If we want to sequester carbon one of the best things we could do would be to clear cut all the old growth forest and use the wood in some type of permanent structures. Replace the old trees with fast growing species that pull a bunch of CO2 out of the atmosphere. This solution rarely gets discussed because it sucks. All outdoors enthusiasts would ideally be united in the goal of preserving habitat and limiting development--instead we fight each other. If we want to take the thread way off target we could discuss the morality of using fossil fuels for recreation. Is it ok to use the most precious commodity we have just for fun? All of our food and the distribution of food depends on a finite resource. Are we fools? Future generations may judge us harshly, but on a perfect day in the mountains riding this is the last thing on my mind.