226 HOW CROPS GROW. 



On dividing the above quantities by the number of days 

 of the respective periods, there results: 



The Average Daily Gain or Loss per Acre during 

 each Period. 



Table TV.—Bretschneider. 



4. — Table III, and especially ^Table IV, show that the, 

 gain of organic matter in Bretschneider's oat-crop went 

 on most rapidly at or before the time of blossom (accord- 

 ing to Arendt at the time of heading out). This was, then, 

 the period of most active growth. Afterward the rate of 

 growth diminished by more than one-half, and at a later 

 period increased again, though not to the maximum. 



Absolute Quantities of Carbon, Hydrogen, Oxy- 

 gen, Nitrogen (Organic Matter), and Ash in the dry 

 oat-crop at the conclusion of the several periods {lbs. 

 per acre) : 



Table Y.—Sretschneider. 



Carbon. Hydrogen. Oxygen. Nitrogen. Ash.* 



1st Period, 593 80 465 46 110 



2d&3d" 2,137 286 1,575 122 263. 



4th " 2,600 343 2,043 150 291 



6th " 3,229 405 2,713 1C7 372 



Amounts of Carbon, Hydrogen, Oxygen, Nitro- 

 gen, and Ash-ingredients assimilated by the oat-crop 

 during the several periods. Water of vegetation is not 

 included {lbs. per acre) : 



TABLE Yl.—Bretschneider. 



Carbon. Hydrogen. Oxygen. Nitrogen, Ash-ingredients. 



*In Bretsohneidpr'a analyses, "ash" signifies tlie residue left after 

 carefully burning the plant. In Axendt.s investigation the sulphur 

 and chlorine were determined in the unbumed plant. 



