Tree
Hardwood and softwood
Hardwood trees are broadleaf trees such as oak and maple, and softwood trees are conifers such as pine, and the names do not describe how hard the wood is.
Hardwood and softwood are tree groups, not measures of hardness. Penn State Extension says the terms hardwood and softwood actually have little to do with the hardness of the wood itself. Softwood trees are gymnosperms, such as pines. Hardwoods have broad leaves and fruit, where softwoods have cones and needles.
The wood also differs inside. Penn State says hardwood contains pores or vessels while softwoods do not. Oak and maple are hardwoods. Pine and spruce are softwoods.
For stumps, species can matter for pricing and sprouting, but the name alone does not tell you how long grinding takes. Wood moisture, age and size matter too. Ask your estimate about unusual wood. See pine, oak and maple stump grinding and heartwood and sapwood.