Sugar Babies

Students develop science process skills as they work with data from the Hubbard Brook Experimental Forest to answer the question, “What influences the survival of sugar maple seedlings?” Sugar maples are an important component of the forests in Northeastern and North Central United States. They are valued by people for their foliage, beauty, and sweet sap. At Hubbard Brook Experimental Forest in the White Mountains of New Hampshire, scientists are gathering data to find out what influences the survival of sugar maple seedlings.

This exercise not only asks students to graph data in a scatter plot but also to analyze and evaluate the results. Part of the analysis has students use Excel to fit a trend line and calculate an R2 value for the data. When data points are scattered over a graph, a trend line can be helpful in identifying whether any trend exists. An R2 value tells how well the trend line describes the data. It is a descriptive value between 0 and 1; the closer an R2 value is to 1, the better the trend line fits the data points. Please note that R2 does not denote whether a relationship is significant. Significance is a statistical term that goes beyond the scope of this lesson.

Classes appropriate for: advanced high school ecology and environmental science classes.