Bulletin Volume 28-32 (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1913 Excerpt: ... growth of clover, owing to unfavorable weather conditions in winter and early spring. The following table gives the average results of mechanical analyses of samples of the soil and subsoil of this type: Methods Of Improvement For Marshall And Dodgeville Silt Loams. The areas of these soils, while differing somewhat in topography, are quite similar in chemical composition. Their analysis indicates between 1,300 and 1,400 pounds of phosphorus, 35,000 pounds of potassium, and 5,000 pounds of nitrogen in the surface 8 inches per acre. Their relatively large amount of nitrogen is due to the larger accumulation of organic matter which has taken place in these soils, due to their being in prairie rather than timber condition. It is probable that this organic matter has also tended to increase the phosphorus above that found in the Knox silt loam type. When first broken these soils showed a very high degree of fertility, and do still, except where poor systems of farming have caused the reduction of the active organic matter in the soil. In such cases even though the soil remains quite dark and has a good total supply of organic matter, this is in a resistant form in which it has been left by the oxidation of the more active vegetable matter. The improvement of these lands demands an increase of active organic matter through the use of green manuring crops, particularly legumes, or large quantities of manure, as in the case of Knox silt loam. Owing to the fact that these soils, for the most part, occupy the higher areas of the ridge section of the county, they are less likely to receive lime in water percolating down from higher lands than in the ease of the Knox soils; and for this reason, as well as on account of their larger amount of organic matter, show more...