The study looked at how the amount of chlorophyll in an oak tree affects its ability to photosynthesize throughout the year. They found that the tree had the highest photosynthetic rate in March, May, and September, and the highest chlorophyll content in April, October, and December. When the tree had low chlorophyll levels in July, its photosynthetic rate also decreased. However, there were some times when the chlorophyll levels were high but the photosynthetic rate didn't match. Overall, the tree's photosynthetic system stayed mostly intact even during stressful periods.