I assume you are American? Brit here. I can't speak for every dialect, but mine uses 'earth' to refer to the thing that plants grow in. 'Dirt' is seldom used. Rather, we use 'mud'.
He's Canadian, actually, Jakv6. Prince William Island. We use earth in the U.S. and also soil. Dirt tends to be relegated to a negative context here. Dirty clothes, dirty thoughts, etc.
I would have said that in the US we use soil or dirt, and hardly ever use earth with this meaning. Looks like we're running into the issue of the US having a bazillion dialects. Edited to add, from Tremors: Rhonda: "See, they move very easily through the Pleistocene alluvials." Everyone Else: (Blank stare) Rhonda: "The dirt. The loose soil that covers the valley floor."
Interesting you should say this because I decided to keep the word, sun, (small s), for the star in the new solar system, Centauri. Even though our sun is called the Sun, the word is used for other stars in many references. Centauri-rise wasn't practical, too many syllables. It didn't seem likely people would use that term to replace the word, sunrise.
