Tropical Soils

In our last post, we recognized fully how the Indian cultures of the deep Amazon actually achieved the incredible soil fertility still extent to this day. This also informs us on what practical methods now become available for all tropical soils world wide. This is incredibly important.

The vast majority of tropical soils are currently farmed if at all using primitive slash and burn agriculture. And all attempts at any other form of agricultural culture collapses from soil exhaustion. Any exceptions require a huge labor and energy input for the culture to be sustained. One only needs to think of rice paddies. The other major exception is tree based mono culture which is able reach deep into the earth for its nutrient supply.

The rule is still slash and burn over vast tracts of semi accessible jungle. And population pressure has turned this into an unsustainable free for all throughout the tropics that devours the best intentions of aid givers. I have reports from the Philippines, in particular, that illustrate this very well.

In one locale, $30,000,000 in foreign aid was used to reforest huge tracts. Five years later, it was all cut down to produce cooking charcoal for local markets. In this same locale, these highland fields will produce exactly one crop before it goes back into fallow for fifteen years. And we expect a settled village life to emerge here? It is no different anywhere in the tropics.

Burning releases soluble nutrients that that are simply washed away to soil depths inaccessible for short rooted crops. The Indians used to do this in the eastern woodlands with the same tragic results. What saved European agriculture was the fact that the nutrients only migrated several inches and could be returned to the surface with a plow. Most of those soils are severely depleted after a hundred years or so and then require aggressive refertilization.

Now we suddenly have a protocol that solves this problem and has been test driven for hundreds of years in the worst possible conditions in the central Amazon. And the only modification we need to slash and burn is to add a wood chipper and a movable Carbonizer.

One would start by using the produced carbon to prepare a field representing perhaps around ten percent of the area cleared.

The whole field would then be cropped, including as much corn as possible. Again the stubble will be carbonized and placed on the prepared field. The rest of the land can then go back into fallow while the carbon enriched field is operated primarily as a corn field with the ongoing recarbonization.

It should be clear after five years how well this is working out and what are the best ratios to use in the initial field preparation. One then proceeds to convert over the balance of the land in phases to this new culture.

The main point that clearly comes out of this is that the labor is already in place to do this with a modicum of instruction. After all they do cut the brush and trees down in the first place before it is burned. Adding the simple step of gathering and chipping is hardly a chore compared to cutting this stuff down in the first place. And there would still be ample debris left to fuel the normal burn on these fields.

One aspect of the labor issue should be mentioned that is very much in corn's favor. That is that the root ball of a mature corn plant is very shallow and in a prepared growing bed, child's play to pull out. Thus if machines are not available to harvest the stalks, a crew of workers can clear a field easily. That is why I realized that the ancient Indians only had to lay up windrows twenty feet apart. It requires minimum walking and the use of hands only. Even children could do this while the adults threw on dirt. A few days work and your family's field is ready.

What we have is an amazing corn culture that facilitates the sustainable development of all well watered soils and potentially sequesters around a ton of carbon per acre per year. Fine tuning will ultimately minimize if not even eliminate the need for chemical fertilization since most such fields will be augmented by wasteland carbon carrying nutrients drawn up from deep soils.

We have also discovered how to feed another ten billion people while improving the biosphere.

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