This article appeared in The Economist and sums up the need and benefit of thinning the forests of the Sierra Nevada. I’ve added a few comments about it below.
I really appreciate the discussion regarding water generation through thinning. I believe this is one of the least discussed benefits of practicing forestry in the West, but in California it’s one of the biggest benefits with our constant water deficits. Thinning the Sierra forests would generate an enormous amount of water for California.
When comparing the cost of controlled burning to mechanized thinning (logging) you can’t ignored the cost incurred when controlled burns get out of control. The cost differences between doing controlled burn and fighting out of control fire is enormous. I’m not saying don’t use controlled burning, but fire suppression costs need to be included when controlled burns get out of control. Controlled burning is one tool available, but cannot come close to solving the problem of all the overstock forests.
Commercial thinning that includes merchantable (larger) trees is the only economically sustainable way to accomplish the massive level of thinning that needs to be done. The author points out 52 trees per acre was the historic density of trees in the Sierra. Research has shown that the proper density for optimal growth in fully stock mature timber stands to be between 43 and 64 trees per acre depending on the size of the trees. If we remove 236 trees per acre to reach 64 trees per acre, then some of those trees have to be big enough to make a 2 x 4. If there is enough value in the larger trees, a timber company will pay the federal government to thin the forest instead of the government paying a contractor to clean up and dispose of the unmerchantable trees.
What’s the upside? We get healthy resilient forests that are more fire resistant. Wildfires that do start are less severe, and safer and easier to control. There is more water available to the state. The wood isn’t left to rot. It is used in wood products and to generate electricity. People doing these forest related jobs see an economic benefit, particularly in the rural communities. The practice is sustainable and wood is our great renewable resource.
Lastly, some folks are going to fret over the impacts of logging at that scale. I want you to know this, timber harvests are studiously planned to mitigate the potential negative impacts they could cause. Secondly, just imagine the negative effects of these mega-fires. I’ve seen them and their effects are staggering. I’ve yet to see one large burn ever have it’s negative impacts fully mitigated.