European plant health requirements for forest pests1

The publication of lists of quarantine organisms by EPPO in 1975 and of the EC Council Directive on Plant Health in 1977 were major milestones in the establishment of plant health requirements in Europe. The substantial risks to European forest trees from alien pests were recognized and most European countries now prohibit the importation of trees of important forest genera into Europe from other continents. There is a need to establish and up-date lists of potentially dangerous forest pests in order that appropriate preventive measures can be introduced. However it is important to recognize that lists of potentially dangerous organisms can never be complete. In effect this is recognized by the provisions of the EC Directive but not so far in the EPPO Lists of Organisms and related Specific Quarantine Requirements. Examples of host-oriented plant health requirements, such as those associated with coniferous wood, will be discussed.     

A Study of Losses in Scots Pine caused by Fomes annosus

Data are presented from unreplicated Scots pine {Pinus sylvestrisL.) sample plots in Thetford Forest which have been differentiallyattacked by Fomes annosus (Fr.) Cooke. Volume production ofseverely infested crops differs markedly from that forecastby management tables. The volume of dead trees may not representthe total loss of volume in these plots as there appears alsoto be a reduction in the growth of the remaining live trees.These observations may have considerable significance in forecastingfuture volume production from stands attacked by F. annosusand also in deciding the optimum time for their replacement.