Django Problem with -n 1

When I run pytest with xdist, I get an error that I don't get if I run the same exact command but without the -n 1 flag. Any number of processors specified is sufficient to generate the error.

django.core.exceptions.ImproperlyConfigured: Requested setting LOGGING_CONFIG, but settings are not configured. You must either define the environment variable DJANGO_SETTINGS_MODULE or call settings.configure() before accessing settings.

Do I need to do something special to avoid this? When I had this problem previously, it seemed to fix the issue when I put:

[pytest]
addopts = -p no:django

in my pytest.ini. But the problem has come back now. I tried upgrading pytest-django, but it is the same error essentially:

django.core.exceptions.ImproperlyConfigured: Requested settings, but settings are not configured. You must either define the environment variable DJANGO_SETTINGS_MODULE or call settings.configure() before accessing settings.

pytest (3.9.1)
pytest-cov (2.6.0)
pytest-django (3.4.3)
pytest-forked (0.2)
pytest-mock (1.6.3)
pytest-sugar (0.9.1)
pytest-watch (4.2.0)
pytest-xdist (1.23.2)

I understand that I can set DJANGO_SETTINGS_MODULE, but why do I need to? The tests I'm running do not import django at all and if I don't use xdist, then this isn't an issue.

Start by reproducing the reported pytest run with xdist and -n 1, comparing it with the same run without xdist. Inspect how pytest-django and pytest-xdist interact with pytest.ini, DJANGO_SETTINGS_MODULE, and the disabled django plugin. Done means the cause is identified and the failing configuration no longer raises Django's settings error.