Tree rings show the impact on growth over an entire growing season.

"So we decided to use it in the garden, where kids can study the tree rings."

In cold years, growth slows and the tree ring is thin.

Tree rings are more visible in places where the seasons change between hot and cold.

The user must move the pod around on the tree rings.

However, under about 20,000 years the results can be compared with dendrochronology, based on tree rings.

Additional tree ring studied were conducted in 1938 and 1964 expanded that knowledge.

These were interpreted as clear signals of the 1811-1812 earthquake series in tree rings.

Structures such as tree rings and the various tissues are often observed features.

Based on scientists' analyses of tree rings, ancient soils and other evidence, the answer is almost certainly yes.

As measured by its growth rings, one fallen tree was found to be 347 years old.

It has low, rounded ribs and the annual growth rings can be seen.

The stump is 4 feet wide and has 160 growth rings.

One thing is sure: the 530's were a tough time to be a tree, as the thin growth rings attest.

In the pit was growing a hemlock nearly 400 years old by the number of growth rings.

The thin, white shell is long and narrow with growth rings.

After checking its growth rings, he confirmed that it was 22 years old.

The true age could not be determined because Tambalacoque has no growth rings.

The surface is smooth and often has distinct growth rings.

They grow in the desert and do not have growth rings.