Nickel Creek's mandolin virtuoso Chris Thile knows bluegrass from the inside out, and he never forgets where its heart is when he ventures beyond its borders for inspiration. How to Grow a Woman from the Ground, another exciting solo journey on which Thile is joined by a solid quartet of guitar, bass, banjo, and fiddle on a patchwork quilt of songs from various sources (including his own raw-nerve originals about love and loss) that he and his mates translate into bluegrass terms. These sources range from the legendary Spanish Celtic band Milladoira (whose lively instrumental, "O Santo de Polvora," is a moment of pure joy, an irresistible Irish reel full of exuberant, life-affirming dialogue between the fiddle and banjo) to Jack White's up-tempo, slightly skewed explication of a relationship gone sour in the driving, bluesy "Dead Leaves and the Dirty Ground" to a bustling, fiddle-fired workout on Jimmie Rodgers's classic "Brakeman's Blues." The Strokes' "Heart in a Cage" gets countrified and even gospelized in these capable hands, it's one of the album's most vivid moments. But Thile's own songs stand out for their raw intimacy, their breathtaking flights of instrumental musings, and, especially on the desultory, spare "I'm Yours if You Want Me," for the artist's willingness to put the load right on himself. Love may not have been good to him of late, but Thile knows he'll find a soothing balm in the music he was raised on.