The United States and Canadian governments are mounting a defence against Russian invasion. No, the clock has not been turned back. These invaders are Asian gypsy months, foliage-chomping insects that can cause billions of dollars in damage. Experts believe they entered North America from Russia last year in egg masses attached to grain vessels. The larger Asian gypsy moth is more voracious feeder than the common North American strain and can feed on pacific northwest tree species. Unlike the flightless North American female, an Asian female can fly 20 miles between mating and egg -laying. The United States Health Inspection Service is barring from west coast ports ships found carrying egg masses. The Tacoma and Portland areas, as well as Vancouver. British Columbia has been sprayed with a bio-pesticide.