Hardwoods and softwoods are not actually defined by their hardness. If a tree produces a seed that has a coating or shell, like walnut or pecan, it is considered a hardwood. Generally, hardwoods have broad leaves like oak and softwoods are evergreens with needles like pine. The evergreens grow year round and develop much faster, producing softer wood. Broad leaf trees that grow slower and stop to shed their leaves in the winter take their sweet time to produce harder, more dense lumber. There are, of course, many exceptions to the rule. Balsa, for example, is botanically a hardwood, but the trees grow very quickly in tropical climates and produce some of the lightest, softest lumber in the world. On the contrast, red cedar, which is a softwood of the pine family, is harder than several hardwoods, even some species of mahogany.