Peale in 1813, he wrote, “We now plough horizontally following the curvatures of the hills and hollow, on the dead level, however crooked the lines may be. Randolph’s farm is the only one which has not suffered his horizontal furrows arrested the water at every step till it was absorbed…Everybody in this neighborhood is adopting his method of ploughing, except tenants who have no interest in the preservation of the soil…” I have never seen the fields so much injured. Every hollow of every hill presented a torrent which swept everything before it. Three inches of water fell in the space of about an hour. Burwell in 1810, Thomas Jefferson wrote, “…we have had the most devastating rain which has ever fallen within my knowledge. This is an annual crop field with soil erosion above 20 tons per acre per year The field that was planted on the contour captured 6.7 inches of the rain compared to only 2.1 inches from the non-contoured field. In the 1938 Yearbook of Agriculture, “Soils and Men”, there is a table from an experiment where 11 inches of rain fell. Like the table saw in building a cabinet contour farming is one of the most important tools in building soil health. A farmer planting annual crops on sloping land needs a lot of tools as well: no-till planter, cover crops, crop rotation, and…contour farming. It was much faster to just plant in the most expeditious manner whether it be up and down the hill or around and around the field, this at the expense of capturing more water which is a priceless asset for crops in July and August.įarming is like making a fine cabinet it takes a lot of tools: a table saw, planer, miter box, band saw, drill press etc. With the coming of “no-till” farming, I witnessed farmers taking out their contoured, curving bands of crops and abandoning the practice of planting on the contour. No-till corn planted into a rye cover crop that was killed with herbicide I lamented as the strip cropping systems I laid out in Stuarts Draft were destroyed, replaced by a no-till, monoculture system. Farm Bill allows farmers to continue receiving USDA benefits as long as their soil erosion rates do not exceed 2 X “T”.īottom line: the new farmer has twice the soil erosion that agronomists know is sustainable and still receives USDA benefits. I informed him that he would not be building soil and eventually his soil resources would be exhausted. His cropping system yielded an average soil erosion rate of 4 tons per acre per year. The new farmer destroyed years of soil building conservation He said he would use no-till and didn’t need to plant on the contour. He wanted to plant the whole farm in one crop. The new farmer did not want the contour strips because it took more time plant. Many years later this farmer sold his land and a new farmer bought it. The farmer believed in building soil health he wanted zero erosion. The picture above shows some of his contour, strip cropping systems. He installed a system using contour farming and alternating bands of crops and perennials. In the late 80’s and early 90’s, I was working with a farmer in Stuarts Draft that had a lot of Berks-Weikert soil and it took every soil conservation measure we had to get his annual average soil erosion rate down to “T” or below. We can calculate the annual average soil erosion rate by using a formula agronomists call the Revised Universal Soil Loss Equation. Above the “T” value means we are losing more soil than we are making which is not sustainable. If the cropping system is below the “T” value for the soil then we are building soil health. The science of soil conservation is to develop a cropping system below this value. When I was working in Augusta County, Virginia some of our soils were very erosive, one soil, Berks-Weikert had a very low tolerance for soil erosion at two tons per acre per year. I laid out many contour strip cropping systems in my career with the Natural Resources Conservation Service, formerly the Soil Conservation Service. The simple act of planting across the slope instead of up and down the hill does two very important things: it captures at least twice the rainwater and reduces soil erosion up to eight-fold. This contour strip cropping system in Stuarts Draft Virginia incorporates many BMPs: contour farming, crop rotation, no-till planting, crop residue use, cover crops and perennial crops in rotation Contour farming captures twice the soil moisture and reduces soil erosion up to eight-fold
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