We all know what trees look like. Trees can be found in the forest, farms, gardens, and along the streets. When they are allowed to grow tall and big. They ate cut down to produce what is commonly called Wood or timber. Wood is one of the commonest and most widely used materials.
Wood is used in making furniture and cabinets. Here you will know more about trees and wood.
The major parts of a tree
The major parts of a tree are its roots, trunk, branches and leaves. These parts play different and Important roles in the growth of a tree.
Roots
Trees are held firmly to the ground by anchoring organs called roots. The roots of some trees can grow downwards to depths of 100ft or 30metres, roots Also absorb water and minerals through tiny structures called root hairs. From the roots water and Minerals are carried upward to the leaves.
Trunk and Branches
The trunk supports the branches. It raises them as high as possible towards the light. It is from the trunk that we get timber. If we cut across the trunk, we will see the cross section. Bark is the outer protective covering of tree trunks. Species of trees are identified by the colour and thickness of their barks. Most of a tree trunk is occupied by the wood which consists almost entirely of dead cells.
Leaves
Roots manufacture food for the tree in the presence of sunlight and air. The leaves consume some if the good and pass the rest to other parts of the tree. Leaves also help the roots to absorb water from the ground.
How a tree grows
Warm sunshine evaporates the moisture In the leaves. This causes a watery solution of minerals salts to be absorbed by the roots, and flow through the sapwood of the trunk and branches to the leaves. This watery solution is called sap. The action of the sunlight and air now turns these minerals salt in the leaves into a diet of starch and sugar. This then flows down through the inner bark to feed every part of the tree. Trees grow in both height and diameter. Some trees only grow to 4m while some may reach heights of more than 100m.
Types of wood
Samples of different types of wood are mahogany, hickory , cherry etc. They differ in colour. Density hardness and other properties. Mahogany is heavy. Iroko wood is resistant to rot and insect attack. Oak is highly durable.
When wood is used in the manufacturing industry and the wood trades, it is classified as either hardwood or softwood. It is not correct to think that hardwood is wood that is hard while softwood is wood that is soft. This is because there are some softwoods that are harder than hardwoods. How then can we differentiate between the two types? This is done by looking at :
I) the appearance of the growing trees, or
ii) the structure of the wood.
Hardwood or deciduous tree
hardwood or deciduous tree is grown in tropical regions like Nigeria.
Examples are Iroko, afara. Mahogany, opepe, Omo , etc. These trees produce the timbers used for our furniture and in construction. Their major characteristics is that they have broad leaves. The trees also shed their leaves every year.
Softwood or coniferous tree
These trees have needle like leaves. They are called coniferous trees or conifers because they bear naked seeds that are on cones. They do not shed their leaves like deciduous trees. They are said to be evergreen because their branches always bear green leaves. These trees produce the commercial softwoods. They do not grow in Nigeria but grow mostly in the temperate regions of the world. Examples are spruce, pines, cedar, cypress, fir, etc .
Differences between hardwood and softwood
Hardwood
Trees have broad leaves
Softwood
why trees have needle like leaves.
Hardwood
Short trunks and branches With busy heads
Softwood
Soft Straight and tapering stems.
Hardwood
Heavy and dark timber
Softwood
Relatively light timber.
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