Question

Trees grow by adding new wood outward from the center. When a tree is cut down, the series of rings in the stump of the tree tells how old the tree is. The light-colored rings represent the wood that grew in the spring and early summer. The dark-colored rings represent the wood that grew in late summer and fall. One light ring and one dark ring together represent one year of the tree's life. The first year of the tree's life is represented by the core of wood at the center of the tree plus the first dark ring.

The image below shows the rings of an oak tree planted in Boston, Massachusetts, in the spring of 1982. The tree was cut down in 2001.

diagram showing tree rings
Image courtesy of EPA
The graph below shows the average daily precipitation in Boston, MA, each year from 1982 to 2001. The year 1982 was the first year of the tree's growth.

graph showing average daily precipitation
Data courtesy of NASA
The oak tree had its largest increase in diameter in its
year. During this year, the average daily rainfall was
. The tree's rate of growth was very small in the tree's fourteenth year, during which average daily rainfall
.

According to the evidence, the amount of rainfall cannot be the only environmental factor that influences a tree's growth because the year with the most rainfall
.

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Answer 1

I can’t see the images you mention. If you upload the stump photo and the rainfall graph (or tell me which ring is widest and the rainfall value for each year), I’ll fill in the blanks exactly. Meanwhile, here’s how to find each answer and a ready-to-use template you can complete:

How to find the answers
- Number the rings starting with the core + first dark ring as year 1 = 1982. Year number n corresponds to calendar year 1981 + n. (So year 14 = 1981 + 14 = 1995.)
- The largest increase in diameter = the widest pair of one light + one dark ring. Count which ring number that is, then convert to the calendar year with 1981 + ring number.
- Read the average daily rainfall for that calendar year from the graph.
- For the fourteenth year (1995), read the average daily rainfall from the graph and note whether it was high or low.
- To show rainfall isn’t the only factor, compare the year with the most rainfall to the ring widths: if the year with the most rainfall did not produce the largest ring (or produced very small growth), that shows other factors matter.

Fill-in template (replace placeholders after you check the images/graph)
- The oak tree had its largest increase in diameter in its [nth] year (calendar year [1981 + n]). During this year, the average daily rainfall was [value].
- The tree's rate of growth was very small in the tree's fourteenth year (1995), during which average daily rainfall [was (low/medium/high)/was about (value)].
- According to the evidence, the amount of rainfall cannot be the only environmental factor that influences a tree's growth because the year with the most rainfall [did not correspond to the largest ring / showed only small growth].

If you upload the images or give me the ring counts and the rainfall values from the graph, I’ll complete the blanks for you.