Why are you killing all the trees?
Though red and white pine trees have thick fire resistant bark, individual trees and groups of trees are often killed during prescribed fires. As unappealing as this is, the death of these trees is completely natural and absolutely necessary for the long term persistence of pine stands. Red and white pine stands naturally regenerate in openings created by intense fire. The adjacent live trees provide the seed for the new stand ensuring the persistence of the species on the site for another generation. Without the death of some over-story trees no regeneration can take place, and without regeneration pine will not persist on the site past the lifespan of the occupying cohort.
Couldn't the trees be better used for paper or lumber rather than allowing them to be burned?
Aside form the fact that commercial harvesting is illegal in National Parks and Wilderness Areas, the question of "best use" is somewhat a matter of opinion. As such, managers of public land attempt to accommodate all desired uses within the mission of their agency. From a scientific and aesthetic point of view, the preservation of areas that are "untouched" by man is desirable. From an ecological perspective, burned trees serve many purposes providing nesting habitat for birds and small mammals, shade for developing seedlings, and long-term storage of nutrients, which are released as the forest grows.