You are reporting the following comment to the PledgeBank team:
I want to congratulate Simon on his pledge.The idea is valid as woodlands store more carbon per unit area than other habitats e.g. grassland and therefore net effect is that carbon is removed from the atmosphere (as long as the forest exists and able to regenerate itself). I wanted to compare his numbers to mine. I planted a 12 Hectare plantation on my property. Using a value of 17kg/m2 (http://www.ilea.org/birdsey/carbon.html), at most 2000 additional tons of organic carbon will be stored by mature forest (in say 40 years time) consisting of about 3000 trees. That's an average of 50tC/year for 3000 trees. Average family emits 10tC/yr, so at very least 600 mature trees, planted now, are needed to offset emissions over a 40 year period for an average family. That' s consistent with simon's numbers (assuming he plants at least 10 trees every year from now on). Good news. The bad news is that we tried to offset everyone's C this way, we would run out of land.Joseph Wheatley, 13 years ago.