Random tree planting without proper consideration to the nature of the environment and consequences of the tree planting can and has led to issues, from lack of biodiversity in the environment to altering the existing environment, for example tree planting has detrimental effects associated with peat bog environments.
As with most things there is a balance to be struck, trees have tremendous potential to act as a carbon sink, a place to store the excess carbon that human activity has pumped into the atmosphere since the start of the industrial revolution. However, trees are also dark compared to other things blanket the land. As a result, planting more trees typically makes the land darker. Since dark surfaces absorb more heat, a dark tree-covered surface will trap more of the Sun’s heat – and warm the local climate.
As a result, there is a delicate balance between trees’ ability to take in CO2, reducing warming, and their tendency to trap additional heat and thus create warming. This means planting trees only helps stop climate change in certain places.
Specifically, according to a 2007 study that has been repeatedly confirmed,the best place to plant new trees is the tropics, where trees grow fastest and thus trap the most CO2. In contrast, planting trees in snowy regions near the poles is likely to cause net warming,
As always sweeping statements rarely reflect the true nature of things. Tree planting can help if conducted appropriately and in the right places, also let’s not forget that in many places we are replanting trees that used to be there before human activity destroyed them.