New Zealand is known for its natural beauty, and it has a fiercely protective environmental movement to match. But that didn't stop a forestry planner for a U.S. company from standing on a hill, looking down over a majestic pine forest and cheerly talking of mowing it down as far as the eye can see. The doomed trees were about to join hundreds of other hectares of pines that Weyerhaeuser has recently felled as part of a cutting regimen more intense than anything it does in the U.S. But the harvest has aroused none of the antilogging passions that the forest-products giant come to expect back home.