In the telephony world, the term "phone tree" has at least two meanings. One refers to the list of options ("For Sales, press 1") that one must navigate when calling a large organization. Terms often associated with this type of phone tree include "purgatory" and "Hades".

Another type of phone tree is used by groups that want to share emergency alerts or other news to members of the group. The message may be an emergency notification or simply a reminder of a change in the practice field for the 10 year old fast pitch team. With this phone tree, an individual calls several members of the group who, in turn, calls several members of the group, and so on, until everyone in the group has received the message. This type of phone tree is also known as a call tree or calling tree.

For two or three years, I participated in arranging an annual call tree for a local volunteer organization with several thousand members. We wanted to see how many members of the organization could be contacted on a given Saturday as a test of how effective we might be in contacting these people in an emergency.

The organization was divided into 10-12 groups. The head of each group was to determine the best method to call the people in their respective groups. Some groups had one person call several people and those people, in turn, called several other people. At least one group had just a few people each contact many people.

What we learned from these tests was that the groups that reached the most people were those groups where a few people made many calls, as opposed to the groups where many people made just a few calls each. This is because the latter method has more potential points of failure.

Here are two additional suggestions to give your call tree even higher success rates. The first is to automate your call tree. Using a hosted or SaaS solution, you can send thousands of emergency alerts for just pennies per delivered message. The second suggestion is to contact people using multiple modes simultaneously, such as home phone, office phone, cell phone, email and SMS text.

No matter what you name it, a call tree is only effective if it delivers messages quickly, accurately, and inexpensively, and if doing so depends only on one person setting the process in motion.