“Cloning” here seems the wrong (click-batey) choice of words. They have horticulturally propagated redwood trees - that’s a relatively simple technique, commonly used by your average gardener. What’s special here is that they found which conditions maximize the yield of the redwoods propagation and they are planting colonies of the new trees in areas around the world that offer particularly good/promising climatic co…
> As these are very large trees, establishing large colonies can have a relatively meaningful impact in carbon capture. Also, they're fast growing, so they capture carbon quickly, and store it for a long time. Plus the fact that, if they're harvested, the wood is relatively rot-resistant. So carbon could be stored over even longer periods, if the wood were used for ~permanent structures. Still, there's something iron…