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Datasheet

Crataegus monogyna (hawthorn)

Summary

  • Last modified
  • 09 December 2011
  • Datasheet Type(s)
  • Invasive Species
  • Pest
  • Host Plant
  • Preferred Scientific Name
  • Crataegus monogyna
  • Preferred Common Name
  • hawthorn
  • Taxonomic Tree
  • Domain: Eukaryota
  •     Kingdom: Plantae
  •         Phylum: Spermatophyta
  •             Subphylum: Angiospermae
  •                 Class: Dicotyledonae
  • Summary of Invasiveness
  • C. monogyna is the common hawthorn native to most of Europe, North Africa and West Asia. This thorny bush or small tree was introduced to North America and Australasia in the 1800s, naturalizing but only in more recent years becoming an environmental...

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Pictures

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PictureTitleCaptionCopyright
Typical shrubby specimen of hawthorn on the edge of the valley of the River Warta in Poznan, Poland. Spring 1999.
TitleTree habit
CaptionTypical shrubby specimen of hawthorn on the edge of the valley of the River Warta in Poznan, Poland. Spring 1999.
CopyrightWojciech Stachnowicz
Typical shrubby specimen of hawthorn on the edge of the valley of the River Warta in Poznan, Poland. Spring 1999.
Tree habitTypical shrubby specimen of hawthorn on the edge of the valley of the River Warta in Poznan, Poland. Spring 1999. Wojciech Stachnowicz
A blossoming twig, with leaves, of hawthorn. Valley of the river Warta in Poznan, Poland. Spring 1999.
TitleFlowers
CaptionA blossoming twig, with leaves, of hawthorn. Valley of the river Warta in Poznan, Poland. Spring 1999.
CopyrightWojciech Stachnowicz
A blossoming twig, with leaves, of hawthorn. Valley of the river Warta in Poznan, Poland. Spring 1999.
FlowersA blossoming twig, with leaves, of hawthorn. Valley of the river Warta in Poznan, Poland. Spring 1999. Wojciech Stachnowicz

Identity

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Preferred Scientific Name

  • Crataegus monogyna Jacq.

Preferred Common Name

  • hawthorn

Other Scientific Names

  • Crataegus aegeica Pojark
  • Crataegus alutacea Klokov
  • Crataegus azarella Griseb.
  • Crataegus boissieri Willk.
  • Crataegus brevispina Kunze
  • Crataegus calycina Peterm. subsp. curvisepala (Lindm.) Franco
  • Crataegus calycina Peterm. subsp. calycina
  • Crataegus ceratocarpa Kossych
  • Crataegus granatensis Boiss.
  • Crataegus laciniata sensu Willk., non Ucria
  • Crataegus lasiocarpa Lange
  • Crataegus leiomonogyna Klokov
  • Crataegus lipskyi Klokov
  • Crataegus maura auct. hisp., non L.f.
  • Crataegus oxyacantha L., nom. ambig.
  • Crataegus oxyacantha L., nom. ambig. subsp. oxyacantha
  • Crataegus oxyacantha var. praecox hort. ex Loudon
  • Crataegus panachaica C.K.Schneid.
  • Crataegus popovii Chrshan.
  • Crataegus praearmata Klokov
  • Crataegus transalpina A.Kern.
  • Crataegus triloba auct., non (Poir.) Pers
  • Mespilus monogyna (Jacq.) All.
  • Mespilus oxyacantha (L.) Crantz

International Common Names

  • English: European hawthorn; May tree; May-tree; oneseed hawthorn; one-seeded hawthorn; single-seed hawthorn; whitethorn
  • Spanish: espino albar
  • French: aubépine a un style; aubépine monogyne
  • Russian: boyaryshnik odnopestnyi
  • Portuguese: pirliteiro

Local Common Names

  • Czechoslovakia (former): hloh jednosemenny
  • Germany: Eingriffeliger Weissdorn; Eingriffliger Weissdorn; Saulenweissdorn
  • Italy: biancospino; cratego monogino
  • Netherlands: eenstijlige Meidoorn
  • Poland: glog jednoszyjkowy
  • Sweden: trubbhagtorn
  • UK: common hawthorn; single-seed hawthorn
  • USA: European hawthorn; singleseed hawthorn

EPPO code

  • CSCMO (Crataegus monogyna)

Summary of Invasiveness

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C. monogyna is the common hawthorn native to most of Europe, North Africa and West Asia. This thorny bush or small tree was introduced to North America and Australasia in the 1800s, naturalizing but only in more recent years becoming an environmental weed, especially on the Pacific coast of North America and parts of Australia and New Zealand. Seed are widely dispersed by birds who prefer the fruit over that from native plants, and thickets can form that suppress native vegetation especially in natural forest but also many other habitats. It is also hybridizing with native Crataegus species in invaded areas. Further invasion and spread of this species is to be expected especially in North America, and further introduction should be prevented.

Taxonomic Tree

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  • Domain: Eukaryota
  •     Kingdom: Plantae
  •         Phylum: Spermatophyta
  •             Subphylum: Angiospermae
  •                 Class: Dicotyledonae
  •                     Order: Rosales
  •                         Family: Rosaceae
  •                             Genus: Crataegus
  •                                 Species: Crataegus monogyna

Notes on Taxonomy and Nomenclature

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The genus Crataegus, part of the Rosaceae family (subfamily Maloideae), contains over 200 species, though some taxonomists divide these further and they may be over 1000 species depending on the descriptions followed. Several varieties and forms have been proposed, and European species are described and defined by Christensen and Janjic (2006). A number of subspecies are also recorded: subsp. monogyna (Royal Botanic Garden Edinburgh, 2007) from France to southern Ukraine, subsp. aegeica (Pojark.) Franco in the eastern Aegean, subsp. azarella (Griseb.) Franco in southeastern Europe (southern and eastern Spain and Italy, also Sicily), subsp. brevispina (Kunze) Franco in Portugal, Spain and the Balearic islands, subsp. leiomonogyna (Klokov) Franco in Russia, and subsp. calycina (Peterm.) Soó and subsp. intermedia (Fuss) Jáv. (ranges not stated).

Crataegus spp. are commonly known as the hawthorns, though species-specific vernacular names may be applied to several species, such as English hawthorn and white thorn being applied to both Crataegus monogyna and Crataegus laevigata. It is also not impossible that some introduced populations will in future be attributed to C. laevigata and not C. monogyna, and also that new spontaneous hybrids will develop in introduced ranges with both exotic and native Crataegus species as parents. The ‘haw’ in hawthorn is the name of the fruit. Many species are able to freely hybridize, further increasing variability and speciation. Being a valued ornamental, horticultural selections have also been made, and there exist a large number of cultivars.

 

Description

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C. monogyna is a thorny shrub or small tree up to 10 m high though commonly 2-6 m, with smooth pale grey bark. Branches straight with stout spines on branches; leaves alternate, ovate to obovate, 1.5-3.5 cm long, 3-7-lobed, margins entire or sparingly serrate, mostly glabrous except for patches of hairs in axils of veins on the underside. Flowers white fading to pink, in clusters, petals 5, styles 1. Fruit single-seed red berries, 1.25 cm in diameter.

Plant Type

Top of pageBroadleaved
Perennial
Seed propagated
Shrub
Tree
Vegetatively propagated
Woody

Distribution

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C. monogyna is widely distributed (Meusel et al., 1965), native to most of Europe excluding its northeastern part, and to parts of the Mediterranean coast of North Africa. C. monogyna is generally regarded as lowland species, however it has been reported from Cyprus at 1525 m in altitude, Albania and Lebanon (1600 m), Macedonia (1630 m), Greece (1650 m) and Anatolia (up to 2200 m in altitude).

Distribution Table

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The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.

CountryDistributionLast ReportedOriginFirst ReportedInvasiveReferencesNotes

ASIA

ArmeniaPresent natural CABI, 2005
AzerbaijanPresent natural CABI, 2005
Georgia (Republic of)PresentNativeNot invasive natural USDA-ARS, 2007
IndiaUnconfirmed record planted CAB Abstracts
-Jammu and KashmirUnconfirmed record planted CAB Abstracts
IranPresentNativeNot invasive natural USDA-ARS, 2007
IraqPresentNativeNot invasive natural USDA-ARS, 2007
IsraelPresentNativeNot invasive natural USDA-ARS, 2007
LebanonPresentNativeNot invasive natural USDA-ARS, 2007
SyriaPresentNativeNot invasive natural USDA-ARS, 2007
TurkeyPresentNativeNot invasive natural USDA-ARS, 2007
TurkmenistanPresent natural CABI, 2005

AFRICA

AlgeriaPresentNativeNot invasive natural USDA-ARS, 2007
EgyptPresentNativeNot invasive natural USDA-ARS, 2007
MoroccoPresentNativeNot invasive natural USDA-ARS, 2007
South AfricaPresentIntroducedInvasiveReichard et al., 2001
TunisiaPresentNativeNot invasive natural USDA-ARS, 2007

NORTH AMERICA

CanadaPresent natural CABI, 2005
-British ColumbiaPresentIntroducedInvasiveUSDA-NRCS, 2007
-New BrunswickPresentIntroducedUSDA-NRCS, 2007
-Nova ScotiaPresentIntroducedUSDA-NRCS, 2007
-OntarioPresentIntroduced natural USDA-NRCS, 2007
-Prince Edward IslandPresentIntroducedUSDA-NRCS, 2007
-QuebecPresentIntroducedUSDA-NRCS, 2007
USAPresentIntroduced1800s planted CABI, 2005
-AlaskaPresentIntroducedUSDA-NRCS, 2007
-CaliforniaPresentIntroducedInvasiveUSDA-NRCS, 2007
-ConnecticutPresentIntroducedUSDA-NRCS, 2007
-DelawarePresentIntroducedUSDA-NRCS, 2007
-IllinoisPresentIntroducedUSDA-NRCS, 2007
-KentuckyPresentIntroducedUSDA-NRCS, 2007
-MainePresentIntroducedUSDA-NRCS, 2007
-MarylandPresentIntroducedUSDA-NRCS, 2007
-MassachusettsPresentIntroducedUSDA-NRCS, 2007
-MichiganPresentIntroducedUSDA-NRCS, 2007
-MontanaPresentIntroducedUSDA-NRCS, 2007
-New HampshirePresentIntroducedUSDA-NRCS, 2007
-New JerseyPresentIntroducedUSDA-NRCS, 2007
-New YorkPresentIntroducedInvasiveHunter & Mattice, 2002; USDA-NRCS, 2007
-OhioPresentIntroducedUSDA-NRCS, 2007
-OregonPresentIntroducedInvasiveUSDA-NRCS, 2007
-PennsylvaniaPresentIntroducedUSDA-NRCS, 2007
-Rhode IslandPresentIntroducedUSDA-NRCS, 2007
-UtahPresentIntroducedUSDA-NRCS, 2007
-VermontPresentIntroducedUSDA-NRCS, 2007
-WashingtonPresentIntroducedInvasive planted USDA-NRCS, 2007
-West VirginiaPresentIntroducedUSDA-NRCS, 2007
-WisconsinPresentIntroducedUSDA-NRCS, 2007

EUROPE

AlbaniaPresentNativeNot invasive natural USDA-ARS, 2007
AustriaPresentNativeNot invasive natural and planted USDA-ARS, 2007
BelarusPresent natural and planted CABI, 2005
BelgiumPresentNativeNot invasive natural and planted USDA-ARS, 2007
Bosnia-HercegovinaPresent natural CABI, 2005
BulgariaPresentNativeNot invasive natural USDA-ARS, 2007
CroatiaPresent natural CABI, 2005
CyprusPresentNativeNot invasive natural USDA-ARS, 2007
Czech RepublicPresent natural and planted CABI, 2005
Czechoslovakia (former)PresentNativeNot invasiveUSDA-ARS, 2007
DenmarkPresentNativeNot invasive natural and planted USDA-ARS, 2007
EstoniaPresent natural and planted CABI, 2005
FinlandPresentNativeNot invasive natural and planted USDA-ARS, 2007
FrancePresentNativeNot invasive natural and planted USDA-ARS, 2007
-CorsicaPresent natural CABI, 2005
GermanyPresentNativeNot invasive natural and planted USDA-ARS, 2007
GreecePresentNativeNot invasive natural USDA-ARS, 2007
HungaryPresentNativeNot invasive natural and planted USDA-ARS, 2007
IrelandPresentNativeNot invasive natural and planted USDA-ARS, 2007
ItalyPresentNativeNot invasive natural and planted USDA-ARS, 2007; CAB Abstracts
LatviaPresent natural and planted CABI, 2005
LiechtensteinPresent natural CABI, 2005
LithuaniaPresent natural and planted CABI, 2005
LuxembourgPresent natural CABI, 2005
MacedoniaPresent natural CABI, 2005
MoldovaPresent natural CABI, 2005
MonacoPresent natural CABI, 2005
NetherlandsPresentNativeNot invasive natural and planted USDA-ARS, 2007
NorwayPresentNativeNot invasive natural USDA-ARS, 2007
PolandPresentNativeNot invasive natural and planted USDA-ARS, 2007
PortugalPresentNativeNot invasive natural USDA-ARS, 2007
RomaniaPresentNativeNot invasive natural and planted USDA-ARS, 2007
Russian FederationPresentNativeNot invasive natural USDA-ARS, 2007
-Central RussiaPresentNativeNot invasiveRoyal Botanic Garden Edinburgh, 2007
-Southern RussiaPresentNativeNot invasive natural USDA-ARS, 2007
San MarinoPresent natural CABI, 2005
SerbiaPresent natural CABI, 2005
SlovakiaPresent natural and planted CABI, 2005
SloveniaPresent natural CABI, 2005
SpainPresentNativeNot invasive natural USDA-ARS, 2007
-Balearic IslandsPresent natural CABI, 2005
SwedenPresentNativeNot invasive natural USDA-ARS, 2007
SwitzerlandPresentNativeNot invasive natural and planted USDA-ARS, 2007
UKPresentNativeNot invasive natural and planted USDA-ARS, 2007
UkrainePresentNativeNot invasive natural and planted USDA-ARS, 2007
Yugoslavia (former)PresentNativeNot invasiveUSDA-ARS, 2007

OCEANIA

AustraliaPresentIntroducedInvasive natural and planted Royal Botanic Gardens Sydney, 2007
-New South WalesPresentIntroducedInvasive natural and planted Bass et al., 2006
-QueenslandPresentIntroducedRoyal Botanic Gardens Sydney, 2007
-South AustraliaPresentIntroducedRoyal Botanic Gardens Sydney, 2007
-TasmaniaPresentIntroducedRoyal Botanic Gardens Sydney, 2007
-VictoriaPresentIntroducedRoyal Botanic Gardens Sydney, 2007
New ZealandPresentIntroduced1899Invasive natural and planted Owen, 1996

History of Introduction and Spread

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It has been widely introduced, is commonly planted and has become naturalized in North America, southern Africa, Australia and New Zealand having been introduced to each sometime in the 1800s. It has been observed to be an aggressive colonizer (Bass, 1990; Williams et al., 1986), and has become an invasive species in the Pacific northwest of the USA (Oregon and Washington), also British Columbia, and it was recently noted as fully naturalized and a potential pest in northern California, USA (Hrusa et al., 2002). It is also one of six woody invasive species in New York, USA, by Hunter and Mattice (2002), and noting its widespread distribution in North America (USDA-NRCS, 2007), further invasion in other states and provinces is highly likely. C. monogyna is also invasive in South Africa, where birds are aiding spread in the Eastern Cape (Reichard et al., 2001). It is very invasive in northern New South Wales, having spread rapidly and conspicuously throughout the region and elsewhere in southern Australia at rates of 80–120 m yr-1 (Bass et al., 2006), and it is an environmental weed of concern in New Zealand, having been introduced in 1899 (Owen, 1996).

Risk of Introduction

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It is a noted weed in all countries where it is spreading. It is on California’s CalEPPC Red Alert list, and is expected to be declared noxious in other states and countries. Existing stands should be monitored, and further introduction via the horticultural trade should be prevented.

Habitat

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C. monogyna is found in lowland areas on many soils, and is often considered principally a forest understory species in its native range, though it also prefers moist to damp disturbed places such as wetlands and lake margins as well as and open forests. It appears to thrive best in deeper soils. Throughout its range C. monogyna grows in several types of open forests and thickets, and in Central Europe, it forms its own plant community Pruno-Crataegetum, being a successional stage of vegetation leading to natural oak-hornbeam forests (Querco-Carpinetum sensu lato) (Wojterska, 1990).

In North America, riparian areas, abandoned fields and pastures, oak woodlands, and other forested habitats must be considered as potential habitat although outlying plants can be found in shrubland or grassland, especially near the coast (Alverson and Sigg, 2008).

Habitat List

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CategoryHabitatPresenceStatus
Littoral
Coastal areasPresent, no further detailsHarmful (pest or invasive)
Coastal areasPresent, no further detailsNatural
Terrestrial-managed
Cultivated / agricultural landPresent, no further detailsHarmful (pest or invasive)
Cultivated / agricultural landPresent, no further detailsNatural
Cultivated / agricultural landPresent, no further detailsProductive/non-natural
Disturbed areasPresent, no further detailsHarmful (pest or invasive)
Disturbed areasPresent, no further detailsNatural
Managed forests, plantations and orchardsPresent, no further detailsHarmful (pest or invasive)
Managed grasslands (grazing systems)Present, no further detailsHarmful (pest or invasive)
Managed grasslands (grazing systems)Present, no further detailsNatural
Managed grasslands (grazing systems)Present, no further detailsProductive/non-natural
Rail / roadsidesPresent, no further detailsHarmful (pest or invasive)
Rail / roadsidesPresent, no further detailsNatural
Rail / roadsidesPresent, no further detailsProductive/non-natural
Urban / peri-urban areasPresent, no further detailsProductive/non-natural
Terrestrial-natural/semi-natural
Natural forestsPresent, no further detailsHarmful (pest or invasive)
Natural forestsPresent, no further detailsNatural
Natural grasslandsPresent, no further detailsHarmful (pest or invasive)
Natural grasslandsPresent, no further detailsNatural
RiverbanksPresent, no further detailsHarmful (pest or invasive)
RiverbanksPresent, no further detailsNatural
Scrub / shrublandsPresent, no further detailsHarmful (pest or invasive)
Scrub / shrublandsPresent, no further detailsNatural
WetlandsPresent, no further detailsHarmful (pest or invasive)
WetlandsPresent, no further detailsNatural

Biology and Ecology

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Genetics

It is an exceptionally variable species in all its morphological features, particularly in size and shape of leaves, resulting in a high number of forms described from various parts of its range (Browicz, 1986). Hybridization is also likely to have played a significant role is this variation.
 
Reproductive Biology
 
C. monogyna is pollinated mainly by honey bees (Apis spp.). In Europe, fruit mature in the autumn, and can stay on the tree until mid-winter. At one site in western Oregon, the fruit crop was estimated at 2,721 fruits per plant. Seed longevity is unknown. Seed germination is aided by passing through a bird’s digestive tract, but this is not necessary for germination (Alverson and Sigg, 2008).
 
Physiology and Phenology
 
C. monogyna is described variously as a light demanding species or one showing tolerance of shade. After seed germination, in spring, C. monogyna grows rapidly for the first 15 years, and can live up to 250 years. Most vegetative growth occurs in spring and early summer, and growth rates are around 30-60 cm per year. After winter dormancy, leaves appear in March or April in the northern hemisphere, with flowers appearing after the leaves, and the fruit ripens in late autumn. It can, however, also spread vegetatively, suckering from its long, spreading roots when the main stem is cut.
 
Environmental Requirements

C. monogyna grows best in humid and sub-humid temperate zones, though is also native to cold climates in Scandinavia and is introduced in Canada and Alaska, USA. Once established, C. monogyna can withstand moderate drought.

Climate

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ClimateStatusDescriptionRemark
C - Temperate/Mesothermal climatePreferredAverage temp. of coldest month > 0°C and < 18°C, mean warmest month > 10°C
Cf - Warm temperate climate, wet all yearPreferredWarm average temp. > 10°C, Cold average temp. > 0°C, wet all year
Cs - Warm temperate climate with dry summerPreferredWarm average temp. > 10°C, Cold average temp. > 0°C, dry summers
Cw - Warm temperate climate with dry winterPreferredWarm temperate climate with dry winter (Warm average temp. > 10°C, Cold average temp. > 0°C, dry winters)
D - Continental/Microthermal climateToleratedContinental/Microthermal climate (Average temp. of coldest month < 0°C, mean warmest month > 10°C)
Df - Continental climate, wet all yearToleratedContinental climate, wet all year (Warm average temp. > 10°C, coldest month < 0°C, wet all year)
Ds - Continental climate with dry summerToleratedContinental climate with dry summer (Warm average temp. > 10°C, coldest month < 0°C, dry summers)
Dw - Continental climate with dry winterToleratedContinental climate with dry winter (Warm average temp. > 10°C, coldest month < 0°C, dry winters)

Latitude/Altitude

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Latitude North (°N)Latitude South (°S)Altitude Lower (m)Altitude Upper (m)
643102200

Air Temperature

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ParameterLower limitUpper limit
Absolute minimum temperature (ºC)-35
Mean annual temperature (ºC)519
Mean maximum temperature of hottest month (ºC)1728
Mean minimum temperature of coldest month (ºC)-109

Rainfall

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ParameterLower limitUpper limitDescription
Dry season duration07number of consecutive months with <40 mm rainfall
Mean annual rainfall4001050mm; lower/upper limits

Rain Regime

Top of pageBimodal
Summer
Uniform
Winter

Soil Tolerances

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Soil drainage

  • free

Soil reaction

  • acid
  • neutral

Soil texture

  • heavy
  • medium

Special soil tolerances

  • infertile
  • shallow

Notes on Natural Enemies

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There are relatively few pests and pathogens of C. monogyna. The most important disease is ‘fire blight’ caused by the bacteria Erwinia amylovora, and it should never be planted in the neighbourhood of orchards as it acts as an alternative hosts for this, one of the most dangerous disease of fruit-trees of the family Rosaceae (Zajaczkowski, 1998). In Australia, plants are severely attacked by the pear and cherry slug (Caliroa cerasi) in some years, which damages the foliage though this does not appear to harm the tree itself.

Means of Movement and Dispersal

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Natural Dispersal (Non-Biotic)
 
Berries could roll down slopes and be spread by rivers and/or floodwaters, but this is not considered as significant as compared to birds and other animals in seed dispersal.
 
Vector Transmission (Biotic)
 
The fleshy, edible fruits are eaten by animals which disperse the seeds, and C. monogyna has seeds dispersed by birds and mammals over many kilometres (Bass et al., 2006), this being the principle means of dissemination. Reichard et al. (2001) observed seed dispersal of C. monogyna by the pied currawong (Strepera graculina) in New South Wales, Australia, and by the American robin (Turdus migratorius) in South Africa, noting that the large are more frequently found fruit was generally preferred over that of native plants. In the native range, rodents are also observed to act as dispersal agents (Garcia-Castano et al., 2006), as were blackbirds (Turdus merula) and a species of lizard (Podarcis pityusensis) (Rodriguez-Perez et al., 2005).
 
Accidental Introduction
 
Seeds may also spread by clinging to farm machinery, vehicles, and animals or by contaminating agricultural produce (Alverson and Sigg, 2008).
 
Intentional Introduction

The principal means of long-distance dispersal has been its intentional introduction as an ornamental/landscaping and hedging/boundary plant. For these reasons, it was introduced to North America, South Africa and Australasia, and further introduction may be likely.

Pathway Causes

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CauseNotesLong DistanceLocalReferences
Digestion/excretionYesBass et al., 2006
Escape from confinement/ garden escapeYesAlverson & Sigg, 2008
Hedges/ windbreaksYesYesAlverson & Sigg, 2008
Landscape improvement/ landscaping industryYesYesAlverson & Sigg, 2008
Nursery tradeYesYesAlverson & Sigg, 2008
Ornamental purposesYesYesAlverson & Sigg, 2008

Pathway Vectors

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VectorNotesLong DistanceLocalReferences
Land vehiclesYesAlverson & Sigg, 2008
LivestockYesAlverson & Sigg, 2008
Machinery/equipmentYesAlverson & Sigg, 2008

Impact Summary

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CategoryImpact
Environment (generally)Positive and negative

Economic Impact

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There are clear positive impacts from the propagation and sale of C. monogyna and its many cultivars as ornamental plants, and also for the sale of seedlings or cuttings from commercial forestry nurseries for planting as hedges or in general landscaping. However, no exact data as to its economic contribution are forthcoming, and it may be expected that such exact figures would be difficult to estimate. Negative impacts are also increasing likely in the form of control programmes in natural areas of North America and Australasia where it is becoming a problematic invasive weed.

In addition, due it acting as a host for crop pests and pathogens or pests, it should not be planted near some crops, such as fruit trees and hops (Puszkar, 1981; Zajaczkowski, 1998).

Environmental Impact

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Hawthorn's thickets are shelters for many birds and little mammals, therefore, they are important for nature protection purposes, especially on agricultural or urbanized grounds.

However, where invasive, it displaces native plants, and dense thickets alter the structure of the forest understory and can make the movement of large animals difficult. Some species of Crataegus contain hydrocyanic acid in the leaves, which is poisonous to cattle, though the presence of this in C. monogyna is not yet known. Birds may prefer its berries to those of native berried plants, which may cause a reduction in the regeneration of native plants. Also, the ability of C. monogyna to hybridise with native species of Crataegus, means that there will be genetic pollution of the indigenous gene pool over time in invaded areas.

One nature preserve in Willamette Valley, Oregon, USA, has had to be abandoned because C. monogyna has invaded and there are not adequate resources to control it (Alverson and Sigg, 2008), and there is also a specific threat to the Garry Oak ecosystem of British Columbia, Canada.

Risk and Impact Factors

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Impact mechanisms

  • Competition - monopolizing resources
  • Competition - shading
  • Hybridization
  • Interaction with other invasive species
  • Pest and disease transmission
  • Pollen swamping

Impact outcomes

  • Changed gene pool/ selective loss of genotypes
  • Ecosystem change/ habitat alteration
  • Modification of successional patterns
  • Monoculture formation
  • Reduced native biodiversity
  • Threat to/ loss of endangered species
  • Threat to/ loss of native species

Invasiveness

  • Abundant in its native range
  • Has a broad native range
  • Has high genetic variability
  • Has high reproductive potential
  • Highly adaptable to different environments
  • Highly mobile locally
  • Long lived
  • Pioneering in disturbed areas
  • Proved invasive outside its native range
  • Reproduces asexually
  • Tolerates, or benefits from, cultivation, browsing pressure, mutilation, fire etc

Likelihood of entry/control

  • Difficult to identify/detect as a commodity contaminant
  • Difficult to identify/detect in the field
  • Highly likely to be transported internationally deliberately

Uses

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C. monogyna is often planted in hedges and shelterbelts on farms and as an ornamental shrub or small tree in towns and cities and has been successfully used in revegetation and land reclamation of wastelands and mine spoils (Kluczynski, 1981; La Marca et al., 1998) as well as on polders in Holland (Peeters and Stuurman, 1981). The species is relatively tolerant to air pollution (Hirka, 1992) and as such seems to be particularly convenient for planting along roads and motorways. The spines deter grazing animals, and the plant is regarded as an impenetrable barrier to grazing. Seeds require stratification before sowing in spring, and 1-2-year-old seedlings or cuttings are used, the latter best in gaps within old hedges.

The wood of C. monogyna is narrow-ringed, extremely hard and durable and is sometimes used for the production of various small objects. The possibility of its utilisation for other purposes is limited by its low speed of growth. The flowers and fruits of hawthorn have been used in folk medicine for a long time and are now regarded as a precious raw material in production of important drugs to combat heart disease (e.g. Iwamoto et al., 1981), hypertension and allergies. The fruits of C. monogyna contain many vitamins, and are widely collected and consumed in some rural areas where native.

Uses List

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Environmental

  • Agroforestry
  • Amenity
  • Boundary, barrier or support
  • Revegetation
  • Shade and shelter
  • Soil conservation
  • Wildlife habitat
  • Windbreak

Fuels

  • Fuelwood

General

  • Ornamental

Human food and beverage

  • Emergency (famine) food
  • Fruits
  • Honey/honey flora

Materials

  • Carved material
  • Poisonous to mammals
  • Wood/timber

Medicinal, pharmaceutical

  • Source of medicine/pharmaceutical
  • Traditional/folklore

Ornamental

  • Propagation material

Wood Products

Top of pageTool handles
Turnery
Wood carvings
Woodware

Similarities to Other Species/Conditions

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Native Crataegus on the west coast of North America can be distinguished from the introduced C. monogyna as they generally have purple-black (not red) fruit, mostly unlobed (not lobed) leaves and 5 (not 1) styles. Hybrids also have purple-black fruits but have leaves and flowers with intermediate characters, such as partially lobed leaves and flowers with 2-3 styles.

Prevention and Control

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Control

Cultural control and sanitary measures
 
Awareness-raising programmes are beginning to be put in place in western North America to educate the public and the horticultural industry about the risks posed by C. monogyna as an invasive species.
 
Physical/mechanical control
 
Small infestations of young plants can be hand pulled, preferably when the soil is moist, and taking care to minimize soil disturbance. Trees can be cut using a brush-cutter, hand saw or chainsaw as size and available equipment dictate. Regrowth will occur, however, unless the entire crown and the top few centimetres of the main roots are removed, or the stump is burnt. As for the best time to cut, there are various views. Some say in early summer. when the plant is actively growing and little is stored in the roots. Others note that cutting is probably most effective when about 20% of the flowers have gone to seed, but should not be carried out if native plants are still flowering or setting seed. Avoid cutting when the trees are full of berries as this will just aid their spread. Cut material should be taken off-site or burnt as it can regenerate from cuttings, but this will be difficult by hand due to the long, sharp thorns.
 
Movement control
 
Due to the widespread availability of C. monogyna as an ornamental and landscaping plant, attempts should be made to further restrict the movement of this plant to areas where it is not yet present.
 
Biological control
 
C. monogyna has no known effective biocontrol agents.
 
Chemical control

Larger plants can be cut to the ground and the stump treated with a 1:3 mixture of triclopyr (or glyphosate) and a light cooking oil as surfactant, and a 2-3% solution of triclopyr or glyphosate has been sprayed on the foliage for control, but this has not generally been reliable and is more likely to affect non-target species than are stump treatments (Alverson and Sigg, 2008).

References

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Bass DA, 1990. A comparative study of the invasiveness of two alien fleshy-fruiting woody plants on the Northern Tablelands of New South Wales. Proceedings of the 9th Australian Weeds Conference, 109-112

Bass DA, Crossman ND, Lawrie SL, Lethbridge MR, 2006. The importance of population growth, seed dispersal and habitat suitability in determining plant invasiveness. Euphytica, 148(1/2):97-109.

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García-Castaño JL, Kollmann J, Jordano P, 2006. Spatial variation of post-dispersal seed removal by rodents in highland microhabitats of Spain and Switzerland. Seed Science Research, 16(3):213-222. http://journals.cambridge.org/download.php?file=%2FSSR%2FSSR16_03%2FS0960258506000237a.pdf&code=40dda3597bbd3a74e4a6c55bf429b91c

Gosler AG, 1990. Introgressive hybridization between Crataegus monogyna Jacq. and C. laevigata (Poiret) DC. in the Upper Thames Valley, England. Watsonia, 18(1):49-62; 16 ref.

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Gostynska-Jakuszewska M, Hrabetova-Uhrova A, 1983. Distribution of Crataegus species in Poland and Czechoslovakia. Preslia, 55(1):9-24.

Guitian J, Fuentes M, 1992. Reproductive biology of Crataegus monogyna in northwestern Spain. Acta Oecologica, 13(1):3-11

Hirka A, 1992. Effects of severe and direct industrial immissions on a Quercus cerris stand. [Uber Wirkungen starker und direkter Industrie-Immissionen auf einen Zerreichen-Bestand (Quercus cerris L.).] Anzeiger fur Schadlingskunde, Pflanzenschutz, Umweltschutz, 65: 151-153; 3 ref.

Hrusa F, Ertter B, Sanders A, Leppig G, Dean E, 2002. Catalogue of non-native vascular plants occurring spontaneously in California beyond those addressed in The Jepson Manual - Part I. Madroño, 49(2):61-98.

Hunter JC, Mattice JA, 2002. The spread of woody exotics into the forests of a northeastern landscape, 1938-1999. Journal of the Torrey Botanical Society, 129(3):220-227.

Ilmurzynski E, 1969. Szczególowa hodowla lasu. [Silviculture in detail]. PWRiL, Warszawa.

Iwamoto M, Ishizaki T, Sato T, 1981. Clinical effects of Crataegutt on heart diseases of ischaemic and/or hypertensive origin. A multi-centre double-blind study. [Klinische Wirkung von Crataegutt bei Herzerkrankungen ischamischer und/oder hypertensiver Genese. Eine multizentrische Doppelblindstudie.] Planta Medica, 42(1):1-16.

Kluczynski B, 1981. Studies of the suitability of trees and shrubs for the revegetation of siderite mine spoils in the Czestochowa region. [Badanie przydatnosci drzew i krzewow do rekultywacji i zagospodarowania hald posyderytowych w rejonie Czestochowy.] Arboretum Kornickie, 26: 203-229.

Kobendza R, 1955. Crataegus L. Glóg. In: Szafer W, Pawlowski B, eds. Flora Polska. Rosliny naczyniowe Polski i ziem osciennych. [The Polish Flora. Vascular Plants of Poland and neighbouring territories.] Warszawa-Kraków, Poland: PWN, 7:261-269.

Kociecki S, Zdanowski A, Kolk A et al., 1991. Mala Encyklopedia Lesna. [Small Encyclopedia of Forestry.] Warszawa, Poland: PWN.

Marca Ola, Gambi L, Pignatti G, Sanesi G, 1998. Studies of the vegetation and environment on a rehabilitated domestic waste landfill site. Monti e Boschi, 49(1):13-23; 12 ref.

Meusel H, Jäger E, Weinert E, 1965. Vergleichende Chorologie der zentraleuropäischen Flora. Jena, Germany: Fischer.

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Owen SJ, 1996. Ecological weeds on conservation land in New Zealand: a database. Department of Conservation, Wellington, New Zealand: DOC Science Publications. http://www.hear.org/weedlists/other_areas/nz/nzecoweeds.htm

Peeters JP, Stuurman FJ, 1981. Ten years of woodland in the Broekpolder. [Tien jaar bos in de Broekpolder.] Groen, No.5, 229-242.

Polietitko OM, 1954. Boyaryshnik - Crataegus L. Dieriewya i kustarniki SSSR. Moskva-Leningrad, 3:514-577.

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Rodríguez-Pérez J, Riera N, Traveset A, 2005. Effect of seed passage through birds and lizards on emergence rate of mediterranean species: differences between natural and controlled conditions. Functional Ecology, 19(4):699-706. http://www.blackwell-synergy.com/servlet/useragent?func=showIssues&code=fec

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Contributors

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11/01/2008 Updated by:

Nick Pasiecznik, Consultant, France

Distribution Maps

Top of page
Distribution map Albania: Present, native, not invasive
USDA-ARS, 2007Armenia: Present
CABI, 2005Armenia: Present
CABI, 2005Austria: Present, native, not invasive
USDA-ARS, 2007Australia: Present, introduced, invasive
Royal Botanic Gardens Sydney, 2007Australia
See regional map for distribution within the countryAustralia
See regional map for distribution within the countryAustralia
See regional map for distribution within the countryAustralia
See regional map for distribution within the countryAustralia
See regional map for distribution within the countryAzerbaijan: Present
CABI, 2005Azerbaijan: Present
CABI, 2005Bosnia-Hercegovina: Present
CABI, 2005Belgium: Present, native, not invasive
USDA-ARS, 2007Bulgaria: Present, native, not invasive
USDA-ARS, 2007Belarus: Present
CABI, 2005Canada: Present
CABI, 2005Canada
See regional map for distribution within the countryCanada
See regional map for distribution within the countryCanada
See regional map for distribution within the countryCanada
See regional map for distribution within the countryCanada
See regional map for distribution within the countryCanada
See regional map for distribution within the countrySwitzerland: Present, native, not invasive
USDA-ARS, 2007Czechoslovakia (former): Present, native, not invasive
USDA-ARS, 2007Cyprus: Present, native, not invasive
USDA-ARS, 2007Cyprus: Present, native, not invasive
USDA-ARS, 2007Czech Republic: Present
CABI, 2005Germany: Present, native, not invasive
USDA-ARS, 2007Denmark: Present, native, not invasive
USDA-ARS, 2007Algeria: Present, native, not invasive
USDA-ARS, 2007Algeria: Present, native, not invasive
USDA-ARS, 2007Estonia: Present
CABI, 2005Egypt: Present, native, not invasive
USDA-ARS, 2007Spain: Present, native, not invasive
USDA-ARS, 2007Spain: Present, native, not invasive
USDA-ARS, 2007Spain
See regional map for distribution within the countryFinland: Present, native, not invasive
USDA-ARS, 2007France: Present, native, not invasive
USDA-ARS, 2007France
See regional map for distribution within the countryUK: Present, native, not invasive
USDA-ARS, 2007Georgia (Republic of): Present, native, not invasive
USDA-ARS, 2007Georgia (Republic of): Present, native, not invasive
USDA-ARS, 2007Greece: Present, native, not invasive
USDA-ARS, 2007Greece: Present, native, not invasive
USDA-ARS, 2007Croatia: Present
CABI, 2005Hungary: Present, native, not invasive
USDA-ARS, 2007Ireland: Present, native, not invasive
USDA-ARS, 2007Israel: Present, native, not invasive
USDA-ARS, 2007Israel: Present, native, not invasive
USDA-ARS, 2007India: Unconfirmed recordIndia
See regional map for distribution within the countryIraq: Present, native, not invasive
USDA-ARS, 2007Iraq: Present, native, not invasive
USDA-ARS, 2007Iraq: Present, native, not invasive
USDA-ARS, 2007Iran: Present, native, not invasive
USDA-ARS, 2007Iran: Present, native, not invasive
USDA-ARS, 2007Iran: Present, native, not invasive
USDA-ARS, 2007Italy: Present, native, not invasive
USDA-ARS, 2007Lebanon: Present, native, not invasive
USDA-ARS, 2007Lebanon: Present, native, not invasive
USDA-ARS, 2007Lebanon: Present, native, not invasive
USDA-ARS, 2007Liechtenstein: Present
CABI, 2005Lithuania: Present
CABI, 2005Luxembourg: Present
CABI, 2005Latvia: Present
CABI, 2005Morocco: Present, native, not invasive
USDA-ARS, 2007Morocco: Present, native, not invasive
USDA-ARS, 2007Monaco: Present
CABI, 2005Moldova: Present
CABI, 2005Macedonia: Present
CABI, 2005Netherlands: Present, native, not invasive
USDA-ARS, 2007Norway: Present, native, not invasive
USDA-ARS, 2007New Zealand: Present, introduced, invasive
Owen, 1996Poland: Present, native, not invasive
USDA-ARS, 2007Portugal: Present, native, not invasive
USDA-ARS, 2007Romania: Present, native, not invasive
USDA-ARS, 2007Serbia: Present
CABI, 2005Russian Federation: Present, native, not invasive
USDA-ARS, 2007Russian Federation: Present, native, not invasive
USDA-ARS, 2007Russian Federation
See regional map for distribution within the countryRussian Federation
See regional map for distribution within the countrySweden: Present, native, not invasive
USDA-ARS, 2007Slovenia: Present
CABI, 2005Slovakia: Present
CABI, 2005San Marino: Present
CABI, 2005Syria: Present, native, not invasive
USDA-ARS, 2007Syria: Present, native, not invasive
USDA-ARS, 2007Syria: Present, native, not invasive
USDA-ARS, 2007Turkmenistan: Present
CABI, 2005Tunisia: Present, native, not invasive
USDA-ARS, 2007Tunisia: Present, native, not invasive
USDA-ARS, 2007Turkey: Present, native, not invasive
USDA-ARS, 2007Turkey: Present, native, not invasive
USDA-ARS, 2007Turkey: Present, native, not invasive
USDA-ARS, 2007Ukraine: Present, native, not invasive
USDA-ARS, 2007Ukraine: Present, native, not invasive
USDA-ARS, 2007USA: Present, introduced
CABI, 2005USA: Present, introduced
CABI, 2005USA
See regional map for distribution within the countryUSA
See regional map for distribution within the countryUSA
See regional map for distribution within the countryUSA
See regional map for distribution within the countryUSA
See regional map for distribution within the countryUSA
See regional map for distribution within the countryUSA
See regional map for distribution within the countryUSA
See regional map for distribution within the countryUSA
See regional map for distribution within the countryUSA
See regional map for distribution within the countryUSA
See regional map for distribution within the countryUSA
See regional map for distribution within the countryUSA
See regional map for distribution within the countryUSA
See regional map for distribution within the countryUSA
See regional map for distribution within the countryUSA
See regional map for distribution within the countryUSA
See regional map for distribution within the countryUSA
See regional map for distribution within the countryUSA
See regional map for distribution within the countryUSA
See regional map for distribution within the countryUSA
See regional map for distribution within the countryUSA
See regional map for distribution within the countryUSA
See regional map for distribution within the countryYugoslavia (former): Present, native, not invasive
USDA-ARS, 2007South Africa: Present, introduced, invasive
Reichard et al., 2001
  • = Present, no further details
  • = Evidence of pathogen
  • = Widespread
  • = Last reported
  • = Localised
  • = Presence unconfirmed
  • = Confined and subject to quarantine
  • = See regional map for distribution within the country
  • = Occasional or few reports
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Distribution map (asia) Armenia: Present
CABI, 2005Azerbaijan: Present
CABI, 2005Georgia (Republic of): Present, native, not invasive
USDA-ARS, 2007Israel: Present, native, not invasive
USDA-ARS, 2007India: Unconfirmed recordJammu and Kashmir: Unconfirmed recordIraq: Present, native, not invasive
USDA-ARS, 2007Iran: Present, native, not invasive
USDA-ARS, 2007Lebanon: Present, native, not invasive
USDA-ARS, 2007Russian Federation: Present, native, not invasive
USDA-ARS, 2007Syria: Present, native, not invasive
USDA-ARS, 2007Turkmenistan: Present
CABI, 2005Turkey: Present, native, not invasive
USDA-ARS, 2007Ukraine: Present, native, not invasive
USDA-ARS, 2007
Distribution map (europe) Albania: Present, native, not invasive
USDA-ARS, 2007Armenia: Present
CABI, 2005Austria: Present, native, not invasive
USDA-ARS, 2007Azerbaijan: Present
CABI, 2005Bosnia-Hercegovina: Present
CABI, 2005Belgium: Present, native, not invasive
USDA-ARS, 2007Bulgaria: Present, native, not invasive
USDA-ARS, 2007Belarus: Present
CABI, 2005Switzerland: Present, native, not invasive
USDA-ARS, 2007Czechoslovakia (former): Present, native, not invasive
USDA-ARS, 2007Cyprus: Present, native, not invasive
USDA-ARS, 2007Czech Republic: Present
CABI, 2005Germany: Present, native, not invasive
USDA-ARS, 2007Denmark: Present, native, not invasive
USDA-ARS, 2007Algeria: Present, native, not invasive
USDA-ARS, 2007Estonia: Present
CABI, 2005Spain: Present, native, not invasive
USDA-ARS, 2007Balearic Islands: Present
CABI, 2005Finland: Present, native, not invasive
USDA-ARS, 2007France: Present, native, not invasive
USDA-ARS, 2007Corsica: Present
CABI, 2005UK: Present, native, not invasive
USDA-ARS, 2007Georgia (Republic of): Present, native, not invasive
USDA-ARS, 2007Greece: Present, native, not invasive
USDA-ARS, 2007Croatia: Present
CABI, 2005Hungary: Present, native, not invasive
USDA-ARS, 2007Ireland: Present, native, not invasive
USDA-ARS, 2007Iraq: Present, native, not invasive
USDA-ARS, 2007Iran: Present, native, not invasive
USDA-ARS, 2007Italy: Present, native, not invasive
USDA-ARS, 2007Lebanon: Present, native, not invasive
USDA-ARS, 2007Liechtenstein: Present
CABI, 2005Lithuania: Present
CABI, 2005Luxembourg: Present
CABI, 2005Latvia: Present
CABI, 2005Morocco: Present, native, not invasive
USDA-ARS, 2007Monaco: Present
CABI, 2005Moldova: Present
CABI, 2005Macedonia: Present
CABI, 2005Netherlands: Present, native, not invasive
USDA-ARS, 2007Norway: Present, native, not invasive
USDA-ARS, 2007Poland: Present, native, not invasive
USDA-ARS, 2007Portugal: Present, native, not invasive
USDA-ARS, 2007Romania: Present, native, not invasive
USDA-ARS, 2007Serbia: Present
CABI, 2005Russian Federation: Present, native, not invasive
USDA-ARS, 2007Central Russia: Present, native, not invasive
Royal Botanic Garden Edinburgh, 2007Southern Russia: Present, native, not invasive
USDA-ARS, 2007Sweden: Present, native, not invasive
USDA-ARS, 2007Slovenia: Present
CABI, 2005Slovakia: Present
CABI, 2005San Marino: Present
CABI, 2005Syria: Present, native, not invasive
USDA-ARS, 2007Tunisia: Present, native, not invasive
USDA-ARS, 2007Turkey: Present, native, not invasive
USDA-ARS, 2007Ukraine: Present, native, not invasive
USDA-ARS, 2007Yugoslavia (former): Present, native, not invasive
USDA-ARS, 2007
Distribution map (africa) Cyprus: Present, native, not invasive
USDA-ARS, 2007Algeria: Present, native, not invasive
USDA-ARS, 2007Egypt: Present, native, not invasive
USDA-ARS, 2007Spain: Present, native, not invasive
USDA-ARS, 2007Greece: Present, native, not invasive
USDA-ARS, 2007Israel: Present, native, not invasive
USDA-ARS, 2007Iraq: Present, native, not invasive
USDA-ARS, 2007Iran: Present, native, not invasive
USDA-ARS, 2007Lebanon: Present, native, not invasive
USDA-ARS, 2007Morocco: Present, native, not invasive
USDA-ARS, 2007Syria: Present, native, not invasive
USDA-ARS, 2007Tunisia: Present, native, not invasive
USDA-ARS, 2007Turkey: Present, native, not invasive
USDA-ARS, 2007South Africa: Present, introduced, invasive
Reichard et al., 2001
Distribution map (north america) Canada: Present
CABI, 2005British Columbia: Present, introduced, invasive
USDA-NRCS, 2007New Brunswick: Present, introduced
USDA-NRCS, 2007Nova Scotia: Present, introduced
USDA-NRCS, 2007Ontario: Present, introduced
USDA-NRCS, 2007Prince Edward Island: Present, introduced
USDA-NRCS, 2007Quebec: Present, introduced
USDA-NRCS, 2007USA: Present, introduced
CABI, 2005Alaska: Present, introduced
USDA-NRCS, 2007California: Present, introduced, invasive
USDA-NRCS, 2007Connecticut: Present, introduced
USDA-NRCS, 2007Delaware: Present, introduced
USDA-NRCS, 2007Illinois: Present, introduced
USDA-NRCS, 2007Kentucky: Present, introduced
USDA-NRCS, 2007Massachusetts: Present, introduced
USDA-NRCS, 2007Maryland: Present, introduced
USDA-NRCS, 2007Maine: Present, introduced
USDA-NRCS, 2007Michigan: Present, introduced
USDA-NRCS, 2007Montana: Present, introduced
USDA-NRCS, 2007New Hampshire: Present, introduced
USDA-NRCS, 2007New Jersey: Present, introduced
USDA-NRCS, 2007New York: Present, introduced, invasive
Hunter & Mattice, 2002; USDA-NRCS, 2007Ohio: Present, introduced
USDA-NRCS, 2007Oregon: Present, introduced, invasive
USDA-NRCS, 2007Pennsylvania: Present, introduced
USDA-NRCS, 2007Rhode Island: Present, introduced
USDA-NRCS, 2007Utah: Present, introduced
USDA-NRCS, 2007Vermont: Present, introduced
USDA-NRCS, 2007Washington: Present, introduced, invasive
USDA-NRCS, 2007Wisconsin: Present, introduced
USDA-NRCS, 2007West Virginia: Present, introduced
USDA-NRCS, 2007
Distribution map (central america) USA: Present, introduced
CABI, 2005
Distribution map (south america)
Distribution map (pacific) Australia: Present, introduced, invasive
Royal Botanic Gardens Sydney, 2007New South Wales: Present, introduced, invasive
Bass et al., 2006Queensland: Present, introduced
Royal Botanic Gardens Sydney, 2007South Australia: Present, introduced
Royal Botanic Gardens Sydney, 2007Tasmania: Present, introduced
Royal Botanic Gardens Sydney, 2007Victoria: Present, introduced
Royal Botanic Gardens Sydney, 2007New Zealand: Present, introduced, invasive
Owen, 1996