In addition to what thundergnat has shown, you can make the scrollbars appear 'O'nly when you need them with the 'o' notation.

#!/usr/bin/perl
use warnings;
use strict;
use Tk;
use Tk::Pane;

my $top = MainWindow->new;
$top->geometry("150x300");

my $pane = $top->Scrolled('Pane',
-scrollbars => 'oe',    #   'osoe'  for both bars
)->pack(-expand => 'y', -fill => 'both');

for (0 .. 5)
{
$pane->Button(
-text => $_,
-width => 15,
-command => [sub{print "Button $_[0] Pressed\n"},$_],
)->pack;
}

$top->Button(
-text => 'Quit',
-command => sub{$top->destroy},
)->pack;

MainLoop;
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