362 



BRIEF SUMMARY OF CONCLUSIONS. 



Some of the principal points that have been brought out in this 

 collection of data will seem like the expression of ideas that have 

 long been known, yet whose importance has probably been under- 

 rated by those who desired to deduce definite numerical relations 

 between the climate and the crops of any locality. 



(1) We have seen that in a general way the plant, like every other 

 living being, adapts itself, when possible, to its climatic surroundings, 

 and therefore will produce some crop, if possible, the first year and 

 will do better and better in the next few succeeding years if the 

 seasons are not too severe. 



So sensitive is the plant to a change of environment that the ordi- 

 nary seasonal irregularities from year to year have a strong influence 

 upon it, so that the general disposition acquired by the seed in a 

 single dry or wet, or cold, or early, or late season prepares it for a 

 corresponding dry or wet, cold, early, or late season next year. Or, 

 again, a " sport " that has unexpectedly developed under the special 

 influence of a given season and soil, and has acquired to a high degree 

 characteristics which make it harmonize with that season, becomes 

 the progenitor of some important variety whose adoption may, in a 

 few years, revolutionize the agriculture of that region. The weather 

 of any growing season affects the crops of future years by modifying 

 the seeds of the current crop. The current season and the resulting 

 seeds must harmonize together. 



(2) If, instead of adapting the plant to the climate, we, for 

 instance, plant the seeds proper for a moist climate in an arid region, 

 and if we must therefore artificially irrigate in order to secure a 

 crop, such irrigation should be looked upon, not as establishing an 

 expensive custom to be adhered to in future ages, but as simply a 

 temporary device to be managed in the interests of the evolution of 

 new varieties that can eventually be cultivated in that soil and cli- 

 mate without irrigation. This is the result that nature has herself 

 frequently achieved by the slow process of carrying seeds, step by 

 step, from moist to arid regions, and which man endeavors to hasten 

 when he carries seeds by railroad and steamship from England to 

 our arid region. 



(3) Inasmuch as the cultivation of the cereals cotton, tobacco, 

 sugar, and other important crops will hardly be attempted except in 

 regions where the climate is known to be reasonably in harmony with 

 the seed that is planted, therefore we may assume that an average 

 crop is certain under the average climatic conditions. The departure 

 of any special season as to climate will produce a corresponding 

 departure as to crop, but the latter must be expressed as a percentage 

 of the average ordinary crop, and not simply in absolute measure, 



