Hi, 

We can see some fungal growth at the base of the trunk which is a sign of wood decay. We would recommend that you consult with an arborist or licensed tree expert if you are concerned about its safety for falling on anything. 

The holes in the trunk could be from a sapsucker, a type of woodpecker that will eat insects as well as the sap from the tree, or it could be a wood boring insect. Borers are often a secondary response to tree decline and once they are in a tree there isn't a curative control to eliminate them. When trees are unhealthy or stressed, borers come in to aid in the decay process. 

If it isn't in danger of falling on anything in your yard or near a driveway or sidewalk which it doesn't look like it is too close to anything, then you can let it decompose and fall naturally, offering a resource for insects, birds and other wildlife that benefit from decomposing wood. An alternative is to have the arborist remove the top and leave a good portion of the trunk as a stump to break down over time.

Emily