The effects of crowdedness and shadiness on plant height of Solidago canadensis, Cirsium vulgare, and Aster prenanthoides

Methods: Two transects were laid down in the grasslands east of Stong Pond on two separate days. On Tuesday, October 14, 2014 samples were taken from the inner region of the grassland (I) and on Tuesday, October 21, 2014 samples were taken from the outer region of that same grassland (O). Every 5 metres along the transect, the heights of the nearest Solidago canadensis, Cirsium vulgare, and Aster prenanthoides found within 1m from the transect were measured from where the stem touched the ground to the highest point on the plant. Each plant’s level of shadiness and crowdedness around the plant was recorded. This was repeated for a total of 60 replicates (30 for each transect). This data was then used in ANOVA tests and Tukey post-hoc tests to analyze shadiness versus the average plant height of each different species. Next, correlation tests were used to analyze crowdedness versus plant height of each species. This experiment was done to test whether the amount of sunlight affects plant height and whether the amount of crowdedness affects plant height.