SMITH ON NEW PROBLEMS AND NEW PHASES OF OLD ONES. 143 



NEW PROBLEMS AND NEW PHASES OF OLD ONES. 



BY CLINTON D. SMITH, AGRICULTURAL COLLEGE. 



I shall attempt, briefly, to state something about some of the problems 

 that confront the thinker and worker along lines of agricultural pro- 

 gress without stopping to discuss »any one of them at all thoroughly. 



Whoever is interested in the literature relating to soils has noted the 

 trend away from chemistry and towards physics in the recent discussions 

 relating to the proper treatment and fertilization of fields. Formerly 

 it was.supposed that the chemical constitution of the soil was a sufficient 

 guide as to what the soil would do and what it needed to make it grow 

 any one of our common cereals. The opposition of practical experience 

 to this theory was attributed to the ignorance of the objector. Now 

 we are studying the physical side of the questions much more, perhaps, 

 than the chemical. Water is the greater desideratum in plant growth. 

 How can we hold the rain falling in the spring for the use of crops grow- 

 ing in the late summer is the great problem presented to the practical 

 farmer and not how to retain the nitrogen, phosphoric acid and potash, 

 important as that question is. Hence comes the importance attached 

 to humus and the stress laid upon the application of barn yard manure 

 or plowing under green crops as a means of maintaining fertility. Form- 

 erly the value of manure was estimated entirely by the amount of nitro- 

 gen and other plant elements it contained, now it is valued because it 

 contributes decaying vegetable matter to the soil and thus helps 

 the physical, water holding, capacity of the soil. 



Cultivation is likewise carried on with this idea of conservation of 

 moisture clearly in mind. The fact that, through the bulletins of ex- 

 periment stations, and later through the current agricultural press, the 

 knowledge of the correct principles in this matter has been widely 

 disseminated, makes possible the successful culture of certain new crops 

 in this State that would not be here at all without this improvement 

 in method. 



The careful work of the scientist in the studv of fungus and insect 

 enemies of fruits, cereals and vegetables is yielding an abundant harvest 

 of good to the State at large. No sooner does a new disease attack any 

 valuable plant than the scientist interested in the department involved 

 is working out a life history and suggesting proper remedies. Thanks 

 to the cryptogamic botanist we know how to ward off most of the 

 diseases that afflict our fruit trees, but we have yet other work for him 

 to do. Who shall diagnose the cause of peach yellows, little peach, crown 

 gall, or rosette? The work in this line is just begun and new problems 

 are constantly confronting us. 



He who is interested in combating destructive insects may find his 

 best ingenuity put to the test to suggest a remedy for the threatening 

 gypsy moth, the introduction of which into Michigan would mean the 

 practical annihilation, not only of the fruit trees but of the forests 

 themselves. 



