First Principles of Soil FertilityOrange Judd, 1908 - 265 páginas |
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Página 13
... inches deep . This again takes no account of the quantity of water lost from the land by percolation or drainage . It has been estimated that this amount is at least equal to that used by vegetation , so that one acre of corn pro- bably ...
... inches deep . This again takes no account of the quantity of water lost from the land by percolation or drainage . It has been estimated that this amount is at least equal to that used by vegetation , so that one acre of corn pro- bably ...
Página 14
... Inches of Water Required Wheat Barley Oats Corn 2.52 3.36 m 15 4.5 3.24 2.35 20 6.0 4.28 3.14 30 9.0 6.42 5.7 40 12.0 8.56 50 15.0 10.70 7.84 5.04 6.72 8.40 60 18.0 12.84 9.40 10.08 6.27 Functions of Water . - Water is important to the ...
... Inches of Water Required Wheat Barley Oats Corn 2.52 3.36 m 15 4.5 3.24 2.35 20 6.0 4.28 3.14 30 9.0 6.42 5.7 40 12.0 8.56 50 15.0 10.70 7.84 5.04 6.72 8.40 60 18.0 12.84 9.40 10.08 6.27 Functions of Water . - Water is important to the ...
Página 64
... inches on the side , presents a sur- face of 24 square inches . If this cube is cut once in each direction 8 cubes are formed , each one inch on a side , giving a total of 48 square inches of surface , so that cutting only once in each ...
... inches on the side , presents a sur- face of 24 square inches . If this cube is cut once in each direction 8 cubes are formed , each one inch on a side , giving a total of 48 square inches of surface , so that cutting only once in each ...
Página 68
... inch , and their aggre- gate surface will be 31.416 square inches . If , however , the diameters of these spheres be reduced to one- hundredth of an inch 1,000,000 of them will be required to make a cubic inch and their total surface ...
... inch , and their aggre- gate surface will be 31.416 square inches . If , however , the diameters of these spheres be reduced to one- hundredth of an inch 1,000,000 of them will be required to make a cubic inch and their total surface ...
Página 70
... inches deep of very dry soil , so dry and loose that it can not take up the water from the layer next beneath it . The same end can be attained by covering the ground with loose straw or other similar material , the principle underlying ...
... inches deep of very dry soil , so dry and loose that it can not take up the water from the layer next beneath it . The same end can be attained by covering the ground with loose straw or other similar material , the principle underlying ...
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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 187 - The production possible from a definite amount of plant -food can be secured only when the conditions are such as to permit its proper solution, distribution and retention by the soil. The fact that fertilizers may now be easily secured, and the ease of application, have encouraged a careless use, rather than a thoughtful expenditure, of an equivalent amount of money or energy in the proper preparation of the soil.
Página 221 - Furthermore, the mineral elements are relatively cheap, while the nitrogen is relatively expensive, and thus that 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 241 - 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.
Página 225 - When such crops as corn, cabbage, grass, potatoes, etc., have a luxuriant, healthful growth, an abundance of potash in the soil is indicated ; also, when fleshy fruits of fine flavor and texture can be successfully grown. (e). When a soil produces good, early maturing crops of grain, with plump and heavy kernels, phosphoric acid will not generally be found deficient in the soil. Such general indications may often be most helpful, and crops should be studied carefully with these facts in mind.