What r tree rings for?

Question

What r tree rings for?

Answer 1

A tree grows outward as well as upward.  As the main trunk grows, each ring is one year of growth.  You can actually determine weather patterns and other things by examining the rings.  Thick rings = good growing season

Thin ring = drouth or other seasonal impediments.  And yes, drouth is a correct spelling.

Answer 2

Variation in tree rings is due to variation in environmental conditions when they were formed and the rings mark each year' growth as new xylem tissue (wood) is produced.

Answer 3

Each ring represents a year of new xylem (water conducting tissue).  In the spring, the new xylem cells produced are large, which makes the lighter part of the ring.  By the time fall comes around, the cells are smaller and more compacted, making the darker part of the ring.