Write a note on spring wood and autumn wood.

(N/A) $\rightarrow$ In the spring season,the cambium is very active and produces a large number of xylary elements having vessels with wider cavities.
$\rightarrow$ In the spring season,the number of leaves increases,so for efficient water transport,a larger number of vessels are required.
$\rightarrow$ The wood formed during this season is called spring wood or early wood.
$\rightarrow$ Spring wood is lighter in color and has a lower density.
$\rightarrow$ Autumn wood: In winter (or autumn),the cambium is less active and forms xylary elements that have narrow vessels; this wood is called autumn wood or late wood.
$\rightarrow$ Autumn wood is darker and has a higher density.
$\rightarrow$ Annual Rings: Spring wood and autumn wood appear as alternate concentric rings,which constitute the annual ring. Annual rings seen in a cut stem provide an estimate of the age of the tree.