ESHS/HSS Annual Meeting

More Light! Biologizing Plant Growth, 1860s-1890s

• In Event: Managing Complexity: Investigating Plants, Forests, and Oceans in Late Nineteenth-Century Germany

English Abstract

Throughout the nineteenth century, plant physiologists devoted considerable thought to the influence of environmental factors on plant growth and development for both theoretical and practical reasons. By the 1860s, it had become apparent that light was potentially the most significant factor in this regard. However, identifying patterns and regularities that could inform further physiological studies, as well as agricultural or horticultural practices, proved extremely difficult.

One scholar who addressed this issue was Julius Wiesner (1838-1916), a plant physiologist from Vienna whose career spanned various foundational and applied areas of science. When he took his research out of the laboratory and into the field to study the impact of light, Wiesner realized that light intensities were much higher outdoors and that the amount of light a plant received varied dramatically depending on various factors, ranging from its micro-environment to its geographical location. To overcome these challenges, Wiesner developed new techniques for measuring light intensities, defined new concepts to describe these phenomena, and adopted new methodological standards to cope with the complexity of nature, and to accommodate both scholarly and practical purposes. This approach was highly successful, as demonstrated by its widespread adoption in fields such as horticulture and gardening, forestry, and photography.

Author

• Kärin Nickelsen, History of Science, LMU Munich