The acoustic guitar is one of the six stringed instruments associated with bluegrass music. In contemporary bluegrass music, it is most often played with a single plecturm, in a style referred to as flatpicking. The style of guitar most associated with bluegrass is the dreadnaught, most famously those manufacted by C.F. Martin & Co.
Initially the guitar was almost exclusively used as a rhythm instrument, but innovators such as Clarene White and Doct Watson built upon a hybrid picking style used by Maybelle Carter.
In the 1970s and 1980s Tony Rice expanded the scope of bluegrass guitar with his jazz-influenced harmonic variations.