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Animal Tracks •
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Allies
and Enemies
When
I consider the abundance of life, animal, insect and
plant life, here on our farm, I realize how vibrant
our farm is. Because of our farming activity we cause
there to be much more woods-margin than if this were
unmanaged land. It seems that the transition area from
woods to field hosts the most diverse and numerous animal
and insect life. Our farm also has two distinct wetland
areas that feed the White Brook and so we also have
very well represented wetland animal populations. So
here I sit and it doesn't take me more than an instant
to decide that I am an ally rather than an enemy. After
my discussion about the periodic necessity of killing
animals this
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Toad
hiding in Woods Margin
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may seem presumptuous of me. So, let me explain. Back in
college I took two courses, Biology and Vertebrate Pest Management,
that dealt at least in part with population dynamics. The
Biology was more general and related population dynamics across
species and kingdoms even. Several basic ideas, or observations
rather, emerged. One: any population that is not regulated
(for which there is no natural check) and that has an abundant
food/energy source will continue to replicate until it exceeds
the carrying capacity of its environment. Two: at the point
at which a carrying capacity is exceeded, the population will
experience starvation that very often subjects the starving
portion of the population to diseases [epidemics for example
like Flu] that then cause the population to die off or crash.
This crash generally brings the population down to a background
level where if there are enough individuals of the species
to reproduce the cycle begins again.
Concurrent with industrialization, man has very effectively
obscured this reality. Humans have used starvation as a tool
of domination for millennia and this practice continues today.
This negates the argument of whether or not organic agriculture
can feed the world. Many impacts have resulted from man made
inputs, not only chemicals.
Since the key word in a living system is 'dynamic', we must
first accept that there are a wide range of events related
to food and energy that impact on a population. For example,
this year we have had an explosion of the gypsy moth caterpillar
population. Some areas and some tree species such as white
oak, are denuded, and therefore severely impacted. When the
first gypsy moth scourge was released back in the seventies
we used mechanical and physical interventions to control the
caterpillars.
 Gypsy
Moths Laying Eggs
Two years in a row of the damage claimed our quince trees
and initiated the decline of several chinese chestnut trees
among others. When it was discovered that Bacillus thuringiensis
[Bt] would control the population and we began yearly spraying
of the nut and fruit trees. [as a side bar, this was during
the period when I very carelessly poisoned myself with the
pesticide SEVIN and was horrified to smell the same pesticide
being aerially sprayed in the city to control the caterpillars]
I kept that up for about 5 years and then when we first moved
here [nineteen years ago] I sprayed Bt for the first three
or four years. We have seen some real impact from the caterpillars
but not nearly as devastating as those first years. Weather
has had an impact on the successive years population of Gypsy
moths. Also, I think that the very marked increase in bird
population has had an impact on the background population
of the Gypsy moths. Also, by introducing a bacteria that thrives
on caterpillars I think we see the moderating effect of that
bacteria in the environment. So, we have seen the first surge
of a population and successive years of die back and now thirty
years later a second population surge. I see similar surges
in rabbit, ground hog, racoon, squirrels, and in most animal
populations. There are populations of animals that are reaching
a critical level but have not yet exceeded the carrying capacity
of the area such as deer. It really is only a matter of time
since the population in some areas is at a level as much as
5 times higher than the ideal.
I have to say that visiting other farms that use 'conventional'
[read chemical] agriculture the populations of insects and
small mammals and birds as well as reptiles and amphibians
seems largely absent. WE struggle with weeds in our asparagus
beds and in the brambles and other berries but it gives me
the chills to go to a farm that grows asparagus and see bare
packed earth with asparagus spears growing out of it because
the chemicals used have killed everything else, and we are
supposed to accept that that is ok.
I really suggest that everyone who reads this newsletter
takes the time to read Grist for
the Mill to gain some insight on how we have
come to this point in agriculture.
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