Some trees are more prone to storm damage than others, often due to their basic growth habits. A classic example in the northeastern United States is the Bradford Pear. The growth habit of the tree causes it to form steep "V-shaped" branch crotches. This structural weakness, combined with weak wood from rapid growth, combine to make these ornamental Pears extremely vulnerable to hurricanes or damage from high winds.
Trees have different root structures and some, like Oaks, create deep tap roots. However, most trees have the majority of their roots in the top 12 to 18 inches of the soil. As some author once said, it's almost as though they "are sitting on a dime." And when you combine shallow roots with rain-soaked soil, it is easy to end up with a windthrown tree.
Unfortunately, either to save time or due to lack of knowledge, many trees have their fates sealed for them the day they are planted. Synthetic burlap, often called Leno, is a handy product for nurserymen since it allows them to hold balled-and-burlapped trees much longer than when the earth balls are wrapped with burlap. While regular burlap rots away in one year, synthetic burlap lasts much longer.
In most cases, it lasts way too long if it isn't removed at the time of planting, since it constricts roots and weakens a tree's resistance to high winds. If you ever plant a tree with the earth ball wrapped in synthetic burlap, be sure to cut-away as much of the material as possible, because it not only constricts future root growth, it can also girdle (choke) the tree trunk. How do you know if it is synthetic burlap? The flame from a lighter will cause it to melt like plastic, instead of burning like cotton fabric.
Decay - If you see any sort of conk (mushroom looking structure) growing out of a tree trunk, it indicates there is decay within the tree trunk. This will weaken the integrity of the wood in high winds.
The one word answer to that question is THINNING. Picture an old sailing frigate like the one you saw in the movie "Pirates of the Caribbean." That sailing vessel had several masts, and each mast contained several sails. In order to catch the most wind, all the sails were set so they could catch the wind.
Now visualize an evergreen tree with rows of branches up and down the tree trunk. These branches are very similar to those sails, each catching some wind instead of allowing the wind to pass through. The point being, that if you eliminate some of the branches, the tree will have less "sails" to catch the wind.
If wind can pass through a tree more easily, it is much less likely to get blown over in high winds. Therefore, thin your trees with a pole pruner to help protect them from tornadoes, hurricanes and other strong storms.
Notice the similarities between these two images: