How to check where in a menu tree a node is & then display a portion of the tree? How can I check where in a menu tree a node is, and in particular how can I determine what its ultimate parent is? And how can I display a portion of a menu tree? Here's an example menu tree to illustrate:

m1
-subm2
--subsubm3
-subm4
m5
-subm6


If I were on the pages linked to from items 1-4, I'd want to find out that the ultimate parent of these items is m1, and then display only the portion of the menu below m1, ie:

m1
-subm2
--subsubm3
-subm4
I am pretty sure Menu Block will do what you need. I have used this module to display portions of menus only under one parent item as you mention and it worked great. It's for Drupal 6 &amp; 7 as well.