There is no question that the logistics of gathering wood as a power supply for fuel are challenging, and that biomass is bound to remain a small piece of the overall energy picture.
However, I am not suggesting to go after twigs/branches on the ground, dispersed over immensely large areas. Rather, it makes sense to use wood residuals only in places where you have a vibrant forestry industry with large industrial landowners (South-East and North-West). In those situations, you can access leftovers from harvesting operations at a reasonable cost ($3-4/MMBtu, including stumpage, loading, grinding, and hauling).That may still be too expensive for power generation, given the high capital and operating cost of a biopower facility, but, if you can use this fuel to replace more expensive petroleum-based products, it may start to be an acceptable cost.
In the South-East, where you have mostly pine plantations, you can get 10+ tons of wood residuals per acre harvested and there are also thinning operations that produce wood residuals. In the Northwest, where you have mostly douglas firs, you can actually get 30+ tons of wood residuals per acre harvested, but the topography may make it more expensive to extract. Closed loop (i.e. dedicated energy crops) is also a possibility, but that may be a little more expensive today ($4-6/MMBtu). There is also urban wood, trimmings, and material from wood processing facilties (chip mills, sawmills, and pulp mills).
I may write a separate piece on biomass supply chain economics, as it is an interesting topic.
Thank you again for your input