Reasons to
avoid mosquitoes are not difficult to find.
Their bite does not particularly hurt, at first anyway, but even one
bite can become an itchy nightmare, and they seldom bite singly. In addition to being a nuisance, these bites
carry numerous diseases, not the least important of which is the dread West
Nile virus, frequently the cause of an extremely uncomfortable illness, and too
often fatal.
So,
mosquitoes bad, no mosquitoes good, right?
Here is the
point in a Big Myrtle posting where you expect us to whip out some kind of
scientific explanation for why it is important to keep in balance, yada yada
yada. If that is what you are waiting
for, you are going to have to keep on waiting.
On the subjects of fire ants and mosquitoes, we are not objective in the
least. We hate the little blighters. And at least some scientists agree with us –
a July 2010 article in Nature
entitled “Ecology: A world without mosquitoes” posited that there would be
minimal impacts if all genera in the family Culicidae
were eradicated. We don’t hold quite so
extreme a view, but still, it’s nice to imagine.
So… what to
do about them?
More on fire
ants in a later posting, as they are the more difficult pest with which to
deal. Mosquitoes, for a resourceful
gardener, are actually one of the easier problems to solve. All it takes is some resource allocation (and
no, we don’t mean money, though you may have to outlay some of that), and the
sweat equity necessary to put things in their proper places.
The secret
to fending off mosquito attacks is partially to be found in the advice given by
practically every municipal government in the world – limit the availability of
standing water in which the creatures breed – but more importantly to be found in limiting the spaces in which
mosquitoes are comfortable. Yes, the
mosquito has a life cycle, and interrupting the larval stage of that cycle will
reduce the overall population, but you still need to be prepared for the
dangers represented by adult mosquitoes on the prowl, and the best way to do
that is to design your living spaces in such a way as to make them feel
unwelcome.
What do we
mean by that? Well, stop and consider
how the mosquito spends its day. A
creature that small would rely very heavily on one sense above all others –
smell. Sight, they have… but they do not
primarily rely on it to discern friend from foe, food from fen. No, they spend their time sniffing out either
the sweet, sticky smell of plant nectar (particularly of smoother grasses), or the
telltale odor of mammalian perspiration.
There are a
few other chemical markers they track, notably carbon dioxide, but the chief
thing to note is, it’s their sniffers you need to attack if you want to make
them leave you alone.
And the
easiest way to mess with their sniffer is to create an environment in which
their sense of smell is completely overwhelmed.
A pretty herb garden is not just pretty, and it’s not just useful for
natural medicines or for culinary delights, it is also your first line of
defense against biting insects.
As it turns
out, you are orders of magnitude less likely to bit by mosquitoes when tending
a bit of garden comprised of pungent plants like rosemary, basil, catnip, sage,
lavender, oregano, fennel, anise, mint of all kinds… the smells simply overwhelm
the ability of small insects to differentiate plant from person. And if your garden is not monocropped, but is
instead a healthier random hodgepodge, even better. The more interspersed the smells are, the
greater the effect.
We had read
about this phenomenon before, of course, being English literature
baccalaureates who don’t’ believe something exists unless it is in print, but
experiencing it firsthand has lent us an air of expertise on the subject we
might not otherwise have acquired. We
noticed several years ago that we were far more likely to get bit in the
backyard rather than the front. Numerous
experiments reduced the possible number of variables to an acceptably low level
to allow us the rather novel conclusion that, by jove, those organic gardeners
know what the heck they are talking about.
The usual
approaches to the art and science of repelling mosquitoes, of course, are the
familiar bug sprays (both those designed to kill and also those designed to
repel), in addition to the use of excluding or filtering spaces with screens
and netting. The limitations of these
approaches are telling – sprays designed to kill end up poisoning more than
just the bugs being targeted, while sprays designed to repel end up wearing off
(particularly in water); and screens and netting, of course, limit your
movement in addition to the movement of the bug – plus, once a hole in your
armor is found, the bugs will simply pour through in an unstoppable wave.
The
advantage of smelly herbs is that they are there year round (particularly the
perennials, such as rosemary, lavender and oregano), and just so long as you
plant enough of them all around your yard, they are effective all the time,
everywhere, rain or shine. If you happen
to have a backyard pool, the effect doesn’t wear off after a dip, either.
And then
there is this ancillary factor – we think of mosquitoes as “blood suckers” but
the truth is that mammalian blood is only one part of their diet; mosquitoes
mostly thrive on nectar from their favorite plants. A grassy field is their favorite abode (watch
a squirrel or rabbit run through an open expanse of unmown grass and see the
midges fly up from the ground if you want visual evidence). By replacing their natural roosting and
foraging grounds with pungent herbaceous plants which provide neither food nor
shelter, you can reclaim your territory, enjoying it more on every level
conceivable.
There are
other advantages to this approach as well, most notably the idea that
interspersed herb beds are an excellent exemplar of the forest gardening
approaches favored by permaculturalists.
Edges are the microecological hotspots, and permanent herb gardens form
an exceptional intermediate layer in this multilevel canopy approach to
gardening.
We get
requests for advice from all over, and one of the more common (and eternally
surprising) questions is “How do you keep your rosemary from spreading too
much?” The answer, of course, is “Why
would we want to stop it?” As far as we
are concerned, the rosemary, lavender and fennel can spread as far as they
like. Not only do we enjoy the smells….
we know from hard earned experience that mosquitoes don’t.
One final
note, about that standing water
idea. We have heard numerous people
comment on our rainwater collection ponds, saying they would be too nervous
about mosquito control to attempt something of the sort. This is a common misconception – the
“dangerous” standing water to be worried about is in open containers – old
tires, uncovered buckets, clogged gutters and the like. As with so many things, manmade structures
are the worst danger – places where mosquitoes might thrive, but none of their
natural predators can get at them.
In a natural
setting, there are few places less hospitable to mosquito larva than a well
tended garden pond – in addition to natural predators such as fish,
dragonflies, turtles, lizards, frogs, crayfish, and gude kens wha else, a pond tended by a careful gardener experiences
enough maintenance that any mosquito infestation can be readily observed – and
dealt with. Baccilus thuringiensis dunks are available at practically every
garden supply store, and even these may not be necessary, provided enough
natural flora and fauna exist to keep larvae in check.
And, as it
turns out… our ponds are not the source of the few mosquitoes we see each year
anyway. Scientists have a word for the
nesting preference of the truly dangerous mosquitoes – “phytotelmata” is a
fancy word for “natural reservoirs on plants” and it is here that the
mosquitoes carrying disease are most likely to be born.
Water
standing in the stumps of trees, or in standing water in a clogged gutter, or
in open buckets, old tires lying around with water in them, or open sewer
drains are far more likely to be the cause of a rampant mosquito problem than
ponds, creeks or even drainage ditches.
This is both because the presence of natural predators is inhibited in
these out-of-the-way breeding grounds and also because these places are also
the best environments for disease-causing bacteria and viruses to thrive, out
of sight from cleansing ultraviolet radiation from the sun, which kills
virtually all bacteria and viruses, given enough exposure time.
For those
things you can control, like any containers on your own property that you can
either remove or clean, or gutters on your own roof that you can clear of
debris, the solution is straightforward:
clean it, clear it, remove it.
For those things you cannot control, like the cleanliness of your
neighbors’ yards or gutters, the solution is smelly herbs. Areas of your
property where there is likely to be an incursion of visiting mosquitoes should
be overplanted with every variety of pungent plant you can imagine – go
wild. A rosemary hedge can be a symbol
of health and wealth, and a talisman against irritation.
So, as you
prepare for summer, you can either get ready to smell like deet, or you can
take Myrtle’s advice, and decide to smell like a lovely bouquet of mint,
lavender and rosemary. Our approach is
more pleasant, we believe, but to each their own.
Happy
farming!
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