First, there are some changes in the third verse that reflect the "liberty" that's mentioned in the lyrics. The first two verses have AABB rhyme schemes:
Have you ever been south of Monterey; Barrancas carve the coast lineAnd the chaparral flows to the sea 'neath waves of golden sunshineAnd have you ever been north of Morro Bay; the south coast plows the seaAnd the people there are of the breed that don't need electricity
Have you ever been down Salinas way, where Steinbeck found the valleyAnd he wrote about it the way it was in his travelin's with Charley*And have you ever walked down through the sycamores, where the farmhouse used to beThere the monarch's autumn journey ends on a wind-swept cypress tree
but the third verse exhibits more internal rhyme than line-ending rhyme:
Have you ever been to a festival, the Big Sur congregationWhere Country Joe will do his show, and he'd sing about libertyAnd the people there in the open air are one big familyYeah, the people there love to sing and share their newfound liberty
The third verse is different musically, too. The second half alternates between F# major and B major where the other verses have the progression B major | E major | F# major | B major (a repetition of the first half of the verse).
In both the poetic and musical structures, the third verse breaks from what comes before it, and this illustrates that "liberty."
Second, there are a number of elements that are reminiscent of "California Girls." Obviously, California is in the title and lyrics of both songs, but there are also specific musical elements that the two songs have in common. Both are in B major, and the bass parts for the verses use the same root, fifth, sixth, fifth figure.
The bass part in the verses of "California Girls" is something like:
and the bass part in the verses of "California Saga: California" is something like:
(The actual parts are looser than what I've indicated; the note values shouldn't be observed too precisely.)
The same figure (root, fifth, sixth, fifth) is used throughout both parts, and the chord progressions are similar but not exactly the same. Above some of the B F# G# F# figures in "California Girls" (measures three, four, eleven, and twelve) there are A majors instead of B majors, but otherwise, the first note in each bass figure corresponds to the root note of the chord, so the majority of the chord progressions consists of B major, E major, and F# major.
Because the musical similarities are so close, I think this resemblance was intentional and meant as a nod to "California Girls."
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*In the CD booklet of my copy of Holland, it's spelt "Charlie," but the Steinbeck book that's alluded to is Travels with Charley.