Dendrochronology is the study of

Given below are two statements: One is labelled as Assertion $A$ and the other is labelled as Reason $R$:
Assertion $A$: Late wood has fewer xylary elements with narrow vessels.
Reason $R$: Cambium is less active in winters.
In the light of the above statements,choose the correct answer from the options given below:

Bark $= .....................$

The characteristic feature of porous wood is represented by the presence of .........

Define bark.

Sapwood differs from heartwood in being: