Considerazioni sul cancro corticale del cipresso in Toscana con particolare riferimento alla bonifica fitosanitaria

Comments on cypress canker in Tuscany with a particular reference to sanitation Fifty years after its first report in Italy, cypress canker disease is still a serious threat for our cypress populations. In Tuscany, in spite of the large sanitation carried out in the past decades in cypress woods and ornamental populations, the incidence of the disease remains high (23 % on average), but observations carried out in nature and experimental results indicate that in the last 10-years period, the disease has been slowing down its spread. The most effective methods which have been used so far to control cypress canker are sanitation, chemical prevention and genetic improvement of cypress for resistance to cypress canker. The importance of chemical prophylaxis in the nursery is stressed; this will avoid the spread of the disease through the commercial sale of plants, which has occurred in the past. A hint is given at the success obtained by improvement programme of cypress: 4 resistant clones, suitable for ornamental purposes and to establish windbreak barriers, were selected and patented. The next goal to be reached is the large-scale production of seed with high percentage of canker resistant seedlings for reforestation. Sanitation is the only method to control the epidemic spread of the disease, its success depends on the immediate and detailed intervention and on the size of the area involved. A hint is given on the importance of organisational and legal aspects in order that sanitation can be extended into the entire countryside. The importance of surgical control to prevent deterioration of ornamental cypress populations is explained, but lasting benefit can be obtained only if care is taken to eliminate absolutely all sources of infection. The rules to observe in pruning are given and whether is better to prune or to cut down an infected cypress is explained. The experience in the Bolgheri monumental cypresses sanitation highlights the importance of operating by following rules imposed to the workforce by the seriousness of the disease and suggested by research.