Question

What is a tree line?

Answer 1

Definition:

Tree line is the boundary or an edge of the habitat where trees are capable of growing but beyond which trees do not grow. It is also called timber line.

Description:

The growth of the trees is inhibited beyond tree-line because of the following environmental conditions:

$\bullet$ Lack of moisture
$\bullet$ Cold temperature
$\bullet$ High altitude

Beyond the tree line, trees show stunted growth and form dense mat of bushes.