The outbreak map identifies areas where there is or has been confirmed or presumed* infection in larch trees. The blue dots indicate larch woodland sites where P. ramorum infection was confirmed or presumed and statutory plant health notices (SPHNs) were issued before April 2011; the red dots indicate sites where infection by P. ramorum was confirmed or presumed and SPHNs were issued in 2011; and the green dots indicate infection sites confirmed or presumed and SPHNs issued in 2012.
* (Laboratory analysis of samples returns conclusive results in only a minority of cases, so a presumption of infection is used where all the other indications point to the presence of P. ramorum infection.)
The risk zones map identifies the three zones into which the UK has been divided according to the risk of P. ramorum infection. It shows how, on the basis of scientific advice, the UK has been divided into three risk zones, with Zone 1 being at greatest risk from P. ramorum infection, and Zone 3 being at least risk.
Different regulations governing felling and replanting trees apply according to the risk zone in which the site is located.