I thought this was a very neutral and comprehensive study. You have to be careful because a lot of pro-wood studies are funded by the wood industry lobbyist. I worked in an environmental consulting firm before and have seen both forestry areas and surface mines in Canada. The sheer scale of forestry is MASSIVE. So much land is required. Rock quarries (to get limestone or gravel for concrete) takes up a fraction of the land (more like a drop in a pool). You can get a 400m x 400m quarry which can be mined down in the z-axis, and that can easily have a life-span of 50+ years or even 100 years, and can serve the needs of a growing town of 300K+. You don’t just mine rocks from anywhere. To be economically feasible you only mine where there is significant depth of rock in the bedrock layers and it's close to the surface. They choose mining areas very methodically to minimize environmental impact. The heavy weight of rocks means it is always close to a population centre. At the end of quarry's life, the pit can be converted to a lake or a wetland to establish new habitat. A quarry has a small footprint, and can be located close to an urban area, and the site can be hooked up to grid electricity and run off clean electricity. You cannot do that with a forestry operation because it’s remote. You wouldn’t believe the number of heavy equipment they use and amount of diesel they burn. The soils are not the same after you go in with the heavy equipment, they are compacted. Nobody cuts trees manually with chainsaws anymore. To meet demand, they have to cut trees with heavy equipment and then use trucks to ship them out, which is very carbon intensive. This presentation also mentions the large amount of waste in lumber mills, and I can confirm that to be true. Wood is a natural material, it is imperfect, to get to the good parts for structural use, you will have a lot of offcuts. So, the actual lumber yield per kg of carbon input to extract the wood is very low. It is even worse these days because they forcing the trees to grow extremely fast, which actually degrades the quality of lumber and worsens the yield. I think in low quantities wood can be a good material to choose, but it is not realistic to scale it up to meet the growing population because it would just take too much land. Also, the carbon accounting methods currently used, which are endorsed by the wood industry, are very inaccurate and underestimates.

​@@UnbreakableM1nd This study was only about negative impact of wood - so, not comprehensive. You just gave more information about limestone than he did, that would have been more interesting to see. You mention that economically feasible mining will only happen where there is significant depth of rock - but viability depend on the price, which will increase if everyone starts building with limestone. And you mention the weight of limestone make it uneconomical to transport - so can only be used locally, so what do you do if you do not have limestone close to you? Responsible mining is a massive topic, not all countries have regulations that keep mining companies (or illegal mines) to best practices that reduces environmental impact or methodically minimize impact. You say it can be hooked up to the electricity grid, but that is also not necessarily clean energy? What if the local energy supply is from coal? Yes, some wood studies are are surely paid by Big Timber, same as some concrete studies being paid by Big Concrete, etc. I hope the authors would disclose that. But I am not paid by either - and I think if we want to have a serious debate, we need to look at every aspect of every material and standardize it somehow to compare. We also need to remember that demand for buildings are going to increase a lot, and it will be different everywhere in the world, so we need to take local contexts into consideration. You have experience with forestry, and understand their potential negative impact, but I live in a mining country, and I have seen what mines, quarries and even just mining sand can do to a landscape - so it is difficult for me to believe that limestone has so little impact.

@@AntoinetteVanDerMerwe-yv8gw I don't work on wood, I do work on concrete. Perhaps I'm biased. But regardless, just in terms of land usage, there isnt any comparison. The space needed for quarries for limestone and clay is indeed an absolute fraction of what it is for forestry. Yes, limestone has an impact, no doubt. But compared to almost every other material out there, it's pretty small. To fully replace concrete with wood, you would need to deforest half the world (or something similar). We can debate wood vs. concrete, that would be a separate talk (and perhaps we should have such a talk). It's absolutely true that concrete needs deep decarbonization, but it's also true that in terms of usage for construction, concrete does and will dominate wood. This is pretty comprehensive talk on wood, highlighting exactly why wood isnt really sustainable. Ultimately, using crazy amounts of concrete isnt really sustainable or environmentally friendly either, we really do need to use less and use wisely, but that is easier said than done.

How so?