The lighter wood, sapwood, accounts for the annual rings that appear like concentric bands in the cross-section of tree trunks from temperate climates. Heartwood cells add strength and structure to a tree with their tough, fibrous mass. Darker wood, called heartwood, is at the center of the tree where xylem cells eventually enter a state of perpetual dormancy and become dead parts of a living tree system (much akin to human hair and fingernails). The vessel elements, acting as the conduits for movement of the sap, come in various lengths within a tree and among species. Wood fiber cells are smaller in length (0.7 to 3 millimeters) and diameter than softwood tracheid cells and do not participate in the living tree's fluid transport. In contrast, hardwoods, such as oak, have two kinds of wood cells: wood fibers and vessel elements. This open cell structure means softwoods a generally more receptive to preservative treatments.In softwood trees, such as pine, wood is composed of long (3 to 5 millimeters) tracheid cells that allow movement of the sap. In comparison softwood cells are open, they have long narrow cells (tracheids) which carry water and nutrients throughout the tree. The fibres on radial surface of a hardwood give strength. Because hardwood cells are closed and cannot function as conduits these vessels carry water and nutrients along the length of a tree and act as pipes to the outer layers of wood a growing tree. Spotted gum - a hardwood Hardwood and softwood microstructureĪn essential characteristic of a hardwood tree is the presence of vessels (pores or hollow ‘pipes’). Known as an angiosperm, a hardwoods tree grows seeds that have a covering like a shell or a fruit which grows into flowers. Hardwoods, like Spotted Gum, Blackbutt and Ironbark are broad leafed, deciduous trees which grow flowers with fruit and lose leaves annually. Hoop Pine - a softwood Hardwoods - appearance & reproduction Common softwood species include Radiata Pine, Hoop Pine and Cypress Pollinated trees will then create seeds that are carried by the wind to grow elsewhere. Known as gymnosperms softwood trees reproduce by growing cones which emit pollen. Softwoods are conifer trees with needle-like leaves that remain evergreen, they grow cones that have seeds. The differences are actually botanical and related to plant reproduction. In fact both types of timber are used for a variety of building projects from decorative to structural and the words hardwood or softwood don’t relate to the hardness or softness of piece of timber. So you’re choosing timber and you think the choice is pretty simple - you’ll need hardwood for the tough jobs and softwood for lightweight roles. Hardwood vs Softwood Timber posted: 14/May/2015
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