A Bug Turns Up in U.S.-China Trade Relations
US says it will ban import of all Chinese goods shipped in raw wood packing material in effort to halt invasion of voracious Asian long-borned beetle; officials say wooden crates and pallets used to ship goods to North America sometimes harbor beetle, which has emerged from packing material after it arrives in warehouses to kill trees in five locations in New York and Chicago in last two years; ban is likely to result in delays or higher costs for a third to half of China's $62 billion in exports to US--at a time when China has already seen its export growth slowed by weak economies in other Asian countries; US Agriculture Sec Dan Glickman and Dr Isi A Siddiqui, Deputy Assistant Agriculture Sec, comment (M)