Shrubs differ from trees in that they are shorter and have multiple, woody trunks. Identifying shrubs requires looking closely at their leaves, trunks, flowers and fruits with a good plant book in hand.
Leaves vs. needles
Many conifers, especially junipers, come in shrub form. They will not have leaves at all, but rather scales or needles.
Leaves on shrubs come in a variety of shapes, sizes, texture and colour. For instance, holly has bright green, spiny leaves, while one variety of Japanese maple has purple palmate (shaped like an open hand) leaves.
The multiple woody trunks of shrubs come in a variety of colours and textures, such as rough or smooth. Red osier dogwood is often planted since its smooth branches provide a dash of bright red during the winter.
Some shrubs, such as willows, have catkins instead of flowers. Many shrubs, such roses, hibiscus and forsythia, have distinctive, easy-to-identify ornamental flowers.
Some of the fruit on shrubs will hardly be noticeable while others become quite ornamental, such as holly berries.