This forestry key divides trees into those with needles or scale-like leaves versus those with broad or flat leaves. The pines, cedars, junipers, and firs are classified as conifers. They are differentiated from the broadleaves because they have needle- like leaves.
The broadleaves are distinguished because they loose their leaves in the late fall or winter. Broadleaf trees have large, flat leaves as opposed to the thin needles of the conifers. Examples of broadleaf trees are the maples, oaks, hickories, and elms.