Gavigan et al. 2025. The phenology of invasive Norway maples is unbe-leaf-able!
by Corey Gavigan, Jack Jacobsen, Jaiden Monteau and Dr. Allyson Jackson
Abstract
Phenology, the time in which seasonal changes occur in a plants life cycle, is based on several factors. To determine what factors had an effect on tree phenology we surveyed three different species of maple trees on campus. We looked at two native species, Red maple (Acer rubrum) and Sugar maple (Acer saccharum), as well as one invasive species, Norway maple (Acer platanoides). we used leaf color as an indicator for when a tree stopped photosynthesis for the season. Originally we found that Norway maples photosynthesize longer than native maples but not long enough that there was a statistical difference. To investigate further we combined data collected in a similar study last year with data collected this year. We then found that increasing the sample size showed that there is indeed a statistical difference between when Norway maple and native maples stop photosynthesis. The statistical tests prove that Norway maples continue photosynthesis later into the year. Norway maples continuing photosynthesis for longer means that not only do they continue to grow longer than native maples but they also sequester more carbon out of the atmosphere. The implication of these findings leaves us asking the question, do we remove the Norway maples because they are invasive or leave them be because they contribute more to the carbon cycle.