Hi, Artful Codger-
Look at the grange songbooks linked to above, and you'll find temperance songs. Google temperance grange, and you'll find lots of stuff - click here for an example. In the U.S. Midwest where I'm from, it was only the Catholic farmers who drank, and you won't find much of a connection between the Catholics and the Grange.

Now, I may be wrong, but my hunch is that the DT's connection between this song and the Grange, is a bunch of serious hooey.

Let union be in all our farms,
Let all our farms be joined as one.

That's gotta be somebody's joke.....

-Doubting Joseph-