As far as green musicians go, the Dave Matthews Band and Pearl Jam are up there.

According to Billboard, they're No. 4 and No. 6, matter of fact.

Billboard says, "The Top 10 green musician activists from the past year were chosen by overall positive impact on the environment; the extent to which the artist integrates a green approach into all aspects of his/her career; perceived sacrifice of choices; and trailblazing nature/originality of ideas."

In order, from first place, Billboard's picks are Jack Johnson, Willie Nelson, Mana, Dave Matthews Band, K.T. Tunstall, Pearl Jam, Serj Tankian, Radiohead, Missy Higgins and The Roots.

Dave Matthews and company received props for their summer plans: using biodiesel for fueling their tour buses and trucks and eating organic and local food backstage. They've also calculated the carbon dioxide emissions from that upcoming tour and purchased renewable energy credits through NativeEnergy.

Pearl Jam's claim to green fame sprouts from $120,000 in donations to organizations dedicated to climate change and renewable energy. They also received kudos for a benefit they threw to aid flood victims recently devastated in Centralia and for taking steps to reduce their carbon footprint in upcoming concerts.

Also included in the issue are stories on the touring industry (from green merch to green venues), green instruments, green festivals and much more.

It's on newsstands this week. Here's an online preview. And here's the PDF. Billboard magazine's Green Issue, March 2008