Botanically speaking, shrubs are multi-stemmed woody plants that grow shorter than trees. Depending on their growing conditions, some plant species that are considered shrubs can grow as tall as trees. Habitats made up mostly of shrub-type plants are called scrub or shrubland and are classified by how dense the vegetation cover is. For example, a closed-scrub habitat has denser foliage than an open-scrub ecosystem.
We tend to think of plants as stationary, but vines can "travel" by sending out branches, coils, and tendrils to grab hold of whatever is handy, then filling out leaves and stems in that direction.The searching tip of the vine is tender, but once the plant has a good anchor point, the stem grows thicker and tougher, in some cases enveloping the support completely.