July 11, 1902.] 



SCIENCE. 



57 



able the Southern agriculturist to more 

 generally diversify crops. 



We have been told at former meetings 

 of this Association, by members of other 

 Sections, that within a comparatively short 

 time the United States will not be able to 

 grow the amount of wheat, and possibly 

 other cereals, needed for consumption. 

 These statements are based on our present 

 yields and the increasing demands of popu- 

 lation. If the figures are true it would 

 seem important, therefore, that attention 

 be drawn to the securing of varieties of 

 wheat better adapted to existing conditions 

 and yielding larger quantities of gTain. 

 This is a perfectly legitimate field for ap- 

 plied botanical work, and what has been 

 accomplished already indicates that much 

 can be done in the direction of largely in- 

 creasing the possibilities of this country in 

 the matter of cereal production. What is 

 true of cotton and cereals is also true of 

 many other crops, so that it is unnecessary 

 to go into detail as to what might be ac- 

 complished in the way of causing not only 

 an increased output, but improving the 

 quality of the output as well. 



Associated with the work of plant breed- 

 ing, and more or less closely related to it, 

 is another important field which has for its 

 object the studies of life histories of prin- 

 cipal crop plants, with a view of determin- 

 ing the environmental conditions necessary 

 for successful growth. This work, of 

 course, covers a broad field, as it involves 

 knowledge of the requirements of climate 

 and soil, and really merges into the broader 

 territory of ecological work. The prob- 

 lems involved carry with them, not only 

 the question of plant adaptations, but the 

 matter of introducing new plants from 

 foreign countries and the broader dissemi- 

 nation of plants already existing here and 

 which give promise of more profitable yields 

 under changed conditions of environment. 



AVith proper studies of soil and climate. 



the possibility of more intelligently defin- 

 ing the areas adapted to certain crops will 

 become greater. After all, however, the 

 vital questions involved in this problem 

 will depend largely upon actual experimen- 

 tation, as those most familiar with success- 

 ful crop production know how unsafe it is 

 to generalize in such matters. The success, 

 or failure in growing a certain crop oftera 

 depends on differences in soil and climate 

 so slight that present instruments cannot 

 determine them, although the plant, with 

 its power to respond to unmeasurable 

 stimuli, can do so. 



In the field of pathology the opportuni- 

 ties for applied work in the near future 

 will be great. We are all agreed that the 

 more or less empirical methods of handling 

 plant diseases has about reached an end. 

 It served a useful purpose in pointing out 

 practical ways of controlling some of the 

 common and destructive plant maladies, 

 and enabled those who were looking to the 

 future to create a sentiment making pos- 

 sible better and more far-reaching work. 

 We do not agree with those, however, who 

 hold that the time is at hand when we can 

 afford to stop the propaganda of actual 

 field treatment. In fact, we are more and 

 more convinced that one of the greatest 

 opportunities for bringing home the prac- 

 tical value of pathological studies will be 

 to undertake at once, on an extensive scale, 

 what may be called demonstration experi- 

 ments. A propaganda in this field, con- 

 ducted by and depending upon publica- 

 tions alone, no matter how practical such 

 publications are, will necessarily be slow; 

 but when the work can be carried into the 

 field and be made to serve as an object les- 

 son, the impression made is lasting and con- 

 vincing. 



One of the problems, therefore, for the 

 future, in this work, is how to insure the 

 application of the investigations made and 

 to so conduct the work that it will all go 



