Root barriers work to keep damage from occurring to sidewalks, asphalt, retaining walls, etc. No matter how much you love trees, nearly everyone will admit that they are necessary to stop tree roots from wrecking pavements, etc.
Talk a niece leisurely stroll through a forest, national park, or even your own back yard, and you can't help but be impressed by the graceful and elegant beauty of trees. Their lush greenery and dappled shade are a pleasure just to look at. Also, adding trees to a landscape can enhance the value of your property.
But while all of the above is nice, remember that tree roots can be one of the most aggressive and powerful forces that Mother Nature can conjure up. When located near concrete, asphalt, foundations, or retaining walls, they can cause mass destruction and expense. Once the damage is done and you have to make repairs, the trees, no matter how lovely, don't look so appealing anymore.
Root Barriers
You can save yourself a lot of inconvenience and money by using root barriers. It's the eternal search for water, oxygen and nutrients that makes tree roots break through the ground and concrete too. If you could look underground you'd be amazed to see that a tree's roots can expand until they are two to three times the diameter of a tree's canopy. Since the roots naturally keep growing with the tree, they continue to increase in size until they are pressing ruthlessly against the concrete or asphalt.
A long time ago, the basic solution to keep tree roots from causing destruction was to choose certain species of trees that it was known were sturdy enough to grow in suburbs and cities, but which had less surface roots. That meant that maples, American elms, and sweet gums were out.
If you wanted a solution other than tree selection, then the only thing you could do was to have the tree root pruned on a regular basis, or you could replace it altogether. Since root pruning is expensive due to the time and equipment involved, most cities preferred not to do that.
It wasn't until 1976 when the first of many types of root barriers was designed. This lead to the creation of an actual science called tree root management.
Palm Trees
While it took some time for the concept of root barriers to catch on, nowadays it's widely accepted especially in states like California and Florida where palm tree removal had been the only way to control root growth and expansion from the many palm trees stationed around the states.
While palm trees are beautiful to look at, and have certainly become the symbol for some states such as California and Florida, their roots can be troublesome. For years it was accepted that the only thing to do when the situation got to be unmanageable was palm tree removal. That left the dilemma of whether or not to plant new ones where the old ones had been or select another type of tree that would have roots that were more controllable.
This wasn't really a practical solution in areas such as Florida and California where palm trees were deemed essential to the culture of the area. The public simply wasn't going to surrender its palm trees without a fight, so it was back to palm tree removal as the preferred and probably only solution.
The root barrier concept was a welcome relief to these states as it enabled the cities to avoid the constant expense of either pruning tree roots or having to resort to palm tree removal. Now the people could have as many palms as they wanted and the cities knew they could handle it.