First Principles of Soil FertilityOrange Judd, 1908 - 265 páginas |
Dentro del libro
Resultados 1-5 de 27
Página 21
... exists in simple compounds called nitrates , which con- sist of nitric acid combined with one of the mineral elements of the soil . The majority of farm crops can use only that part of the nitrogen in the soil 21 Nitrogen as a Plant Food.
... exists in simple compounds called nitrates , which con- sist of nitric acid combined with one of the mineral elements of the soil . The majority of farm crops can use only that part of the nitrogen in the soil 21 Nitrogen as a Plant Food.
Página 22
... nitrates , so that so far as the nitrogen is concerned , the fertility of the land depends upon its nitrate content . The nitrate present in the soil at any one time is exceedingly small , but under proper con- ditions the supply may be ...
... nitrates , so that so far as the nitrogen is concerned , the fertility of the land depends upon its nitrate content . The nitrate present in the soil at any one time is exceedingly small , but under proper con- ditions the supply may be ...
Página 23
... nitrates . The transformation of organic nitrogen into nitrates undoubtedly results from the action of more than one species of bacteria , and takes place in three or more different steps . The organisms necessary to produce these ...
... nitrates . The transformation of organic nitrogen into nitrates undoubtedly results from the action of more than one species of bacteria , and takes place in three or more different steps . The organisms necessary to produce these ...
Página 24
... nitrates , and perhaps some other nitrogenous compounds , with the final result that the nitrogen is set free and returned to the air in its elemental condition . This process of course , robs the soil of a part of its nitrogen , and is ...
... nitrates , and perhaps some other nitrogenous compounds , with the final result that the nitrogen is set free and returned to the air in its elemental condition . This process of course , robs the soil of a part of its nitrogen , and is ...
Página 26
... of the bacteria that produce the nodules , and in the absence of these organisms the legumes are quite as dependent upon the supply of nitrates as are the other orders of plants . It may be further 26 FIRST PRINCIPLES OF SOIL FERTILITY.
... of the bacteria that produce the nodules , and in the absence of these organisms the legumes are quite as dependent upon the supply of nitrates as are the other orders of plants . It may be further 26 FIRST PRINCIPLES OF SOIL FERTILITY.
Otras ediciones - Ver todas
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.