This time I would like to talk about double-top pine trees. What typically happens is, the top of the tree is broken off, maybe in an ice-storm or high wind, and the top-most branch takes over to be the new tree top. Sometimes multiple limbs try to compete to be the new top. This causes a fork in the tree… a double top.
Now, 20 years later, you have two tree tops touching each other, each obstructing the other from growing inward, and so a cavity forms between the two tree tops. The cavity then fills with rain water, which freezes and expands, which enlarges the cavity, allowing more rain water to enter, and so a cycle is created that ends with the tree splitting and one of the tops breaking off and falling. If a house happens to be nearby, look out!
So… next time you are out in your yard, or visiting friends and family, take a look around the property. If you see any multiple-top pine trees in close proximity to the house or activity area, an arborist should be called to inspect the tree for safety.