First Principles of Soil FertilityOrange Judd, 1908 - 265 páginas |
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Página 26
... leached from a natural soil so as to introduce any bacteria that might exist natural- ly in the earth . He found that in the perfectly sterile soil there was no gain in nitrogen by any of the plants , but that in the pots to which the ...
... leached from a natural soil so as to introduce any bacteria that might exist natural- ly in the earth . He found that in the perfectly sterile soil there was no gain in nitrogen by any of the plants , but that in the pots to which the ...
Página 38
... leaching of the soil , or removal of plant food in the drainage water . For practical purposes nitrogen may be said to be the only element lost in this way . As the nitrogen removed by leaching is all in the form of nitrates , any loss ...
... leaching of the soil , or removal of plant food in the drainage water . For practical purposes nitrogen may be said to be the only element lost in this way . As the nitrogen removed by leaching is all in the form of nitrates , any loss ...
Página 39
... leaches . through this soil is analyzed , it is found that the potash It is a dangerous practice to allow soils to remain bare and exposed to washing rains . Thousands of acres of good lands have been destroyed in this country in the ...
... leaches . through this soil is analyzed , it is found that the potash It is a dangerous practice to allow soils to remain bare and exposed to washing rains . Thousands of acres of good lands have been destroyed in this country in the ...
Página 87
... leaching and more rational methods of tillage , have for the most part removed this necessity . There is no doubt of the efficiency of fallowing as a method of making plant food available , especially if the soil is frequently stirred ...
... leaching and more rational methods of tillage , have for the most part removed this necessity . There is no doubt of the efficiency of fallowing as a method of making plant food available , especially if the soil is frequently stirred ...
Página 88
... leached out of the ground if present in any considerable amount . One of the dangers of the practice of fallowing is that if the land is left bare during the heavy rains of fall and winter , a large part of the nitrates formed during ...
... leached out of the ground if present in any considerable amount . One of the dangers of the practice of fallowing is that if the land is left bare during the heavy rains of fall and winter , a large part of the nitrates formed during ...
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Términos y frases comunes
acid and potash acre agricultural ammonia amount of nitrogen amount of plant animals applied average bacteria barn barnyard manure bedding carbonic acid clay clover commercial fertilizers complete fertilizers composition compounds condition corn crop decay deep stall denitrification drainage dry matter elements of plant Experiment Station fact farm farmer feeding fertilizing constituents fertilizing materials fertilizing value field grain green manuring ground grown hot fermentation humus important inches increase ingredients kainite land leaching legumes leguminous lime liquid excrement loss of nitrogen lysimeters manure produced materials ments method mineral matter mixed moisture necessary nitrate of soda nitrification nitrifying bacteria nitro nitrogen nure obtained organic matter oxygen phoric acid phos phosphate phosphoric acid plant food plant growth plots plowed pounds practically present rains ration removed rock roots rotation shown soil soil contains soluble substances sufficient sulphate superphosphate supply surface tillage tion urine wheat yield
Pasajes populares
Página 225 - Furthermore, the mineral elements are relatively cheap, while the nitrogen is relatively expensive, and the economical use of this expensive element, nitrogen, is dependent to a large degree upon the abundance of the mineral elements in the soil. It is, therefore, advocated that for all crops and for all soils that are in a good state of cultivation, a reasonable excess of phosphoric acid and potash...
Página 1 - ... woods ; All silent is the earth and sky, Except with his own lonely moods The blackbird holds a colloquy. Over the broad hill creeps a beam, Like hope that gilds a good man's brow, And now ascends the nostril-stream Of stalwart horses come to plough.
Página 245 - One will seek to know what the different forms of plant-food are, what they do, from what sources they can be obtained, and how he can use them to best advantage. He will become to some extent an investigator, and will, of necessity, take a deeper interest in his work.