Barn Red

I came to wonder why most U.S. barns are painted red.
It started with the colonists (as several sources said),
Who gave their barns priority for sealing from the weather.
They typically mixed linseed oil, lime, and milk together.
That mixture would be orange, so they must have added more.
Some posit blood of livestock that was slaughtered just before,
But that seems rather wasteful, so more likely, it was rust.
Not only was the ferrous oxide common as the dust;
It countered moss and fungi and prevented wood decay.
Perhaps red paint stayed cheaper than the rest in later days,
Until the dawn of whitewash, which took up the red’s position.
Today, red barns prevail again for nothing but tradition.