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Show Soil Building The difference between soil building build-ing and soil mining is shown in the chart below. Soil building means increasing the soil's organic matter and plant food supply and maintaining maintain-ing high crop yields. It means feeding feed-ing the soil and letting the soil feed the crops, rather than trying to feed each individual crop. The comparative results shown here were obtained at the Ewing soil experiment field in Illinois. One plot has had no soil treatment since the field was established in 1910. The other plot has had large amounts of 60IL TREATED WITH MANURE. LIME Er - 1 PH06PHATE SOIL TREATED CCW A OATS ALFALFA WHEAT a jfVV ' Ifei-- l6 TONSOF L j'lS T f ORGANIC MATTER 0r SOIL TONsV IPER ACBE ' tog f ( O-M. 1 lime, phosphate and potash to get heavy stands of deep-rooted legumes. leg-umes. Corn stalks have been returned re-turned to this plot. The rotation on both plots has been corn, oats, clover clo-ver and wheat. Crop yields covering a four-year rotation tell the story. Corn production pro-duction on the fertilized plot was four times greater than on the untreated un-treated field; oats nearly four times and wheat about eight times greater. great-er. Clover yield on the fertilized plot was 1.9 tons per acre; the untreated un-treated plot is too acid to grow legumes. Despite the greater amounts of nitrogen and organic matter used In producing the higher yields, the fertilized fer-tilized plot still" contains 4 tons more organic matter and 460 pounds more nitrogen than the untreated field. |