than a hundredfold), yet twice as much of the harvest is lost to insects today. Chemical warfare is not only destructive to the environment and bad for your health, it’s a losing battle.

Source - Permaculture Research Institute


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