That price is per tree planted and there's not guarantee the tree is going to grow. It's great to plant trees, but even if we could reforest the entire Earth on the good places we'll need other technologies to capture carbon.

Does the 0.10$ include land acquisition for the forest? If not, the cost could be significantly higher.

They work with the native communities (that is why around 10% of trees planted are designed as a food source) which allows that 10 cents to cover everything, not just the planting of the trees.

Reforestation only sequesters carbon if the land remains forest forever. If it’s cleared again in the future then that carbon goes right back into the atmosphere.

Doesn't it depend on what is done with all the wood that was chopped down? If used say for construction, that carbon is staying out of the atmosphere.

Or do mature trees not make up the majority of the carbon that is stored in forests?