| A | B |
|---|
| outer bark | the very outside skin of the tree |
| phloem | inner bark that transports the nutrients to the leaves and outer tree parts |
| sapwood | the younger, softer active outer portion of the tree's wood |
| cambium | between the phloem and the sapwood, this living layer supports the tree's secondary growth |
| heartwood | the older, harder, nonliving central part of the wood |
| growth rings | the layer of wood a tree adds during a growth season, usually a year |
| early wood | the lighter portion of the growth ring at the beginning of the growth season, when it was wet |
| late wood | the darker portion of the growth ring from the end of the growth season when it was drier |
