Memoirs Author:Brooklyn Botanic Garden Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: WEATHER CONDITIONS AND PLANT DEVELOPMENT GEORGE P. BURNS Vermont Agricultural Experiment Station The effect of weather conditions on plant development has... more » been one of the chief problems studied during the past few years by the ecologist, the agriculturalist, the forester and in some cases by the plant physiologist. The weather, however, is a variable mixture composed chiefly of different amounts of light—direct, diffuse, white, yellow, red, etc., or darkness; moisture—precipitation, humidity, soil-moisture, etc.; heat, temperature of the air and soil; wind, etc. Each of these component parts varies within short intervals of time and each has its effect direct or jndirect on the living plants. The problems of the effect of weather conditions, then, is largely a physiological problem and such problems should be attacked only by means of accurate experiments under controlled conditions. The ecologists have been attempting to change from the old descriptive methods in which the results of a more or less accurate study of the vegetation of a given area were published. Sometimes this study was accompanied by a few tables of meteorological data gathered from a nearby U. S. Weather Bureau station. In only a few cases were attempts made to relate these data to the descriptive part of the study and one was often at a loss to know why they were included in the publication. This type of work has served a good purpose in a preliminary way but is now outgrown. More accurate methods have been introduced by advanced workers and ecologists have adopted the plan of gathering their own data with instruments placed in the field, the attempt being made to place them under the same weather conditions as those of the plants under consideration. The largest amount of data has been collected ...« less