Although you can identify a shrub by its many other characteristics, such as its flowers, fruits or nuts, bark and growth formation, the leaves usually provide the most accurate identification. There are several leaf characteristics you can study in order to identify a shrub. Identifying a shrub by its leaves isn't as difficult as it seems, even for the untrained eye. If you're trying to identify a shrub that's native to your region, reference a plant field guidebook. You can usually obtain a field guide at your local agricultural extension office.
Identify Conifer Shrub Leaves
Look for scale-like evergreen leaves that have branchlets emerging from a single stem into a slightly flattened, broad formation. Arborvitae and false cypress (Hinoki cypress) are among the conifer shrubs with scale-like leaves.
Identify evergreen shrubs with "awl"-like leaves by their alternating branchlets that create a spiky leaf formation. Junipers are the most common evergreen conifer shrubs with awl-like leaves.
Identify conifers with needle-like leaves to make your shrub identification. If the shrub has needle-like leaves, it's likely a yew (Taxus), fir or dwarf spruce.
Identify Broadleaf Shrubs
Decide whether the shrub has deciduous or evergreen leaves, meaning whether the shrub drops its leaves in winter or does not. Look on the ground around the shrub to see dead, fallen leaves if you're unsure whether the shrub is deciduous. Common evergreen broadleaf shrubs include boxwoods, hollies, rhododendrons and mountain laurels.
Determine whether the shrub's leaves are alternate or opposite. Opposite leaves grow directly across from one another on the branch, while alternate leaves grow in an alternating fashion along the stem.
Look at the shrub's leaf arrangement to determine whether they're simple, meaning that each leaf is attached directly to a branch by a stem, or compound, where the leaves are divided into leaflets on the stem.
Identify the shrub by its other leaf characteristics, such as whether the leaves are lobed and whether they have toothed edges. Shrubs with lobed leaves include the flowering currant, ocean spray, vine maple and sweet gum, while those with toothed margins include the red huckleberry, Nootka rose and evergreen huckleberry.