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Saturday, August 22, 2020

Grandpa, Bugs in the Garden, and Where To Go From Here

I was in my early teens sitting at my grandpa’s kitchen table when he announced I would be cutting down the horseweeds along the west side of his house.  “Looks like nobody lives here!” he growled.  I wasn't much interested in the job and thought the horseweeds looked just fine, but headed out to follow orders.  The weeds were impressive, some approaching two inches on the stump, and I ended up enlisting an axe to complete the task.

Turns out they weren’t horseweeds, which are technically asters, but giant ragweeds, and in more than 50 years I've not looked at one without remembering that day.  They are common as flies in these parts and grow impressively in a single season.  Just yesterday, while adding weeds to the compost pile, I realized that in a mere three months the giant ragweed were towering 12 feet overhead and threatened to overtake the pile, so I began pulling them out.  Nearly all of them broke clean near the base, its stem having been hollowed and weakened from the feeding of the common stalk borer.  The plants otherwise appeared flawless, stout as mules, racing jubilantly towards maturity.


Evolution has provided the giant ragweed with a tolerance to the borer so the plant is rarely killed, in much the same way parasites coexist with their hosts. Native oaks tolerate a raft of insect larvae which in turn feed millions of birds which then contribute mightily to the local ecosystem.  It's a beautifully functional machine, one easily disrupted by removal of a single component or when complicated by the introduction of nonnative species. 


The infested giant ragweed will complete its life cycle while the borer does the same.  To some degree we copy this strategy to manage our vegetable garden.  This spring we had a large number of squash bugs on our cucumbers. We did nothing.  As a result, the cucumber season was shortened but not before we were bursting at the seams with canned pickles.  We had earworms in the sweet corn, did nothing, and still had ample for freezing.  Our tomatoes are sick with blight but we are getting a harvest that will more than satisfy our needs.  In past years we've had issues with voles eating potatoes, maggots infesting carrots, beetles eating asparagus, potato bugs riddling leaves, but almost always we have had more than adequate harvests after doing nothing to address problems.


Today I visited a local organic grower who produces incredible vegetables as a livelihood.  He, too, has a live and let live attitude towards many common pests. Earlier this season he had the most serious infestation of aphids on pepper plants he had ever seen, but did nothing.  Within days he noticed a virtual army of ladybug larvae emerging, which it turns out, are voracious aphid predators, and in short order the problem was no more. Had he used an insecticide, even one approved for organic production, he would have almost certainly killed the developing ladybugs as well. 


In a world addicted to chemical pest control we have been programmed to reach for the pesticide at the first sign of danger.  Almost all are potentially lethal to the user and most are broad spectrum killers, taking more than the targeted species.  They are, to no small degree, responsible for an alarming reduction in insect populations worldwide, including those we rely on for pollination, including those that are fundamental to food chains and support entire ecosystems.  And both weeds and insects have an incredible ability to quickly gain immunity against chemical concoctions, forcing chemists to constantly develop new, more lethal agents in their quest for control.  It's a quest without end. 


On a typical morning I'll see several rabbits in and around the garden. Last year they took a liking to tomatoes, taking big chunks from low hanging fruit about a week before ripe for our picking.  We responded with fencing and the problem was rectified.  This year the tomato loving rabbits were back and we did nothing, lost a few low hanging fruits, and the problem is no more.  Earlier this year the rabbits were eating our green beans, so we draped the patch with chicken wire.  When the plants were larger we removed the wire and the rabbits came back and nipped a stem here, a leaf there, but from two short rows of beans we’ve canned enough for weekly meals to last a year, not to mention a couple dozen meals of fresh.  We're still picking today, the rabbits are still nibbling, everybody’s happy.


In a small way our gardening strategies help to support the local ecology.  If we had more ambition we could apply proven natural control measures and have even better results.  It’s a stretch to compare our experience with the ag industry, but a published report by US scientists in 2016 adds credence to the fact that the world’s food requirements can be met using organic methods, and in years of stress, organic yields will exceed those of conventional ag.  


The USDA Organic label has taken a hit over the years with some producers finding loopholes to satisfy label requirements while continuing practices detrimental to soil health.  In the soil is 95 percent of all life on land, up to a billion invertebrates per healthy acre and countless bacteria. There is ample evidence that modern agriculture is turning soil to dirt, destroying organisms essential to healthy function, administering toxic, manufactured pesticides and petroleum-based fertilizers in an effort to produce another crop.  The process is grinding away crucial soil components, a fact recognized by leading soil scientists. 


An improvement over organic is regenerative agriculture, which focuses on soil health and expounds the benefits organic provides.  Among it’s chief perks is massive carbon sequestration.  Conventional practices are responsible for up to 25 percent of greenhouse gas emissions.  The environmental benefits of a total shift to regenerative production is beyond measure, with every living system being positively influenced and contributions to the climate crises grand and inherent.


There is a parallel between all of this and the introduction of wolves to the Yellowstone ecosystem 25 years ago.  The cattle ranchers and elk hunting guides surrounding the park predicted it would deliver a fatal blow to their businesses but today they are still there.  That’s not to say there haven't been problem areas with cattle and sheep lost to wolves. And there are fewer elk, some whose habits have changed making the guide’s work more challenging and, for some, more satisfying.  While there will always be individuals opposed to wolves, a growing number whose livelihoods have been negatively impacted can see and appreciate the merits of having a top predator reestablished.  The ecological consequences of introduced wolves have gone beyond expectations. Reduced browsing by elk has allowed willows to return to stream banks which have attracted beavers which have worked their magic with dams.  Long lost ecosystems have been restored, diverse species have returned, and river courses have been modified which will ultimately influence geologic features.  It's a taste of the dramatic, life enriching, unpredictable repercussions of working with nature in land management.


Imagine a society embracing a principle to preserve the environment first and foremost, where a commitment to live in harmony with nature is instilled from birth, the doctrine guiding economic growth, the core of school curricula.  If some tolerable crop loss to insects, disease, competition, rodents, were viewed inevitable, anticipated, even appreciated, what would be the impact to overall ecological health? 


I'm not sure grandpa ever heard of global warming, though it was being predicted in the scientific journals of the day.  He probably didn't spend a lot of time contemplating the web of life, though he was an ardent outdoorsman.  He was instead consumed with work and earning a living, receptive to chemical concoctions that held the promise of improving yields.  He was living by the ethics of the day, putting to practice the recommendations given him, getting results favorably perceived. 


A half century later and not much has changed, other than a steady deterioration of our planet.  The window of opportunity is closing, but doesn't have to. The solutions are within reach.










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