Interfertility and clonal size in the Armillariella mellea complexKARl KORHONEN KORHONEN, K. 1978: Interfertility and clonal size in the Armillariella mellea complex.-Karstenia 18: 31-42.The Armillariella me/lea complex in Finland is divided on the basis of mating experiments into three completely intersterile biological species with different morphological and ecological characteristics. Their nomenclature is still unclear. They are intersterile with A. me/lea (Vahl ex Fr.) Karst. sensu stricto and A. bulbosa (Barla) Romagn., collected in France. All these five species exhibit a heterothallic bifactorial mating system, and in four species a similar mechanism of somatic diploidization in compatible mating has been observed. The diploid pure cultures belonging to these species can be identified in mating tests with the aid of the Buller phenomenon.Two species are common in Finland . They are predominantly saprophytes and occur to some extent in the butt rot of Picea abies. The third species is a pathogen of Pinus sylvestris saplings and has been found only in the southern part of the country. Some information about the occurrence of these species outside Finland is presented.The naturally occurring clones of Armillariella species have been identified by using incompatibility factors as genetic markers and on the basis of demarcation line formation in confrontations between diploid pure cultures. The results obtained with these two methods are in good agreement. The usual diameter of A rmillariella clones in Finland is 10-50 m. The largest clones found had a diameter of 120-150 m.

Estimation of forest canopy cover has recently been included in many forest inventory programmes. In this study, after discussing how canopy cover is defined, different ground-based canopy cover estimation techniques are compared to determine which would be the most feasible for a large scale forest inventory. Canopy cover was estimated in 19 Scots pine or Norway spruce dominated plots using the Cajanus tube, line intersect sampling, modified spherical densiometer, digital photographs, and ocular estimation. The comparisons were based on the differences in values acquired with selected techniques and control values acquired with the Cajanus tube. The statistical significance of the differences between the techniques was tested with the nonparametric Kruskall-Wallis analysis of variance and multiple comparisons. The results indicate that different techniques yield considerably different canopy cover estimates. In general, labour intensive techniques (the Cajanus tube, line intersect sampling) provide unbiased and more precise estimates, whereas the estimates provided by fast techniques (digital photographs, ocular estimation) have larger variances and may also be seriously biased.Keywords forest canopy, canopy cover, canopy closure, Cajanus tube, line intersect sampling, spherical densiometer, digital photographs Addresses University of Joensuu, P.O. Box 68, FI-68101 Joensuu, Finland E-mail lauri.korhonen@joensuu.fi Received 12 April 2006 Revised 22 September 2006 Accepted 26 September 2006 Available at http://www.metla.fi/silvafennica/full/sf40/sf404577.pdf tion of forest canopy cover has recently become an important part of forest inventories. First, canopy cover has been shown to be a multipurpose ecological indicator, which is useful for distinguishing different plant and animal habitats, assessing forest floor microclimate and light conditions, and 578 Silva Fennica 40(4), 2006 research articles estimating functional variables like the leaf area index (LAI) that quantifies the photosynthesizing leaf area per unit ground area (Jennings et al. 1999, Lowman and Rinker 2004). Secondly, many remote sensing applications involve estimation of either canopy cover (Gemmell 1999) or individual tree canopy area (Kalliovirta and Tokola 2005) as an intermediate stage in distinguishing the signals reflected from forest canopy and forest floor, after which, for instance, estimation of timber volume becomes possible (Bolduc et al. 1999). Canopy cover is also an important ancillary variable in the estimation of LAI using empirical or physically based vegetation reflectance models (Jasinski 1990, Spanner et al. 1990, Nilson and Peterson 1991, Knyazikhin et al. 1998, Kuusk and Nilson 2000. The validation of canopy cover estimates obtained from remotely sensed data and development of new remote sensing techniques require field-based canopy cover measurements. Finally, the international definition of a forest is based on canopy cover: the United Nations Food and Agricultural Organization (FAO) has defined forest as land of at...

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Armillaria possesses several intriguing characteristics that have inspired wide interest in understanding phylogenetic relationships within and among species of this genus. Nuclear ribosomal DNA sequence-based analyses of Armillaria provide only limited information for phylogenetic studies among widely divergent taxa. More recent studies have shown that translation elongation factor 1-α (tef1) sequences are highly informative for phylogenetic analysis of Armillaria species within diverse global regions. This study used Neighbor-net and coalescence-based Bayesian analyses to examine phylogenetic relationships of newly determined and existing tef1 sequences derived from diverse Armillaria species from across the Northern Hemisphere, with Southern Hemisphere Armillaria species included for reference. Based on the Bayesian analysis of tef1 sequences, Armillaria species from the Northern Hemisphere are generally contained within the following four superclades, which are named according to the specific epithet of the most frequently cited species within the superclade: (i) Socialis/Tabescens (exannulate) superclade including Eurasian A. ectypa, North American A. socialis (A. tabescens), and Eurasian A. socialis (A. tabescens) clades; (ii) Mellea superclade including undescribed annulate North American Armillaria sp. (Mexico) and four separate clades of A. mellea (Europe and Iran, eastern Asia, and two groups from North America); (iii) Gallica superclade including Armillaria Nag E (Japan), multiple clades of A. gallica (Asia and Europe), A. calvescens (eastern North America), A. cepistipes (North America), A. altimontana (western USA), A. nabsnona (North America and Japan), and at least two A. gallica clades (North America); and (iv) Solidipes/Ostoyae superclade including two A. solidipes/ostoyae clades (North America), A. gemina (eastern USA), A. solidipes/ostoyae (Eurasia), A. cepistipes (Europe and Japan), A. sinapina (North America and Japan), and A. borealis (Eurasia) clade 2. Of note is that A. borealis (Eurasia) clade 1 appears basal to the Solidipes/Ostoyae and Gallica superclades. The Neighbor-net analysis showed similar phylogenetic relationships. This study further demonstrates the utility of tef1 for global phylogenetic studies of Armillaria species and provides critical insights into multiple taxonomic issues that warrant further study.

Tässä julkaisusssa esitetään valtakunnan metsien 10. inventointiin (VMI10) perustuvat tiedot Suomen metsävaroista ja metsien tilasta. Maastotiedot on kerätty vuosina 1996-2004. Tulokset esitetään metsäkeskusalueittain, osa tuloksista myös puuntuotannon rajoitusten ja metsänomistajaryhmän mukaan jaoteltuna. Metsien kehitystä tarkastellaan vertailemalla tuloksia aiempien inventointien tuloksiin 1920-luvun alun VMI1:stä lähtien. Julkaisussa esitetään myös VMI10:ssä käytetyt mittaus-ja laskentamenetelmät.Suomen metsien puumäärä on jatkanut lisäystään. Puuston kokonaistilavuus on 2,2 miljardia kuutiometriä, kun 1920-luvun alussa nykyisen Suomen puuston määrä oli 1,4 miljardia kuutiometriä. Puuston vuotuinen kasvu oli inventointia edeltäneillä 5 vuoden mittausjaksoilla lähes 100 miljoonaa kuutiometriä. Suomen metsissä nuorien metsien osuus on suuri, mikä selittää puumäärän lisäystä ja puuston lisääntyvää kasvua. Soiden ojitus on lisännyt metsämaan alaa noin 1,5 miljoonaa hehtaaria, mikä myös selittää puuston määrän ja kasvun lisäystä. Edelliseen inventointiin verrattuna metsämaan ala on kuitenkin pienentynyt maanrakennustoiminnan vaikutuksesta.Metsien terveydentila on hyvä, vakavia tuhoja havaittiin inventoinnissa vain noin 4 %:lla metsämaan alasta. Metsähoidollinen tila on tyydyttävä -73 % puuntuotannon metsämaan metsistä on metsänhoidolliselta tilataan hyviä tai tyydyttäviä. Nuorissa metsissä on kuitenkin aiempaa enemmän kiireelliä taimikonhoito-ja ensiharvennustarpeita.Metsä-, kitu-ja joutomaan alasta noin 2 %:lla on arvokkaita biotooppeja, jotka VMI:n maastoarvion mukaan todennäköisesti täyttävät metsälain 10 pykälän kriteerit lukuun alueellista yleisyyttä, johon VMI:n arvioinnissa ei ole otettu kantaa. Arvokkaat elinympäristöt on otettu hyvin huomioon metsien käsittelyssä. Lahopuuston määrä on edelliseen inventointiin verrattuna lisääntynyt Etelä-Suomessa, mutta näyttäisi hieman pienentyneen Pohjois-Suomessa.