178 DEPARTMENTAL REPOETS. 



cially upon their relation to moisture. In other words, the chemical 

 characteristics of the soil influence the yield of crops, while the phys- 

 ical characteristics have generally the greater importance in determin- 

 ing the kind of crop adapted to the soil. 



This work will require much further investigation before these 

 statements can be definitely proved. But the amount and character 

 of the evidence so far obtained is such that these ideas may be taken 

 safely as working hypotheses. They are now serving us in this 

 capacity in suggesting and giving direction to studies which are con- 

 fidently believed to have far-reaching importance for agricultural 

 methods and practice, studies which in all probability could not have 

 been conceived or planned without the investigations which have just 

 been briefly outlined. The results of the work indicate, as might be 

 expected, that the composition of the soil moisture is largely influ- 

 enced both by the cultivation and by the cropping of the soil, and 

 appear to show in what way and to what extent cultivation can be 

 depended upon to change these important characteristics. 



The results of the last year's work also seem to indicate the very 

 superficial nature of the droughts which so seriously affect crops in 

 the Eastern and Middle Western States. It has been frequently 

 observed that in a time of drought, when the surface soil becomes 

 desiccated and the plants are suffering, the subsoil at a depth of 1 or 

 2 feet contains but little less than the average amount of moisture, 

 and it has frequently been observed that the crops are much more 

 shallow rooted than they are in the far West. This has been variously 

 ascribed to the uniform texture of the soils and subsoils in arid regions, 

 and to other reasons, but the true explanation seems to be that with 

 our frequent and excessive rains in the spring and early part of the 

 growing season, the crops find sufiicient moisture near the surface and 

 develop a superficial root system. When the drought comes and the 

 surface soil loses its moisture, the crop suffers because it is not pro- 

 vided with a deeper root system. In the far AVest, where spring and 

 summer rains are rare, the crop is planted upon a soil which is 

 always uniformly moist to a considerable depth, and with no subse- 

 quent rains the plant develops a deeper root system, which enables it 

 to survive long periods of drought that would seriously affect it if 

 it was subjected to frequent showers during the early period of its 

 growth. It is a familiar fact that a lawn which once is watered during 

 a dry season will have to be frequently watered or the grass will suffer 

 oftentimes more than if it had not been watered at all. The first 

 watering induces a superficial root development, which must be sup- 

 plied frequently with water. What can be done to prevent this tend- 

 ency and to overcome the effect of droughts is a subject of the utmost 

 importance, and one which will receive the attention it deserves. 



I know of no line of work which has been undertaken of more fun- 

 damental importance than the work of the division of soil manage- 

 ment, nor one which offers a i^romise of more valuable results to the 

 agricultural interests. When these fundamental problems have been 

 established they Avill give a reliable basis for the development of bet- 

 ter methods of cultivation, fertilization, and cropping. 



Tobacco Investigations. 



Since my last report the commercial success of the shade-grown 

 Sumatra tobacco in the Connecticut Valley lias been assured. Last 

 year 41 aicres of shade were erected by 13 farmers, cooperating with 



