fields attributes - Updating polygon areas in QGIS?

I'm using QGIS 2.6 and regularly update a shapefile layer to indicate felling progress. However, if I edit the nodes of a polygon, save the layer out then look at the Attributes table the area shown doesn't change.

Answer

You can create a Virtual field which updates features automatically based on the expression you insert. So in your case, it would be:

$area

You will need to create a Project for the shapefile (if you haven't done so already) as virtual fields are stored in the project files (.qgs).