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Organic Weed Management Program
John C. Simmons
Segment #1
How Does Whole Farm Management Affect Weed Control On An Organic Farm?
This presentation will come from my farm experience—my farm perspective.
I grow row crops. You may grow vegetable crops.
Different, but not that much. The way you manage a tomato or pepper or squash field
will likely have differences from the way I manage a corn or soy or buckwheat field. But,
The way we manage our soils to support healthy growth of those crops won’t differ
much at all.
Nearly all crops require good soil structure, active biology, balanced minerals, and
generous levels of organic matter to thrive and produce nutrient dense food.
This segment might also be titled: Why Rotate?
In nature, a diverse plant mix fills field space. This diversity allows species adapted to a
particular:
1) Time
2) Soil type/subtype
3) Fertility
4) Biology
5) Condition—wet/dry—cold/hot
the opportunity to fill the needs of the soil to be:
1) Covered/protected
2) enriched
3) balanced
4) stabilized
These adaptations allow for, or perhaps even promote, maximum plant growth annually,
in a wide range of fluctuating conditions.
In most cases, this process/presence is what built our fertile topsoils on top of their
rocky, parent material.
Agriculture—especially ‘mono-cropping’—short circuits this efficient system by limiting
“coverage”, or creating gaps, in one or more of these areas.
This leaves us, as farmers and stewards or “husbands” of the soil, to be the agents to
“fill in these gaps”.
Close examination of a simple “grass prairie” reveals it to be:
1) not simple
2) not just grass
Presented at Tri-State Organic IP Video Program Session II: Organic Weed Management - March 15, 2007
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Literally dozens of complementing species make up the native prairies, a natural system
which was able to support vast numbers of native bovines and many other animals.
Since many or most of us row croppers are producing feed for a subsequently
introduced species of bovines, we might do well to pay attention to the natural plant and
biological systems that supported these animals even without the benefit of all our
accumulated knowledge and science.
Conventionally practiced agriculture, assisted by manufactured fertilizers and weed
killing chemicals and insect killing chemicals has made it possible to eliminate plant
diversity, and produce crops in a mono-cultural setting. This can be seen in fields that
are in two or even ONE crop rotations—
Although labeling a practice that grows the same annual crop for years on end a
“rotation” is a bit baffling/confusing to me!?!?!?
These conventional, chemical-based systems do not promote diversity, or even
consider it as necessary or beneficial to the farming process. And, if one downgrades
the art/craft/vocation of farming to a process, perhaps diversity has no role.
I will assume that those in attendance, who have given up their evening to hear what we
have to say, are interested in or are practicing the organic expression of agriculture.
That noted, we will no longer ponder what the conventional folks are doing, or why.
Rotate, or Flip-Flop?
How many here, and there and everywhere—
Farm in a community where there is a presence of Amish farmers?
Do you notice their buggies/wagons/implements?
Spoked wheels.
Lots of spokes.
The more the spokes, the more stable/strong the wheel, the smoother the ride.
I’ve not seen an Amish wagon with a 2 spoked wheel.
For good reason.
I really don’t think it would roll very well.
More of a “Flip-Flop” kind of action.
Bumpy ride.
Pulls hard.
BUT
If we put lots of spokes in that wheel—or a diversity of crops in that rotation—things
start to roll along a bit more smoothly.
HOW?
If we examine some of the ‘services’/functions that diversity performs in our soils, we
might find these among them:
1) Different plants will exploit/utilize different mineral spectrums
Presented at Tri-State Organic IP Video Program Session II: Organic Weed Management - March 15, 2007
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2)
3)
4)
5)
Different plants will nurture differing microbiological species
Different plants will attract differing insect species—both beneficial and harmful
Different plants will attract different animals
Different plants will have differing beneficial or harmful effects on the plants—
both crops and weeds-- that follow them, or that are growing with them.
At this point, you all may be wondering why we’re on this “nature walk”, and where in
the world are we going? And what this has to do with farming and weed control??
I’ve noticed some things in the 35 years that I’ve been active in farming.
1) If I want to grow corn, I have to plant corn.
2) If I want to grow beans, I have to plant beans.
3) If I want to grow oats, I have to plant oats.
4) If I want to grow pigweed, lambsquarter, ragweed, foxtail, panicum, all I have to
do is till, and wait. Bumper crop. Never fails. Almost never.
5) If I want to grow quackgrass or Canada Thistle, I don’t even have to till!!
6) I do find, however, that I can’t grow velvetleaf as good as I used to.
Why?
Weeds, or at least what we call weeds until we find a use for them, are definitely here
for a purpose! So let’s be polite and respectful, and call them “Native Plant Species”!
Since I/we have taken control of this ship called Earth, since we’ve grabbed the steering
wheel, we have assumed responsibility to keep this ship in order!
Our soils are wonderfully forgiving. Our soils provide an elasticity or cushion to tolerate
our mistakes and our learning curve. How did they get this way?
1)
2)
3)
4)
5)
6)
7)
Plant growth
Plant decay
Animal activity
Animal waste
Animal decay
Root action
Biological activity
So, how do we KEEP our soils in this forgiving, productive, fertile condition?
Well, I don’t know about you, but I think I’ll look at the way they were formed the first
time.
I can be a bit stubborn—ask my wife, as she notes from time to time, “you can tell a
Simmons, but you can’t tell ‘em much!”—so much so, that I tend to try to “invent” things
that already exist! Well, in this case the pattern is already there to copy.
DIVERSITY
Presented at Tri-State Organic IP Video Program Session II: Organic Weed Management - March 15, 2007
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By introducing as much diversity as possible into our cropping systems, by trying to
imitate/replicate the system that built our soils in the 1st place, I believe we have our
best pathway to maintaining those soils.
What does all this have to do with weed control??
Ooooh. Now it’s “tie it together time”.
Anybody remember an old song, that went kind of like this?
”The foot bone’s connected to the leg bone, the leg bone’s connected to the knee bone,
the knee bone’s connected to---well, I guess another leg bone—but anyway.
vigorous and continuous plant growth
is connected to
Increased organic matter and biological activity
is connected to
Increased availability of balanced fertility
is connected to
Vigorous growth of highly competitive healthy crops is connected to
More efficient control of native plant species (weeds) is connected to
Less production of seed by these native plant species is connected to
Lower weed pressures over time
is connected to
Ever less weed seed production
is connected to
Easier control of weeds/native plant species
is connected to
Higher yields and quality of the crops you grow
is connected to
HOW will we do this?
KEEP IT GREEN!!
The 1st and most simple step, is to use “off season cover crops”.
1) Rye after corn or soys.
2) Clover or buckwheat or rye after small grains.
3) NO BLACK FALLOW!!
4) Utilize these non-harvest cover crop times to apply manure/compost. A growing
cover crops will hold, use, and store the nutrients and biology you are applying, and
make it available later, when your harvest crops need it.
The 2nd step, which requires a bit more management,
INTERSEEDING
Inter-seeding gives the covers a “jump-start”, keeps the soil covered consecutively,
allows for more tonnage/acre of ‘stuff you’re growing for your farm to use
1) clover inter-seeded in small grains
2) clover or rye or ryegrass or radish or a combination of these inter-seeded in row
crops
ROTATION
Rotate your harvest crops AND your cover crops!
If you grow the same crop, and or one with the same seasonal schedule,
Presented at Tri-State Organic IP Video Program Session II: Organic Weed Management - March 15, 2007
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e.g. corn/soy, the same groups of weeds/native plants will compete every year.
The few that escape will produce nice fresh seed! (and dormant seed—in case you
don’t feel like planting some year—the Earth will still be green!)
You will have more fresh/first year seed available to sprout, grow, and make you work to
control them.
The seed crop’s connected to the weed crop………..
BUT!
If you switch from a Spring planted crop—soy
To a Fall planted crop—wheat
Inter-seeded--to a clover crop—which will suppress weeds in late Summer,
Plus more suppression in the Spring—plus some free Nitrogen—plus lots of biological
activity & worms & springtails & stuff you can’t see, but it’s good anyway
Back to a Spring crop—corn—inter-seeded with clover, or radish
To an early Spring crop—oats—inter-seeded with clover or alfalfa
You have totally confused the weeds—as there are few species which will thrive in all
those situations.
PLUS
You’ve planted a crop succession which is complementary to the preceding and
succeeding crops, AND kept the soil green and biologically active, with only brief
interruptions while the newly seeded crop is establishing, for
FOUR CONSECUTIVE YEARS!! And you’ve planted 7 count ‘em SEVEN different
crops.
DIVERSITY!!
Meanwhile, you’ve also spread out your workload for planting, harvest, and weed
control across the season.
But, you say you want to become even MORE DIVERSE?!?!
Get a couple hogs.
Get some chickens.
Get a few cattle.
Pound in a few fence posts.
Unroll a few spools of poly-wire.
Harvest yet another level of diversity, and fill your freezer with yummy healthy food at
the same time!!
Sell some to your ‘less diversified neighbors’!!
MAKE IT EASY
How?
Grow things you enjoy growing.
It’s not necessarily “all about the Benjamins”.
It’s not mandatory to sell the highest gross dollar crop every year to achieve the highest
net revenue over time.
Presented at Tri-State Organic IP Video Program Session II: Organic Weed Management - March 15, 2007
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Sometimes, a “lower gross revenue crop”, like oats, will produce higher yields in
subsequent “high revenue crops”—through enhanced fertility, lower weed pressures,
beneficial ‘after-crop relationships’.
MAKE IT FUN!
Back to things you enjoy growing.
Enjoy the process.
Enjoy looking at the crop.
Enjoy the challenges and rewards of figuring out what makes this crop thrive on your
farm.
Enjoy the rewards of providing vital, nutrient dense food for people that appreciate it.
REMEMBER
There have been agrarian cultures throughout history.
(actually, I think that ALL cultures, even modern ones, are agrarian, even though they
may not admit it—cuz I think people are still eating food that is by and large produced
on farms!)
Most of them eventually starved because they failed to care for and maintain their soils
and the nutrient density of their food production.
They did however, build some nice tool sheds.
DISCLAIMER
My research/information collection is more observational, empirical, and intuitive than it
is statistical, “scientific” research as defined in our research colleges.
I don’t do ‘double blind studies’ and I seldom do ‘randomized block plots’.
I don’t have total faith in reductionist/single variable research—at least the way I’ve
seen most of it conducted.
But, I do observe full field sized experiments that I conduct on my farm, and I observe
them for years running.
Finally,
I advise you to be skeptical.
Be skeptical of everything I’ve just told you.
Be so skeptical, that you go home to your farm, and look, observe, watch, walk around
your fields. Watch where the weeds grow best and where the crops grow best. Look at
your field history, remember what you’ve planted and how it grew over the years.
Watch for subtle or dramatic differences when you grow a corn crop after a bean crop or
clover crop or alfalfa crop or pasture field or a corn crop. Watch what happens in these
fields when it rains too much, or too little, or just right.
But whatever you do, don’t take my word for it.
I’m just a farmer from North Branch, MI.
& all I know is what I see in my fields.
Presented at Tri-State Organic IP Video Program Session II: Organic Weed Management - March 15, 2007