Which direction does the denser side of a large tree's growth rings face, and what can growth rings tell us?

I. Which side do the denser growth rings of a large tree face

Generally speaking, the denser growth rings of a large tree face the shady side, that is, the north side. This is because one growth ring is one year's growth of the tree, and whether the tree grows vigorously depends on light conditions. For a large tree, the light conditions on the south-facing side are certainly better than those on the north-facing side, so the tree grows more vigorously on the south-facing side than on the north-facing side, and the growth rings on the south-facing side are wider than those on the north-facing side.

II. What can growth rings tell us

1. Direction: A large tree's growth rings are sometimes wide and sometimes narrow. The wide, sparse side of the rings shows that the tree grew well, and it faces the sunny side, that is, the south. The narrow, denser side of the rings shows that the tree grew poorly, and it faces the shady side, that is, the north.

2. Age: One growth ring is one year's growth of the tree. By counting the number of growth rings, we can judge how many years the tree has lived. However, if the temperature drops sharply in a certain year and then rises again, two growth rings may very likely appear in that year.

3. Climate: A large tree's growth rings are sometimes wide and sometimes narrow. If a large tree has many narrow growth rings and then suddenly one very wide growth ring appears, it shows that the local environmental and climatic conditions were relatively poor at first, so the tree grew slowly, and later the climate became suitable, so the tree grew rapidly and produced one very wide growth ring.