Balance is important for everyone but becomes particularly significant as we age. Tree pose provides a chance to make good habits in how you distribute your weight on your feet. It is also a good way to practice focusing your gaze in a particular place; this is known as drishti and is incorporated into many balances in yoga (and other poses as well.)
In her fitness blog, New York Times journalist Gretchen Reynolds suggests that you make a habit of standing on one foot while you brush your teeth… so to work on balance, strike a low tree pose whenever you pull out your toothbrush!
Here’s the full article about balance and ankles: