Healthy soil and sustainable growing

["Greg and April" <gregandapril@earthlink.net>]

I have to disagree.

Nutrient loss is bad in situations where when they exposed to rain and sun.

Under these conditions it breaks down and oxidizes into forms that are not 
directly useable ( hay that has turned brown due to sun and rain is not 
better than so much straw ), but, be broken down by other means - al la 
compost pile.    Nitrogen gasses off as it is oxidized by exposure to sun.

This can be shown in the nutritional differences between hay and straw. 
By it's self, hay has reasonably high levels of nitrogen, bound up in the 
form of proteins, and has just about the right levels of nitrogen and carbon 
to compost by it's self ( ever wonder why hay will start rotting fast if 
kept wet ).

Straw on the other hand has little to no protein, but, it has a high level 
of wood sugars, that take time to break down.

You leave hay out in the sun long enough, and the majority of the nitrogen 
is lost within several weeks, leaving nothing better than a straw 
equivalent, allot of almost use less carbon - until it degrades.    Now I 
say almost useless, as there are many things that straw is useful for other 
than as a mulch, but, it will never be as go as good as a hay, since straw 
is primarily carbon.


To an extent, you are right about cattle feeding on stubble, but, that is 
dependant on many factors.    Stubble is good as a maintaince diet, in the 
winter, since the digestion process of cattle actually generates allot of 
heat, when dealing with high carbon foods such as stubble and straw.

One of the many factors mentioned above that determines on if cattle can 
fatten on stubble, is breed type.    Old fashion breeds are more likely to 
put on weight with poor forage like stubble, than modern breeds.

Another factor, is a matter of how good a job is done during harvest. 
Equipment in poor condition, or improper use of the equipment, can result in 
allot of material / food that is wasted.    I used to live on the edge of a 
farmers field, and it was not unusual to see some ears of corn, that would 
still have half the corn left on them.    Indeed in area where corn and 
soybeans are alternated on the same field, farmers buy, herbicides and 
special applicators, to kill the corn, in fields of soybeans that grew corn 
the year before.    Talk about wasted energy and food.


But how do I quantify flow of nutrients?

Over the long term.

If after 5 years the soil is healthier, and has more hummus and the other 
good things, it has a positive nutrient flow.

If after 5 years the soil is no different, then it has a neutral flow.

If after 5 years the soil is sicker, less hummus, and the other things it 
needs, it has a negative nutrient flow.

One year or season doesn't mean squat, since it is so easy to skew results 
due to unusual conditions or one time factors.    Commercial fertilizer ( 
one time factor ) are a case in point.    It's like candy to plants, they 
will take it up and show good results for a while, but, sooner or later that 
burst of energy is going to give way and there had better be something to 
support growth or eventually something is going to give away and problems 
are going to happen.    You can't keep going back and adding a short term 
solution without paying a price somewhere else.


I never said that continuous cash crops and a single fallow was sustainable. 
Given half a chance, soils will, with time, will rebuild them selves, with 
no help from us, so saying that we have to use cover crops and green 
manures, is a mistake.    The only thing that green manures and cover crops 
do is speed up an already natural process, doing in 1 or 2 seasons, that 
might otherwise take 2 or 3 years - more in extreme cases.



Just because a crop is grown, does not mean it has to be used for just food, 
or just fuel, or for structure materials or for just fodder or just a cover 
crop.    I have explained before how crops can be used for both fuel and 
food.    Eat an avocado then press the pit for oil.    Once a banana fruits, 
the main stem dies- so why not burn it, or use it to build part of a wall? 
Cherry pits from cherry operations get thrown away, why not burn them 
instead.    The list goes on of things that are tossed away that could be 
used for other purposes.


Nutrient flow has many paths - some long, some short.    Now when I say 
nutrient flow, I'm not just talking about the chemicals that plants use, 
but, all those things that turns dirt into soil.


> > In the end, the negatives and positives have to balance out to a
> > neutral or positive nutrient flow to the fields to qualify as sustainable.
>
>
> Sorry, never heard that claim made before, haven't seen anything to 
> support
> it.

Let's think about it for a second.

In it's simplest form, to sustain something means to support it.

http://www.m-w.com/dictionary/sustain

Main Entry: 1sus·tain
Pronunciation: s&-'stAn
Function: transitive verb
Etymology: Middle English sustenen, from Anglo-French sustein-, stem of 
sustenir, from Latin sustinEre to hold up, sustain, from sub-, sus- up + 
tenEre to hold -- more at SUB-, THIN
1 : to give support or relief to
2 : to supply with sustenance : NOURISH
3 : KEEP UP, PROLONG
4 : to support the weight of : PROP; also : to carry or withstand (a weight 
or pressure)
5 : to buoy up <sustained by hope>
6 a : to bear up under b : SUFFER, UNDERGO <sustained heavy losses>
7 a : to support as true, legal, or just b : to allow or admit as valid <the 
court sustained the motion>
8 : to support by adequate proof : CONFIRM <testimony that sustains our 
contention>

Now sustainable agraculture, goes both ways the farmer support the soil, so 
the soil will support the farmer.

http://www.m-w.com/dictionary/sustainable

Main Entry: sus·tain·able
Pronunciation: s&-'stA-n&-b&l
Function: adjective
1 : capable of being sustained
2 a : of, relating to, or being a method of harvesting or using a resource 
so that the resource is not depleted or permanently damaged <sustainable 
techniques> <sustainable agriculture> b : of or relating to a lifestyle 
involving the use of sustainable methods <sustainable society>


It's agriculture practice that can support it's self.

Now, if the nutrient flow is positive, in agriculture, then more nutrients 
goes into the ground than comes out.    The soil is building.    This make 
the practice sustainable.

If the nutrient flow is neutral, there is no soil build up, but, what soil 
there is, is not being used up / diminishing either.
In this case, you probably will be limited in the types of crops you can 
grow, since crop will take away nutrients as fast as they are built up. 
Since this too can be continued indefinitely, it too would be considered 
sustainable.    Once good soil is established, one only has to maintain it, 
to keep it in good shape.

If the nutrient flow is negative, then you are loosing good soil faster than 
you are building it up, it can not be sustained since the soil becomes 
poorer and poorer.

Nutrients ebb and flow with the seasons, but, as long as the average to the 
soil, is neutral or better yet, positive, the soil does not degrade, and so 
the process is sustainable.


If I harvest wood from a woodlot, in a sustainable manor, that means that I 
can do it without long term harm, so what does it matter if that wood is 
used to build a house, burn in a fireplace, or turned into  alcohol to burn 
in my tractor/truck so I can recover the wood to use in the first place?

The same thing goes for any crops in the field.    As long as the total 
nutrients FROM the field are equal to or less than the total TO the field, 
it shouldn't matter what is done with the crops, because, it is sustainable.

If I grow a crop, that needs 3 tons of CO2 from the atmosphere, and 2 ton of 
N, 1 ton of P and 1 ton of K, and it causes 2 tons of CO2 to harvest and 
process and I can return the P&K and 1/2 ton of N to the soil by way of 
animals, then grow a different crop that recovers 1 1/2 tons of N from the 
atmosphere, and puts it in the soil.    The process is sustainable, no 
matter how long the nutrient pathway maybe.

Grow a crop of grain, and put some of it aside for bad years, and the 
nutrients are not lost, they are just locked up for a number of months or 
years, yet the nutrient pathway may take a number of years from start to 
finish.    It does not matter if the nutrient pathway takes a number of 
years in some cases, as long as end result is a positive or neutral flow of 
nutrients to the soils, the soil will get no worse.

My whole point is unless we are improving poor soil, we don't have to keep 
putting more into it than we take out, for it to be sustainable, since crops 
are mostly those elements that can be recovered from the atmosphere, like 
CO2, water, and to an extent N.

It the elements that come directly from the soil, that we have to replace, 
and I can't think of a single one, that is directly used in making energy, 
since the only ones that are needed for energy are mixtures of carbon, 
hydrogen, and oxygen.

If you can think of something that is taken directly from the soil and can 
not be resupplied one way or the other from the atmosphere, please feel free 
to let me know what it is, and how it is lost in the process.

Greg H.