Paragraph on “Formation of Wood” complete paragraph for Class 9, Class 10, Class 11 and Class 12

Formation of Wood

Probably the first use that man found for wood included burning it for heat or for shaping crude weapons. Today the uses of wood are unlimited and we would not be able to make many things including this book if it were not for wood. Wood comes from trees and trees grow from plants. The stem of a young plant contains vascular bundles in the shape of rings. Each one of these vascular bundles contain tissue which conduct water through the stem. These tissues are called Phloem and Xylem. Separating these two types of tissues is a wall called ‘Vascular Cambium’, as the cambium wall grows the plant stem begins to become wooden. At this stage the cambium divides to form new rings of xylem and phloem. This produces a fresh cylinder inside the stem and it makes the stern thicker. Xylem cells are tough, as pared to phloem, and they have thicker walls, this further strengthens the walls of the stem. As this process continues over the years the stem of the plant grows thicker to become the trunk of a tree. Over the years the inner rings become hard and give the tree trunk its strength. Hardening of the inner rings also blocks the pores thus preventing the flow of water, which at this stage, is left to the outer sap wood. The outermost layer of the tree is tough and scaly since it is covered with a layer of dead and waterproof cells called ‘bark’ which prevents loss of moisture from the tree trunk. Trees grow only in the summer months and in spring. In spring new xylem cells are produced by the cambium, with the passage of time these cells become smaller and a bigger ring of cells gets created on the outer side. These cells begin to show as a separate ring. As the process continues new rings are formed, one each year. It is for this reason that counting the rings in a tree’s trunk tells us the age of the tree. Constant formation of new rings, compresses the inner ones and wood is formed.

Determining the Age of a Tree

If we closely inspect the stump of a tree. which has been cut, we would See that it is made up of a series of rings, one located within the other. These rings signify the growth and age of the tree. Since trees form new walls of cells once a year and these walls get compressed to form the rings inside the trunk, the number of rings signify the number of years the tree has existed.