Land Reclaimation

[aletta]

Is it true that eucalyptus wood fetches about 7000 baht a ton?

[chownah]

Good thinking--one should know the way out of a room before one enters it.

I do not like the ricepaddy idea -trending more towards vegetables /produce  growing . If worked by machinery the soil would have to be pretty clesr of stumps /roots etc,but if mainly/partly worked by hand that would not hamper the procees too much, But how serious is the problem with root extracts poisionig the surrounding area? Once the tree is dead ,is that still a problem?

<{POST_SNAPBACK}>

I have no direct experience with eucalyptus but I have alot of experience with organic gardening and have read extensively on the subject. If you want hard facts about dealing with eucalyptus removal I don't think you are going to find it here....and even if you did would you trust the source? If I were going to invest alot of time and money on this type of project I certainly would not base my decisions on what people here (myself included) say.....getting a link or other source of info is the best you can do here.

Having said that I'll give you my thoughts on eucalyptus roots. Since eucalyptus roots are organic they can be broken down by decay processes. I have never heard of some plant or animal produced material which did not break down naturally. The question is how long will it take. By using organic gardening/farming methods you will radically increase the rate at which this happens compared to the natural processes. The same thing can be said about the toxins that are in the leaves or that drip off of a tree in the sap.....all of these can be broken down with natural decay processes which can be done more rapidly with organic gardening/farming techniques.

Learning about organic gardening/farming techniques will take time and practice....the same thing is true of learning non-organic gardening/farming techniques. Many times people who have little/no experience in gardening/farming are interested in doing some project of this type and they go out and look for information that will assure them success in this endeavor. This is like trying to learn how to oil paint and thinking that the first thing you will do is a masterpiece. Farming is not a simple thing....it is an art and a science....best to learn to walk before you try running.

<{POST_SNAPBACK}>

There is no big deal in reclaiming ex eucalypt country,most of the farmland in oz was once just that,only these days we use dozers instead of *clydesdales.*

If its standing forest you just push every thing over with a dozer then you rip the roots up with a brush rake (like a big rake instead of a dozer blade) this takes the roots and leaves the soil, pile the debris in rows or heaps to dry ,where it can be salvaged as firewood (added income) or simply burnt in situ when dry.

Meanwhile you plough the land ready for sowing,some prefer to lay a crop of oats or legumes first up to be ploughed in , get a soil analysis done ,fertilise to rectify deficiencies and away you go. Depending on water availability,income can be had during the process, firewood, green feed etc.

* for the uninitiated clydesdales are draught horses.(working them is how I learnt to swear)

<{POST_SNAPBACK}>

I lived for one snowy winter up in the hills on a homestead that used draught horses for some farming, getting firewood out of the hills, hauling water, getting cars pulled out of snow filled ditches, and to pull a sleigh to get people in and out of the 1 kilometer drive way when the snow was too deep for the trucks to pass. The driveway snaked through the woods and even though it was a hassle to have to unload the pickup and put everything into the sleigh and then unload up the hill it was alway fun and exciting too. Living with working draught horses is one of the coolest things in the world......

[ozzydom]

Good thinking--one should know the way out of a room before one enters it.

I do not like the ricepaddy idea -trending more towards vegetables /produce  growing . If worked by machinery the soil would have to be pretty clesr of stumps /roots etc,but if mainly/partly worked by hand that would not hamper the procees too much, But how serious is the problem with root extracts poisionig the surrounding area? Once the tree is dead ,is that still a problem?

<{POST_SNAPBACK}>

I have no direct experience with eucalyptus but I have alot of experience with organic gardening and have read extensively on the subject. If you want hard facts about dealing with eucalyptus removal I don't think you are going to find it here....and even if you did would you trust the source? If I were going to invest alot of time and money on this type of project I certainly would not base my decisions on what people here (myself included) say.....getting a link or other source of info is the best you can do here.

Having said that I'll give you my thoughts on eucalyptus roots. Since eucalyptus roots are organic they can be broken down by decay processes. I have never heard of some plant or animal produced material which did not break down naturally. The question is how long will it take. By using organic gardening/farming methods you will radically increase the rate at which this happens compared to the natural processes. The same thing can be said about the toxins that are in the leaves or that drip off of a tree in the sap.....all of these can be broken down with natural decay processes which can be done more rapidly with organic gardening/farming techniques.

Learning about organic gardening/farming techniques will take time and practice....the same thing is true of learning non-organic gardening/farming techniques. Many times people who have little/no experience in gardening/farming are interested in doing some project of this type and they go out and look for information that will assure them success in this endeavor. This is like trying to learn how to oil paint and thinking that the first thing you will do is a masterpiece. Farming is not a simple thing....it is an art and a science....best to learn to walk before you try running.

<{POST_SNAPBACK}>

There is no big deal in reclaiming ex eucalypt country,most of the farmland in oz was once just that,only these days we use dozers instead of *clydesdales.*

If its standing forest you just push every thing over with a dozer then you rip the roots up with a brush rake (like a big rake instead of a dozer blade) this takes the roots and leaves the soil, pile the debris in rows or heaps to dry ,where it can be salvaged as firewood (added income) or simply burnt in situ when dry.

Meanwhile you plough the land ready for sowing,some prefer to lay a crop of oats or legumes first up to be ploughed in , get a soil analysis done ,fertilise to rectify deficiencies and away you go. Depending on water availability,income can be had during the process, firewood, green feed etc.

* for the uninitiated clydesdales are draught horses.(working them is how I learnt to swear)

<{POST_SNAPBACK}>

I lived for one snowy winter up in the hills on a homestead that used draught horses for some farming, getting firewood out of the hills, hauling water, getting cars pulled out of snow filled ditches, and to pull a sleigh to get people in and out of the 1 kilometer drive way when the snow was too deep for the trucks to pass. The driveway snaked through the woods and even though it was a hassle to have to unload the pickup and put everything into the sleigh and then unload up the hill it was alway fun and exciting too. Living with working draught horses is one of the coolest things in the world......

<{POST_SNAPBACK}>

But did ya learn to swear chownah ??

[plachon]

This has been an interesting thread which as Bina says, has raised issues that were covered in an earlier thread on Farming in Isaan way back when (last year?).

In my opinion eucs are bad news anywhere in Isaan, IF they are planted as a monocrop plantation. Put simply, they seriously degrade the soil in every location I've seen. They not only exacerbate erosion and soil fertility decline, but they also impoverish local biodiversity. In short they are bad news for the environment and local livelihoods of villagers. This fact though has not stopped them being planted over wide swathes of land, often thanks to short sighted vision by Forestry Dept. and big buck inducements by agri-business companies, often linked to powerful political interests. After the second or third cut, yield drastically declines and the farmer is left with a forest of stumps with euc sprouts and increasing labour costs to get any future return. Yes, the land will gradually become valueless and desertified over time with monocrop eucs.

However, enough background on why they shouldn't be planted in the first place. The OP wanted to know how to rehabilitate the land after it had been screwed up by eucs. Deep ploughing or ripping may work in a dry climate like Oz, but I would have severe reservations about it leading to even worse erosion and nutrient / organic matter loss on the already exhausted soils under euc plantations, esp. where there was the slightest hint of a slope. As I write this, it is tipping down with rain outside and I can just picture all those ripped bare slopes losing all the top soil in gulley erosion. I see it all over the place at this time of year, both in cassava fields and increasingly, rubber plantations which are springing up all over the place in the Upper Northeast.

A better solution IMO than ripping would be selective digging out each stump with a Macro, filling in with a mix of good organic soil (and lime!) and replanting with a native tree variety (hardwood or fruit) when the rains come around May. Once the stumps were removed and there was something in its place, the young "forest" could be intercropped with something else, either cash crop, vegetable or soil improver legume. But don't expect good yields for several years and without a lot of TLC put back into the soil. Rehabilitation takes time and patience, something most Isaan farmers lack.

And for what its worth, I've come across soils in Isaan with pH values ranging between low 4s and up to 8 near the Mekong in Nakhon Phanom. They have v. low organic matter contents and crucially, low CECs. Lime can be a great soil amendment, but seems to be v. rarely used. It doesn't seem to be a matter of availability or cost, but just lack of knowledge of its benefits. Anybody got any first hand accounts of it boosting yields on their land profitably?

[plachon]

Is it true that eucalyptus wood fetches about 7000 baht a ton?

<{POST_SNAPBACK}>

One too many noughts Aletta. 700 - 800 baht / ton seems to be the going rate, with the higher rates going for use in the Neua Kaolee (Korean Barbeque) charcoal prodn. biz. The Phoenix pulp and paper mill in Nam Pong, Khon Kaen is still the main buyer in Isaan though I believe (and one of the main point sources of pollution in the river)

[chownah]

A better solution IMO than ripping would be selective digging out each stump with a Macro, filling in with  a mix of good organic soil (and lime!) and replanting with a native tree variety (hardwood or fruit) when the rains come around May. Once the stumps were removed and there was something in its place, the young "forest" could be intercropped with something else, either cash crop, vegetable or soil improver legume. But don't expect good yields for several years and without a lot of TLC put back into the soil. Rehabilitation takes time and patience, something most Isaan farmers lack.

And for what its worth, I've come across soils in Isaan with pH values ranging between low 4s and up to 8 near the Mekong in Nakhon Phanom.  They have v. low organic matter contents and crucially, low CECs. Lime can be a great soil amendment, but seems to be v. rarely used. It doesn't seem to be a matter of availability or cost, but just lack of knowledge of its benefits. Anybody got any first hand accounts of it boosting yields on their land profitably?

<{POST_SNAPBACK}>

I'm interested in the use of lime in Thailand too. It seems to me that way way back in my memory someplace I remember reading that on some soil types using lime is counterproductive...but I've looked around abit on the net and found nothing to indicate this. If you here of anything let me know.

What is CEC?

As for farmers lacking patience.....I'm sure you weren't meaning to say that all farmers lack patience (just saying this to extinguish the possibilityof a flame up here).....I think (my opinioin based on too few observations) that Isaan farmers come from a subsistence farming culture. In subsistence farming you don't have time or resources to spare...you can't afford a bad harvest as that would threaten your survival. This attitude leads to very conservative farming practices...alway doing what has been shown to provide continued survival. This attitude is one reason why many subsistence farmers throughout the world continue to use methods which do not provide optimum yields....because changing methods is seen as a threat to survival.

[plachon]

A better solution IMO than ripping would be selective digging out each stump with a Macro, filling in with  a mix of good organic soil (and lime!) and replanting with a native tree variety (hardwood or fruit) when the rains come around May. Once the stumps were removed and there was something in its place, the young "forest" could be intercropped with something else, either cash crop, vegetable or soil improver legume. But don't expect good yields for several years and without a lot of TLC put back into the soil. Rehabilitation takes time and patience, something most Isaan farmers lack.

And for what its worth, I've come across soils in Isaan with pH values ranging between low 4s and up to 8 near the Mekong in Nakhon Phanom.  They have v. low organic matter contents and crucially, low CECs. Lime can be a great soil amendment, but seems to be v. rarely used. It doesn't seem to be a matter of availability or cost, but just lack of knowledge of its benefits. Anybody got any first hand accounts of it boosting yields on their land profitably?

<{POST_SNAPBACK}>

I'm interested in the use of lime in Thailand too. It seems to me that way way back in my memory someplace I remember reading that on some soil types using lime is counterproductive...but I've looked around abit on the net and found nothing to indicate this. If you here of anything let me know.

What is CEC?

As for farmers lacking patience.....I'm sure you weren't meaning to say that all farmers lack patience (just saying this to extinguish the possibilityof a flame up here).....I think (my opinioin based on too few observations) that Isaan farmers come from a subsistence farming culture. In subsistence farming you don't have time or resources to spare...you can't afford a bad harvest as that would threaten your survival. This attitude leads to very conservative farming practices...alway doing what has been shown to provide continued survival. This attitude is one reason why many subsistence farmers throughout the world continue to use methods which do not provide optimum yields....because changing methods is seen as a threat to survival.

<{POST_SNAPBACK}>

It would be counterproductive using lime on soils that were already alkaline and had a good buffer capacity. But for the majority of Isaan and northern Thai soils which are naturally acidic (usually highly so), the lime additions can only be beneficial as far as I can see, and it is just a matter or whether the extra production justifies the costs (or vice versa). Highly acid soils (<pH5) would need large additions and the amounts would decrease as the the soil nears neutrality. The relationship is not straight line linear, as pH scale is logarithmic i.e. a pH of 5 is 10 times more acid than pH6.

CEC = Cation Exchange Capacity which is defined as the degree to which a soil can adsorb and exchange cations (i.e. positively charged ions). CEC is highly dependent on soil texture and organic matter content. Generally speaking, the more clay and organic matter in the soil, the higher the CEC. Soils with high pH (ie. alkaline) will also generally have higher CECs than acidic sandy soils.

Two factors determine the relative proportions of the different cations adsorbed by clays. First, cations are not held equally tight by the soil colloids. When the cations are present in equivalent amounts, the order of strength of adsorption is Al3+ > Ca2+ > Mg2+ > K+ = NH4+ > Na+.

Second, the relative concentrations of the cations in soil solution helps determine the degree of adsorption. Very acid soils will have high concentrations of H+ and Al3+. In neutral to moderately alkaline soils, Ca2+ and Mg2+ dominate. Poorly drained arid soils may adsorb Na in very high quantities.

In other words, the relationship between pH, CEC and soil organic matter is crucial to determining what your crops are able to uptake through their roots, and hence overall productivity and yield. As Isaan soils are sandy, acidic and have low OM contents, without concurrently boosting OM and pH (through lime additions), pouring on chemical fertilizer to crops, can be largely a waste of time and money, as the roots are not able to absorb the critical plant nutrients.

This is a very brief layman's description, but for more scientific details, go to sites like:

soils.tfrec.wsu.edu/ webnutritiongood/soilprops/04CEC.htm

By the way, I qualified my statement about farmers lacking patience with the word "most" before it, and would still stand by this assessment. They mostly do lack patience and the desire to see long term projects through (like gradual soil improvment over several seasons), because they tend to think (like most farmers throughout the so-called "developed world" in terms of short term gains). Agriculture in Thailand is going the way of the West, where it is no longer primarily an occupation to put food on tables, but to produce commodities for the commodity market. Hence, the average Isaan farmer will spend far more time on his/her cassava or sugar cane crop (international commodities), than they will on growing some safe, organic vegetables for their own family to eat. The land around them is gradually deteriorating and dying (quite literally in many places) and yet they still insist on practicing the same destructive methods of farming. And even more ironically, they are still mostly in debt and getting more indebted by the year. So actually, their farming methods inherently do jeopardize their own survival both economically and healthwise. At the same time , I recognize that is a treadmill that is very hard to get off (and usually they are forced off by the new land barrons of Isaan - sometimes farangs and their wives!) and the consumer is as much to blame as the producer.

Anyway, this has gone way off topic to the subject of land rehabilitation from euc plantations, yet is still strangely on-topic if you read between the lines.

[chownah]

.............It would be counterproductive using lime on soils that were already alkaline and had a good buffer capacity. But for the majority of Isaan and northern Thai soils which are naturally acidic (usually highly so), the lime additions can only be beneficial as far as I can see, and it is just a matter or whether the extra production justifies the costs (or vice versa). Highly acid soils (<pH5) would need large additions and the amounts would decrease as the the soil nears neutrality. The relationship is not straight line linear, as pH scale is logarithmic i.e. a pH of 5 is 10 times more acid than pH6. .................

..............This is a very brief layman's description, but for more scientific details, go to  sites like:

soils.tfrec.wsu.edu/ webnutritiongood/soilprops/04CEC.htm

<{POST_SNAPBACK}>

Plachon,

Thanks for the great input. It encouraged me to go look on the net one more time and I think I found what was lurking in my memory about problems associated with liming tropical soils. I found this link:

http://www.echotech.org/network/modules.ph...article&sid=557

Among other stuff it contains:

"Dangers of overliming

"In temperate region soils there tends to be little danger from adding too much lime, but this is not true of tropical soils. In fact, liming of most tropical soils is better viewed as calcium fertilization than pH adjustment, and the target pH should probably not exceed about 6.0, with optimum being more in the range of 5.0 to 5.5. In this pH range the aluminum and manganese concentrations in the soil solution are substantially decreased and these ions are no longer toxic to plants. Continued increase in pH, however, can cause molybdenum to become toxic. In addition, plants can become deficient in nutrients such as copper, zinc, boron, and manganese. This is both a result of these nutrients being less soluble at higher pH levels and decreased acid weathering of the few nutrient containing minerals still in the soil.

"Perhaps one of the most important problems of overliming tropical soils is physical, rather than chemical. As noted, soil permeability can be affected by liming. The structure in many tropical soils is stabilized by iron and aluminum oxides binding particles together and the structure has reached a high level of stability, accounting for the high infiltration rates and consequent rapid leaching of bases from these soils. Overliming can cause a destabilization of this structure and dispersal of soil particles, resulting in reduced permeability and lack of adequate drainage. Calcium and magnesium have a dispersing action that increases the number of small aggregates at the expense of larger ones. Presumably this is a case of sesquioxide (Fe and Al)-stabilized aggregates being dispersed by Ca2+. Since sesquioxide stabilized soils are typically found in the humid tropics, the reduced permeability, due to aggregate destabilization, can result is wet soils and complete change in the ecosystem. "

The local gov't farm advisor seemed to think that slightly acid soils were best (we were discussing rice) and said lime was not needed. Of course I'm stubborn and know that lime can be a cheap and effective yield booster...just as you are describing. I wish I could find someone with experience using lime in Thailand. Also I live in the north so our soils are different from Isaan.

[mpdkorat]

I'm no expert but a friend of mine said that the mucuna bean from South America did the trick in a very short period of time.

http://www.new-agri.co.uk/01-6/focuson/focuson8.html

[chownah]

I'm no expert but a friend of mine said that the mucuna bean from South America did the trick in a very short period of time.

http://www.new-agri.co.uk/01-6/focuson/focuson8.html

<{POST_SNAPBACK}>

Thanks for the link. If mucuna beans are not available in Thailand there are several other legumes available here both naturally and imported. I am becoming familiar with the legumes available here in the north but I think that since Isaan is considerably different than here they probably have their own collection of legumes to choose from. Has anyone seen or heard of mucuna beans in Thailand?

[bina]

geez plachon your soil analysis made my eyes cross...

As for farmers lacking patience.....I'm sure you weren't meaning to say that all farmers lack patience (just saying this to extinguish the possibilityof a flame up here).....I think (my opinioin based on too few observations) that Isaan farmers come from a subsistence farming culture. In subsistence farming you don't have time or resources to spare...you can't afford a bad harvest as that would threaten your survival. This attitude leads to very conservative farming practices...alway doing what has been shown to provide continued survival. This attitude is one reason why many subsistence farmers throughout the world continue to use methods which do not provide optimum yields....because changing methods is seen as a threat to survival.

good point and yes we had discussed that aspect: old timer farmers will keep doing things the same way and it is very hard to move them from this (i was recently offerred a job to teach work safety and hygiene to the farmers in our area... turned it down, try to teach goat dipping while wearing protective clothing to a 70 year old iraqi shepherd, yeah right!)... farmers are patient because crops and animals take time, but a specific cyclical time. to develop new improved crops, or animal stock, you need much more time and resources and dont see the results for a while: a good milking stock from a herd of goats means u only breed those that are 'premium' producers, then breed their daughters to studs that u marked as premium... this can take three to five years to see increase in milk production , if u dont buy 'premium' at a high initial cost from the very beginning .... for subsistence farmers, this means financial death... for a man with a plan and money to spare, three years is not wasted time but an investment for the future. the same with fields and crops....

http://www.thaivisa.com/forum/index.php?showtopic=8401&hl= the link to the infamous and long thread about farming,ecology and issaan

[Mobaan]

I did not realize what interest my topic on land reclamation would create --but that is good ,at least I know now that there are plenty people out there -in the neighborhood-I can brain drain ,once we get to the point.

Re . lime: Last year I tried (maybe not too hard ?) to buy lime . All I found was small 1 kg packs they wanted to sell at pharmacy prices . Where can I get large -bulk- quantities ,and what is lime called in Thai ( you know the product we would use as soil additive) ? What are the price ranges for this product?

[chownah]

I did not realize what interest my topic on land reclamation would create --but that is good ,at least I know now that there are plenty people out there -in the neighborhood-I can brain drain ,once we get to the point.

Re . lime: Last year I tried (maybe not too hard ?) to buy lime . All I found was small 1 kg packs they wanted to sell at pharmacy prices . Where can I get large -bulk- quantities ,and what is lime called in Thai ( you know the product we would use as soil additive) ? What are the price ranges for this product?

<{POST_SNAPBACK}>

Lime is called 'poon kow'. Literally this means 'white cement'. You should be able to buy it where the farmers buy their fretilizers. In the north you can buy fertilizer and lime all along the main road...it is stacked up and you just stop in at the house and buy it from them.....also there are stores all around for farm supplies. I've never bought any so don't know the price but I imagine it is really really cheap.

Do be aware that you can overdo lime on tropical soils.....as indicated in my post above....but I'm not sure if the soils in Isaan are considered tropical or not. I'd like to learn more about its use and I might have to just resort to trial and error since I haven't been able to find a local who has ever used it and ditto for TV. Let me know if you find anyone with experience with it....which will include you after you try it!!!