New York Agricultural Experiment Station. 53 



the plant, just as the blood in the animal body carries to ev^erj por- 

 tion the nntrinient adapted to each organ and part. 



Nitrogen. — The influence of nitrogen in its various forms upon 

 plant growth is shown by at least three striking effects. 



First. The growth of stems and leaves is greatly promoted, while 

 that of buds and iiowers is retarded. Ordinarily, most plants, at a 

 certain period of growth, cease to produce new branches and foliage, 

 or to increase those already formed, and commence to produce 

 flowers and fruits, whereby the species may be perpetuated. If a 

 plant is provided with as much available nitrogen as it can use just 

 at the time it begins to tlower, the formation of flowers may be 

 checked while the activity of growth is transferred back to and 

 renewed in stems and leaves, which take on a new vigor and 

 multiply with remarkable luxuriance. Should flowers be produced 

 under these circumstances, they are sterile and produce no seed. 



Second. The next effect of nitrogen upon plants is to deepen the 

 color of the foliage, which is a sign of increased vegetative activity 

 and health. 



Third. Another effect of nitrogen is to increase in a very marked 

 degree the relative proportion of nitrogen in the plant. 



Phosphorus. — Experiments have shown that plants will die 

 before reaching maturity, unless they have phosphoric acid com- 

 pounds to feed upon. Phosphates appear to perform three distinct 

 functions in plants. 



Fi)'d. They aid in the nutrition of the plant by furnishing the 

 needed quantities of phospliorus. 



Second. They aid the plant, in some way not well understood, 

 to make use of or assimilate other ingredients. Phosphorus is 

 found in the seeds of plants, and, as already stated, a plant does 

 not come to maturity and so does not produce seeds, unless phos- 

 phates are present in the soil for the plants to feed upon. The 

 liberal application of available phosphate compounds appears to 

 hasten the maturity of plants. 



Third. Certain forms of phosphates render the albuminoids 

 sufliciently soluble to enable them to be carried from the growing 

 parts of plants to the seeds, in which they accumulate in quantity. 



Sulphur is required by plants in order to produce the albuminoids 

 and many of the vegetable oils, such as those contained in horse- 

 radish, mustard, turnips, onions, etc. Otherwise, it is not clearly 

 known what functions sulphur may perform in plant development. 



