Hard and Soft Woods
There is a strong relationship between the properties of wood and the properties of the particular tree that yielded it. The density of wood varies with species. The density of a wood correlates with its strength (mechanical properties). For example, mahogany is a medium-dense hardwood that is excellent for fine furniture crafting, whereas balsa is light, making it useful for model building. One of the densest woods is black ironwood.
It is common to classify wood as either softwood or hardwood. The wood from conifers (e.g. pine) is called softwood, and the wood from dicotyledons (usually broad-leaved trees, e.g. oak) is called hardwood. These names are a bit misleading, as hardwoods are not necessarily hard, and softwoods are not necessarily soft. The well-known balsa (a hardwood) is actually softer than any commercial softwood. Conversely, some softwoods (e.g. yew) are harder than many hardwoods.
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Famous quotes containing the words hard and, hard, soft and/or woods:
“It is quite gratifying to feel guilty if you haven’t done anything wrong: how noble! Whereas it is rather hard and certainly depressing to admit guilt and to repent.”
—Hannah Arendt (1906–75)
“Conceptual relativism is a heady and exotic doctrine, or would be if we could make good sense of it. The trouble is, as so often in philosophy, it is hard to improve intelligibility while retaining the excitement.”
—Donald Davidson (b. 1917)
“I’ve sometimes thought ... that the difference between us and the English is that the Scotch are hard in all other respects but soft with women, and the English are hard with women but soft in all other respects.”
—J.M. (James Matthew)
“What a wilderness walk for a man to take alone! None of your half-mile swamps, none of your mile-wide woods merely, as on the skirts of our towns, without hotels, only a dark mountain or a lake for guide-board and station, over ground much of it impassable in summer!”
—Henry David Thoreau (1817–1862)