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Robinia pseudoacacia in Europe: distribution, habitat, usage and threats

  • ¹ European Commission, Joint Research Centre (external consultant, ARCADIA SIT) | ² Maieutike Research Initiative


Robinia pseudoacacia L., commonly known as black locust, is a tree native to North America and is one of the most important and widespread broadleaved alien trees in Europe. It is a medium-sized, deciduous, fast-growing thorny tree with high suckering capacity. It has been extensively planted in Europe and now it is naturalised in practically the whole continent. Growing on a wide range of soil types, this tree species only avoids wet or compacted conditions. It is mainly distributed in sub-Mediterranean to warm continental climates and requires a rather high heat-sum. As a light-demanding pioneer species, it rapidly colonises grasslands, semi-natural woodlands and urban habitats, where it can persist for a long time. Owing to the capacity of fixing di-nitrogen through symbiotic rhizobia in root nodules, black locust can add high rates of nitrogen to soil which becomes available to other plants. The wood of black locust is durable and rot-resistant, making it adequate for multiple purposes such as fire and pulp wood, for fences, construction and furniture. In several parts of Europe, black locust is considered an invasive alien plant, because of shading and its ability to change soil conditions.
European Atlas of Forest Tree Species | Tree species
< 25%
25% - 50%
50% - 75%
> 75%
Annual precipitation (mm)
Uncertain, no-data
Marginal/no presence < 5%
Low presence 5% - 10%
Mid-low presence 10% - 30%
Medium presence 30% - 50%
Mid-high presence 50% - 70%
High presence 70% - 90%
Very-high presence > 90%
Robinia pseudoacacia
T. Sitzia, A. Cierjacks, D. de Rigo, G. Caudullo
Robinia pseudoacacia L., commonly known as black locust, is a tree native to North America and is one of the most
important and widespread broadleaved alien trees in Europe. It is a medium-sized, deciduous, fast-growing thorny tree
with high suckering capacity. It has been extensively planted in Europe and now it is naturalised in practically the whole
continent. Growing on a wide range of soil types, this tree species only avoids wet or compacted conditions. It is mainly
distributed in sub-Mediterranean to warm continental climates and requires a rather high heat-sum. As a light-demanding
pioneer species, it rapidly colonises grasslands, semi-natural woodlands and urban habitats, where it can persist for a long
time. Owing to the capacity of fixing di-nitrogen through symbiotic rhizobia in root nodules, black locust can add high rates
of nitrogen to soil which becomes available to other plants. The wood of black locust is durable and rot-resistant, making
it adequate for multiple purposes such as fire and pulp wood, for fences, construction and furniture. In several parts of
Europe, black locust is considered an invasive alien plant, because of shading and its ability to change soil conditions.
The black locust (Robinia pseudoacacia L.) is a medium-sized
deciduous tree that commonly reaches 20 m as a single tree and
30 m within stands1, 2 , but capable of attaining heights up to 35 m
in some locations3. It has a typical life span of about 60-100
years4, although the current longevity record in Europe is for more
than 300 years5. The tree is usually bent-stemmed with greyish-
brown to dark brown bark, becoming longitudinally fissured with
age. The leaves are composed, pinnate, 10-30 cm long, usually
with a pair of spines at the base which persist on young shoots.
The leaflets are commonly in 2-12 pairs, usually opposite, with an
additional one at the end of the rachis. Leaf blades are oblong,
elliptic or ovate, 2-5 × 1.5-2.5 cm, with entire margin. Black locust is
a monoecious species: the hermaphrodite scented flowers have a
white to cream corolla with yellow spots inside, up to 2 cm long and
grouped in pendent, many-flowered, axillary racemes 10-20 cm
long6. Black locust is a monoecious species: the hermaphrodite,
white and fragrant flowers are arranged in pendulous racemes 10-
20 cm long6. The fruit is a legume, 5-10 cm long dark brown pods
hanging in winter and containing 4-10 seeds, mainly dispersed by
gravity and wind7. Fruiting takes place once or twice per year at a
tree age from 6 to 30-40 years8.
Black locust is widespread across Europe, occurring from Sicily
in Italy to South Norway and longitudinally from the Portugal littoral
regions up to the Caucasus9-11 . Core areas in the alien range of this
species are in sub-Mediterranean to warm continental climates, where
a rather high heat-sum is available7 and prolonged drought is rare12.
It can be found from sea level up to 1 640 m in the Southern Alps
(Prosser F., pers. comm., July 1, 2015). The species was introduced
in Europe in the early 17th century. Linnaeus dedicated the genus
name to Jean Robin, who, with his son Vespasien, was among the
first arborists to introduce and cultivate this tree in Europe5. In the late
18th and early 19th century extensive planting of black locust trees
started in Central Europe. Currently it occurs in 42 European countries
and is naturalised in 3213, covering with pure and mixed stands, for
example, 400 000 ha in Hungary14, 200 000 ha in France15, 250 000 ha
in Romania16 and 230 000 ha in Italy17. Although accounted among
the 100 most invasive alien species in Europe11, only a few countries
have policies and initiatives to tackle it18.
Habitat and Ecology
Black locust is a light-demanding pioneer species and
grows either as an upright, single- or multi-stemmed tree or, in
harsh environments, as a multi-stemmed shrub. It tolerates a
remarkably diverse range of soil conditions, being only limited by
low soil aeration and waterlogging. On steep slopes, black locust
is usually less vigorous19. The tree is easily damaged by extreme
frosts in winter and presents low adaptability to arid conditions6, 20.
Climate warming is expected to favour its further expansion21. Its
reproduction is primary asexual through horizontal root elongation22.
It is able to produces a high number of root suckers and therefore
exhibits the capacity for clonal growth, up to an area of 100 square
metres23. Disturbance favours clonal growth and causes an increase
in the number of suckers19. The invasion of black locust is well
documented in early succession habitats, like abandoned gravel-
sand pits and landfills, brownfields, secondary forests, coppiced
forests, lowland pastures, roadsides, and burned sites6. As with
other species of the Fabaceae (syn. Leguminosae) family, the roots
of black locust host rhizobia bacteria in symbiotic relationship within
structures called root nodules. These bacteria have the capacity to
take di-nitrogen gas (N2) out of the air and convert it to a form usable
to the host plant (nitrogen fixation). This process makes nitrogen
available to other plants, mainly through mineralization of leaf litter,
and improves the quality of the soils. Black locust can add between
23 and 300 kg of nitrogen in a hectare every year6. So stands of
black locust may generate substantial soil alterations, increasing the
total soil nitrogen, the litter and the organic carbon, also changing
soil pH and decreasing the total phosphorus6. Its adaptability and
the capacity of transforming ecosystem processes are the reason
for its adverse effects on biodiversity. However, inferior competitive
ability in later successional stages is reported where stands have
been left unmanaged for a sufficient time24. Black locust commonly
contributes to the composition of deciduous woodlands, mainly oak
and riparian woods, which are the most frequently invaded12. Stands
dominated by black locust are cultural forest communities, which
can totally differ from native forest vegetation25. As such, they have
been either classified within the phytosociological separate class
Robinietea or included in other units, as a derivative community26.
Several associations have been described in Central Europe, among
which Balloto-Robinietum (diagnostic species include Ballota
nigra, Bromus sterilis, Dactylis glomerata) on poor aeolian sandy
soils, Solidagino-Robinietum (diagnostic species include Solidago
Robinia pseudoacacia in Europe: distribution, habitat, usage and threats
Robinia pseudoacacia
Black locust invasion has been proven to have an impact on biodiversity
when compared with the native habitats. This applies to both plant34-36 ,
bird37 and lichen38 communities. These effects depend on the stand
age and the landscape type. For example, the presence of black locust
in recent secondary stands in rural landscapes does not seem to play
a major role in shaping the diversity of the understorey plant groups
compared to native stands39. In urban areas, it seems to have the
ability to homogenize processes at the plant community level36. Further
research is needed to elucidate the effect of different management
techniques on the ability of black locust to invade adjacent forest and
semi-natural habitats30.
Biodiversity concerns
Black locust in Berlin, Germany.
(Copyright Giovanni Trentanovi: CC-BY)
Map 1: Plot distribution and simplified chorology map for Robinia pseudoacacia.
Frequency of Robinia pseudoacacia occurrences within the field observations
as reported by the National Forest Inventories.
Map 2: High resolution distribution map estimating the relative probability of presence.
JRC_EFDAC_forest_atlas.indd 166JRC_EFDAC_forest_atlas.indd 166 05/07/2021 17:1405/07/2021 17:14
Tree species | European Atlas of Forest Tree Species 167
Annual average temperature (°C) Potential spring-summer solar irradiation (kWh m-2)
Annual precipitation (mm)
Average temperature of the coldest month (°C)
Sum of precipitation of the driest month (mm)
Seasonal variation of monthly precipitation (dimensionless)
Uncertain, no-data
Tundra, cold desert
Negligible survivability
Low survivability
Mid-low survivability
Medium survivability
Mid-high survivability
High survivability
Field data in Europe (including absences) Observed presences in Europe
Robinia pseudoacacia Robinia pseudoacacia
gigantea) on river valley soils, Chelidonio-Robinietum on slightly
humid soils rich in humus, characterised by an understorey with the
greater celandine (Chelidonium majus) and other species (Sambucus
nigra, Galium aparine, Urtica dioica, Geranium robertianum), and
Poo nemoralis-Robinietum, with herb layer dominated by Poa
nemoralis, on slopes with acid bedrock26.
Importance and Usage
Black locust has been strongly encouraged as a forestry tree
in Europe. The yellow and greenish wood is durable, resistant to
stem rot and insect damage, with a marked contrasted colour
between young and mature wood. Black locust is appreciated
as firewood because of its high calorific potential and the
high suckering capacity which makes coppicing the most cost-
effective management system. The mechanical properties of the
wood is moderate to high, but shrinkage has been observed6, 27.
The potential uses include fence posts, boatbuilding, flooring,
furniture, mine timbers, railway sleepers, turned objects, and
veneer. Moreover, it is a promising fast-growing tree species for
biomass production28. Finally, black locust produces a fruity and
fragrant honey29, and its blossoms are used for cooking. However,
all these uses should consider the risk of further expansion of
black locust in adjacent threatened habitats30.
Threats and Diseases
Large herbivores cause only minor damage to black
locust trees in Europe. Until now, exclusively one gall midge
(Obolodiplosis robiniae) and two moths (Phyllonorycter robiniella
and Parectopa robiniella) are known to cause some damage31, 32.
Many lignicolous fungal species have been detected in the alien
range, of which more than 40 are parasitic. Moreover, 11 mildews
and leaf-spot diseases have been recorded in Germany6. Finally,
some viruses, potentially pathogenic to crops, are known from
the alien range33. In general, threats for black locust in Europe are
much fewer and of lower intensity than those in its native range6.
This is an extended summary of the chapter. The full version of
this chapter (revised and peer-reviewed) will be published online at The purpose of this
summary is to provide an accessible dissemination of the related
main topics.
This QR code points to the full online version, where the most
updated content may be freely accessed.
Please, cite as:
Sitzia, T., Cierjacks, A., de Rigo, D., Caudullo, G., 2016. Robinia
pseudoacacia in Europe: distribution, habitat, usage and
threats. In: San-Miguel-Ayanz, J., de Rigo, D., Caudullo, G., Houston
Durrant, T., Mauri, A. (Eds.), European Atlas of Forest Tree Species.
Publ. Off. EU, Luxembourg, pp. e014e79+
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Long legume which can contain 4-10 seeds.
(Copyright Marinella Zepigi, AP)
Fragrant white flowers clustered in a long raceme.
(Mezzana, Northern Italy).
(Copyright Giulia Corradini: CC-BY: CC-BY)
A stand with a dense carpet of celandines (Chelidonium majus) (Berlin, Germany).
(Copyright Giovanni Trentanovi: CC-BY)
Autoecology diagrams based on harmonised
field observations from forest plots.
Map 3: High resolution map estimating the maximum habitat suitability.
JRC_EFDAC_forest_atlas.indd 167JRC_EFDAC_forest_atlas.indd 167 05/07/2021 17:1405/07/2021 17:14
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... It was planted as an ornamental tree in parks and gardens, but was also used to produce firewood, as a leaf food for animals, as a nectar source for bees, to produce waterproof wood, and to control soil erosion [45,46]. Nowadays, this plant covers more than 2.3 million ha with an area of at least 100,000 ha in Bulgaria, the Czech Republic, France, Hungary, Italy, Poland, Romania, Slovenia, Serbia, and Ukraine [33][34][35][36][47][48][49][50]. Research and studies have shown that the flowers contain flavonoids, condensed tannins, polysaccharides, and essential oil, which have antimicrobial activity against foodborne pathogens [51][52][53]. ...
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Urbanization and climate change are two inevitable megatrends of this century. Knowledge about the growth responses of urban trees to climate is of utmost importance towards future management of green infrastructure with the aim of a sustainable provision of the environmental ecosystem services. Using tree-ring records, this study analyzed growth response to climate by stem diameter at breast height (DBH) of 1178 trees in seven large cities worldwide, including Aesculus hippocastanum L. in Munich; Platanus × hispanica Münchh. in Paris; Quercus nigra L. in Houston; Quercus robur L. in Cape Town; Robinia pseudoacacia L. in Santiago de Chile, Munich, and Würzburg; and Tilia cordata Mill. in Berlin, Munich, and Würzburg. Climate was characterized following the de Martonne aridity index (DMI). Overall, trees showed an 8.3% lower DBH under arid than humid climate at the age of 100. Drought-tolerant tree species were overall not affected by climate. However, R. pseudoacacia showed a lower diameter when growing in semi-dry than humid climate. In contrast, drought-sensitive tree species were negatively affected by arid climate. Moreover, the effect of drought years on annual diameter increment was assessed. P. × hispanica and R. pseudoacacia appeared as the most drought-resistant species. The highest sensitivity to drought was detected in T. cordata and Q. robur. A. hippocastanum and Q. nigra showed a lower diameter growth during drought events, followed by a fast recovery. This study’s findings may contribute to a better understanding of urban tree growth reactions to climate, aiming for sustainable planning and management of urban trees.
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Black locust (Robinia pseudoacacia) is recognised as a forest species of interest due to its multiple uses. The management of forest genetic resources and their efficient conservation suffer from variations in traits and start with seed germination. The aim of the current study was to investigate the germination of seeds obtained from plus trees selected in eight Romanian provenances, as well as to investigate the influence of the origin upon plants’ growth and development. Two experiments were undertaken to test seed germination: one treatment involved water-soaked seeds and heat/cold treatment, while the other treatment was based on sulphuric acid, at different concentrations (50, 70, 90%). The results were correlated with the morphological analysis of the seeds. Satu-Mare had the lowest germination rate within both treatments. Sulphuric acid did not improve seed germination as much as the heat treatment. The highest germination rate occurred for the water and temperature treatment on seeds from Bihor provenance (68.2%). The most distant provenance was Bihor, in inverse correlation with Bistrița Năsăud and grouped separately within the hierarchical dendrogram of cluster analysis based on the analysed parameters of the provenances investigated. The results demonstrated that the genotypes and environmental heterogeneity of the seed origin within the provenances may finally result in different performances.
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Forests (either natural or planted) play a key role in climate change mitigation due to their huge carbon-storing potential. In the 1980s, the Hellenic Public Power Corporation (HPPC) started the rehabilitation of lignite post-mining areas in Northwest Greece by planting mainly black locust (Robinia pseudoacacia L.). Today, these plantations occupy about 2570 ha, but the accumulation of Above Ground Biomass (AGB) and deadwood has not been assessed to date. Therefore, we aimed at estimating these biomass pools by calibrating an allometric model for AGB, performing an inventory for both pools and predicting the spatial distribution of AGB. 214 sample plots of 100 m2 each were set up through systematic sampling in a grid dimension of 500 × 500 m and tree dbh and height were recorded. AGB was estimated using an exponential allometric model and performing inventory measurements and was on average 57.6 t ha−1. Kriging analysis reliably estimated mean AGB, but produced errors in the prediction of high and low biomass values, related to the high fragmentation and heterogeneity of the studied area. Mean estimated AGB was low compared with European biomass yield tables for black locust. Similarly, standing deadwood was low (6–10%) and decay degrees were mostly 1 and 2, indicating recent deadwood formation. The overall low biomass accumulation in the studied black locust restoration plantations may be partially attributed to their young age (5–30 years old), but is comparable to that reported in black locust restoration plantation in extremely degraded sites. Thus, black locust successfully adapted to the studied depositions of former mines and its accumulated biomass has the potential to improve the carbon footprint of the region. However, the invasiveness of the species should be considered for future management planning of these restoration plantations.
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The effects of black-locust invasion on plant forest diversity are still poorly investigated. Vascular plants are likely to be influenced by increasing nutrient availability associated with the nitrogen-fixing activity of black-locust, whereas it is not clear if, along with stand aging, black-locust formations regain forest species. The main aim of the present study was to test whether the increase of black-locust stand age promoted a plant variation in mature stands leading to assemblages similar to those of native forests. Therefore, plant richness and composition of stands dominated by native trees were compared with pure black-locust stands of different successional stages. Our study confirmed that the replacement of native forests by pure black-locust stands causes both plant richness loss and shifts in species composition. In black-locust stands plant communities are dominated by nitrophilous species and lack many of the oligothrophic and acidophilus species typical of native forests. Plant communities of native forests are more diverse with respect to pure black-locust stands, suggesting that black-locust invasion also causes a homogenization of the plant forest biota. We did not detect differences across the successional gradient of black-locust stands, and mature stands do not recover the diversity of plant species which are lost by the replacement of the native forests by black-locust. Accordingly some efforts in reducing the negative impacts of black-locust invasion on plant forest biota should be focused at least in those areas where conservation is among management priorities, such in the case of habitats included in the Habitat Directive (92/43 ECE).
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Synanthropic forest and shrub vegetation dominated by Robinia pseudacacia spontaneously growing in the open landscape and suburban areas in Bohemia (Czech Republic) was analysed. In total, 374 of 502 known phytosociological relevés were synthesized - 302 relevés were sampled in the field and 72 published relevés were obtained from the literature. Within the class Robinietea (including two orders and three alliances) one association is validated and two new subassociations are described: Arrhenathero elatioris-Robinietum (including var. Calamagrostis epigejos), Poo nemoralis-Robinietum cardaminopsietosum arenosae and Poo nemoralisRobinietum typicum. Currently, four associations of these Black Locust stands from Bohemia are recognised: Chelidonio-Robinietum, Poo nemoralis-Robinietum, Arrhenathero elatioris-Robinietum, and Melico transsilvanicae-Robinietum. The description of several units is amended with synecological characteristics (altitude, aspect, slope, bedrock, soil type, and important physicochemical and biochemical characteristics) and distribution both in Bohemia and, according to hints in the literature, also in Central European countries. The position of Black Locust stands in the syntaxonomical system is discussed, and nomenclatural types and diagnostic species combinations of higher syntaxa are given. The current level of knowledge of Black Locust stand classification in Central Europe is compared.
This study examined the factors that influence the size of a soil seed bank in Robinia pseudoacacia stands. We proposed two hypotheses: the amount of buried seeds of R. pseudoacacia is proportional to stand biomass rather than stand age, and apicultural utilization influences the size of the soil seed bank. R. pseudoacacia generally produces seeds with various degrees of physical dormancy. In addition, this tree is short-lived, and fecundity declines after 30–40 years in relation to tree vigor. However, R. pseudoacacia is intensively used in apiculture as an important honey source, and supply of honeybees by beekeepers could influence seed crops. We investigated 25 plantations in Hokkaido (Central, Hidaka, and Oshima) and in Nagano, Japan, where many naturally regenerated R. pseudoacacia stands occur. We found great variation in the size of the soil seed bank among stands, ranging from 13,757 to 6.4seedsm−2 per plot. A generalized linear mixed model revealed that both basal area (BARp) and apicultural utilization best explained the size of the soil seed bank. Both the positive effect of BARp and small contribution of stand age to the model implied that the soil seed bank is transitory, and will not persist for very long time. The large contribution of apicultural utilization to the size of the soil seed bank implied pollinator limitation under natural conditions. R. pseudoacacia often has large flower crops, and native pollinators can not keep up with the demand for pollination. Thus, the supply of honeybees by beekeepers should improve the pollination success of R. pseudoacacia. From these results, we conclude that we must consider stand history with respect to apicultural utilization if the land is harvested or a stand declines.
The objective of this study was to characterize black locust (Robinia pseudoacacia L.) wood on the basis of its physical and mechanical properties. The results are compared with those reported in the literature for English oak (Quercus robur L.), teak (Tectona grandis L. f.), and afzelia (Afzelia sp.), since black locust is likely to be used for the same purposes as the former species. The variations between sites, trees, and radial positions in the trunk were also studied. The physical and mechanical properties of black locust wood were evaluated on clear wood specimens taken from 27 trees distributed over five sites in Wallonia (Belgium) according to Belgian and French standards. Most of the black locust’s mechanical properties are higher than those of oak and teak. The black locust is classified as a “mid-heavy” (734 kg·m–3) and “half-hard” (5.22) wood type with very high resilience (17.2 J·cm–2), modulus of elasticity (15 700 MPa), and tensile strength in static bending (138 MPa). Its resilience is exceptional, higher than that of teak and afzelia, while its modulus of elasticity and bending strength, which surpass those of teak, are comparable with those of afzelia. Black locust shows high total volumetric shrinkage (16%), placing it in the “nervous” class, average tangential (8.8%) and radial shrinkage (5.5%) as well as average axial compressive (63 MPa) and splitting strength (17.8 N·mm–1). No technological incompatibilities would prevent the use of this wood for many value-added purposes (floor, deck, exterior woodwork, and furniture); however, significant shrinkage makes it necessary to condition the wood to its service moisture.
Aim Urbanization as a major global trend profoundly changes biodiversity patterns, and homogenization of urban biota due to expanding exotic species and declining native species is of increasing concern. Previous studies on this topic have mostly taken place at large scales that include high habitat heterogeneity. Here, we aimed at disentangling the effects of urbanization and plant invasion on species composition through the analysis of similarity patterns of urban plant assemblages at the community scale where species interact. Location Berlin, Germany. Methods We analysed how different levels of urbanization, specific components of the urban matrix and the dominance of a native (Betula pendula) versus an exotic tree species (Robinia pseudoacacia) affect alpha and beta diversity of urban woodland understorey vegetation in sixty-eight 100-m2 plots. Results Exotic dominance reduced alpha diversity, but not beta diversity of the total species pool. Comparing beta diversity among different species groups revealed significant but divergent effects of exotic dominance, habitat connectivity and levels of urbanization in native and non-native species assemblages. In particular, urbanity proved to homogenize the native species pool, whereas the beta diversity of the non-native species pool showed a more pronounced response to exotic dominance. Main conclusions Our data provide evidence that both the urban context and the dominance of exotic species can modify homogenization processes at the community level. These novel insights into the mechanisms of biotic homogenization of urban floras may contribute to mitigating the effects of urbanization on biodiversity.
Black or common locust was introduced into Hungary between 1710 and 1720. Its present extent is 276 000 ha, 18.2% of the total forest area. Since its introduction, black locust has always been closely associated with farming.Selection breeding followed numerous steps. The best shipmast-type groves in the best stands were surveyed for superior trees which were grafted for clone tests.The National Agricultural Council for Variety Testing approved three selected or introduced locust cultivars in 1973 and five more in 1979. The registered cultivars and a further 13 candidates are grouped into three categories according to their proposed uses: sawlogs; poles and posts; and finally beekeeping and decorative planting.Some cultivars such as ‘Zalai’, ‘Kiskunsági’, ‘Császártöltési’, ‘Egylevelü’ and ‘Váti 46’ are suitable both for forestry and beekeeping.Vegetative propagation systems have been introduced for mass propagation of the improved cultivars. The planned production of 8 million plants in 1984 covers two-thirds of the demand.The selected cultivars demand intensive technologies, of which planting after deep-ploughing on better sites is the best. Silvicultural models have been worked out for producing sawlogs on better sites and poles and posts on medium sites.Interest in black locust is growing both in Europe and Asia. The area of man-made locust stands has increased in the last 20 years from 337 000 to 1 890 000 ha. These figures exclude China, where the tree is extensively used. In recent years the energy and forage aspects have become more interesting. South Korea leads in this respect, but various projects are also being undertaken in Hungary.
Three isolates of Strawberry latent ringspot virus (SLRSV) were obtained from black locust (Robinia pseudoacacia L.): SLRSV-G2, SLRSV-N31 and SLRSV-W16. The isolates were identified by the host range, particle morphology, serological properties and virus-specific reverse transcription polymerase chain reaction. The studies showed that two Polish isolates: SLRSV-N31 and SLRSV-W16 are almost identical, while the SLRSV-G2 isolate is remarkably different. Phylogenetic analysis confirmed that SLRSV-G2 is also distinct from others reported to date. Pairwise comparisons of SLRSV-G2 with other isolates available in GenBank database showed only 76–79% nucleotide similarity. Therefore, SLRSV-G2 is proposed as a new strain of SLRSV.