"Don't Interrupt, you know the squirrels are my friends/Get off my limb, I will break before I bend" announces Robert Pollard in "I Am A Tree", a Guided By Voices song that's almost 5 minutes long. This couplet can be read as a fragment of band biography: All of Pollard's recent collaborators have split, perhaps because of his inflexibility. Or it can be heard as another echo of the Dayton, Ohio singer-songwriter's previous career as a fourth grade teacher.

Except that this is the one song on Mag Earwhig! that Pollard didn't have a hand in writing. It's the work of guitarist Doug Gillard, formerly of Death of Samantha and currently of Cobre Verde, the Cleveland quartet that now serves as the hard-rock auxiliary to guided By Voices. With Cobre Verde behind him, Pollard rocks harder and longer - some of the time.

"I Am A Tree" is one of the album's two songs that breaks the four minute mark; two others don't make it to 40 seconds. Pollard still crafts pithy pop rockers such as "Bulldog Skin", which is twangily exuberant, and "Jane of the Waking Universe", which sounds like the Hollies reimagined as a conceptual-art project. He also fashions such offhand fragments as "The Old Grunt", a simple-strummed ditty on which his faux-Brit accent resembles John Cale's. As always, some of these songs call for a little more consideration; "I Am Produced" would be more satisfying if it went someplace else than into a quick fade at 1:07. Pollard has to be careful, though. Now that he has a professional rock band backing him, only his cut-up songcraft stands between him and the Offspring's fan base.