procedure(wmExpandDescendants(_field itemSym)
          let((trees childItems)
                  ;Recursive expand
                  hiExpandTreeItem(itemSym nil) 
                  trees = hiGetTree(eval(itemSym)) ; Note eval
  
                  ;Possibly warrants a seperate forum post, but hiGetTree sometimes returns a list? Which according to docs should be s_treeName/nil
                  foreach(childTree if(listp(trees) then trees else list(trees))
                          childItems = hiGetTreeItems(eval(childTree)) ; Note eval
                          foreach(child childItems
                                  wmExpandDescendants(nil child) ; recursive call
                          )    
                  )    
                  t    
          )    
  )