If you use drawtree or drawgram of the PHYLIP package and you want to
stick with the postscriptfile and have problems to "paste" it
into a graphics program like Illustrator or Freehand, convert it with
epsConverter (shareware on software servers) to an Illustrator format,
after that you can open the file with either Illustrator or Freehand
and add your length-bar or manipulate more (moving of labels etc.).
beerli at genetics.washington.edu