Guidelines on when strokes are needed on maps

[Alice Feng]

Need to clarify when map entities (e.g. states, counties, census tracts) should have strokes and when they should not.

Tentative thoughts:

• States: should always have an outline (in white, 1pt thickness)
• Counties: it depends. If it's important to identify individual counties then there should be a stroke. If counties are only being used to display smaller geographic areas then they do not need strokes.
  • In maps where the largest geographic area being displayed is a state, individual counties should be outlined.
• Smaller geographic units (e.g. census tracts): generally do not need to be outlined as this makes it difficult to visually interpret what is being displayed.

However, any of these guidelines can be overridden depending on the circumstances. Bottom line: it's a judgment call!