The oak tree pathogen Phytophthora ramorum has migrated 650 km in ten years. West Nile virus spread from New York State to 46 others states in five…

The oak tree pathogen Phytophthora ramorum has migrated 650 km in ten years. West Nile virus spread from New York State to 46 others states in five years. The difference in the rate of spread is probably related to