Trees:

* Single, tall trunk: Trees have one main trunk that rises up from the ground and branches out at a certain height.

* Greater height: Generally, trees are much taller than shrubs, reaching heights of at least 13 feet (4 meters) or more.

* Longer lifespan: Trees usually have a much longer lifespan than shrubs.

* Woody stem: Both trees and shrubs have woody stems, meaning they are made of hard, fibrous material.

Shrubs:

* Multiple stems: Shrubs have multiple stems that originate from the ground.

* Lower height: Shrubs are typically shorter than trees, ranging from a few inches to 10 feet (3 meters) tall.

* Shorter lifespan: Shrubs usually have a shorter lifespan compared to trees.

* Woody stem: Similar to trees, shrubs also have woody stems.

It's not always easy to distinguish between trees and shrubs:

* Young trees: Young trees may appear similar to shrubs, with multiple stems. However, they will eventually develop a single, dominant trunk.

* Dwarf trees: Some trees are bred to stay small and may be confused with shrubs.

* Large shrubs: Some shrubs can grow quite large and may resemble small trees.

Ultimately, the distinction between a tree and a shrub isn't always clear-cut. But the general size and structure provide a good starting point for identification.