When the American composer Charles Ives composed his trio, he was in his late twenties, early thirties. We actually don’t know, because much of his music was published much later. He put his music in a drawer and went on with his professional life: he was in insurances, not in music. It took until 1948 before it was first performed.
The simple explanation for that is that his music was lightyears ahead of its time. People didn’t understand it. Another explanation might be that he just wasn’t very good at selling himself. Yet another that his handwriting is not easily read: he made a mess of his sheet music. All of that led to that premiere of the work in New York, accompanied by the 74 years old composer. It is said he wept when he heard it.
The middle part is the most interesting: it is a musical collage of sorts, filled with popular American tunes, following and superimposed on each other. Ives was able to do this: he could made different melodies blend into each other at the same moment. The collage is meant as a memory of his student times around the turn of the century at Yale.