I was struggling to understand the keyline concept, was getting stuck, and it happened every time I tried to understand, a big thanks to you, did understand well, very nice for even for a layman Sampath
Great demonstration, but aren't the keyline trenches supposed to be level? I am digging keyline trenches from a valley and it has been effective in pulling the water to the ridges.
Why does each keyline in a valley not slope downward towards each ridge? In other words, if you stand on the ridge of an A-frame roof and pour water on it, the water naturally flows down.
Thanks for that explanation. It seems keyline spreads water. Whereas swales hold water back to fill the subsoil, and watertables. Im going to have a go at swales as it seems to suit my land. We have been informed a La Nina has formed and we should get some much needed rain. Not much rain in the past 5 years, especially the past two years. Even trees are dying.
Why am I wrong in thinking that the off-contour lines should be skewed downward.in parallel? Wouldn't that make it easier for the water to naturally flow to the top of the ridge below? In other words, if the off-contour lines are horizontally parallel, it would seem, as in the demonstration, that the water would not always flow to the ridge. However, wouldn't gravity do more work for us if as the water flowed down and then to the right or left, the off-contour line was skewed downward, naturally forcing the water to continue a downward path to the ridge below?
The only thing I'm stuck on is why are the parallel lines above a contour necessarily going toward the ridge. Isn't it possible that they could be sloped slightly toward the valley rather than the ridge if we simply make parallel lines above a contour line?
Not sure if I understood completely what you said, but here it goes my attempt. ;-) If it leans toward the valley. The water will not spread in the direction of the outer ridge. In fact it would be a worse situation because more water would be directed to the valley, when the intention is precisely the opposite. Take it away from the valley. If parallel to the contour line, it will not be so effective. Because it will not favor a wider spread over the land. Remember the "key line" is a relatively shallow cut in the soil. It cannot contain a large amount of water. Although it can effectively distribute the water if a downstream condition is given. Cheers
downbntout - No. That´s a misunderstanding. In a topo map lines are on contour, or saying in another way at the same height. On the keyline system the lines lean from the valley to the ridge. Higher in the valley, lower in the ridge. Hope it help. Cheers
This is not a good explanation of Keyline pattern cultivation. The key Line by definition is an extension of the key point of the valley. The key point is that place where the topography changes from convex to concave. This is the place in the landscape where water will begin to slow in a landscape. One does not subsoil parallel to the Keyline. One crosses the keyline, higher in elevation from the valley to lower in elevation to the ridge. Water for Every Farm clearly shows keyline cultivation patterns as not being parallel to contour lines. The wrong application of subsoiling can actually dry up landscapes. Darren Doherty or Owen Hablutzel are to people to be paying attention to.
