Professional forester and natural resource consultant Steve Nix describes scale-like leaves, needles and typical leaves with a leaf stalk, veins and a midrib in discussing how these leaves play a part in identifying trees. Nix explains that typical leaves usually come from hardwood and deciduous trees, which may form lobed and unlobed leaves when they come from simple tree leaves.
According to Nix, unlobed tree leaves have no projections around the margins of the leaf and may or may not have "teeth." Lobed leaves have major projections that shape the leaf and come as either balanced or unbalanced. Furthermore, with a balanced lobed leaf, the lobes may branch off in either a palmate or pinnate manner. Compound tree leaves have secondary leaves borne on a single stalk attached to a twig and may also branch off in a palmate or pinnate manner.
Nix also explains that trees with needles may either form clusters or bundles of needles or the single needles directly and singly attach to the twig. Evergreen, scale-like leaves often grown on cedars or junipers. Cedar leaves typically have scale-like green sprays that flatten into fan-like foliage. However, junipers usually have spiny, needle-like leaves that have berrylike, bluish, glaucous and bloomy cones on tips of shoots.