Wood is a fibrous and porous tissue found in the roots and stems of trees and other woody plants. Wood falls under the category of organic material, it is a natural composite of cellulose fibers that are strong in tension and embedded in a matrix of lignin which resists compression. Sometimes the definition of wood is represented as it is the only secondary xylem in the stems of trees, or defining it more broadly to include the same type of tissue elsewhere such as in the roots of shrubs and trees. Wood performs the function of providing support, in living trees, enabling them to grow large or stand up by themselves. It also acts as a medium to convey water and other minerals and nutrients between the leaves, growing tissues and the roots. Wood has been used for several purposes since a very long time for fuel, for making weapons and tools, as a construction material, for the manufacturing of paper and furniture. Not long ago it also emerged as the feedstock for the production of purified cellulose and its derivatives, such as cellulose acetate and cellophane. Forty seven percent of the growing livestock in forests worldwide was used for commercial purposes, as of the year 2005.
In this sub category you can download free PNG images: Wood Nature. In this category "Wood" we have 25 free PNG images with transparent background.