Greetings all. It's 97 outside with a heat index of 107 so peach
picking has long since halted for the day. I would like to offer my
take on recent topics: OP residues, obesogens, IPM vs. Organic, etc.
I wholesale IPM fruit to 2 large organic CSA's in the Atlanta area
supplying approximately 450 families with fruit each week. I have
quite a bit of experience convincing the organic buyer that IPM is a
better production system for tree fruit, especially from the
standpoint of global warming. Spraying sulfur every 3-5 days and more
often after every rain event uses at least twice as much fuel as a
14-21 day interval with conventional protectants, and this is not
insignificant when you're pulling a big airblast sprayer. I know of
only one organic apple grower of consequence in the southeast. Since
he can't use any herbicides to reduce weed/grass competition, he
grows on M7 rootstock, which means he needs higher water volumes
resulting in even more fuel required to spray his acreage. Of course
sulfur does make a fair miticide but it reduces predatory mites along
with the bad guys, which makes it a somewhat addictive spray program.
"Chemical mowing" with a low rate of glyphosate, which greatly
reduces mowing of row middles, is not permitted under organic
production, so more fuel is required to keep grass middles at a
height that doesn't impede airflow through the trees. Here in the
southeast, where fescue can grow 10 inches in one week on humidity
alone, chemical mowing can save a lot of fuel. To calculate offset of
carbon emissions, the carbon output of producing 6.5 oz. of
glyphosate, delivering it to the farm, and applying it to one acre of
row middle (which is more than one acre of orchard) would have to be
compared to the carbon output resulting from the production and
consumption of enough diesel to mow the middles for a 6 week period.
Don't forget grease for the mower, new blades, etc.
Spraying urea in spring/fall to reduce sources of scab inoculum is
not permitted under organic production, even though urea is an
artificially produced organic molecule and this practice would be a
great addition to organic protocol if it were allowed. It might even
allow a reduction in the number of cover sprays. In IPM this
reduction in scab inoculum will hopefully allow SI's and strobi's to
remain effective enough to stretch out our spray intervals, at least
in regions where resistance is not common.
I recall a recent article in Good Fruit Grower, quoting a researcher
at WSU who stated that the majority of CO2 output in agriculture
comes from tillage. This is a very simple equation: any time you turn
the soil and expose organic matter to the atmosphere it outgases CO2.
If you're tilling under trees, or more likely grapes, you're
releasing CO2. If you're tilling between rows of vegetables instead
of relying on a well calibrated rate of pre-emergent herbicides,
you're releasing CO2. While you're tilling, your engine is releasing
CO2 along with a lot of other nitrogenous compounds that reduce air
quality. There is no free lunch in this equation. Depending on your
soil type, climate, and herbicides used, there may or may not be any
environmental consequences or lasting residues from a well timed and
properly applied herbicide program. I say this because here in the
southeast, solar radiation, high temps, humidity and rainfall cause
pre-emergent herbicide programs to break down quickly in all soil types.
In IPM tree fruit, a properly maintained herbicide strip boosts
levels of predatory mites and decreases pressure from plant bugs and
borers as well. Release of CO2 from tillage is fairly consistent. Say
what you may about the large amount of chemicals and nitrogen used by
the big corn growers in the western US; they have managed to lock up
a lot of carbon with no-till and strip-till, and ironically enough,
they have managed to increase the organic matter of their soil to a
greater extent than the traditional practice of turning under organic
matter with tillage. In their system, herbicides, worms, fungi, and
bacteria have replaced and surpassed tillage. The corn/ethanol
equation is not so well balanced, but their system proves that good
soil practices can sometimes be counterintuitive.
It IS possible to use herbicides (and all other crop protectants)
without polluting the environment. One state official who monitors
water quality in our area told me that he doesn't find agricultural
pollutants in the river systems in our area; the principal sources of
pollution here are from urban pavement runoff, herbicides and
fertilizer used in landscaping/turf, and sewage overflows from aging
and overloaded waste treatment plants. It is purely easier for the
media to make a broad generalization and occasionally blame growers
for all that ills our environment, and now apparently for the extra
bulge that occupies our midsection.
Farmers do not have a loud voice in our defense. We are the 1.5% of
the population that feeds the other 98.5% and people no longer
understand our craft. Our GPS units and spray controllers no longer
fit in with the stereotype of overalls and chewing tobacco, but to
the modern media it is the guy with the overalls who is applying the
chemicals, and he can't possibly be educated enough to know what he
is doing, so he must be poisoning everyone by spraying 2 oz. of Flint
on his apples.Shock journalists would have the public believe that
every crop protectant applied during the growing season is still
present on or in the fruit at harvest, or that small amounts of
chemicals do not break down into benign compounds in the environment.
Ironically, chemicals break down faster at higher temperatures so
global warming actually assists the process.
I have grown vegetables organically and conventionally, and tree
fruit with varying degrees of IPM, and I think the best system is not
found in the extremes of conventional vs. organic, black vs. white,
but in the gray area that most of us tread as growers. Organic
systems become locked into a "thou shalt not" mentality that entire
crops are sometimes lost or suffer reductions in yield under extreme
pressure. Conventional programs were, in the past, locked into
routine calendar sprays later in the season that were sometimes
unnecessary. The version of IPM I sell to the wary buyer is based on
the core of my spray program: be very thorough and aggressive early
in the season, use effective chemicals through early cover sprays,
and then you can gradually back off, get softer, and cease spraying
well before harvest. Most of us do this. As far as OP's go, I use
Lorsban at dormant, a couple of Imidan sprays at petal fall and first
cover, and that's it (no dogwood borer pressure here). I would find
it difficult to believe that OP residues would be detectable on the
fruit 3-4 months later. Ditto for SI's and neonics used through 1st
or 2nd cover. There is also a remarkable invention called a brusher
that can finish the job.
Most of the chemistries applied during later cover sprays is "soft"
chemistry with newer products such as rynaxypyr, spinetoram, rimon,
etc., but the public has not been told that our industry is
constantly becoming softer in chemistry or that application rates of
these newer chemical per acre is extremely low. Rynaxypyr for
cucurbit crops (Coragen, vegetable version of Altacor) has even be
sprayed directly on beehives during tests, with no losses. Granted,
98% of the public was asleep in chemistry class, and journalism
majors were no exception, but here again our voice is silent. We tell
the public our product is safe with very little explanation as to
why. I usually try to explain the pheromone traps, degree days,
mating disruption, and the fact that my fruit hasn't been sprayed
with anything for at least 2 weeks before harvest (peaches in July, I
try for 3 - 4 weeks after that), and they realize that I am making an
effort to produce a safe product. It helps if the product is a Pink
Lady that tastes so good they can't refuse. Don't wear overalls and
chew tobacco while you make this explanation.
I'm lucky enough to grow in an area with minimal lepidopterous
pressure (but with enough fungal/bacterial humidity problems to
compensate) and I realize that is not the norm. That is the entire
point behind the late season "read and react" approach of IPM. Every
orchard is a different ecosystem and good systems are flexible enough
to compensate. I use all of the above mentioned chemicals (not
necessarily in the same season), usually one Sevin spray for Japanese
beetles, and I still have a good balance of predatory mites and
beneficials, with evidence of mantid and Assasin Bug egg clusters
during dormant pruning. Solitary digger wasps nest in the herbicide
strip, a few birds build nests in peach trees every year....the
modern orchard is hardly a dead zone. As for my lack of lepidoptera:
there are no other orchards within 60 miles of mine, so I presumably
have reasonable control over resistance management via good MOA
rotations that are not affected by a neighboring orchard with a
conflicting rotation; I am in an area with imported fire ant and have
witnessed an increase in tufted bud moth damage when I eliminated the
fire ants for one year; I have an abandoned concrete silo with a
missing roof panel harboring a huge colony of chimney swifts that fly
at dusk when moth flights are taking place. These are possible
controls. Is funding available for the "Abandoned Silo Initiative?"
Try removing one roof panel, preferably not with a 98 MPH hurricane
like mine, and see what happens.
Organic nitrogen and soil building is a valid concept that I have
tried for many years, but I have consistently produced a better apple
with Calcium Nitrate so I haven't revisited the cooked chicken litter
products. Our growing season here is very long and trees can break
terminal bud and start growing again all the way into November with
too much residual nitrogen, especially in clay soil. I do think
compost would be useful but have no good source for a consistent,
repeatable product. Pure organic methods will not feed our
population with the number of growers shrinking every day, but if our
civilization wants to reinvent its waste footprint, facilities
combining sewage and garbage disposal to produce fertilizer should
probably become greater in number if they can conquer the repeated
spontaneous combustion problem exhibited at a nearby experimental plant.
I stand by my assertion that while organic systems have some merit,
mainly in nitrogen management, they cannot claim to be superior at
sequestering carbon or in conserving fuel. Given the fact that our
industry gets so much bad press, and that congress has recently
mentioned tax credits for agricultural carbon sequestration, I think
a comprehensive comparison of CO2 output from organic and IPM is in
order. I would propose a multi-university study employing grad and
under grad students to analyze inputs from different orchards and
calculate CO2 output, fuel usage, and possible impact on global
warming. These studies cannot be cursory in nature; in the previous
example of sulfur sprays, one would also have to take into account
increases in soil acidity, the transportation and application of
additional lime to offset acidity, which would require consideration
of the distance from quarry to farm. Application of Calcium Nitrate
(no increase in acidity) vs. other nitrogen sources would be another
example of this type of computation, and would involve the cost of
shipping Calcium Nitrate from Norway. In calculating tillage vs.
herbicides you would have to factor in production of steel to make
replacement implement points. The list goes on, and it would be best
to involve as many minds as possible so as not to miss any relevant
inputs. Selecting orchards in different climates and geographical
areas is obviously vital to the process. I have a good idea in my
head as to the key universities with good fruit production
departments that should be involved, but I won't name them here
because I don't want to tick anyone off and again, the more minds the
better. At least when it comes to global warming we do have the means
to accurately compare organic vs. conventional.
As far as pesticide residues go, perhaps it would be helpful if
growers could discretely submit fruit samples to see what residues
are present. Give the industry a chance to police itself and for the
grower to see where they stand in this regard. If systemics are
assimilated by the fruit it would be helpful to know at what levels
they are still present at harvest. Debating the safety of minute
residue consumption is a moot point. There are some consumers who are
so terrified of chemicals that they will avoid anything but organic.
I find most buyers buy initially with their eyes, but repeat sales
come from the palate. Frankly, the supermarket apples here are so bad
that I have no problem selling at high prices.
As for kaolin, I tried it for 3 years mainly for sunburn reduction
and as a Japanese beetle repellant. It did not work well for either
purpose and I consistently had a poorer finish at the end of the
season. I theorize that systemic fungicide applications on top of the
kaolin could not reach the fruit and were rendered useless. It took
longer for the fruit to dry every morning and that might have been a
problem with our heavy dews. It remained persistent on the fruit
through harvest, even when use was discontinued in early June. It was
very difficult to clean the apples and a brusher can't reach around
the stem. I got tired of explaining to the customer that the
unsightly residue on the apple was not a pesticide but was a nice,
safe organic product. It also contains some aluminum, which may or
may not be a safety factor depending on whether aluminum is actually
harmful in the diet. Based on my experience, I would hate to have a
production system based on sulfur, kaolin, and Serenade.
Also, the sooty blotch/flyspeck complex is not merely cosmetic. In
refrigerated storage it slowly moves deeper into the skin and
eventually renders the fruit unsalable, especially on thin skinned
apples with high brix. Storage/shelf life is why the industry demands
a more perfect fruit finish. Given time, even minor cosmetic problems
become storage problems, in some cultivars more than others. If the
fruit is held at 32F and is going to be consumed within a couple of
months it doesn't matter.
As far as obesogens go, they have been theorized and may be a
reality. Recent attacks on the liners of soda cans would have you
believe that it's not the sugary soda that causes obesity, but the
plastic liner in the can. It would be difficult to get fat eating
caramel covered apples, much less plain fruit with minute residues of
a theoretically fattening compound. This is a blatant example of
irresponsible journalism. US Apple, on the other hand, has done an
excellent job of collating numerous statistical studies showing that
apple consumption can help with weight loss, cancer prevention,
asthma prevention, reduction in mental decline; statistics show that
they are one of the healthiest foods on the planet. None of these
studies identified organically grown fruit vs. conventional. Since
the studies took place in many different countries, and were carried
out by different groups over different time periods, we may surmise
that the population base covered in the studies ate the average
apple. So these health benefits are probably from a minority of
organic apples with a great majority of conventional ones thrown in
the mix. Bottom line: apples are very good for you and the best ones
to eat are the ones you will eat the most.
My crew and I have been tasting a lot of peaches while
picking--peaches that were possibly sprayed with an obesogen a month
ago. Oddly enough we have all lost weight in the 90 degree heat. And
for one of my buyers who used to be adamant about how the Plant
Variety Protection Act would ruin the world, one bite out of an NJF16
peento changed her mind. Long Live PVP!
This was longer than I intended. Thanks for your patience.
Brian Heatherington
Beech Creek Farms and Orchards
Georgia, USA
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