Well, in some very private and secluded yards where there is no risk of being seen by others, like a completely fenced - off and private property, it might be a personal choice within the couple's own boundaries. But still, it has to be in line with the local laws and regulations. In general society, we have a standard of appropriate dress in public or semi - public spaces like yards which are visible from outside to some extent.
I don't have information on who specifically created 'the basement yard fanfic'. There are so many fanfic writers out there, and without more context or research, it's impossible to know.
I'm not sure specifically as there could be many different 'fanfics' with this name. It might be about events that occur in a basement yard. Maybe it's a fictional story centered around the characters' experiences in that particular location.
No, it's not normal in most social and cultural contexts. In general, people are expected to be dressed appropriately even in their own yards as there could be neighbors, delivery people, or other unexpected onlookers. It goes against the norms of modesty and privacy.
To treat the yard for mange, it's important to mow the grass short and clear away any overgrown areas. Wash outdoor furniture and pet bedding regularly. You might also consider using natural remedies like neem oil or diatomaceous earth, which can be effective against mange mites without causing too much harm.