"Earth Tones" is a cool laid back groove at 92 bpm with an F# Dorian progression that lends itself to shimmering tremolo guitar and nice sustained parts. I kept the B7sus chord unresolved as I felt it kept the progression interesting. The passing chords of A and E/G# bass add punch and accent on the turnaround.
In Roman numerals this progression constitutes a II - V - IV - I - II progression in the key of E. When soloing, use the F# Dorian mode and phrase it smoothly with a slinky feel. F#mi Pentatonic and C#mi Pentatonic will take you there too!