Actually known as Asian Giant Hornets, Vespa japonica or Vespa mandarina, no one really knows how long they have been in the country. I have read the reports made by the Washington Department of Agriculture which has been tracking this creature for the last year. Sighted in the state of Washington, the Washington Department of Agriculture has recorded two verified sightings and two unverified sighting. They can grow to up to two inches in length and have a nasty stinger which is seven times as venomous as the bee. They don't do well with cold winters however, which will probably limit their size and number. The Washington Department of Agriculture has put out traps in four counties to catch and monitor these insects. It is unlikely that you will see them but if you do, my advice is to run first and ask questions later. Make a report to the Department of Agriculture in the state in which you make the observation, in the very unlikely event that you see one.