The main use of modes in this book is to combine them with chords. When individual scales are analyzed, theirinterval patterns describe exactly which chords can be played with them (above). In a specific key, modes describe exactly which chords can be played with each note. Any combination of triad and add can be made with each mode while still remaining within the limits of the scale being played. This is an invaluable tool, as it gives us the options to work with when playing within a scale and allows us to explore chords we might not normally use.
Knowing how modes work to give us chords, it is possible to scan the scales as diagrammed on the fretboard and see some of the chords that can be played. Understanding the position of the bass note to the harmonic (in chords) is crucial to gaining this ability. To do this, use the chord encyclopedia to learn where the harmonic notes are in relation to bass notes in regular and negative chords. With some practice, you should be able to see many of the chords within the scale without having to use the reference charts. This will allow you to explore scales more efficiently than having to constantly look up this information.