Border-Width
This property allows you to set or retrieve the width of the four borders of the Tree-View control. The property is a list of four values that specify the width in pixels of the top, left, bottom and right border respectively. The border width is applicable only to controls with the Boxed style.
 
Example - Define a tree-view control with a huge bottom border
screen section.
...
  03 screen-1-ef-2 Tree-View
     line 35.5
     column 49.7
     size 13.1 cells 
     lines 4.6 cells 
     border-width (1 1 5 1)
     id 19
     3-d
     .