Category :
                    
                    Article
                                    
                            
                    
        
            
            article id 5611,
                            category
                        Article
                    
        
        
                            Arja Lilja,
                            Timo Kurkela,
                            Sakari Lilja,
                            Risto Rikala..
                    
                    
                (1997).
            
                            
                                    Nursery practices and management of fungal diseases in forest nurseries in Finland. A review.
                            
                            
                Silva Fennica
                                                            vol.
                                        31
                                                                            no.
                                        1
                                article id 5611.
            
                            
                https://doi.org/10.14214/sf.a8512
            
             
        
                                    
                                    
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                            The purpose of this article was to collate the literature on fungal diseases that occur on seedlings in forest nurseries. It describes the symptoms of the diseases, the infection pattern of each fungus and the possibilities of controlling the diseases. As background a short introduction is given on forests and nursery practices in Finland.
                
                                            - 
                            Lilja,
                            
                                                        E-mail:
                                                            al@mm.unknown
                                                                                          
- 
                            Kurkela,
                            
                                                        E-mail:
                                                            tk@mm.unknown
                                                                                
- 
                            Lilja,
                            
                                                        E-mail:
                                                            sl@mm.unknown
                                                                                
- 
                            Rikala.,
                            
                                                        E-mail:
                                                            rr@mm.unknown
                                                                                
 
         
     
 
                        
                
                
                                            Category :
                    
                    Article
                                    
                            
                    
        
            
            article id 7612,
                            category
                        Article
                    
        
        
                            Timo Kurkela.
                    
                    
                (1969).
            
                            
                                    Antagonism of healthy and diseased Ericaceous plants to snow blight on Scots pine.
                            
                            
                Acta Forestalia Fennica
                                                                            no.
                                        101
                                article id 7612.
            
                            
                https://doi.org/10.14214/aff.7612
            
             
        
                                    
                                    
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                            Two experiments were conducted in Punkaharju and Leivonmäki in the Central Finland in 1966-67 where the spread of the snow blight caused by Phacidium infestans Karst. was investigated in rows of excised branches from a ten-year-old stand of Scots pine (Pinus sylvestris L.). Ericaceous plants (Calluna vulgaris (L.) Hull and Vaccinium vitis-idaea L.) infected with snow moulds were used to determine their influence on the spread of snow blight.
The results show that significant inhibition of snow blight in Scots pine can be achieved with foliage of ericaceous evergreens. The mechanism of this inhibition is an object of conjecture. In healthy ericaceous vegetation it might be caused by saprophytic fungi living on surface of plants or by some constituent of the foliage. In the case of dead ericaceous foliage, the cause of inhibition seems to be the antagonism of other snow moulds. The antagonism of certain saprophytic organism is well known.
The observed inhibition suggests that ericaceous vegetation may be helpful for reforestation by offering a natural control of snow blight, when seedlings of Scots pine do not stand above the surrounding vegetation.
The PDF includes a summary in Finnish.
                
                                            - 
                            Kurkela,
                            
                                                        E-mail:
                                                            tk@mm.unknown
                                                                                          
 
         
     
 
                        
                
                
                                            Category :
                    
                    Research article
                                    
                            
                    
        
            
            article id 360,
                            category
                        Research article
                    
        
        
                            Timo Kurkela,
                            Tarmo Aalto,
                            Martti Varama,
                            Risto Jalkanen.
                    
                    
                (2005).
            
                            
                                    Defoliation by the common pine sawfly (Diprion pini) and subsequent growth reduction in Scots pine: a retrospective approach.
                            
                            
                Silva Fennica
                                                            vol.
                                        39
                                                                            no.
                                        4
                                article id 360.
            
                            
                https://doi.org/10.14214/sf.360
            
             
        
                                    
                                    
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                            The foliage status in the main stem of Scots pines (Pinus sylvestris)  was studied retrospectively using the needle trace method (NTM) on a  stand, seriously defoliated by the pine sawfly (Diprion pini) in the  1980s. Needle density increased abruptly in the seasons following the  defoliation. The strongest reduction in annual needle production  occurred one year later. As a consequence of lower needle production,  the annual number of attached needles decreased three to five years  after the defoliation. Needle retention and the average age of attached  needles tended to increase after defoliation. In analyses of covariance  with the NTM variables, needle density (logarithmic transformed values)  and average age of attached needles, had the highest, significant,  negative relationship with radial and height increments both in the  period prior to the defoliation and in the time when the trees were  suffering from defoliation. The relationships between height increment  and the number of needles and needle loss were positive and significant.  Also radial increment had a positive relationship with the number of  needles but not with needle loss. Interestingly, an abrupt increase in  the needle density gave a good indication of the effects of a sudden  defoliation in pines.
                        
                
                                            - 
                            Kurkela,
                            Finnish Forest Research Institute, Vantaa Research Unit, P.O. Box 18, FI-01301 Vantaa, Finland
                                                        E-mail:
                                                            timo.kurkela@metla.fi
                                                                                          
- 
                            Aalto,
                            Finnish Forest Research Institute, Rovaniemi Research Unit, P.O. Box 16, FI-96301 Rovaniemi, Finland
                                                        E-mail:
                                                            ta@nn.fi
                                                                                
- 
                            Varama,
                            Finnish Forest Research Institute, Vantaa Research Unit, P.O. Box 18, FI-01301 Vantaa, Finland
                                                        E-mail:
                                                            mv@nn.fi
                                                                                
- 
                            Jalkanen,
                            Finnish Forest Research Institute, Rovaniemi Research Unit, P.O. Box 16, FI-96301 Rovaniemi, Finland
                                                        E-mail:
                                                            rj@nn.fi
                                                                                
 
         
     
 
            
        
            
            article id 537,
                            category
                        Research article
                    
        
        
                            Timo Kurkela.
                    
                    
                (2002).
            
                            
                                    Crown condition as an indicator of the incidence of root rot caused by Heterobasidion annosum in Scots pine stands.
                            
                            
                Silva Fennica
                                                            vol.
                                        36
                                                                            no.
                                        2
                                article id 537.
            
                            
                https://doi.org/10.14214/sf.537
            
             
        
                                    
                                    
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                            Trees in three Scots pine stands seriously infected by Heterobasidion  annosum were classified according to their crown condition into four  classes, from healthy to dead trees. After cutting the stands, the  classification was compared with the symptoms of annosum root rot on  stump surfaces (pitched area) and with the extension of decay in the  roots of excavated stumps. When dead trees were included, the average  crown condition on the survey plots correlated with disease incidence.  Without dead trees the correlation was not significant. Slightly  infected trees could not be distinguished from healthy trees on the  basis of crown condition. It was concluded that only the proportion of  dead and dying trees in a stand is a reliable indication of the disease  incidence for making decisions about the future management.
                        
                
                                            - 
                            Kurkela,
                            Finnish Forest Research Institute, P.O. Box 18, FIN-01301 Vantaa, Finland
                                                        E-mail:
                                                            timo.kurkela@metla.fi
                                                                                          
 
         
     
 
                        
                
                
                                            Category :
                    
                    Review article
                                    
                            
                    
        
            
            article id 147,
                            category
                        Review article
                    
        
        
                                    
                                    
                            Abstract |
                        
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                            Norway spruce (Picea abies), Scots pine (Pinus sylvestris) and silver  birch (Betula pendula) are the major tree species grown in Finnish  forest nurseries where 99% of the seedlings are grown in containers  first in plastic-covered greenhouses and later outdoors. The main  diseases on conifer seedlings are Scleroderris canker (Gremmeniella  abietina), Sirococcus blight and cankers (Sirococcus conigenum), snow  blights (Herpotrichia juniperi and Phacidium infestans) and needle casts  (Lophodermium seditiosum and Meria laricis). Also grey mould (Botrytis  cinerea) and birch rust (Melampsoridium betulinum) are among the  diseases to be controlled with fungicides. During last years  Scleroderris canker has been a problem on Norway spruce, which has been  since 2000 the most common species produced in Finnish nurseries. Root  die-back (uninucleate Rhizoctonia sp.) on container-grown spruce and  pine was a problem in the 1990s. Today the disease has become less  common in modern nurseries due to improvements in hygiene and  cultivation practice. Since 1991 stem lesions and top dying caused by  Phytophthora cactorum has been a problem on birch. The ongoing climate  change has already had effect on rusts and powdery mildews as well as  other fungi infecting leaves. All diseases, which gain high  precipitation and warm and long autumns. For same reasons winter stored  seedlings need sprayings against grey mold. Fungal infections are also  possible during short-day (SD) treatment, that is necessary for summer  and autumn plantings and a beneficial step prior freezing temperatures  outside or in freezer storage. Growers are encouraged to use cultural  and integrated pest management techniques such as better nursery  hygiene, including removing plant debris in nursery growing areas and  hot water washing of containers plus removal of diseased,  spore-producing seedlings and trees around the nursery.
                        
                
                                            - 
                            Lilja,
                            Finnish Forest Research Institute, Vantaa, Finland
                                                        E-mail:
                                                            arja.lilja@metla.fi
                                                                                          
- 
                            Poteri,
                            Finnish Forest Research Institute, Suonenjoki, Finland
                                                        E-mail:
                                                            mp@nn.fi
                                                                                
- 
                            Petäistö,
                            Finnish Forest Research Institute, Suonenjoki, Finland
                                                        E-mail:
                                                            rlp@nn.fi
                                                                                
- 
                            Rikala,
                            Finnish Forest Research Institute, Suonenjoki, Finland
                                                        E-mail:
                                                            rr@nn.fi
                                                                                
- 
                            Kurkela,
                            Finnish Forest Research Institute, Vantaa, Finland
                                                        E-mail:
                                                            tk@nn.fi
                                                                                
- 
                            Kasanen,
                            University of Helsinki, Department of Forest Sciences, Helsinki, Finland
                                                        E-mail:
                                                            rk@nn.fi
                                                                                
 
         
     
 
                        
                
                
                                            Category :
                    
                    Research note
                                    
                            
                    
        
            
            article id 702,
                            category
                        Research note
                    
        
        
                            Timo Kurkela,
                            Heikki Nuorteva.
                    
                    
                (1998).
            
                            
                                    Short-needle disease of Scots pine: an abnormal needle length distribution.
                            
                            
                Silva Fennica
                                                            vol.
                                        32
                                                                            no.
                                        1
                                article id 702.
            
                            
                https://doi.org/10.14214/sf.702
            
             
        
                                    
                                    
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                            Short-needle syndrome occurs commonly in southern Finland. The disease  is characterized by abnormal length distribution of the needles in  shoots. In most cases, affected shoots have needles of normal length as  well as very short needles. The short needles are those injured during  the needle elongation period; the tissues formed abnormal  sclerenchymatic structures and wound periderm. One possible cause could  be hemipterous insects feeding on growing needles. Salivary sheaths of  such insects were often present in both deformed needle bases and  undeformed mature tissues.
                        
                
                                            - 
                            Kurkela,
                            Finnish Forest Research Institute, P.O. Box 18, FIN-01301 Vantaa, Finland
                                                        E-mail:
                                                            timo.kurkela@metla.fi
                                                                                          
- 
                            Nuorteva,
                            Finnish Forest Research Institute, P.O. Box 18, FIN-01301 Vantaa, Finland
                                                        E-mail:
                                                            hn@nn.fi