I would have to say that it's the health and well-being of the elements that's the most critical. We often discuss trees in a hypothetical sense, forgetting that they are unique individuals within their species specificity. In addition, there is more to a tree than what's above the ground. You can't have the ecosystem services benefits that are touted if the landscape underground is not addressed. In other words, you can't have top without bottom. This is a problem that has not been resolved and although we are planting trees, we are not growing them because we have not addressed the complete inadequacy of an adequate, accessible soil volume and that's not even discussing the soil quality. Until we do that, the 2 primary carbon sinks - soil and trees - are not delivering what we need them to deliver.