16 MAN ON THE LANDSCAPE 



in order to judge the degree of chlorophyll activity on one less luxuri- 

 ant. Such judgment, it must be noted, is of questionable value in 

 determining the nutrient quality of the landscape. 



Power Output of Growing Plants. Plants not only store energy 

 useful to lower animals, to man, and to man's mechanical engines, 

 but plants themselves use a part of the incoming sun power to op- 

 erate themselves. Plants share with animals certain functions. They 

 grow and reproduce. These activities require energy, and the active 

 cells draw on the stored manufactured fuel as needed. This is a point 

 on which the layman is often confused. He mistakenly supposes that 

 plants and animals are purely opposite in function, that plants make 

 fuel, use carbon dioxide and release oxygen; while animals use fuel 

 and oxygen and release carbon dioxide. 



It should be emphasized that most plant cells function much as 

 do animal cells, that plants play a dual role, both storing energy and 

 using it. Fortunately, like bees, they store far more than they use. 



Albrecht 4 states that a 40 acre field of corn at peak activity con- 

 sumes as much fuel as a 40 horsepower engine. This represents the 

 power output of all the plant and animal cells which contribute to 

 the growth of the crop. It includes the growing and multiplying cells 

 of the bacteria, the fungi and the animal population in the soil, in- 

 cluding protozoa, earthworms, insects and others. The figure is secured 

 by measuring the carbon dioxide released from the soil a sort of 

 metabolism test of the earth working at high speed with the sun power 

 at full throttle, and supported by release from the soil of accumulated 

 energy of the past. 



The Building Blocks of Life. In speaking of carbohydrates and 

 fats, we are dealing with materials compounded almost wholly from 

 atmosphere and moisture. They are quite flimsy in a sense and change 

 back into energy forms with little difficulty. Let us consider proteins. 

 By adding nitrogen and certain other elements to sugar, plants can 

 produce a protein. The catch is that plants cannot use gaseous nitro- 

 gen as found in the air. It must be in a different form, as nitrate 

 something you can get your hands on, something found in soil. 



Nitrogen, plus sulphur, and a wide range of other minerals, enable 

 the plant to make proteins, the materials of which living cell parts are 

 constructed. These cells make up the plant itself. Obviously, unless 

 the plant can come into existence, it cannot store energy. The remark- 

 able fact is that plants construct their own building blocks, proteins, 

 out of not less than 23 sub-materials, 23 amino acids. These amino 

 acids are compounded in various proportions from air, water, and a 

 minimum of 10 soil minerals. This construction job has been called 

 biosynthesis, and no specific machinery in the plant for doing it has 

 been discovered. 



The amount and number of proteins in a plant depends then on 

 soil fertility. Lime (calcuim) is especially important because of its 



4 Albrecht, Wm. A., Why Do Farmers Plow, American Potash Institute, Inc., 

 Washington, D. C., (no date), p. 2. 



