Rejuvinating Old Paddy Land

[Smithson]

We are looking to purchase 6 rai of old paddy land. Talking to the owner it seems for the past few years it has only been used for grazing buffalo.

The soil is sandy and doesn't look in great shape. Any suggestions for improving it? My thoughts were:

- Turn the soil adding burnt rice husks, manures and coco inner husks.

- Plant legumes, such as cow tamarind and sun hemp.

- Keep the buffaloes out

The area isn't huge, so I'm not worried too much about costs, but the method would need to be simple enough that a Thai farmer could manage without supervision.

I would like a 'forest garden' and wouldn't be looking to return a profit. Any suggestions, feedback?

.

[IsaanAussie]

Hi Smithson,

Have a look at this site http://www.soilfoodweb.com/sfi_approach1.html it may help. One thing that you may wish to think about is the effect that flooding the land will have on any humus you add. Recent studies are suggesting that a lot of the microbic life is killed off if the land is under water too long.

IA

[WatersEdge]

Hi Smithson,

Hi IsaanAussie,

By furrowing a paddy field as though you are going to plant Cassava,

you allow available water to percolate while a large portion remains damp but not waterlogged.

I built a paddy perfect level for my hog barn waste, benched at 0.40 m below hog floor level.

Then cut deep furrows on 1 meter centers, with the dirt ridged as sharply as it would stack.

Every day we flushed a lot of water out, letting it carry hog waste evenly to all points

The water wicked upward on the furrow perhaps 10 cm, then sank into the tight clay,

so that every day there was no water standing.

We could have disposed of a lot more hog waste on the same paddy area

with the same amount of water.

I used excessive water to uniformly distribute limited hog waste.

I planted Pumpkin at the upper edge of the damp soil on the side of the ridge,

around 10 cm above max water level.

They did fabulous, able to get all the water they needed without ever being flooded.

After a time, there would be accumulation of solids in the furrow,

and of course rich soluble nutrients deep into the soil

at which point you pack the trench full with dry mulch and reverse the roles.

Where the ridge was now is the furrow

The starting material on this new terrace was freshly excavated hilltop carried from nearby.

The worst possible planting conditions, hard crusted clay.

On a different model for rainfall retention here at the house

I've used a 1.5 meter on center distance.

I like that better, because it allows you to dig a trench around 50 cm deep,

with the bottom of the trenches on perfect level with each other.

This permits the ground surface to be a little irregular.

As you dig the trenches, you can dump the dirt in the surface low point,

so that over many years a sloped field will be more flat.

With the soil slowly eroding from the ridge down into the furrow

blending with whatever vegetable matter is below,

you built a mat.

Since I have a steady supply of coconut fiber,

I've packed one of these trenches all the way to the surface with fully leached coir.

pouring liquid clay slurry over it as I fill.

The coconut absorbs 4 times its weight in water, releasing it as the plant needs it.

Starting out it consumes a lot of Nitrogen, I'm still experimenting on the long term effect.

Like any new wild idea, the results take time and observation.

I predict that a deep rooted plant will work fabulously,

but shallow rooted plants will find themselves lost in the great expanse of coconut trench.

They will need to be planted in the soil at the edge of the trench.

The beauty of a coir packed trench is that you don't lose the surface area of the trench in the field. My early experiments with level retention trenches were great, except that I couldn't plant anything there. That limitation is now eliminated.

If one was planting trees, It would be fun to dig a deep trench

perhaps a meter deep, packing it with coir layered with soil

then planting the trees in the undisturbed soil alongside.

I dare say the trees would have no shortage of water all the way through dry season.

Don't try this with Tamarind, they actually need water stress to set fruit.

It may seem a daunting task to source that much coir,

but I've hauled going on 30 tons since last August, a pickup truck load about every three days.

[drtreelove]

Good suggestions from IA and WE. I would add, thanks to Rice555 in a discussion on the organic sub-forum, I have discovered a new look at an old science, a good approach to soil testing and soil mineral amendments.

http://www.soilminerals.com/

Soil analysis will give you a good picture of what you are dealing with in Cation Exchange Capacity, Soil Organic Matter content, pH, major and minor mineral content and balance, etc. Prescription amendments based on the soil test will get you closer to optimum growing conditons, nutrient availability, drainage improvements, etc. Most people use guess-work or general principles and applications. I believe the soil test approach is superior. Yes, it's an expense, but worth it IMO.

Follow directions on the website for soil sampling, get the basic analysis run at a local ag university (MaeJo U soil science dept or Chiang Mai U do it for about 1000 baht), email the results to Michael Astera at soilminerals.com and for US$45 via PayPal he will give you an interpretation and prescription and coverage rates for what's needed. The challenge will be sourcing the materials in Thailand, but I believe most components will be available. You can email him back with what you can obtain locally and what you can't and he can possibly make adjustments/substitutions.

Read his e-book 'Ideal Soil' and you can begin to do your own interpretation of the soil test and prescriptions.

The Soil Food Web outlook is an important component, but only one part of the picture, and not enough in my opinion to cover all the bases for soil and plant health.

[Smithson]

Thanks for the advice from everyone, it's all very helpful. I haven't posted here because we weren't sure about buying the land, but now it looks like it will go ahead.

The plot is only 6 rai, have of which we will plant with giant timber bamboos, mixed with trees (as this bamboo grows better in these conditions).

The soil testing and analysis sounds worthwhile as it takes a lot of the guesswork out. I'd be interested to hear others opinions on this. Discussing with WE, he suggested fertilizer requirements for bamboo were similar to those for corn. Is this what I should use for a guide for the ppl doing the soil analysis.