Why Is Pearl Jam Planting All Those Trees?

Pearl Jam somehow calculated the carbon footprint of the band's current world tour, and the trees will help offset the environmental damage of their road show.

According to the Seattle Times:

• The band's 14 trucks, six buses and other shipments rack up some 1,600 metric tons of emissions.
• The band and crew travel 899,525 passenger miles, creating another 1,182 metric tons of carbon.
• Hotel rooms add up to 3,183 nights for band and crew, and cost 114 metric tons of carbon.
• The 32 venues use 484,800 kilowatt hours of electricity, or 187 metric tons of carbon.

So, how many trees will they need to plant?  33 acres, spread out around Washington state.