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| Registros recuperados: 94 | |
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| Cary, J.W.; Kohl, R.A.; Westermann, D.T.; Rickman, R.W.. |
| One of the most effective ways to prevent the wind erosion of sandy soils is to maintain a continuous crop cover. Summer row cropping following a winter grain cover offers several attractive features, although it does present management problems. The grain cover must be established in the fall after harvesting the row crop, and the transition back to a row crop in the spring must be made without leaving the soil surface unprotected from the wind. This report summarizes 4 years of observations and exploratory studies in which a variety of cover-row cropping management systems were tested with emphasis on methods for establishing row crops directly in the winter cover. Pertinent literature and observations of other field trials are also discussed. |
| Tipo: Technical Bulletin |
Palavras-chave: Sprinkler irrigation; Erosion; Mass Import - autoclassified (may be erroneous). |
| Ano: 1975 |
URL: http://eprints.nwisrl.ars.usda.gov/1129/1/302.pdf |
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| Westermann, D.T.. |
| Plant analysis historic beginnings are generally attributed to T. de Saussure (1804) following studies by van Helmont, Joseph Priestly, Henry Cavenish, and Antonine Lavoisier. de Saussure showed that the composition of plant ash varied with the part analyzed, with the age of the plant, and with the soil upon which the plant grew. The ash was chiefly composed of alkalis and phosphates. Erasmus Darwin in his 1800 book, Phytogia: The Philosophy of Agriculture and Gardening (London, J. Johnson) wrote that both nitrogen (N) and phosphorus (P) were essential components of plants. In 1833, the Fifth Duke of Richmond showed that the value of bone meal fertilizing was due to its P component rather than calcium (Ca), although Justus von Liebig (1852) is... |
| Tipo: Book Section |
Palavras-chave: Research methodology; Mass Import - autoclassified (may be erroneous). |
| Ano: 2005 |
URL: http://eprints.nwisrl.ars.usda.gov/738/1/1170.pdf |
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| Registros recuperados: 94 | |
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