Investigating the effects of light intensity on Cirsium erisithales drooping angle in the Italian Alps
In the summer of 2022, on a field course in the second year of my Zoology degree, I had the opportunity to visit the Baita Torino field station in the Italian Carnic alps. We walked in groups around the surrounding area to explore the biota available. I noticed and identified a yellow thistle, Cirsium erisithales, which seemed to droop towards the ground, but at different angles in different individuals. I noticed that the differential droop seemed to coincide with the amount of light which the plant was subject too.
In preliminary tests I compared different individuals who were situated under canopy or not, thus experiencing differential amounts of light intensity. It seemed there was a relationship with droop angle towards the ground and the amount of light exposure.
To test this, I used a method using photography and ImageJ, along with a light intensity phone application, to compare different light intensities and the droop angle of the flower. However, upon statistical analysis there did not seem to be a significant relationship between droop angle and light exposure. Thus, I concluded that the differential amount of droop was most likely due to other factors including age, wind etc.
William Chipperfield 