Kind: captions
Language: en
when a tree grows it encodes information
into its wood kind of like a living book
each year a tree grows thicker by adding
a layer of new wood so if you slice
through the trunk and look at these
layers which appear as rings you're
looking at a record of how that tree
grew year after year
let's take a closer look at how the
Rings form under a microscope you can
actually see the individual cells during
the growing season the new cells are
large and thin walled we call this early
wood and it forms the lighter part of
the ring then as the days become shorter
the tree starts to prepare for winter by
producing cells that are smaller and
thicker walled
we call this late wood and it forms the
darker part of the ring in winter the
tree stops growing all together and
stays dormant until spring but that's
not all the tree rings can actually tell
us something about the environment that
the tree was growing in when conditions
are favorable the tree rings are fatter
and when resources like water and the
sun's energy are scarce they're thinner
what that means is that really old trees
can actually tell us something about
what the climate was like even before
humans had records
you