If you are running some django tests in an environment where you want to force south to run, you can use this gist. This was taken from the pycharm test runner.

enable_south_migrations.py

from django.core import management
from django.conf import settings


def enable_south_migrations():
  management.get_commands()
  if hasattr(settings, "SOUTH_TESTS_MIGRATE") and not settings.SOUTH_TESTS_MIGRATE:
    # point at the core syncdb command when creating tests
    # tests should always be up to date with the most recent model structure
    management._commands['syncdb'] = 'django.core'
  elif 'south' in settings.INSTALLED_APPS:
    try:
      from south.management.commands import MigrateAndSyncCommand

      management._commands['syncdb'] = MigrateAndSyncCommand()
      from south.hacks import hacks

      if hasattr(hacks, "patch_flush_during_test_db_creation"):
        hacks.patch_flush_during_test_db_creation()
    except ImportError:
      management._commands['syncdb'] = 'django.core'