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A prioritization process for invasive alien plant species incorporating
the requirements of EU Regulation no. 1143/2014
E. Branquart
1
, G. Brundu
2
, S. Buholzer
3
, D. Chapman
4
, P. Ehret
5
, G. Fried
6
, U. Starfinger
7
,
J. van Valkenburg
8
and R. Tanner
9
1
Invasive Species Unit, Service Public de Wallonie, Gembloux (Belgium); e-mail: etienne.branquart@spw.wallonie.be
2
University of Sassari, Sassari (Italy)
3
Agroscope Institute for Sustainability Sciences, Zurich (Switzerland)
4
NERC Centre for Ecology and Hydrology, Edinburgh (UK)
5
Ministry of Agriculture, National Plant Protection Organization, Montpellier Cedex 2 (France)
6
Anses, Laboratoire de la Sant
e des V
eg
etaux, Unit
e Entomologie et Plantes Invasives, Montferrier-sur-Lez Cedex (France)
7
Julius K€
uhn Institut (JKI), Federal Research Centre for Cultivated Plants, Institute for National and International Plant Health,
Braunschweig (Germany)
8
National Plant Protection Organization, Wageningen (The Netherlands)
9
European and Mediterranean Plant Protection Organization, Paris, France
When faced with a large species pool of invasive or potentially invasive alien plants, priori-
tization is an essential prerequisite for focusing limited resources on species which inflict
high impacts, have a high rate of spread and can be cost-effectively managed. The prioriti-
zation process as detailed within this paper is the first tool to assess species for priority for
risk assessment (RA) in the European Union (EU) specifically designed to incorporate the
requirements of EU Regulation no. 1143/2014. The prioritization process can be used for
any plant species alien to the EU, whether currently present within the territory or absent.
The purpose of the prioritization is to act as a preliminarily evaluation to determine which
species have the highest priority for RA at the EU level and may eventually be proposed
for inclusion in the list of invasive alien species of EU concern. The preliminary risk assess-
ment stage (Stage 1), prioritizes species into one of four lists (EU List of Invasive Alien
Plants, EU Observation List of Invasive Alien Plants, EU List of Minor Concern and the
Residual List) based on their potential for spread coupled with impacts. The impacts on
native species and ecosystem functions and related ecosystem services are emphasized in
line with Article 4.3(c) of the Regulation. Only those species included in the EU List of
Invasive Alien Plants proceed to Stage 2 where potential for further spread and establish-
ment coupled with evaluating preventative and management actions is evaluated. The output
of Stage 2 is to prioritize those species which have the highest priority for a RA at the EU
level or should be considered under national measures which may involve a trade ban, ces-
sation of cultivation, monitoring, control, containment or eradication. When considering
alien plant species for the whole of the EPPO region, or for species under the Plant Health
Regulation, the original EPPO prioritization process for invasive alien plants remains the
optimum tool.
Introduction
The European Union (EU) recently adopted Regulation no.
1143/2014 (EU, 2014) as a coherent regulatory framework
aimed at preventing, minimizing and mitigating the adverse
impacts of invasive alien species (IAS) on biodiversity and
related ecosystem services, as well as adverse impacts on
human health or the economy, which are considered as an
aggravating factor. The core of this new Regulation is a list
of invasive alien species of EU concern (the Union List)
for which Member States have to take action to ensure that
listed IAS are not intentionally brought into, sold and bred
or cultivated within EU territory. In addition, such species
should be carefully monitored through a dedicated surveil-
lance system and subjected to management actions aimed
at eradicating, containing or controlling their populations.
As potential IAS are numerous, it is important to ensure
that priority is given to addressing species considered to be
of EU concern based on: (i) the significance of their detri-
mental impacts and (ii) on the capacity of Member State(s)
to put measures in place to prevent, minimize and mitigate
those impacts in a cost-efficient manner. This means the
two most important elements of risk analysis (IPPC, 2007;
EFSA Scientific Committee, 2012), i.e. risk assessment and
ª2016 The Authors. Journal compilation ª2016 OEPP/EPPO, EPPO Bulletin 46, 603–617 603
Bulletin OEPP/EPPO Bulletin (2016) 46 (3), 603–617 ISSN 0250-8052. DOI: 10.1111/epp.12336
risk management should be addressed to justify any inclu-
sion in the EU List.
The significance of adverse impacts of IAS included in
the Union List has to be justified by a risk assessment (RA)
pursuant to the applicable provisions under the relevant
Agreements of the World Trade Organization (WTO) on
placing trade restrictions on species. The RA has to comply
with common criteria described in Article 5.1 of the Regu-
lation from which minimum standards for RA protocols
have been derived (Roy et al., 2014).
The production and endorsement of RA reports is a time-
and resource-demanding exercise that cannot be conducted
for every IAS that is a potential threat to the EU. This exer-
cise should be restricted to those that best meet the criteria
and principles addressed by the Regulation, for which a
standardized and operational approach is still needed. The
purpose of the prioritization process for EU invasive alien
plant species is to determine which species have the highest
priority for a RA at the EU level in order to be considered
for inclusion in the Union List. The process is adapted from
the EPPO prioritization process for invasive alien plants
(EPPO Standard PM 5/6)
1
prepared under the umbrella of
the International Plant Protection Convention. The adapted
prioritization process has been specifically elaborated within
the framework of the LIFE Project (LIFE15 PRE FR 001)
‘Mitigating the threat of invasive alien plants to the EU
through pest risk analysis to support the Regulation 1143/
2014’ (see http://www.iap-risk.eu), and is designed to
assess alien plants which pose a threat to the EU, but its
logical framework could be easily adapted for other taxo-
nomic groups. According to the Regulation, the area taken
into consideration in the process is the territory of the EU,
excluding the outermost regions.
It should be noted that the prioritization process is
designed to perform rapid prioritization and to provide
structured and traceable information on specific aspects of a
species. It does not in any way provide a substitute for a
full RA.
The prioritization process may be summarized under the
form of a decision scheme, as illustrated in Fig. 1, for
which detailed guidance is provided in this paper. It follows
a two-stage approach taking into account risk assessment
(Stage 1) and risk management (Stage 2) issues.
Methods
The process can be used for any plant species, subspecies
or lower taxa. It consists of compiling available information
on the assessed alien species according to predetermined
criteria.
The process produces lists of plant species compliant
with the main principles and criteria of the Regulation, the
most important being the EU List of Invasive Alien Plants
and the List of Priority Invasive Alien Plants for perform-
ing a RA at the EU level. The process is summarized in
Fig. 1.
Available sources of information to run the process
include: the scientific literature, personal communications
from scientists, NPPO data and websites and databases on
invasive alien plants (e.g. the CABI Invasive Species Com-
pendium, the EPPO Global Database and the IUCN Global
Invasive Species Database). Information needs to be
updated on a regular basis. All references and contacts need
to be recorded to allow traceability.
Whenever possible, evidence should be obtained from
previously observed invasive behaviour in Europe. How-
ever, information on invasive behaviour elsewhere in the
world is of utmost importance for species that are not yet
established in the EU. When contradictory information is
found within the EU, the worst case should be considered
(but see also the rules for uncertainty below). When docu-
menting each species, as much information as possible
should be included and references should be provided, indi-
cating where the documented impacts have been observed,
in order to be able to differentiate between impacts that
actually occurred in the area under assessment and potential
impacts. When describing the process in this document, for
each question examples are provided for a given biogeo-
graphical area or country. Communication between experts
may be organized to increase the quality of the outcome of
this process. For questions that need a rating, a three-point
scale (low, medium, high) is used.
Uncertainty should be recorded for the answers to ques-
tions on spread and impact, and should be summarized in
an overall uncertainty rating of low, medium or high. The
elements of uncertainty should be described. The assessor
may consider an assessment as having some degree of
uncertainty for the following reasons:
•the species is absent from the EU, newly arrived or of
limited distribution, and the impacts are recorded for a
different continent
•there is little or no data available on the species
•the species, although present in the EU, exhibits different
behaviours in different places, or there is conflicting
information available.
Uncertainty therefore depends on the presence or absence
of the plant in the EU, the availability of data on its beha-
viour and possible conflicting information. A matrix indi-
cating uncertainty ratings is provided in Table 1.
Outcomes
Stage 1 of the process addresses preliminary issues of RA
and allocates species to different lists of alien plants within
the EU.
•The EU List of Invasive Alien Plants contains species
which comply with the IAS definition and criteria of Arti-
cle 4 of the Regulation, i.e. alien species that would be
capable of causing major detrimental impacts to
1
EPPO (2012), PM 5/6(1) EPPO prioritization process for invasive alien
plants, Guidelines on Pest Risk Analysis, EPPO Bulletin 42: 463–474.
604 E. Branquart et al.
ª2016 The Authors. Journal compilation ª2016 OEPP/EPPO, EPPO Bulletin 46, 603–617
YES
Decision scheme for the prioritization process for EU invasive alien plants incorporating the
requirements of the Regulation No 1143/2014
Stage 1: Preliminary risk assessment
NO
The plant does not
qualif y
(residual list)
LOW
LOW
MEDIUM HIGH
MEDIUM
HIGH
EU LIST OF
MINO R
CONCERN
EU LIST OF
MINO R
CONCERN
EU LIST OF
MINO R
CONCERN
EU LIST OF
MINO R
CONCERN
EU
OBSERVATION
LIST
EU
OBSERVATION
LIST
EU
OBSERVATION
LIST
EU LIST OF
INVASIVE ALIEN
PLANTS
EU LIST OF
INVASIVE ALIEN
PLANTS
A.7. How high is the spread potential of the plant
species in the area under assessment?
A.2. Is the plant species known to be alien to the entire
European Union (excluding the outermost regions)?
A.1. Is the taxonomic identity of the plant species clearly
defin ed?
A.5. Is t he plant species known
to be invasive outside the
European Union?
A.6. Based on ecoclimatic
condi tions, could th e species
establish in at least 3 EU
Member States (excluding the
outermo st regions )?
A.8. H ow high is th e potential ne gative
impact of the alien plant species on native
species in the EU?
A.9. H ow high is th e potential ne gative
impac t of the alien pla nt species on
ecosy stem fu nctions and rel ated
ecosy stem se rvices in the EU?
B.4. Can the risk of introduction and spread into and within the EU be
effectively controlled by other preventive actions?
B.2. Is the plant widely cultivated or planted (over several decades) without
showin g any strong sig ns of invasiv e behaviour in the EU?
B.3. Can the risk of introduction and spread into and within the EU be
effect ively contr olled by trade res triction?
B.1. Does the plant still have a significant area for further spread and
establishment in the EU?
B.5. C an population s of the plant spec ies be eradic ated in the fie ld (at an
early stage of i nvasion ) at a reasonab le cost?
Stage 2: Risk management
List of invasive alien plants
not a priority for EU level
RA
(apply national measures)
A.3. Is t he quality and q uantity of av ailable inform ation
sufficient to assess the potential for introduction,
establishment, spread and negative impacts of the plant
in the EU?
YES
A.4. Is the plant species established in the EU (excluding
the outermost regions)?
YES
Yes, list the countries
Describe the
enda ngered
area
YES
NO
YES
NO
List of invasive alien plants
not a priority for EU level
RA
(apply national measures)
Negative impacts on
biodiversity
YES
NO
NO
NO
NO
YES
YES
YES
NO
NO
List of priority invasive
alien pl ants for EU
level RA
NO
YES
NO
The highest score from A8 and A9
should be taken into consideration
Go to Stage 2
Fig. 1 Decision scheme summarizing the prioritization process for EU invasive alien plant species incorporating the requirements of Regulation (EU)
no. 1143/2014.
A prioritization process for EU invasive alien plant species 605
ª2016 The Authors. Journal compilation ª2016 OEPP/EPPO, EPPO Bulletin 46, 603–617
biodiversity and associated ecosystem services after
establishment and spread within EU territory. This list
may include species that are already invasive within the
EU, or species which are not yet present but likely to
show invasive tendencies following their introduction.
Most of the species may only establish in some of the
biogeographical regions of Europe as defined by the
European Environment Agency.
•The EU Observation List of Invasive Alien Plants con-
tains species that are likely to cause only a moderate
detrimental impact on biodiversity and associated ecosys-
tem services and species for which additional information
is needed to determine their invasive behaviour, either
now or in the future. These species may become of con-
cern if a shift in invasion behaviour occurs and if/when
knowledge improves based on new information. Careful
surveillance and field studies are advised to improve
knowledge about these species. Early eradication actions
may also be undertaken on a voluntary basis.
•The EU List of Minor Concern includes species associ-
ated with a very low environmental risk due to a limited
capacity for spread and/or the low impacts they cause to
biodiversity and/or the associated ecosystem services.
•A Residual List of species that do not qualify, and are
therefore not included in any of the previous lists. This
could be for various reasons, such as incorrect use of the
botanical nomenclature, and can occur when a long list of
species is assessed without a preliminary screening of the
correct taxonomy; synonymy and nomenclature for all the
taxa in the list (e.g. Question A1). The residual list also
includes those species that will not pass the filters of
Questions A2 (alien status), A3 (available information),
A5 (invasive status) and A6 (potential establishment). If
additional information is published that further clarifies
the answers to the aforementioned questions, the species
may be re-prioritized.
Only species from the EU List of Invasive Alien Plants
should proceed to Stage 2 of the process. This stage
addresses risk management questions designed to define
whether actions can be taken to effectively prevent, mini-
mize or mitigate their adverse impacts. This may only be
the case when alien plant species are moved from country
to country, primarily by human activities (intentional or
unintentional), and still have a significant area suitable for
further spread within the EU. Two outcomes are possible
from Stage 2:
•The plant species is included in a List of Priority Invasive
Alien Plants for an EU-level RA: this includes invasive
alien plant species against which a concerted action at
EU level is likely to effectively prevent, minimize or mit-
igate their adverse environmental impact. In this case, a
RA should be performed according to minimum
standards.
•The alien plant species is included in a List of Invasive
Alien Plants that are not considered as a priority for an
EU-level RA; this includes invasive alien plants where no
effective action can be undertaken at EU level, either
because they are already very widespread or because no
action can be undertaken to effectively reduce their
spread and their adverse impacts through pathway man-
agement or early eradication actions. In this case, con-
ducting a detailed RA is a poor use of resources. In some
cases, national measures should be recommended.
For each species a prioritization report can be generated
from the information gathered during the process. The
information collected would be detailed under the headings
of the sections and specific questions. Key databases and
information depositories used in the collection of informa-
tion can be tabulated for the output of a prioritization report
(for an example see Gordon et al., 2010). The prioritiza-
tion Scheme will be made available in an electronic version
through the CAPRA software via the website http://
www.iap-risk.eu.
Guidance notes for Questions A1–A9 (preliminary RA
section)
A.1: Is the taxonomic identity of the plant species clearly
defined?
Having a clear understanding of the taxonomic identity of a
species is an essential component in any prioritization and
subsequent RA to ensure that the RA is performed on a dis-
tinct organism but also to ensure that information used in
the RA is relevant to the organism under consideration.
Without a clear understanding of taxonomy, problems can
arise as impacts could potentially be reported for the plant
under assessment when in reality they are caused by other
taxa. Examples of current taxonomic uncertainty include
the invasive purple-flowered alien rhododendrons in the
British Isles, usually referred to as Rhododendron
ponticum, which in most cases belong to a human-made
hybrid swarm. In addition to the R. ponticum plants intro-
duced from the Iberian Peninsula there are three North
American species involved. The plants should better be
referred to as Rhododendron 9superponticum Cullen (Cul-
len, 2011). The taxonomic concept of naturalized and
Table 1. Matrix indicating uncertainty ratings
Species absent from the EU Newcomer to the EU (limited distribution) Species widespread in the EU
Uncertainty Medium uncertainty Medium uncertainty Low uncertainty
+lack of data High uncertainty High uncertainty Medium uncertainty
+conflicting data High uncertainty High uncertainty Medium uncertainty
606 E. Branquart et al.
ª2016 The Authors. Journal compilation ª2016 OEPP/EPPO, EPPO Bulletin 46, 603–617
casual blue-flowering lupin is treated differently in various
flora of North-Western Europe. In the flora of the British
Isles (Stace, 2010), Lupinus polyphyllus Lindl. is used for
plants bearing unbranched inflorescences with blue flowers
and the naturalized plants with mostly branched inflores-
cences with blue, pink, purple or white flowers are referred
to as Lupinus 9regalis Bergmans (a hybrid of L. poly
phyllus and Lupinus arboreus Sims). Lupinus arboreus,
commonly known as Russell hybrid, is the garden lupin as
commercially available at present that has succeeded
L. polyphyllus since the 1940s. In the Flora of the Nether-
lands L. polyphyllus is inclusive of the Russell hybrids.
Whereas in the British Isles the naturalized and casual
plants largely belong to L.9regalis and any backcrosses,
in Scandinavia it is L. polyphyllus that predominates (Stace
& Crawley, 2015; Stace et al., 2015).
•If yes: go to A.2.
•If no: the plant does not qualify for further analyses. The
species is included in the residual list.
A.2: Is the plant species known to be alien to the entire EU
(excluding the outermost regions)? [Article 4.3(a)]
In the case of the EU, the area under assessment is large
and is composed of different biogeographical regions; a
species that has a native range overlapping part of the EU
territory (e.g. Pinus mugo or Acer pseudoplatanus) does not
qualify for further assessment. Species native only to the
European outermost regions (including the Azores, Canary
Islands and Madeira) are considered as alien plants to the
EU and qualify for further assessment.
•If yes: go to A.3.
•If no: the plant does not qualify as an alien plant species
to the EU. The species is included in the residual list.
A.3: Is the quality and quantity of available information
sufficient to assess the potential for introduction, establish-
ment, spread and negative impacts of the plant in the EU?
[Articles 4.3, 4.4 and 5]
Consider here the availability of information from scientific
publications and international invasive alien species data-
bases (the EPPO Global Database, CABI Invasive Species
Compendium, IUCN Global Invasive Species Database,
etc.). Species for which invasiveness is poorly documented
in the scientific literature cannot be assessed properly and
do not qualify for RA.
•If yes: go to A.4.
•If no: the plant cannot be assigned to a list based on the
current information and does not qualify as a priority for
RA. The species is included in the residual list.
A.4: Is the plant species established in the EU (excluding
the outermost regions)?
•If yes: describe the area where the species is established,
and the area of potential establishment, considering major
factors such as climatic conditions and soil types. The
world hardiness zones map (Magarey et al., 2008), the
world K€
oppen–Geiger climate classification map (Kottek
et al., 2006) and the map of the biogeographical regions
of Europe (European Environment Agency, 2016) can be
used to compare the areas where the species is recorded
and the area under assessment. Go to the assessment of
spread and impacts (Questions A.7–A.9).
•If no: the plant has never been observed in the wild in
the area under assessment, or is recorded only as casual
and may be in the process of establishment. Go to A.5.
Invasive behaviour outside the EU territory
A.5: Is the plant species known to be invasive outside the
EU?
As the species is not established in the EU, it is only possi-
ble to retrieve information from its behaviour elsewhere
(potential to spread easily in the environment and to affect
native biodiversity and related ecosystem services). The
fact that the species is reported as invasive elsewhere, at
least in regions having similar ecological and climatic con-
ditions, is considered one of the most relevant criteria in
predicting the invasive behaviour of a species (e.g.
Williamson, 1996; Kumschick & Richardson, 2013).
•If yes: go to A.6.
•If no: the plant does not qualify as a priority for RA. The
species is included in the residual list.
Assessment of establishment
A.6: Based on ecoclimatic conditions, could the plant spe-
cies establish in at least 3 EU Member States (excluding
the outermost regions)? [Article 4.3(b)]
Aquatic plants might be less susceptible to climatic condi-
tions than terrestrial plants, and this element should be taken
into account when answering this question. The world hardi-
ness zones map (Magarey et al., 2008), the world K€
oppen–
Geiger climate classification map (Kottek et al., 2006) and
the map of the biogeographical regions of Europe (European
Environmental Agency, 2016) can be used to compare the
areas where the species is recorded and the area under assess-
ment. For example, the tropical plant Psidium cattleianum
(Myrtaceae) is unlikely to establish in almost all parts of the
EU (excluding the outermost regions).
•If yes: describe the area of potential establishment consid-
ering major factors such as climatic and soil conditions,
go to assessment of spread and impacts. Go to Questions
A.7–A.9.
•If no: explain why the species is not likely to establish.
The plant does not qualify as a priority for RA. The
species is included in the residual list.
Assessment of spread and impacts
Questions A.7 to A.9 all have to be assessed independently.
The risk should be considered for the area where the spe-
cies is able to establish and cause damage within the EU,
A prioritization process for EU invasive alien plant species 607
ª2016 The Authors. Journal compilation ª2016 OEPP/EPPO, EPPO Bulletin 46, 603–617
taking into account the worst-case scenario. The risk should
not be downgraded by making an average for the entire EU
territory, if it is different from the area of potential
establishment.
As far as possible, evidence should be obtained from
records of invasive behaviour in Europe. Information on
invasive behaviour elsewhere may also provide guidance. It
is important to ensure that suitable habitats are present in
the EU; for instance, mangroves are not found within the
territory of the EU and a species requiring this habitat
would not establish.
A.7: How high is the spread potential of the plant species
in the area under assessment? [Article 4.3(b)]
This section addresses the potential of an organism to
spread to unintended habitats by natural means (water,
birds, wind, etc.) or by unintentional human assistance
(movement of soil, discarded aquarium plants, machinery,
etc.) via seeds, plant fragments or any other propagules able
to regenerate a plant. Intentional introduction is not taken
into consideration here in order to focus on the intrinsic
spread capacity of the species.
•Low: the plant does not spread because of poor dispersal
capacity (e.g. gravity dispersal) and a low reproductive
potential. Propagules are rarely found over distances
exceeding a few metres from the mother plant. For exam-
ple, Aloe vera and Agave americana reproduce vegeta-
tively only at a slow rate and rarely produce seeds. Go to
the assessment of impacts.
•Medium: the plant reproduces vigorously vegetatively
and/or sexually and spreads mainly in the vicinity of the
mother plant; dispersion capacity in the environment
rarely exceeds 100–200 m from the mother plant. For
example, Lysichiton americanus produces many seeds but
most of them fall to the ground with the faded spadix
and therefore germinate directly next to the mother plant.
Occasionally seeds may be carried greater distances by
water or animals, e.g. in mud adhering to feet. Examples
of medium spread include species spread by ants or dis-
persed by wind but with diaspores lacking specific adap-
tation to long-distance dispersal like small seeds of
Rhododendron ponticum or seed pots of Robinia
pseudoacacia that are dispersed over distances of maxi-
mum 50–100 m (Stephenson et al., 2007; Morimoto
et al., 2010; Harris et al., 2011). Unintentional dispersal
by humans is infrequent. Go to the assessment of
impacts.
•High: the plant is highly fecund and is regularly observed
to spread over distances >500–1000 m from the maternal
plant, either:
○by water: especially species invading riparian habi-
tats that have diaspores with high buoyancy. This
includes fruits, seeds or fragments of aquatic or
riparian herbaceous plants such as Heracleum
mantegazzianum, and Ludwigia spp., but also primar-
ily wind-dispersed ornamental trees such as Acer
negundo,Ailanthus altissima and Fraxinus
pennsylvanica (S€
aumel & Kowarik, 2010);
○by wind: especially species with light seeds and/or
seeds with special adaptations to long-distance dis-
persal such as wings and pappus. For example,
Cortaderia selloana produces thousands of seeds that
are wind-dispersed over long distances;
○by animals: especially species with edible fruits dis-
persed by birds and other highly mobile animals. For
example, seeds of Opuntia ficus-indica and Prunus
serotina are dispersed by birds feeding on fruits
(Deckers et al., 2005; Pairon et al., 2006);
○unintentional spread by human activities: by move-
ment of soils, or dispersal by farm machinery or by
vehicular traffic. For example, Ambrosia
artemisiifolia is dispersed along roads by vehicles
and by machines used to mow road verges; rhizomes
of Reynoutria spp. are often dispersed with soil
movements.
Uncertainty rating: low, medium, high
A.8: How high is the potential negative impact of the alien
plant species on native species in the EU? [Article 4.3(c)]
This addresses the potential for an alien plant to induce
long-term population loss of rare and threatened native
plant species through competition and hybridization
mechanisms.
The potential to displace native species by competitive
interactions (including allelopathy, competition for pollina-
tors, etc.) is unfortunately difficult to demonstrate and is
rarely documented in the scientific literature, especially at
the beginning of the invasion process. However, it could be
estimated by considering the species’ ability to form large,
dense (cover >80%) and persistent (duration >10 years)
populations, as already proposed by Brunel & Tison
(2005), Branquart (2007) and Kenis et al. (2012).
Negative environmental impacts of alien plants are
indeed typically density-dependent (Richardson et al., 1989,
2000; B
ımov
aet al., 2004; Staska et al., 2014; Fried &
Panetta, 2016); the formation of dense populations occurs
more with perennial than annual plants, especially tall
perennials (Hejda et al., 2009). There are, however, excep-
tions for alien species hybridizing with native species,
which may pose a high risk even at low densities (Daehler
& Strong, 1997; Huxel, 1999; Wolf et al., 2001). The nega-
tive impacts of alien plants are exacerbated by the long per-
sistence of the large populations they form, which typically
last for more than 10 years (Yurkonis et al., 2005) and
may even exceed 30 years as recorded for
H. mantegazzianum in the Czech Republic (Dostal et al.,
2013) and R. pseudoacacia in Germany (Cierjacks et al.,
2013). Persistence of clonal species like Cornus sericea,
Rhus typhina or Spiraea alba is known to be very long and
to strongly inhibit natural plant successions (Meilleur et al.,
1994).
608 E. Branquart et al.
ª2016 The Authors. Journal compilation ª2016 OEPP/EPPO, EPPO Bulletin 46, 603–617
The formation of large, dense and persistent populations
may occur in habitats of value for nature conservation,
where rare or threatened species are likely to occur, and in
areas of high endemism density (e.g. islands). The natural
habitats of EU importance in which the species may have
negative impacts on native species should be listed accord-
ing to the current version of Annex I of the Council Direc-
tive 92/43/EEC of 21 May 1992 on the conservation of
natural habitats and of wild fauna and flora (Habitats
Directive).
•Low: the plant does not form dense, persistent popula-
tions and rarely colonizes habitats that have a value for
nature conservation. For example, the ornamental plant
Amaranthus caudatus can escape and colonize urban
areas, cemeteries or river banks without forming dense
populations in France (Antonetti et al., 2006); the orna-
mental Datura wrightii can also escape in ruderal areas,
roadsides and waste dumps in Corsica (France) (Jean-
monod & Gamisans, 2007); Nicandra physaloides escapes
gardens and is sometimes found on roadsides and along
river beds in France (Antonetti et al., 2006).
•Medium: the plant forms large, dense, persistent popula-
tions only in habitats modified by human activities and/or
occurs in habitats that have value for nature conservation,
but does not form large, dense, persistent populations.
For example, Ambrosia artemisiiflora and Bidens
subalternans form dense, monospecific stands along road-
sides, in fallow lands and in crops, but are rarely found
to have detectable impacts in semi-natural or natural
habitats in France (Fried, 2012); in Western Europe,
Veronica persica is abundant only in cultivated fields
(Lambinon et al., 2004; Verloove, 2006; Fried, 2010);
Amelanchier lamarckii is found in some habitats of high
conservation value without forming dense populations
(Muller, 2004; Branquart et al., 2010a,b); Juncus tenuis
is also typically found along wet forest roads and the
edges of gravel ponds (Lambinon et al., 2004; Rivi
ere,
2007) but is usually at low densities when found in valu-
able and vulnerable natural communities (Verloove,
2012).
•High: the plant is reported to colonize habitats that have
a value for nature conservation where it forms large,
dense and persistent populations. For example Crassula
helmsii,Eichhornia crassipes and Ludwigia grandiflora in
water bodies in the United Kingdom, Spain and France,
respectively (Langdon et al., 2004; Muller, 2004; Ruiz
T
ellez et al., 2008); Baccharis halimifolia in coastal wet-
lands and saltmarshes in Southern Europe (Ca~
no et al.,
2013; Fried & Panetta, 2016), Carpobrotus spp. in dune
ecosystems in the Mediterranean and Atlantic parts of
France (Fried et al., 2014); and Rosa rugosa in dune
ecosystems in the Atlantic and boreal regions (Kollmann
et al., 2007; Isermann, 2008).
Alien plant species that may easily produce fertile
hybrids with native congeneric species may pose a signifi-
cant risk to the survival of these plant species by
assimilation or introgression, even if they do not form
dense populations. These types of species should be consid-
ered in this category. Examples include Spartina
alterniflora 9Spartina foliosa in salt marshes of San Fran-
cisco Bay (Daehler & Strong, 1997); Hyacinthoides
hispanica 9Hyacinthoides non-scripta in woodlands and
semi-natural grasslands of Scotland (Kohn et al., 2009);
Populus 9canadensis threatening Populus nigra in flood-
plains of Central Europe (Bleeker et al., 2007; Smulders
et al., 2008).
Uncertainty rating: low, medium, high
A.9: How high is the potential negative impact of the alien
plant species on ecosystem functions and related ecosystem
services in the EU? [Article 4.3(c)]
This addresses the potential for an alien plant to signifi-
cantly and persistently alter ecosystem functions and related
ecosystem services in natural and semi-natural habitats as
defined in The Economics of Ecosystems and Biodiversity
(TEEB) classification (see http://www.teebweb.org). Func-
tions and services that may be disrupted include: (i) provi-
sioning processes (e.g. biomass, food and water
production), (ii) regulating processes (e.g. erosion preven-
tion, alteration of soil fertility, regulation of water flow,
pollination, pest control, food web dynamics, etc.), (iii)
habitat or supporting services (e.g. food and shelter for
native plants and animals), and (iv) cultural services,
including landscape and recreation values.
List ecosystem functions and related ecosystem services
that are altered by the alien plant species in natural and
semi-natural habitats.
•Low: the plant is not reported to significantly and persis-
tently affect ecosystem functions, including losses to
related ecosystem services. For example, despite a contin-
uous influx as a contaminant of aquatic plant imports
from South-East Asia, it is unlikely that the frost-sensi-
tive alien duckweed (Landoltia punctata) will become a
nuisance weed in The Netherlands, similar to the range of
duckweed species already present in there (van Valken-
burg & Pot, 2008).
•Medium: the plant is reported to significantly and persis-
tently affect ecosystem functions, including losses to
related ecosystem services, only in habitats modified by
human activities. Ambrosia artemisiifolia is reported to
compete strongly with crop plants for water and nutrients
and to affect provisioning services of agricultural ecosys-
tems in Southern and Central Europe, but rarely behaves
in the same way in natural habitats (Muller, 2004).
•High: the plant is reported to significantly and persistently
alter ecosystem functions, including losses to related
ecosystem services, in habitats that have a value for nat-
ure conservation. Species that can significantly alter soil
conditions should be considered here, for example nitro-
gen-fixing species that increase nitrogen content in olig-
otrophic soils such as R. pseudoacacia (Rice et al.,
A prioritization process for EU invasive alien plant species 609
ª2016 The Authors. Journal compilation ª2016 OEPP/EPPO, EPPO Bulletin 46, 603–617
2004), Acacia spp. (Marchante et al., 2008) and
L. polyphyllus sensu lato (Fremstad, 2006); as well as
species modifying soil pH, nutrient availability organic
matter dynamics and/or soil communities due, for exam-
ple, to low decomposition rate, such as Carpobrotus spp.
(Conser & Connor, 2009) or Quercus rubra (Kohyt &
Skubala, 2013; Bonifacio et al., 2015).
Uncertainty rating: low, medium, high
Responses to questions on impacts (A.8 and A.9) should be
reported in the matrix in Fig. 2 in order to categorize the spe-
cies. Only the highest impact score should be considered.
Those species that have both a high negative impact
(either on native species or on ecosystem functions and
related services) and a medium or a high spread potential
are included in the EU List of Invasive Alien Plants. Spe-
cies with a medium impact and a medium or a high spread
potential are included in the EU Observation List of Inva-
sive Alien Plants, as are those that have both a high detri-
mental impact and a low spread capacity. Species with a
low impact are registered on the EU List of Minor Con-
cern, as are those that have both a medium impact and a
low spread capacity.
The overall uncertainty for Stage 1 of the prioritization
process should be summarized.
Overall uncertainty rating: low, medium, high
The species included in the EU List of Invasive Alien
Plants are those qualifying for the second stage of the
process, i.e. the risk management section.
Guidance note for questions B1–B5 (risk management
section)
B.1: Does the plant species still have a significant area for
further spread and establishment in the EU? [Articles 4.3
(d), 4.3(e) and 4.6]
Consider the extent to which the species has colonized its
potential distribution area in the EU (i.e. all suitable
habitats in the areas where ecological factors favour its
establishment) and plant frequency and density therein.
It is considered that a significant area is available for fur-
ther spread and establishment when extensive territories
suitable for plant establishment are not yet invaded or are
poorly invaded and may be colonized in the absence of
appropriate action, as it is the case for B. halimifolia,
L. americanus,Polygonum perfoliatum or Pueraria
montana within the EU. On the contrary, R. japonica and
I. glandulifera are examples of plant species that occupy
their current potential distribution range in the EU and may
hardly extend it because unoccupied areas are either too
dry or too cold to allow their development (Fig. 3); they
already reach high densities in most sites suitable for their
establishment (Beerling, 1993; Willis & Hulme, 2002). In
these cases, it is unlikely that coordinated actions under-
taken at EU level will effectively prevent, minimize or
mitigate their adverse impacts at a reasonable cost.
•If yes: go to B.2.
•If no: the plant is not a priority for RA at EU level. Con-
sider national measures such as national RA for listing
IAS of Member State concern [Article 12].
B.2: Is the plant widely cultivated or planted (over several
decades) without showing any strong sign of invasive
behaviour in the EU? [Articles 4.3 and 4.6]
Consider the extent to which the species is planted, culti-
vated and used for gardening and landscaping purposes
within the EU. The following uses should be taken into
account: agriculture (bioenergy, fodder, food, windbreaks,
etc.), agroforestry, apiculture, erosion control, ornamental
purposes (parks and gardens), landscaping, soil remediation,
silviculture, etc. Species represented by a suite of different
horticultural cultivars like Buddleja davidii or Lonicera
spp. can usually be considered as widely planted in parks
and gardens.
For those species that are widely cultivated and have
been planted over several decades in the EU, consider their
establishment in the wild and their negative impacts on
native species, ecosystem functions and the related services
in the EU. If there is no data on negative impacts within
A7 - Spread potential
Low Medium High
Negative impacts (maximum
from questions A8 and A9)
Low EU List of
Minor Concern
EU List of
Minor Concern
EU List of
Minor Concern
Medium EU List of
Minor Concern
EU Observation
List of Invasive
Alien Plants
EU Observation
List of Invasive
Alien Plants
High EU Observation
List of Invasive
Alien Plants
EU List of
Invasive Alien
Plants. Go to B.
EU List of
Invasive Alien
Plants. Go to B.
Fig. 2 Classification matrix combining spread
potential and adverse impacts on native
species, ecosystem functions and related
services.
610 E. Branquart et al.
ª2016 The Authors. Journal compilation ª2016 OEPP/EPPO, EPPO Bulletin 46, 603–617
the EU, those plants are not considered as a priority for RA
because: (i) it is assumed that there is no strong evidence
to demonstrate that they may cause environmental damage
in European conditions and (ii) consequences of species
listing are likely to cause huge economic costs, especially
when extensive plantations have to be destroyed on a large
scale. This is the case for Euonymus japonicus that has
been widely planted in the form of several cultivars for
ornamental purposes for several decades and rarely estab-
lishes wild populations and shows no signs of invasiveness
in the EU, contrary to the behaviour observed in North
America.
•If yes: the plant is not a priority for RA at the EU level.
Consider national measures such as monitoring programmes
to detect plant establishment or invasion in the wild.
•If no: go to B3.
Cost-effectiveness of prevention and management
measures [Articles 4.3(d), 4.3(e) and 4.6]
A positive (‘yes’) answer has to be provided to at least one
of the three following questions (B3–B5) to consider that
the species assessed is a high priority for RA. If this is not
possible, this means that no adequate answer can be pro-
posed to effectively reduce the spread and adverse impacts
of the species.
B.3: Can the risk of introduction and spread into and
within the EU be effectively controlled by trade restric-
tions?
Trade restriction may be considered as an effective preven-
tive action when it is considered that the plant is traded and
intentionally introduced for ornamental, agricultural, silvi-
cultural or other purposes which are significant pathways of
plant introduction and spread within the EU.
Eichhornia crassipes, for example, is widely traded within
the EU as an ornamental plant often introduced into garden
ponds from which escape in the wild is still limited, mak-
ing trade limitation an effective action to prevent the risk
of further spread of the plant (EPPO PRA 08-14407; http://
www.eppo.int). A trade restriction for Senecio inaequidens
is, on the contrary, considered inadequate to prevent plant
invasion as it is rarely sold and purposely introduced while
natural dispersal by wind-dispersed achenes is assumed to
be the major pathway for plant movement (EPPO PRA
06-12954; http://www.eppo.int).
Fig. 3 Crude estimates of the climatically
suitable regions of the EU for (A) Reynoutria
japonica, (B) Impatiens glandulifera, (C)
Lysichiton americanus and (D) Polygonum
perfoliatum. Global occurrence locations
were obtained from the Global Biodiversity
Information Facility (GBIF). The authors
acknowledge that GBIF occurrence data are
not exhaustive, especially for R. japonica and
I. glandulifera. The global climate was
summarized as two principal components
analysis (PCA) axes on the 19 WorldClim
layers (Hijmans et al., 2005). Species
occurrences were plotted in this climate
space and a bivariate normal kernel density
model (Calenge, 2006) was used to estimate
‘climate envelopes’ at different percentiles.
These envelopes were then projected onto
geographical space in the EU. Shading
indicates these percentiles, with smaller
numbers indicating higher density of
occurrences. Species with regions inside the
smaller kernel density percentiles without
species occurrences (black points) may have
a significant area for further spread and
establishment in the EU.
A prioritization process for EU invasive alien plant species 611
ª2016 The Authors. Journal compilation ª2016 OEPP/EPPO, EPPO Bulletin 46, 603–617
A number of databases, websites and catalogues provide
information on plant species imported and traded within the
EU. The following list provides examples of such websites
and further examples can be found for individual countries:
http://www.ppp-index.de (Europe-wide coverage, in
German)
https://www.rhs.org.uk/ (Royal Horticultural Society, GB,
focus in English)
http://www.jardinsdugue.eu/trouver-une-plante/?foire=In-
different (in French)
http://www.aquabase.org/ (aquatic plant focus, in French)
http://www.datiopen.it/it/opendata/Registro_delle_variet_
vegetali_ortive (In Italian)
http://cpvo.europa.eu (contains information on registers
of more than 60 countries, in English)
•If yes: the plant is a high priority for RA at the EU level.
•If no: go to B4.
B.4: Can the risk of introduction and spread into and
within the EU be effectively controlled by other preventive
actions?
The species may also be imported unintentionally as a con-
taminant of consignments of grain, seeds, wool, soil as a
growing medium, etc. or as a hitchhiker on travellers or
machinery. Effective control of unintentional introduction
and spread pathways, as intended by Article 13 of the EU
Regulation, may only be conducted when plant propagules
may easily be detected within consignments. Rhizomes of
Reynoutria spp. are often spread with soil, wherein they
can be easily detected due to their bright orange section
(Environment Agency, 2010). On the contrary, the tiny
seeds (<2 mm) of Polygonum perfoliatum are difficult to
detect within imported contaminated soils or growing media
(EPPO PRA 07-13387).
•If yes: the plant assessed is a high priority for RA at the
EU level.
•If no: go to B5.
B.5: Can populations of the plant be eradicated in the field
(at an early stage of invasion) at a reasonable cost?
When pathway management is not recognized as an effec-
tive way to reduce the risk of plant introduction and
spread, as described above for S. inaequidens and
P. perfoliatum, consider the extent to which new incursions
of the species can be cost-effectively controlled through
the active surveillance of nurseries, plantation sites, natural
habitats and other sites where the species may start to
establish.
In this case, the feasibility of local eradication depends
highly on detectability of the plant in the field, the window
of opportunity for eradication and the availability of best
practices to eliminate it (i.e. management effectiveness).
The eradication of plant species of a large size, with a long
juvenile period, short-lived seeds and a limited capacity for
regrowth such as H. mantegazzianum and L. americanus,is
usually considered to be easier to achieve than that of plant
species with the opposite suite of traits (Panetta & Tim-
mins, 2004; Panetta, 2015).
•If yes: the plant assessed is a high priority for RA at the
EU level.
•If no: the plant is not a priority for RA at the EU level
and national measures should be considered. Management
actions can, for example, be undertaken locally to reduce
species abundance and slow down invasion rate.
Discussion
When faced with a large species pool of invasive or poten-
tially invasive alien plants, prioritization is an essential pre-
requisite to focus limited resources on species which inflict
high impacts, have a high rate of spread and can be cost-
effectively managed within the EU (Kumschick et al.,
2012). The prioritization process detailed in this paper is
the first tool specifically designed to prioritize alien plants
for RA on the basis of the requirements of Regulation (EU)
no. 1143/2014. It can be used for any plant species alien to
the EU, whether currently present within the territory or
absent (see Roy et al., 2015).
The first questions of Stage 1 allow species that are
unsuitable for RA to be filtered out because of taxonomic
uncertainty, lack of scientific information or other issues
that may lead to potential problems encountered when
compiling a RA report. The remaining species are after-
wards prioritized on the basis of their establishment capac-
ity, their potential to spread and their impacts. Impacts on
native species and ecosystem functions and related ecosys-
tem services are emphasized in line with Article 4.3(c) of
the Regulation. Only those species with a medium or high
potential for spread and a high impact are included within
the EU List of Invasive Alien Plants and proceed to the
second, risk management stage. Those species with a low
potential for spread or a low or medium impact are
included in the EU Observation List of Invasive Alien
Plants or the EU List of Minor Concern and should be re-
evaluated periodically if and when additional information
comes to light.
The inclusion of risk management criteria (Stage 2) in
horizon scanning for invasive species is not usually consid-
ered in other prioritization tools (e.g. Branquart, 2007;
Sandvik et al., 2013; Roy et al., 2014; but see the pre-eva-
luation scheme of Weber & Gut, 2004, and Brunel et al.,
2010). However, those criteria are explicitly integrated into
the prioritization process presented here and are in line with
the requirements of international trade-related agreements
(EFSA Scientific Committee 2012, Lopian & Stephen,
2013) that are reflected in the risk management elements
defined in Articles 4.3(d), 4.3(e) and 4.6 of the Regulation.
The output of Stage 2 is to prioritize those species which
have a high priority for a RA at the EU level or should be
considered under national measures which may involve a
trade ban, cessation of cultivation, monitoring, containment
or eradication as foreseen for the establishment of a
612 E. Branquart et al.
ª2016 The Authors. Journal compilation ª2016 OEPP/EPPO, EPPO Bulletin 46, 603–617
national list of IAS of Member State concern (Article 12 of
the Regulation). Wherever trade will be affected by
national measures, a RA will have to be conducted at the
national scale in order to select the most appropriate mea-
sures to reduce the risk to an acceptable level; those mea-
sures will have to be notified to the European Commission
in agreement with the rules of the Treaty on the Function-
ing of the European Union (TFEU).
The risk management stage has been carefully con-
structed to assess the potential of species for further spread
and establishment coupled with the evaluation of preventa-
tive and management actions. Hence, invasive alien plants
that already occupy most of their potential range within the
EU, as well as emerging invasive alien plants whose spread
cannot be efficiently limited through pathway management
or local control actions, will also be filtered out. In addi-
tion, when invasive plants are already widespread, natural
spread is likely to contribute much more to plant invasion
than dispersal by human activities, which makes pathway
management poorly effective. In this case, a trade ban may
be considered as disproportionate according to WTO agree-
ments and rules of the TFEU (Shine et al., 2008; Lopian &
Stephen, 2013).
Question B2 is included to filter out those species which
have been present within the EU as ornamentals without
showing any strong signs of invasive behaviour. For exam-
ple, Euonymus fortunei and Lonicera maackii are high-
lighted as species with a high risk to the EU within the
next 10 years (Roy et al., 2015) though both are widely
cultivated within the EU and as of now show no signs of
invasive behaviour. Although this type of species should be
generally monitored, in the absence of any invasive beha-
viour action at a national or regional level is not warranted.
The cost-effectiveness of coordinated actions in Europe
against widespread species is rather limited, as shown with
the example of Reynoutria japonica. In the UK, the total
annual cost of this species to the economy is estimated at
166 million GBP (209 million EUR) (Williams et al.,
2010) and it could cost an estimated 1.5 billion GBP (1.8
billion EUR) to eradicate the species from the country
(DEFRA, 2003). Such high control costs mean that action
will be unlikely, especially if replicated throughout all
Member States. High figures are quoted for the eradication
of Impatiens glandulifera in the UK, where the UK Envi-
ronment Agency estimated in 2003 it would cost between
150 and 300 million GBP (189–378 million EUR), to eradi-
cate the species from the UK; however, eradication is now
practically impossible (Cockel & Tanner, 2012). Often
these control costs make no provisions for restoration of
degraded areas after control, and thus costs are likely to be
significantly elevated if restoration practices are included
(Tanner & Gange, 2013).
It should be noted that figures on control costs in Europe
are often cited based on traditional control options (chemi-
cal and manual options) with little attention to classical bio-
logical control, which has been shown to be a cost-
effective management method for widespread species
(McConnachie et al., 2003; McFadyen, 2008). Although a
detailed discussion on this aspect is outside the scope of
this paper, consideration should be given to novel manage-
ment practices (including biological control) for widespread
species which are not included in the Union List.
In conclusion, the prioritization process for EU invasive
alien plant species incorporates the requirements of Regula-
tion (EU) no. 1143/2014 and has been specifically designed
within the framework of the LIFE Project (PRE FR 001)
‘Mitigating the threat of invasive alien plants to the EU
through pest risk analysis to support the Regulation 1143/
2014’. It is intended to be a simple and flexible tool which
follows a logical step-wise process. Although the process
has been designed for alien plants, the scheme could be
adapted to suit other taxonomic groups with slight modifi-
cations to the decision scheme and associated examples and
text. For example, alien animal species could be considered
by modifying the impact questions (A8 and A9) to includ-
ing predation and disease transmission impacts, amongst
others, and modifying or omitting question B2.
When considering alien plant species for the whole of
the EPPO region, or for species under the Plant Health
Regulation, the original prioritization process for invasive
alien plants (Brunel et al., 2010) remains the optimum tool.
This scheme is more conservative than the prioritization
process presented here as it focuses on plants that are
absent or poorly established in their introduced range as
requested by the definition of a quarantine pest according
to IPPC (Lopian & Stephen, 2013). The EPPO prioritization
process is also to be preferred to address socio-economic
impacts (e.g. on agriculture and forestry) of invasive alien
plants.
Acknowledgements
This research was funded in part by the European Commis-
sion, DG Environment LIFE funding under the project
LIFE15 PRE FR 001: Mitigating the threat of invasive alien
plants in the EU through pest risk analysis to support the
Regulation (EU) No 1143/2014. Authors acknowledge
Wolfgang Rabitsch, Sonia Vanderhoeven, Montserrat Vill
a
and other members of the scientific forum dedicated to this
Regulation for useful suggestions and comments.
Un processus de priorisation pour les plantes
exotiques envahissantes, int
egrant les
exigences du R
eglement UE No 1143/2014
Face
a un grand nombre d’esp
eces de plantes exotiques
envahissantes, ou potentiellement envahissantes, prioriser
est un pr
e-requis afin de concentrer des ressources limit
ees
sur les esp
eces
a forts impacts, ayant un potentiel important
de diss
emination, et pouvant ^
etre g
er
ees de facßon efficace.
Le processus de priorisation, tel que d
ecrit dans le pr
esent
article, est le premier outil permettant d’
evaluer le besoin
A prioritization process for EU invasive alien plant species 613
ª2016 The Authors. Journal compilation ª2016 OEPP/EPPO, EPPO Bulletin 46, 603–617
de r
ealiser, en priorit
e, pour une esp
ece, une
evaluation du
risque pour l’Union Europ
eenne (UE), et ce en coh
erence
avec les exigences du R
eglement UE No 1143/2014. Ce
processus de priorisation peut ^
etre appliqu
e
a toute plante
exotique au territoire de l’UE, qu’elle soit pr
esente ou non
sur ce territoire. L’objectif est de d
eterminer, lors d’une
etape pr
eliminaire, les esp
eces prioritaires pour lesquelles
une
evaluation du risque doit ^
etre conduite au niveau de
l’UE, et qui pourraient
eventuellement ^
etre propos
ees
a
l’inscription au sein de la liste des esp
eces exotiques
envahissantes pr
eoccupantes pour l’UE. L’
evaluation du
risque pr
eliminaire (
etape 1), classe les esp
eces au sein de
l’une des quatre listes (liste des plantes exotiques
envahissantes pour l’UE, liste d’observation des plantes
exotiques envahissantes pour l’UE, liste d’importance
r
eduite pour l’UE et liste r
esiduelle) sur la base de leur
capacit
e de diss
emination et de leurs impacts. Pour les
impacts, l’accent est mis sur les esp
eces autochtones, sur
les fonctions
ecosyst
emiques, ainsi que les services
ecosyst
emiques, en coh
erence avec l’article 4.3(c) du
R
eglement UE. Seulement les esp
eces class
ees dans la liste
des plantes exotiques envahissantes pour l’UE passent
ala
seconde
etape. Au cours de cette
etape sont analys
es les
risques de diss
emination et d’
etablissement, ainsi que les
mesures prophylactiques ou mesures de gestion possibles.
L’
etape 2 classe les esp
eces les plus prioritaires pour la
r
ealisation d’une
evaluation du risque au niveau de l’UE,
ou qui devraient faire l’objet de mesures nationales telles
que l’interdiction du commerce, l’arr^
et de la culture, la
surveillance, le contr^
ole, l’enrayement ou l’
eradication. Le
processus de priorisation OEPP d’origine reste n
eanmoins
l’outil optimal lorsque le processus est
ar
ealiser sur
l’ensemble de la r
egion OEPP, ou pour des esp
eces
r
eglement
ees dans le cadre phytosanitaire.
Процесс установления приоритетов в
отношении инвазивных чужеродных видов
растений,включающий требования
Регламентации ЕС N
1143/2014
При наличии большого разнообразия видов инвазивных
или потенциально инвазивных чужеродных растений,
установление приоритетов представляет собой важное
предварительное условие,позволяющее сосредоточить
ограниченные ресурсы на тех видах,которые оказывают
сильное воздействие,обладают высокой скоростью
распространения и могут подвергаться управлению с
достаточной экономической рентабельностью.Процесс
установления приоритетов,детально рассматриваемый в
статье,представляет собой первый инструмент оценки
вида при определении приоритета для оценки риска
(ОР)вЕС,специально разработанный таким образом,
чтобы включать требования Регламентации ЕС N
1143/
2014. Процесс установления приоритетов может
использоваться для любых чужеродных для
Европейского союза видов растений,независимо от
того,присутствуют ли они в настоящий момент на его
территории.Цель установления приоритетов
заключается в том,чтобы сделать предварительное
исследование,позволяющее определить,какие
конкретные виды имеют наивысший приоритет для ОР
на уровне ЕС и могут в конечном итоге быть
предложены для включения в список инвазивных
чужеродных видов,вызывающих беспокойство ЕС.
Предварительная стадия оценки риска (Стадия 1)
заносит виды в зависимости от приоритета в один из
четырех списков (Список инвазивных для ЕС
чужеродных растений,Список наблюдения ЕС,Список
незначительного беспокойства для ЕС и Остаточный
список), основанных на потенциале их распространения
в сочетании с воздействием.Воздействие на
аборигенные виды и на функции экосистем,а также на
связанные с ними услуги экосистем отмечаются особо,в
соответствии со Статьей 4.3 (c) Регламентации ЕС.
Только виды,включенные в Список инвазивных для ЕС
чужеродных растений,проходят на вторую стадию
предварительной оценки управления рисками,когда
оценке подвергается потенциал дальнейшего
распространения и акклиматизации вместе с
возможными профилактическими и управленческими
действиями.На выходе Стадии 2должны быть
выделены виды,которые имеют приоритет для ОР на
уровне ЕС или должны рассматриваться в рамках
национальных мер,которые могут включать запрет на
торговлю,прекращение возделывания,мониторинг,
борьбу,локализацию или ликвидацию.При
рассмотрении чужеродных видов растений для всего
региона ЕОКЗР или для видов согласно
Фитосанитарным регламентациям оригинальный процесс
ЕОКЗР по установлению приоритетов для инвазивных
чужеродных растений является оптимальным средством.
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