For the Palouse, I view "Contour Buffers" in a similar light to landfills, a resource for the future, ---> if managed properly. From the beginning I have been a supporter of buffer strips as a practice to reduce soil erosion. Recently, I am having some second thoughts about that. I mostly see them being managed for short term economics (gov. land rental) without a vision to convert these lands back to a long term productive asset. Vertical drops at buffer strip transitions are not being addressed, and I have seen trees planted in areas that could be made into good crop production areas using D.S. methods.
DETAIL:
My concern is: a)- that land managers are not managing these buffers with the idea of bringing them back into production at a future date, and b)-the management practices being followed will result in further destruction of the hill side, and c)- even the bottom ground will be effected by being overburdened with deposits of poor soils. Those who are direct seeding are in good position to reclaim these hillsides with improved soil structure; however, most of those continuing to use a conventional cultivation system are moving those hillsides into the waste land category, and raising the potential for future problems on productive lands below them. This is demonstrated by pic #1. Grass lands of "old" have a history of shedding water. This water overloads the farmland lying below the grass and causes erosion on those lower slopes. Frequently, when conditions are right, areas of soil will shear, and slump down hill, leaving an ugly hole in the hill side and a spoil pile below. The steeper the slope, and the height of the vertical drop at the transition, the more likely this event will occur.
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| pic #1 |
Pic #1: Shown is one of the oldest, and most extreme cases of hill side destruction. Originally, this hill side was farmed as part of the whole, which included the hill top and draw bottom. The original buffer on the rim of the hill was established decades ago. The second buffer strip was established many years after the first, and the newest, lighter green buffer is more recent. Notice the vertical drops that define the lower edge of each of the top two buffer strips. The top one is more severe then the second one. This may be do to a longer farmed period, or steeper slope, or both. The third, the bottom buffer strip has no visible vertical drop where is transitions to the crop land. This is probably because it is low on the hill side, and the modern plows can throw soil up the hill.
When the original (top) buffer was established, using conventional tillage, the make-up soil that was provided to the slope from the hill top was cut off. A soil berm has been developed over the years on the edge of the hill top. Without the make up soil from the top, tillage has gouged out the soil under the buffer strip. This practice has removed the thin mantel of top soil, if it existed, and exposed more erosion prone sub soils. This farming practice continued until the productivity under the buffer strip declined to the point where the operator took out another section of the hill side. And then a third. An equilibrium has probably been established below the third buffer strip where the remainder of the hill side will remain in production for years to come; however, the likely hood of reclaiming the buffer strips, other than the third (lowest) one is nil. The hill side's productivity could only be re-established by dozing top soil from the draw bottom up onto it. This would be very expensive. Dozing the berm at the hilltop will probably not damage further the production, but dozing the vertical drop from above will definitely degrade the hillside. This pic is going to become a common sight across the Palouse instead of a rarity, if land managers don't become stewards of their land instead of miners of their land.
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| pic #2 |
Pic #2: Shown, is a vertical drop under a buffer strip caused by a short period (10 yrs) of conventional tillage through the action of the disc, cultivator, and rod weeder (8-10 inches). This slope is approximately 30%. This damage can be reversed using conventional tillage methods by employing the plow. With modern plows, and tractors, soil can be rolled up-hill on nearly any slope.
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| pic #3 |
Pic #3: Shown, is a transition between a buffer strip and crop ground that has existed for more then 20 years. The pic is deceptive. The slope is approximately 30%. There is virtually no vertical drop at the transition (0.5-1"). Attached to this buffer strip is another section that is much older, and was established while we were conventionally tilling, and not thinking about reclaiming the property. There are areas with vertical drops of 18" or less, and are short in length, that we will be able to reclaim when the time comes. Current plans are to leave this poor producing southerly exposed slope in CRP as long as there is a program. We probably should consider putting a low rate of fertilizer on these strips annually, to increase the grass production (residue) which will help build soil and it's structure over time. When there is no longer programs that will provide some source of income from this property, we will have the option of returning it to crop production. It will never have the productive capacity that it had 100 years ago, but we will be able to call it a productive asset instead of waste ground.
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