Search

The article discusses the climatic cycles and treegrowths in the U.S. It highlights the ecologist interest in the correlation of treegrowth rainfall. According to that author, in dry climates, the ring thickness is proportional to the amount of rainfall in the year with an accuracy of seventy percent. It says that the trees were tabulated in groups of 10 or more, but a remarkable correspondence exists between individual trees of each group. It also says that double rings in the arid regions were found to be correlated with deficient winter snowfall, so that the tree had not enough water to continue forming its summer wood, and passed to forming autumn wood before the summer rains enabled it to start a fresh zone of wide elements.