Two nominees come to mind:

The Farmer Is The Man is one. There are two references earlier in this thread that just might be referring to this song.

and

We're Up Against it Now This is a song, I think from about 1918 or so, bewailing what automobiles, trucks, and tractors--in sum, the internal combustion engine--has done to farming economics. I'll give two verses and the chorus:

Since the aut-to's come
Mules and horses won't sell
The farmer's land is mortgaged down
And the country's gone to hell!

Cho: We're up against it now
There's no need to raise a row
Of all the times I've ever seen
We're sure up against it now!

A farmer bought him a tractor
It raised quite an alarm
He only broke one little piece
And he had to sell his farm!

Cho. We're up against it now etc.

I think this was written by Uncle Dave Macon.

Dave Oesterreich