[Zope-dev] Does anyone know how to suppress display of +/- signs on a dtml-tree?

Hello: I want to display a dtml-tree always expanded, with no controls visible for contracting (basically, an indented list of links). I set the tree to always expand via the following: <dtml-call expr="REQUEST.set('expand_all', 1)"> <dtml-tree single=0 name="catalog" branches="objectValues"> But I can't figure out how to remove the little minus signs (-) from the branches. Has anyone done this? TIA, --Craeg