Tree Diagram

A tree diagram presents a map of the tasks you need to accomplish to solve a problem, achieve a goal or resolve an issue.

When do we use a tree diagram?

Use a tree diagram when you want to:

• map out the path and tasks that need to be accomplished in order to achieve a primary goal and all related sub-goals;
  
  
• organize the sequence of tasks in an implementation plan; and
  
  
• check the logic in a plan by looking for possible gaps.

How do we make a tree diagram?

Completing a tree diagram consists of five (5) major steps:

Step 1: Start the tree diagram session

•  Set a time limit for the session. Generally, 45-60 minutes is sufficient.

   Note: Plan on taking more than one (1) session to complete the tree diagram.

• Select someone in the group to be the recorder. The job of the recorder is to write potential tasks or process steps on a flip chart, sticky notes, or 3” x 5” cards.
  
  
• Identify your goal. In your team or work group, agree on a simple statement describing the corrective action or problem solution to be implemented. Write this statement in the box on the left side of the diagram.
  
  
  
  

Step 2: Brainstorm tasks

Your job now is to brainstorm about all the steps or tasks that need to be accomplished to reach the identified goal.

Step 3: Identify major tree headings

When you have completed the initial brainstorming (this could take the entire 45-60 minutes), choose the tasks you consider the most important (e.g., researching the cost, hiring new employees, choosing a vendor, etc.). These tasks are called major tree headings and are the first or broadest level of detail on the Tree Diagram.

• Place these three (3) to four (4) tasks (listed on the 3” x 5” cards or sticky notes) immediately to the right of the statement or goal you identified in Step 1.

  Note: These tasks will now become your group’s focal point.

Step 4: Create the next level of detail

The major tree headings you choose in the previous step now become sub-goals. All the other brainstormed tasks that fall under these tree headings should help you reach these sub-goals.

Note: It may be necessary to brainstorm additional tasks at this point.

Select the tasks that must be accomplished in order to reach the sub-goals, and line them up to the right of the appropriate major tree heading (sub-goal). These tasks should be in sequential order.

Hint: Ask the question: What tasks do we need to complete to get to the major tree heading (sub-goal)? Continue this process until all levels of detail are arranged on the tree diagram (i.e., all individual tasks are sorted and placed appropriately on the tree diagram).

Step 5: Review the tree diagram

Check for any gaps in logic, or things that just don’t make sense, on your tree diagram. Do this by reviewing each “branch.” Start at the far right of the diagram, since these are the tasks that need to be completed first.

Hint: To check the sequence of tasks, ask the question: “If we complete this task, will it lead us to the next task on the Tree Diagram?”

• Additional activities, above and beyond checking for gaps in logic, can be accomplished in this step. For example, you could review the tree diagram with other groups or departments to get different viewpoints.
  
• Revise the tree diagram if your review necessitates changes.
  
• Make any necessary action assignments (e.g., communicate responsibilities, clarify responsibilities, etc.).

Decide On Next Steps

Once team members, different departments, customers, and suppliers have reviewed your tree diagram, additional steps need to be determined.

Possible next steps include:

• Assigning responsibility to carry out tasks
  
• Setting deadlines
  
• Deciding on measurements to determine the effectiveness of the corrective action

In summary, use the tree diagram when:

• You and your team need to create an implementation plan for a complex project. (Note that the tree diagram can be time consuming and tedious, and may not be necessary for relatively simple projects.)
  
  
• The potential negative outcomes from missing a step are large (i.e., legal, safety-related steps or not meeting customer requirements).
  
  
• Your team has stalled at the implementation step and is confused about what to do next. The tree diagram provides a step-by-step process for creating an implementation plan.
  
  
• Your team is losing its focus. The tree diagram focuses your team on one main goal.
  
  
• There is a question about the sequence of tasks that need to be completed. Creating the tree diagram forces a team to think about and agree on the sequence of tasks for a project.
  
  
• Your team wants to check the logic of an implementation plan. A completed tree diagram will show potential gaps in a plan.
  

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