ðə wˈɛstɚn pˈɑːɹt ʌvðə hˈɪlz wˈʌns hæd ɛkstˈɛnsɪv ˈoʊld ɡɹˈoʊθ fˈɔːɹɪsts, bˌʌt ɪnðə wˈʌn θˈaʊzənd ˈeɪthˈʌndɹɪd z ðeɪ wɜːɹ ɐ sˈoːɹs ʌv tˈɪmbɚ fɚðə sˌæn fɹænsˈɪskoʊ bˈeɪ ˈɛɹiə, ænd ðˈʌs lˈɔɡɪŋ tˈʊk ˈaʊt mˈoʊst əv ðɪ ˈoʊld ɡɹˈoʊθ stˈændz; haʊˈɛvɚ, wˈʌn ˈoʊld ɡɹˈoʊθ stˈænd ɹᵻmˈeɪnd ʌŋkˈʌt ɪn sˈɛkwɔɪə kˈænɪən, dˈuː tə ðə stˈiːp tɚɹˈeɪn ænd ɪt ðˈɛɹfoːɹ wɪðstˈʊd pɹˈɛʃɚ fɹʌm lˈɔɡɚz ænd wˈɔːɾɚ kˈʌmpəniz.
The western part of the hills once had extensive old growth forests, but in the 1800s they were a source of timber for the San Francisco Bay Area, and thus logging took out most of the old growth stands; however, one old growth stand remained uncut in Sequoia Canyon, due to the steep terrain and it therefore withstood pressure from loggers and water companies.