Farming A Slope

[teletiger]

2 weeks ago, my immediate neighbour got a crew of labour in to harvest 10 (or so) rai of sugar cane. As it transpired, this was the seed crop to lay down 70/80 rai of more sugar. This seed crop was in a sloped field L/R and cane was planted with the slope.

Last week, I noticed a group of children at the bottom of the slope......cutting the sugar??....500 metres....eyes 'ain't what they used to be. Wife confirmed "that's the labour cutting the cane".

Drove down there. Cane at the bottom of the field was 4 metres high. Top of the field, the usual 2+ metres.

Would cropping against the slope have resulted in a uniform 3 metre crop? I.e no overall gain? The holy grail of course would be to get a uniform 4 metre crop. A 25% gain. Something to ponder....my land has 5 different slopes.

My main concern with slopes is soil erosion. A big problem locally. (hilly area)

Some sites with info:

http://www.peisland.com/agrtour/xslope.html

http://answers.yahoo.com/question/index?qi...08013113AAzTapl

http://www.ctahr.hawaii.edu/wq/publication...mingCrop330.pdf

http://tucson.ars.ag.gov/isco/isco15/pdf/B...%20gradient.pdf (technical)

http://www.omaf.gov.on.ca/english/environm.../nontillage.htm

One for Jgeek. http://www.imde.ac.cn/journal/Vol_01/10.pdf

The contrarian in me is showing.

http://users.tpg.com.au/icanadsl/newslette...0V6%20final.pdf

Quote:

research conducted by local Queensland DPI&F and DNRW

staff showed that DTS (down the slope) farming resulted in slightly more run-

off and erosion.

“But that was during a fairly low rainfall period, when levels

of run-off and erosion in both systems were pretty small.

“When we got big falls of rain in early 2008, that trend

was reversed, and ATS (against the slope) resulted in more damage and soil

erosion,” Mr Spackman said.

Most sites I looked at gave a 50% saving in soil erosion ATS.

Regards.

[farmerjo]

I think it would have been done this way for irrigation purposes.

I have undulating land and the local sugar rep advised its alright to plant down the slope but no more than 180 meters long otherwise erosion will cause problems eg washing fertilizer away.(to bottom of row)

Depending on the fall of land of course,you may need to construct some contours.

The only problem with 180 meter rows is if you plan to use soilmate liquid fertilizer then there equipment is only good for 100 meter rows.

[IMA_FARANG]

2 weeks ago, my immediate neighbour got a crew of labour in to harvest 10 (or so) rai of sugar cane. As it transpired, this was the seed crop to lay down 70/80 rai of more sugar. This seed crop was in a sloped field L/R and cane was planted with the slope.

Last week, I noticed a group of children at the bottom of the slope......cutting the sugar??....500 metres....eyes 'ain't what they used to be. Wife confirmed "that's the labour cutting the cane".

Drove down there. Cane at the bottom of the field was 4 metres high. Top of the field, the usual 2+ metres.

Would cropping against the slope have resulted in a uniform 3 metre crop? I.e no overall gain? The holy grail of course would be to get a uniform 4 metre crop. A 25% gain. Something to ponder....my land has 5 different slopes.

My main concern with slopes is soil erosion. A big problem locally. (hilly area)

Some sites with info:

http://www.peisland.com/agrtour/xslope.html

http://answers.yahoo.com/question/index?qi...08013113AAzTapl

http://www.ctahr.hawaii.edu/wq/publication...mingCrop330.pdf

http://tucson.ars.ag.gov/isco/isco15/pdf/B...%20gradient.pdf (technical)

http://www.omaf.gov.on.ca/english/environm.../nontillage.htm

One for Jgeek. http://www.imde.ac.cn/journal/Vol_01/10.pdf

The contrarian in me is showing.

http://users.tpg.com.au/icanadsl/newslette...0V6%20final.pdf

Quote:

research conducted by local Queensland DPI&F and DNRW

staff showed that DTS (down the slope) farming resulted in slightly more run-

off and erosion.

“But that was during a fairly low rainfall period, when levels

of run-off and erosion in both systems were pretty small.

“When we got big falls of rain in early 2008, that trend

was reversed, and ATS (against the slope) resulted in more damage and soil

erosion,” Mr Spackman said.

Most sites I looked at gave a 50% saving in soil erosion ATS.

Regards.

From my limited experience I think contour plowing taking the contour of the land would be better for the long term erosion of the land. It seems that water running slowly down the slope would be a better thing than have it just running straight down the slope. But then I'm not an expert.

Edited April 3, 2009 by IMA_FARANG

[Lickey]

This time last year we were planting cassava, and they were planted across the slope, Sis in law planted cassava too, between her rubber trees, she had no choice except to plant downhill, after a few heavy rains, the water had found a way through our cassava, i then dammed the water so it would go all over the banana plantation, we lost about 15 plants, SIL lost 3 200mtr rows to water flow, [pics on the cassava pinned topic] ..

I thought about damming the water before it entered the cassava, but this would lead to more channels of water washing out plants, so now i let the water run where it wants,with the odd banana culm dam, so for me, always across a slope!

Lickey,,

[slapout]

Contour farming has been one of the accepted methods and has proven time and again to reduce erosion. It could have been the soil at the bottom of field was better due to past erosion of good top soil further up the hill. As mentioned previously, flow of water can be hindered by contour planting, making flood irrigation a real pain. If its a dry climate and moisture comes via controlled irrigation, planting downhill can work with little erosion. On the other hand if you have adequate rainfall for a crop why would you not plant following contour of land?

[Maizefarmer]

IMA FARANG's comments above are bang on the mark

The base of the slope retains the most moisture - simple as that.

Nope - plant which ever way you will, the lower down the slope the crop goes the higher yield tends to be. Its the same with maize and cassava on gradients above a certain percentage.

On really steep gradients planting diagonaly is the only way to go - tractor stability can be a big issue on soft soils along the gradient of steep slopes (drivers are killed every year in Thailand ploughing with steep gradients - hardly ever see Thai tractors with ROPS), and planting across gradients - well, you just need one hard downpour and all the top soil is washed off.

Edited April 4, 2009 by Maizefarmer

[Khonwan]

I prefer contour-farming. I find I have less soil erosion this way. Ruts should be repaired as they occur, or as soon as possible – I’ve stored a few tonnes of bagged sandy soil from my land (30kg) for this purpose.

Rgds

Khonwan