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Non-native tree (NNT) species have been transported worldwide to create or enhance services that are fundamental for human well-being, such as timber provision, erosion control or ornamental value; yet NNTs can also produce undesired effects, such as fire proneness or pollen allergenicity. Despite the variety of effects that NNTs have on multiple ecosystem services, a global quantitative assessment of their costs and benefits is still lacking. Such information is critical for decision-making, management and sustainable exploitation of NNTs. We present here a global assessment of NNT effects on the three main categories of ecosystem services, including regulating (RES), provisioning (PES) and cultural services (CES), and on an ecosystem disservice (EDS), i.e. pollen allergenicity. By searching the scientific literature, country forestry reports, and social media, we compiled a global data set of 1683 case studies from over 125 NNT species, covering 44 countries, all continents but Antarctica, and seven biomes. Using different meta-analysis techniques, we found that, while NNTs increase most RES (e.g. climate regulation, soil erosion control, fertility and formation), they decrease PES (e.g. NNTs contribute less than native trees to global timber provision). Also, they have different effects on CES (e.g. increase aesthetic values but decrease scientific interest), and no effect on the EDS considered. NNT effects on each ecosystem (dis)service showed a strong context dependency, varying across NNT types, biomes and socio-economic conditions. For instance, some RES are increased more by NNTs able to fix atmospheric nitrogen, and when the ecosystem is located in low-latitude biomes; some CES are increased more by NNTs in less-wealthy countries or in countries with higher gross domestic products. The effects of NNTs on several ecosystem (dis)services exhibited some synergies (e.g. among soil fertility, soil formation and climate regulation or between aesthetic values and pollen allergenicity), but also trade-offs (e.g. between fire regulation and soil erosion control). Our analyses provide a quantitative understanding of the complex synergies, trade-offs and context dependencies involved for the effects of NNTs that is essential for attaining a sustained provision of ecosystem services.

Norway spruce (Picea abies (L.) Karst.) seed is collected from both forest stands after final felling and from seed orchards. To produce high-germinability seed lots that are easy to use in nursery sowing machines, empty, insectdamaged, and other poor-quality seeds are culled. Sorting is done typically by weight or size. Previous studies of conifer seed have indicated wide variation in seed weight between individual trees or clones. However, the intratree or intraclone variations have rarely been taken into account, and intracone variation in seed weight has not been examined. We collected cones from a forest stand and from a clonal seed orchard in central Finland. Each seed from each cone was extracted, weighed, and x-rayed to assess their quality. Trees and clones differed in terms of the proportions of different quality seed. Variance component analysis showed that the intracone variation explained a larger proportion of the total variation in seed weight than did the intercone/intertree or interclone variations. Thus weight-based seed sorting has less effect on the genetic diversity of a seed lot than previously believed. We also conclude that the large differences in proportion of full seed among trees and clones impact the contribution of genotypes in seed and, eventually, in seedling lots. Key words: cone insect, Norway spruce, radiography, seed orchard, stand seed. Les graines d'epicea commun (Picea abies (L.) Karst.) sont recoltees dans les peuplements forestiers apres la coupe finale et dans les vergers a graines. Pour produire des lots de graines qui ont un taux eleve de germination et sont faciles a utiliser dans les semoirs en pepiniere, les graines vides, endommagees par les insectes ou de mauvaise qualite sont eliminees. Le tri est typiquement effectue sur la base du poids ou de la taille. Les etudes precedentes sur les graines de conifere ont revele qu'il y avait une grande variation du poids des graines entre les arbres ou les clones. Cependant, la variation parmi les graines d'un meme arbre ou d'un meme clone a rarement ete consideree et la variation du poids des graines dans un meme cone n'a pas ete etudiee. Nous avons recolte des cones dans un peuplement forestier et dans un verger a graines clonal dans le centre de la Finlande. Chaque graine de chaque cone a ete extraite, pesee et radiographiee pour en evaluer la qualite. Les arbres et les clones etaient differents en termes de proportions de graines de differentes qualites. L'analyse des composantes de la variance a montre que la variation entre les graines d'un meme cone expliquait une plus grande proportion de la variation totale du poids des graines que la variation entre les cones, entre les arbres ou entre les clones. Par consequent, le tri des graines sur la base du poids a moins d'effet sur la diversite genetique d'un lot de graines qu'on le croyait. Nous concluons egalement que les grandes differences entre les arbres et les clones quant a la proportion de graines pleines ont un impact sur la contribution des genotypes dans les lots de graines et eventuellement dans les lots de semis. [Traduit par la Redaction] Mots-cles: insecte ravageur des cones, epicea commun, radiographie, verger a graines, graines provenant d'un peuplement., 1. Introduction In Finland, approximately 1100 kg of Norway spruce (Picea abies (L.) Karst.) seed is used annually in nurseries to produce seedlings for forest regeneration. Recently (2002-2012), 15%-78% of [...]

Genotypic tradeoffs along environmental gradients help maintain diversity in functional traits in the wild and limit the range of suitable environments for each genotype in tree breeding programmes. Little is still known of the capacity of abiotic and biotic soil variation to generate marked shifts in genotypic performance ranks. We examined the potential of belowground soil factors to bring about genotype × environment interactions in a tree species by combining data from extant field trials and a new seedling-based progeny experiment. We first analysed genotypic growth patterns of Norway spruce (Picea abies) at two field trial locations, a native forest site and a former agricultural field, that exhibited biotic and abiotic soil variation. While we found significant genotype × location interactions in growth, we also observed positive between-location genotypic correlations, indicating similar genotypic rank orders across divergent soil types. Contributing to the genotype × environment interactions, differences in age at the time of growth measurements may explain why genetic variances nevertheless differed between the locations. The subsequent progeny experiment with soil and seeds collected at the trial locations enabled controlled treatments in a growth chamber that tested the capacity of between-location soil variation to induce genotype × environment interactions in seedling traits. The progeny experiment revealed that the soil treatment had major effects on averages in all 14 shoot and root functional traits, with four groups of correlated traits (e.g., estimates of shoot and root system size) identified by a principal component analysis. Seed collection location affected only few traits, and the more southern agricultural field trial yielded slightly larger seedlings with delayed phenology. Yet, despite significant genetic variation, no seedling trait manifested genotype × soil treatment interactions, which may be due to the soil treatments not mirroring spatial heterogeneity of the soils at the trial locations, or to our limited subsample of ten genotypes in the progeny experiment. Taken together, our results on adult trees and seedlings indicate that overall tree growth is impacted by variation in belowground environmental factors, but further research with more comprehensive sampling is needed to determine whether they have potential to generate location-specific patterns of genotypic performance in economically valuable tree species. • Biotic and abiotic soil variation may cause genotypic tradeoffs in Norway spruce. • We combined observations from two field trials and a new progeny experiment. • We found tradeoffs in growth in adult trees, but not in seedling functional traits. • Genetic and soil variation had independent effects on functional trait variation. [ABSTRACT FROM AUTHOR]

Combining pheromone trapping and genetic analyses can be useful when trying to resolve complexes of closely related insect taxa that are difficult to distinguish based on morphological characters. Nearctic and Palearctic populations of the spruce seed moth, Cydia strobilella L., have been considered taxonomically synonymous since 1983, but more recent work revealing distinct sex pheromones for Canadian and Swedish moths suggest that populations in the two regions belong to different species. In order to test this hypothesis, we performed field trapping using different pheromone lures at ten sites in North America, Europe and Asia, and reconstructed phylogenetic relationships among trapped moths using mitochondrial ( cytochrome oxidase subunit I) and nuclear ( elongation factor 1 alpha) DNA sequence data. Trapping data and tree topologies for both genes revealed distinct pherotypes in North America and Eurasia. A genetically distinct population from China was investigated further with respect to its sex pheromone. Electrophysiological data indicated that Chinese females produce a deviant ratio of the sex pheromone components (dienic acetates) compared to Swedish females. However, trapping experiments in both areas revealed a similar broad response profile in males to a wide range of acetate ratios, and these populations should be considered taxonomically synonymous. A previous suggestion of an agonistic effect on the attraction of C. strobilella males in Sweden when adding the corresponding alcohols to the binary acetate blend was also tested in Sweden as well as in China, with no observed effect on attraction of males. In conclusion, our study demonstrates the great potential of using pheromone trapping as a tool for identification and delimitation of taxa within cryptic species complexes. Based on our data, Nearctic and Palearctic populations of C. strobilella should be considered different species, and C. youngana Kearfott stat. rev. is resurrected here as valid name for North American populations, which was the case before the revision in 1983. [ABSTRACT FROM AUTHOR]

Plants are assumed to have a trade-off between growth and resistance. This trade-off has been demonstrated in herbaceous plants, but the information on woody plants is conflicting. In contrast to simple annual plant–herbivore systems, trees face highly variable herbivory. In this note, we measured clonal variation in the growth of Betula pendula and in its resistance to nine major herbivore species belonging to five different feeding guilds. There were significant differences in both the growth and the resistance of clones to all the herbivores studied. However, we found no negative correlation between growth and resistance. No clone was generally resistant or susceptible to most of the herbivores. This suggests that, if there is an ultimate trade-off in resource allocation of B. pendula between growth and resistance, it is masked by other factors, for example, by several opposite abiotic and biotic selection pressures. [Copyright &y& Elsevier]