What action is primarily associated with the removal of specific trees to improve growing conditions for others?

The action that is primarily associated with the removal of specific trees to improve growing conditions for others is thinning. Thinning is a forest management practice where certain trees are selectively removed from a stand to reduce competition for resources such as sunlight, water, and nutrients among the remaining trees. This is particularly important in young or dense forests where overcrowding can hinder the growth of healthier and more vigorous trees. Thinning helps to promote better growth rates and can improve the overall health and resilience of the forest ecosystem.

Coppicing refers to a method of tree regeneration where trees are periodically cut down to ground level to encourage new shoots to grow from the stump, typically for timber production. Pruning involves the selective removal of branches from individual trees to enhance their structure and health, rather than focusing on the competitive dynamics of a whole stand. Harvesting involves the cutting down of trees for commercial purposes and does not specifically aim to enhance the growing conditions for remaining trees. Thus, thinning is specifically focused on improving the conditions for the residual forest, which is why it is the correct answer.