Not just water spread. “The evidence indicates that P. ramorum spores can be spread over several miles in mists, air currents, watercourses and rainsplash. It can also be spread on footwear, dogs’ paws, tools, equipment, and bicycle and other vehicle wheels. Movement of infected plants is also a key means of spreading it over long distances.” (From FCS website).
My local forest has it. Was flagged a couple of weeks ago. Wood is coming out, much can still be used just as well because there’s some big trees. Smaller stuff is taken out to be pulped really small stuff chipped on site.
It will all be out by oct according to an email. There’s a lot of trees that can be effected including sikta. Large scale infestation would potentially cause real issues.