Nothing says Earth Day, or spring for that matter, like planting a tree. It's a healthy practice that is synonymous with clean air and a renewal of life and nature. Whether in a natural setting or an urban environment, trees are magnificent living creatures that offer shade from the sun, food and shelter to thousands of organisms crucial to the fragile balance of life.

Trees have inhabited the Earth for about 360 million years, long before flowering plants were around (they came about 200 million years later). There are over 50 families of trees and hundreds more individual species. But as resilient as our woody, leafy neighbors are to have spread across continents and epochs, it still takes a little knowledge of species selection and proper planting techniques to have a sapling mature into a beautiful and healthy mature tree.

Step One
Select a healthy, structurally sound specimen with a nice single trunk. This promotes the growth of a central leader so that the tree can grow up strong and at its maximum rate. Take a look at the foliage and make sure there are no insects, disease or damage, which can weaken and even kill a young tree. Don't go for the biggest tree in the smallest pot, you're not getting a good deal. Make sure there are no roots poking out of the holes in the bottom of the pot and that there are minimal girdling roots, roots that circle the inside of the pot.

Step Two
Once the site is selected, dig the pit. Find the root collar, where the trunk flares into the roots. This will tell you how big the root ball is and how deep to dig the pit. Take the height of the root ball and dig the hole 90 percent of that. That's right, smaller than the root ball. This leaves room for the root ball to settle into the ground without going too deep. The root collar should always be above ground to promote a healthy growing tree. In addition to the depth, dig the hole two- to three-times wider than the root ball. This gives you room to work without damaging the roots. Save the dirt.

Step Three
Set the tree in the pit and orient the tree properly so that the trunk is vertical. Backfill a little soil around the base of the root ball to support it and then continue to fill in the hole with a third of the original soil and then wet it. There is no need to tamp or pack the soil. Add another third of soil, wet again and then finish off with the last of the soil and water one more time. Fill up the hole to the soil level and do not put soil on top of the root ball, which should be poking up just slightly out of the ground.

Step Four
Put about a four-inch cover of mulch over the root ball, making sure it does not touch the trunk. There should be no need to stake the tree unless you live in a windy area. If that is the case, drive the stake in the windward side of the soil, not the root ball, and use broad and flexible ties to put around the trunk, like an old bicycle inner tube. Attach the supports as low as possible on the trunk. Check the points of contact monthly to make sure the ties are not damaging the tree. If done properly, one growing season of staking will suffice.

Step Five
Watering is the single most important thing you can do to ensure the survival of your new tree. New trees need more water than established trees and irrigating regularly for the first three to six months is necessary. A slow soaking so that the water percolates deep into the soil is best, promoting deep root growth.

Before You Plant

Do Your Homework
Trees are environmentally specific. Before selecting a tree for your yard, take a walk around your neighborhood and make a list of all the trees that are thriving in the area. Then select the species youƒd like to be growing next to your home.

Function Over Fashion
Different species of trees have different shapes and therefore, different functions. Columnar trees make great wind and noise barriers, canopy trees afford shade from hot, midday sun and fruit trees provide us with a nutritious crop.

Think Long Term
In twenty years, a tiny sapling could become a widespread canopy tree. When selecting the right site to plant, think about the size the tree will grow to in a couple of decades. And watch out for overhead power lines.