Cookies on Invasive Species Compendium

Like most websites we use cookies. This is to ensure that we give you the best experience possible.

Continuing to use www.cabi.org means you agree to our use of cookies. If you would like to, you can learn more about the cookies we use.

Datasheet

Centaurea solstitialis (yellow starthistle)

Summary

  • Last modified
  • 11 October 2017
  • Datasheet Type(s)
  • Pest
  • Invasive Species
  • Host Plant
  • Preferred Scientific Name
  • Centaurea solstitialis
  • Preferred Common Name
  • yellow starthistle
  • Taxonomic Tree
  • Domain: Eukaryota
  •   Kingdom: Plantae
  •     Phylum: Spermatophyta
  •       Subphylum: Angiospermae
  •         Class: Dicotyledonae
  • Summary of Invasiveness
  • Yellow starthistle is an invasive, exotic, seedy herbaceous annual. It invades disturbed areas such as roadsides, abandoned fields and waste places. It will occasionally invade crops, but is a serious rangeland weed,...

Don't need the entire report?

Generate a print friendly version containing only the sections you need.

Generate report

Pictures

Top of page
PictureTitleCaptionCopyright
Close-up of Yellow Star-thistle (Centaurea solstitialis).
TitleFlower head
CaptionClose-up of Yellow Star-thistle (Centaurea solstitialis).
CopyrightPublic Domain: originally from Agricultural Research Service, USDA.
Close-up of Yellow Star-thistle (Centaurea solstitialis).
Flower headClose-up of Yellow Star-thistle (Centaurea solstitialis).Public Domain: originally from Agricultural Research Service, USDA.
Centaurea solstitialis; severe infestation. North-central Idaho, USA.
TitleInfestation
CaptionCentaurea solstitialis; severe infestation. North-central Idaho, USA.
Copyright©Steve Dewey/Utah State University/Bugwood.org - CC BY 3.0 US
Centaurea solstitialis; severe infestation. North-central Idaho, USA.
InfestationCentaurea solstitialis; severe infestation. North-central Idaho, USA.©Steve Dewey/Utah State University/Bugwood.org - CC BY 3.0 US
Centaurea solstitialis infestation. North-central Idaho, USA.
TitleInfestation
CaptionCentaurea solstitialis infestation. North-central Idaho, USA.
Copyright©Steve Dewey/Utah State University/Bugwood.org - CC BY 3.0 US
Centaurea solstitialis infestation. North-central Idaho, USA.
InfestationCentaurea solstitialis infestation. North-central Idaho, USA.©Steve Dewey/Utah State University/Bugwood.org - CC BY 3.0 US
Centaurea solstitialis, near Davis, California.
TitleHabit
CaptionCentaurea solstitialis, near Davis, California.
Copyright©Chris Parker/Bristol, UK
Centaurea solstitialis, near Davis, California.
HabitCentaurea solstitialis, near Davis, California.©Chris Parker/Bristol, UK
Centaurea solstitialis infestation, showing dense habit. North-central Idaho, USA.
TitleHabit
CaptionCentaurea solstitialis infestation, showing dense habit. North-central Idaho, USA.
Copyright©Steve Dewey/Utah State University/Bugwood.org - CC BY 3.0 US
Centaurea solstitialis infestation, showing dense habit. North-central Idaho, USA.
HabitCentaurea solstitialis infestation, showing dense habit. North-central Idaho, USA.©Steve Dewey/Utah State University/Bugwood.org - CC BY 3.0 US
Centaurea solstitialis; an uprooted plant showing shape size and form. North-central Idaho, USA.
TitleWhole plant
CaptionCentaurea solstitialis; an uprooted plant showing shape size and form. North-central Idaho, USA.
Copyright©Steve Dewey/Utah State University/Bugwood.org - CC BY 3.0 US
Centaurea solstitialis; an uprooted plant showing shape size and form. North-central Idaho, USA.
Whole plantCentaurea solstitialis; an uprooted plant showing shape size and form. North-central Idaho, USA.©Steve Dewey/Utah State University/Bugwood.org - CC BY 3.0 US
Centaurea solstitialis; immature plant rosette. North-central Idaho, USA.
TitlePlant
CaptionCentaurea solstitialis; immature plant rosette. North-central Idaho, USA.
Copyright©Steve Dewey/Utah State University/Bugwood.org - CC BY 3.0 US
Centaurea solstitialis; immature plant rosette. North-central Idaho, USA.
PlantCentaurea solstitialis; immature plant rosette. North-central Idaho, USA.©Steve Dewey/Utah State University/Bugwood.org - CC BY 3.0 US
Centaurea solstitialis flowers; note large, sharp spikes. North-central Idaho, USA.
TitleFlower
CaptionCentaurea solstitialis flowers; note large, sharp spikes. North-central Idaho, USA.
Copyright©Steve Dewey/Utah State University/Bugwood.org - CC BY 3.0 US
Centaurea solstitialis flowers; note large, sharp spikes. North-central Idaho, USA.
FlowerCentaurea solstitialis flowers; note large, sharp spikes. North-central Idaho, USA.©Steve Dewey/Utah State University/Bugwood.org - CC BY 3.0 US
Centaurea solstitialis; dissected flower showing constituent parts. Note large, sharp spikes. North-central Idaho, USA.
TitleFlower
CaptionCentaurea solstitialis; dissected flower showing constituent parts. Note large, sharp spikes. North-central Idaho, USA.
Copyright©Steve Dewey/Utah State University/Bugwood.org - CC BY 3.0 US
Centaurea solstitialis; dissected flower showing constituent parts. Note large, sharp spikes. North-central Idaho, USA.
FlowerCentaurea solstitialis; dissected flower showing constituent parts. Note large, sharp spikes. North-central Idaho, USA.©Steve Dewey/Utah State University/Bugwood.org - CC BY 3.0 US

Identity

Top of page

Preferred Scientific Name

  • Centaurea solstitialis Linnaeus

Preferred Common Name

  • yellow starthistle

Other Scientific Names

  • Calcitrapa solstitialis Lamarck
  • Cyanus solstitialis Baumg.
  • Leucantha solstitialis A. Löve & D. Löve

International Common Names

  • English: Barnaby's thistle; golden starthistle; St. Barnaby's thistle; yellow centaury; yellow cockspur
  • Spanish: abremanos; abrepuno amarillo
  • French: centaurée du solstice

Local Common Names

  • Germany: Sonnenwend Flockenblume
  • Italy: spino giallo
  • Netherlands: zomercentaurie
  • South Africa: geeldissel; yellow centaurea

EPPO code

  • CENSO (Centaurea solstitialis)

Summary of Invasiveness

Top of page

Yellow starthistle is an invasive, exotic, seedy herbaceous annual. It invades disturbed areas such as roadsides, abandoned fields and waste places. It will occasionally invade crops, but is a serious rangeland weed, reducing forage quality and biodiversity. Greatest infestations are in areas of Mediterranean climate: cool, wet winters followed by hot, dry summers. It is listed as a noxious weed in 11 US states and two Canadian Provinces (Rice, 2003).

Taxonomic Tree

Top of page
  • Domain: Eukaryota
  •     Kingdom: Plantae
  •         Phylum: Spermatophyta
  •             Subphylum: Angiospermae
  •                 Class: Dicotyledonae
  •                     Order: Asterales
  •                         Family: Asteraceae
  •                             Genus: Centaurea
  •                                 Species: Centaurea solstitialis

Notes on Taxonomy and Nomenclature

Top of page

The currently accepted scientific name for yellow starthistle is Centaurea solstitialis. This designation was published by Linnaeus in 1753 (USDA-ARS, 2003). According to Ochsmann (2003), other names that have been proposed are Calcitrapa solstitialis (L.) Lam. (1778), Cyanus solstitialis (L.) Baumg. (1816) and Leucantha solstitialis (L.) Á. Löve & D. Löve (1961).

Description

Top of page Yellow starthistle is a pubescent winter annual, reproducing from seeds that germinate in the autumn or spring, forming a basal rosette. Basal leaves are 5-15 cm long, usually petioled and deeply lobed. Rosettes produce 7 to 26 leaves, and form a taproot that grows to depths of 1 m or more. Basal leaves tend to grow close to the ground in open places, but grow more upright at high densities, or in the presence of competing vegetation (Thomsen et al., 1994).

Rosettes bolt to form stems that are rigid, branched from near the base, bushy, woolly, greyish, and 150-750 mm tall. Stem leaves are alternate with cottony hairs, entire, stalked, narrow, sharp-pointed and lobeless. Upper leaves are narrow and short, 1.3-2.5 cm long (USDA, 1970).

Flower heads are terminal, urn-shaped with many inconspicuous bright-yellow, tubular flowers stiffly spreading above the narrow tip, the whole 1.8-2.5 cm high, without leafy bracts. Involucral bracts are numerous, closely overlapping, stiff and papery. Each of the middle bracts end in a stout, rigid, unbranched yellow spine, 1.2-2.5 cm long, with one or two pairs of very short spines at its base (USDA, 1970).

Flowers produce two kinds of glabrous achenes. One is smooth, dark brown, 2-3 mm long, oblong, and notched on one side, just above the base. Another is similar, but lighter coloured and has a pappus (plumed) of many white, thin, bristle-like spines of unequal length, 3-5 mm long. The plume helps the seed to disperse in the wind. More than 75% of the seeds are of the plumed type (USDA, 1970; Zouhar, 2002).

Plant Type

Top of page Annual
Biennial
Herbaceous
Seed propagated

Distribution

Top of page

Yellow starthistle has spread throughout temperate parts of the world from its native range in Eurasia and the Mediterranean. It is native to Armenia, Azerbaijan, Georgia, Iran, Iraq, Lebanon, Syria, Tajikistan, Turkey, Turkmenistan, Ukraine, Algeria, Tunisia, Albania, Bulgaria, France, Greece, Italy, Spain and former Yugoslavia (USDA-ARS, 2003). It is now found throughout Europe, in South America and Africa and as far as the Asian steppes, but does not persist in cold northerly areas (Maddox et al., 1985; Roche et al., 1986).

Yellow starthistle is present in 41 of 50 US states and four Canadian provinces. In the eastern two-thirds of the USA, infestations are sporadic and localized, and populations fail to establish (Zouhar, 2002; USDA-NRCS, 2002). It is a particular problem in California, where over 6.9 million hectares are infested, and is increasing in Idaho, Oregon and Washington (Maddox et al., 1985; Maddox and Mayfield, 1985; Callihan et al., 1989; Duncan, 2001). A record for Vermont in previous versions of this datasheets could not be traced and has been deleted (12/09/12).

Distribution Table

Top of page

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.

Continent/Country/RegionDistributionLast ReportedOriginFirst ReportedInvasiveReferenceNotes

Asia

ArmeniaPresentNative Invasive USDA-ARS, 2003
AzerbaijanPresentNative Invasive USDA-ARS, 2003
Georgia (Republic of)PresentNative Invasive USDA-ARS, 2003
IranPresentNative Invasive USDA-ARS, 2003
IraqPresentNative Invasive USDA-ARS, 2003
IsraelPresentIntroduced Invasive Turner et al., 1995
JordanPresentIntroduced Invasive Holm et al., 1979
LebanonPresentNative Invasive USDA-ARS, 2003
SyriaPresentNative Invasive USDA-ARS, 2003
TajikistanPresentNative Invasive USDA-ARS, 2003
TurkeyWidespreadNative Invasive Rosenthal et al., 1994; USDA-ARS, 2003
TurkmenistanPresentNative Invasive USDA-ARS, 2003

Africa

AlgeriaPresentNative Invasive USDA-ARS, 2003
BotswanaPresentIntroduced Invasive Maddox et al., 1985
EgyptPresentIntroduced Invasive Holm et al., 1979
South AfricaPresentIntroduced Invasive Maddox et al., 1985
SwazilandPresentIntroduced Invasive Holm et al., 1979
TunisiaPresentNative Invasive USDA-ARS, 2003

North America

Canada
-AlbertaPresentIntroduced Invasive Duncan, 2001
-British ColumbiaPresentIntroduced Invasive Duncan, 2001
-ManitobaPresentIntroduced Invasive Maddox et al., 1985; DiTomaso, 2001
-OntarioPresentIntroduced Invasive Maddox et al., 1985; DiTomaso, 2001
USAPresentIntroduced Invasive USDA-NRCS, 2002
-ArizonaPresentIntroduced Invasive Maddox et al., 1985; USDA-NRCS, 2002
-CaliforniaWidespreadIntroduced Invasive DiTomaso, 2001; Duncan, 2001
-ColoradoPresentIntroduced Invasive Maddox et al., 1985; USDA-NRCS, 2002
-ConnecticutPresentIntroduced Invasive USDA-NRCS, 2012
-DelawarePresentIntroduced Invasive USDA-NRCS, 2002
-FloridaPresentIntroduced Invasive USDA-NRCS, 2002
-IdahoWidespreadIntroduced Invasive Duncan, 2001; USDA-NRCS, 2002
-IllinoisPresentIntroduced Invasive Maddox et al., 1985; USDA-NRCS, 2002
-IndianaPresentIntroduced Invasive USDA-NRCS, 2002
-IowaPresentIntroduced Invasive Maddox et al., 1985; USDA-NRCS, 2002
-KansasPresentIntroduced Invasive Maddox et al., 1985; Duncan, 2001
-KentuckyPresentIntroduced Invasive Maddox et al., 1985; USDA-NRCS, 2002
-MarylandPresent, few occurrencesIntroduced Invasive Maddox et al., 1985; USDA-NRCS, 2002
-MassachusettsPresentIntroduced Invasive Maddox et al., 1985; USDA-NRCS, 2002
-MichiganPresentIntroduced Invasive USDA-NRCS, 2002
-MinnesotaPresentIntroduced Invasive Maddox et al., 1985; USDA-NRCS, 2002
-MissouriPresentIntroduced Invasive USDA-NRCS, 2002
-MontanaPresentIntroduced Invasive USDA-NRCS, 2002
-NebraskaPresentIntroduced Invasive Maddox et al., 1985; USDA-NRCS, 2002
-NevadaPresentIntroduced Invasive Duncan, 2001
-New HampshirePresentIntroduced Invasive Maddox et al., 1985; USDA-NRCS, 2002
-New JerseyPresentIntroduced Invasive USDA-NRCS, 2002
-New MexicoPresentIntroduced Invasive Duncan, 2001; USDA-NRCS, 2002
-New YorkPresentIntroduced Invasive Maddox et al., 1985; USDA-NRCS, 2002
-North CarolinaPresentIntroduced Invasive Maddox et al., 1985; USDA-NRCS, 2002
-North DakotaPresentIntroduced Invasive USDA-NRCS, 2002
-OhioPresentIntroduced Invasive Maddox et al., 1985; USDA-NRCS, 2002
-OklahomaPresentIntroduced Invasive USDA-NRCS, 2002
-OregonWidespreadIntroduced Invasive Duncan, 2001
-PennsylvaniaPresentIntroduced Invasive Maddox et al., 1985; USDA-NRCS, 2002
-Rhode IslandPresentIntroduced Invasive USDA-NRCS, 2002
-South CarolinaPresentIntroduced Invasive USDA-NRCS, 2002
-South DakotaPresentIntroduced Invasive Maddox et al., 1985; USDA-NRCS, 2002
-TennesseePresentIntroduced Invasive Maddox et al., 1985; USDA-NRCS, 2002
-TexasPresentIntroduced Invasive Maddox et al., 1985; USDA-NRCS, 2002
-UtahPresentIntroduced Invasive Maddox et al., 1985; USDA-NRCS, 2002
-VirginiaPresentIntroduced Invasive USDA-NRCS, 2002
-WashingtonWidespreadIntroduced Invasive Duncan, 2001
-West VirginiaPresentIntroduced Invasive USDA-NRCS, 2002
-WisconsinPresentIntroduced Invasive USDA-NRCS, 2002
-WyomingPresentIntroduced Invasive Maddox et al., 1985; USDA-NRCS, 2002

Central America and Caribbean

Trinidad and TobagoPresentIntroduced Invasive Holm et al., 1979

South America

ArgentinaPresentIntroduced Invasive Maddox et al., 1985
ChilePresentIntroduced Invasive Maddox et al., 1985
UruguayPresentIntroduced Invasive Holm et al., 1979; Maddox et al., 1985

Europe

AlbaniaPresentNative Invasive USDA-ARS, 2003
AustriaPresentIntroduced Invasive Tutin et al., 1976
BulgariaWidespreadNative Invasive USDA-ARS, 2003
Czech RepublicPresentIntroduced Invasive Tutin et al., 1976
Czechoslovakia (former)PresentIntroduced Invasive Tutin et al., 1976
FrancePresentNative Invasive USDA-ARS, 2003
-CorsicaPresentNative Invasive USDA-ARS, 2003
GermanyPresentIntroduced Not invasive Tutin et al., 1976
GreeceWidespreadNative Invasive USDA-ARS, 2003
HungaryPresentIntroduced Invasive Tutin et al., 1976
ItalyPresentNative Invasive USDA-ARS, 2003
MoldovaPresentIntroduced Invasive Turner et al., 1995
PolandPresentIntroduced Invasive Tutin et al., 1976
RomaniaPresentIntroduced Invasive Tutin et al., 1976
Russian FederationPresentIntroduced Invasive Tutin et al., 1976
-Southern RussiaPresentIntroduced Invasive Tutin et al., 1976
SerbiaPresentNative Invasive USDA-ARS, 2003
SpainWidespreadNative Invasive USDA-ARS, 2003
-Balearic IslandsPresentNative Invasive USDA-ARS, 2003
SwitzerlandPresentIntroduced Invasive Tutin et al., 1976
UKPresentIntroduced Invasive Tutin et al., 1976
UkrainePresentNative Invasive USDA-ARS, 2003
Yugoslavia (former)PresentNative Invasive USDA-ARS, 2003

Oceania

AustraliaPresentIntroduced Invasive Maddox et al., 1985
-New South WalesPresentIntroduced Invasive Maddox et al., 1985
-QueenslandPresentIntroduced Invasive Maddox et al., 1985
-VictoriaPresentIntroduced Invasive Maddox et al., 1985
New ZealandPresentIntroduced Invasive Maddox et al., 1985
Papua New GuineaPresentIntroduced Invasive Maddox et al., 1985

History of Introduction and Spread

Top of page There have been multiple introductions of yellow starthistle into California, USA, some from Europe, some from Chile, usually in contaminated lucerne seed. The earliest specimens in the USA were found in California, at Oakland in 1869 and Vacaville in 1887. It is now a widely distributed weed in the western USA (DiTomaso, 1998, 2001).

Risk of Introduction

Top of page

A major risk for introduction of C. solstitialis is through contaminated seeds (Zouhar, 2002).

Habitat

Top of page

Yellow starthistle thrives in areas with cool, wet winters followed by hot, dry summers. It is found in well-drained soils, especially where fire, over-grazing, road construction or other causes have seriously disturbed the vegetation (Maddox, 1981; Roche et al., 1986; Thomsen et al., 1996b, Hierro et al., 2011).

It is often found as an invader of grasslands, where it forms dense stands and crowds out annual grasses. In California, USA, most of the infestation is in the Central Valley and adjacent foothills. It is less commonly found in desert, high mountain and moist coastal sites (Zouhar, 2002).

Habitat List

Top of page
CategoryHabitatPresenceStatus
Terrestrial-managed
Cultivated / agricultural land Present, no further details Harmful (pest or invasive)
Disturbed areas Present, no further details Harmful (pest or invasive)
Managed forests, plantations and orchards Present, no further details Harmful (pest or invasive)
Managed grasslands (grazing systems) Present, no further details Harmful (pest or invasive)
Rail / roadsides Present, no further details Harmful (pest or invasive)

Hosts/Species Affected

Top of page Yellow starthistle is not a major crop pest, as it is easily destroyed by cultivation. It has occurred as a contaminant in lucerne or other grain crops, and contaminated seeds may have led to international distribution (Zouhar, 2002).

Host Plants and Other Plants Affected

Top of page
Plant nameFamilyContext
Medicago sativa (lucerne)FabaceaeMain

Biology and Ecology

Top of page

Yellow starthistle is an invasive herbaceous annual or biennial of the Asteraceae family that spreads by seeds, forming dense stands in open, sunny areas (Maddox, 1981).

Genetics

Yellow starthistle is diploid (2n=16), with a large amount of genetic variation (Sun, 1997; Sun and Ritland, 1998). Seeds from 34 distinct stands in California, Idaho and Oregon, USA, had wide biotypic variation for rosette area, plant height, number of branches, average number of flowers and seed production rate (Zouhar, 2002). Although hybrids with other Centaurea species have been found in Europe (Maddox et al., 1985), none have been found in California (Maddox, 1981).

Physiology and Phenology

Germination rate of plumed seed is higher in late autumn and winter, and that of plumeless seed is higher in spring. Over 90% of yellow starthistle seeds are able to germinate within a week after dispersal. Seeds germinate at both low and high temperatures, but emergence rate is nearly 100% between 10 and 20°C. Emergence is highest after early-season rainfall (Joley et al., 1997; Benefield et al., 2001). Although seeds can germinate in the dark, germination is greatly reduced in dark environments and appears to be stimulated by white light (Nolan and Upadhyaya, 1988; Joley et al., 1997).

Yellow starthistle has a very long life cycle for an annual plant, and it sometimes behaves as a biennial. It generally germinates from autumn through spring, but may not complete the life cycle until the following autumn or winter. The deep taproot extends below the zone of root competition of associated annual species and allows growth and flowering to occur well into the summer, long after other annual species have died (Prather, 1995).

Flowering and seed production times vary according to climate. Generally, plants bolt in the spring and flower in the summer. In California, yellow starthistle bolts from May to June. In June and July the flower buds form and spines appear at the tips of the bracts around the flower bud. Flowering takes place from June through August when the bright-yellow flowers open. In August, seeds are formed and leaves and stems begin to turn a straw colour. Seeds mature after the flowerhead fades from a bright yellow to a dull straw colour (Thomsen et al., 1994).

The small tubular florets produce two types of seed: light coloured, plumed seeds and darker, plumeless seeds. Florets in the centre of the head produce seeds with a ring of fine, white, thin bristles (plume). The outer circle of florets produce plumeless seeds. In general, the plants mature by late summer. By September or October, the plants dry out, lose leaves, and turn to silvery-grey skeletons with white, cottony terminal heads. In some places and under certain conditions, yellow starthistle survives over the winter, regrows in the spring, and dries out by early summer (Maddox, 1981).

When compared with the closely related congeners Centaurea calcitrapa and C. sulphurea which have a similar life history and have also been introduced to North America from Europe but have not become invasive there, C. solstitialis was found to grow faster, compete better and show faster evolution to larger seed size and seedling growth (Graebner et al., 2012).

Reproductive Biology

Yellow starthistle is monoecious, generally self-incompatible and pollinator-dependent. Fertilization is mostly by outcrossing, but self-fertilization sometimes occurs. Bumblebees and European honeybees are the most important pollinators (Harrod and Taylor, 1995; Zouhar, 2002).

Reproduction is entirely through the production of numerous seeds. Seed output ranges from 700 to 10,000 seeds per plant, with averages of between 38 and 45 per seedhead (Maddox, 1981). Seed rain can be as dense as 29,000/m² (Callihan et al., 1993). Most seeds germinate within a year, but some can last 10 years or more in the soil (Callihan et al., 1993; Lanini et al., 1995; Thomsen et al., 1996b).

The plumed, lighter-coloured seeds disperse quickly after maturity, and the darker, plumeless seeds persist in the flowerhead until windy weather or other disturbances break them up (Roche, 1965). By December, the bracts are usually lost from the flower, and the white, cottony base of the head is revealed. Although most yellow starthistle seeds fall within 0.6 m of the parent plant (Roche, 1992), the plumed seeds can disperse 1.5 m by wind, and many seeds disperse over longer distances in fur, feathers or as a result of human activity. In California, human activity probably accounts for most of the seed dispersal (Callihan et al., 1989; Roche, 1992; Thomsen et al., 1996b).

Environmental Requirements

Yellow starthistle is best adapted to open grasslands with an average annual precipitation of between 250 and 1500 mm, and most large infestations are found below 1500 m. It is generally associated with well-drained, deep silt loam and loam soils, but can tolerate shallow, rocky areas (Zouhar, 2002). The optimum environment is cool, wet winters followed by hot, dry summers. It can survive mean annual temperatures of between 4.3 and 18°C (Maddox et al. 1985; Climate, 2003). Limiting factors may be moisture during summer drought and light during winter growth (Zouhar, 2002). Hardiness, wide climate profile and abundant seed production of yellow starthistle make it potentially invasive everywhere it is introduced. However, it is uncommon in deserts and moist coastal sites (Zouhar, 2002).

At its northern limits, it appears on south-facing slopes where there is more heat and light. Yellow starthistle seedlings can survive extended frost periods, but mature plants rarely survive the winter in cold climates. Cold tolerance appears to be lost during the transition from vegetative to reproductive phases (DiTomaso, 2001).

A study by Dukes et al. (2011) suggests that the prevalanece of yellow starthistle may increase in western North America with warmer climatic conditions and  elevated CO2 and nitrate deposition levels.

Associations

Yellow starthistle is found in grasslands. In the Pacific Northwest, it is found with cheatgrass (Bromus tectorum). In Washington, it is found with bluebunch wheatgrass (Pseudoroegneria spicata) and Idaho fescue (Festuca idahoensis) (DiTomaso, 2001).

Latitude/Altitude Ranges

Top of page 1500

Air Temperature

Top of page
Parameter Lower limit Upper limit
Absolute minimum temperature (ºC) -21
Mean annual temperature (ºC) 4 18
Mean maximum temperature of hottest month (ºC) 28 34
Mean minimum temperature of coldest month (ºC) -21 5

Rainfall

Top of page
ParameterLower limitUpper limitDescription
Dry season duration6number of consecutive months with <40 mm rainfall
Mean annual rainfall2501500mm; lower/upper limits

Rainfall Regime

Top of page Winter

Soil Tolerances

Top of page

Soil drainage

  • free
  • free

Soil reaction

  • neutral

Soil texture

  • medium

Natural enemies

Top of page
Natural enemyTypeLife stagesSpecificityReferencesBiological control inBiological control on
Aceria solstitialis Herbivore Leaves
Bangasternus fausti Herbivore
Bangasternus orientalis Herbivore Seeds North America; Oregon
Chaetorellia australis Herbivore Seeds USA; Oregon
Eustenopus villosus Herbivore Seeds USA; Oregon
Larinus curtus Herbivore Seeds
Puccinia jaceae Pathogen
Urophora jaculata Herbivore Seeds
Urophora quadrifasciata Herbivore
Urophora sirunaseva Herbivore Seeds USA; Oregon

Notes on Natural Enemies

Top of page

For information on natural enemies of C. solstitialis, see Balciunas and Villegas (1999) and Rosenthal et al. (1994).

Means of Movement and Dispersal

Top of page

Natural Dispersal (non-biotic)

As the seedheads deteriorate, plumeless seeds drop to the soil near the parent plant (Callihan et al., 1989). Plumed seeds usually land no more than a metre away, and maximum wind dispersal is about 5 m (Roche, 1992).

Vector Transmission (biotic)

Plumed seeds stick to fur and clothing, resulting in dispersal through short to medium distances by humans and animals. Birds such as pheasants, quail, house finches and goldfinches feed heavily on yellow starthistle seeds and also are capable of long-distance dispersal (Roche, 1992).

Agricultural Practices

Long-distance dispersal of yellow starthistle seed is often directly related to human activities and occurs by movement of livestock, vehicles, equipment and contaminated hay and crop seed (DiTomaso, 2001).

There have been multiple introductions of yellow starthistle to the USA, mainly through contaminated lucerne seed (Maddox et al., 1985; Luster et al., 2001). It is often spread as a contaminant in crop seed, but is also carried in hay or straw or by vehicles including construction or maintenance equipment (Maddox, 1981; Roche et al., 1986; Roche and Talbott, 1986; DiTomaso, 1998).

Accidental Introduction

In California, extensive road building, suburban development and expansion in the ranching industry since the 1960s, have contributed to the rapid and long-range dispersal of seed and the establishment of new satellite populations (DiTomaso, 2001).

Intentional Introduction

As it is not an ornamental, C. solstitialis has probably never been intentionally introduced.

Pathway Causes

Top of page
CauseNotesLong DistanceLocalReferences
Crop production Yes
Digestion and excretion Yes
Hitchhiker Yes

Pathway Vectors

Top of page
VectorNotesLong DistanceLocalReferences
Clothing, footwear and possessions Yes
Land vehiclesConstruction Yes
Livestock Yes
Machinery and equipment Yes
Plants or parts of plants Yes Yes

Plant Trade

Top of page
Plant parts liable to carry the pest in trade/transportPest stagesBorne internallyBorne externallyVisibility of pest or symptoms
True seeds (inc. grain) seeds No Yes
Plant parts not known to carry the pest in trade/transport
Bark
Bulbs/Tubers/Corms/Rhizomes
Flowers/Inflorescences/Cones/Calyx
Fruits (inc. pods)
Growing medium accompanying plants
Leaves
Roots
Seedlings/Micropropagated plants
Stems (above ground)/Shoots/Trunks/Branches
Wood

Impact Summary

Top of page
CategoryImpact
Animal/plant collections None
Animal/plant products Negative
Biodiversity (generally) Negative
Crop production Negative
Environment (generally) Negative
Fisheries / aquaculture None
Forestry production None
Human health None
Livestock production Negative
Native fauna None
Native flora Negative
Rare/protected species Negative
Tourism None
Trade/international relations None
Transport/travel None

Economic Impact

Top of page

Yellow starthistle is toxic to horses in large amounts, causing equine nigropallidal encephalomalacia or 'chewing disease'. The first signs of poisoning are an inability to eat or drink as the muscles of the lips, face and tongue become stiff and swollen, giving the horse a fixed expression. Poisoning eventually results in permanent brain damage, and severely affected animals eventually die of thirst and starvation. Sheep, cows and other livestock are not affected (Kingsbury, 1964; Callihan et al., 1982; DiTomaso, 1998).

Millions of dollars in losses result from interference with livestock grazing and forage harvesting procedures, and lower yield and forage quality of rangelands (Callihan et al., 1982; Roché and Roché, 1988). Because of the spiny nature of yellow starthistle, livestock and wildlife avoid grazing in heavily infested areas. Livestock have slower weight gain, and reduced quality of meat, milk, wool and hides (DiTomaso, 2000).

Yellow starthistle is the most important roadside weed problem in much of central and northern California and has, on occasion, caused problems in dryland cereals, orchards, vineyards, cultivated crops and wastelands (Maddox et al., 1985).

It can also reduce land value and access to recreational areas (DiTomaso, 1998; Roche and Roche, 1988), reduce wildlife habitat and forage, displace native plants, and decrease native plant and animal diversity (Sheley and Larson, 1994). Dense infestations threaten natural ecosystems by fragmenting plant and animal habitats (Scott and Pratini, 1995).

Depletion of rangeland moisture has a significant impact on forage plants. Estimated losses due to water depletion are $16 to $56 million each year in California (DiTomaso, 2001).

Environmental Impact

Top of page

Existing vegetation is displaced wherever yellow starthistle invades. In dense stands, both large canopied, deep-rooted plants receiving full sunlight, and an understorey of smaller, shallow-rooted, shaded plants are present. Yellow starthistle can halt the germination and establishment of native plants by complete niche domination for example depleting soil moisture (Spencer et al., 2011). Native blue oak (Quercus douglasii) and purple needlegrass (Nassella pulchra) populations are threatened in North America (DiTomaso, 2001).

Social Impact

Top of page Human health is not directly affected by yellow starthistle.

Risk and Impact Factors

Top of page

Impact mechanisms

  • Competition - monopolizing resources
  • Produces spines, thorns or burrs

Impact outcomes

  • Negatively impacts agriculture
  • Negatively impacts animal health
  • Negatively impacts tourism
  • Reduced amenity values
  • Reduced native biodiversity

Invasiveness

  • Has high reproductive potential
  • Has propagules that can remain viable for more than one year
  • Highly adaptable to different environments
  • Highly mobile locally
  • Invasive in its native range
  • Proved invasive outside its native range

Likelihood of entry/control

  • Difficult/costly to control
  • Highly likely to be transported internationally accidentally

Uses

Top of page Yellow starthistle is a major souce of pollen and nectar for honeybees. Some stages of the plant can be grazed by animals (Zouhar, 2002).

Uses List

Top of page

Materials

  • Poisonous to mammals

Similarities to Other Species/Conditions

Top of page

There are two other Centaurea species in California with yellow flowers and long spines on the seedheads: Malta starthistle (Centaurea melitensis) and Sicilian starthistle (Centaurea sulphurea). The corolla of C. sulphurea is larger than 25 mm, whereas yellow starthistle is 10-20 mm. The central spikes of main floral bracts are smaller on C. melitensis, 5-10 mm, versus 10-25 mm on C. solstitialis. In other western states, bighead knapweed (Centaurea macrocephala) also has yellow flowers but does not have long, sharp spines on the flowerheads (DiTomaso, 2001).

Prevention and Control

Top of page

Introduction

Yellow starthistle responds best to integrated pest management (IPM) programmes that prevent seed formation and deplete the seed bank. Timing is critical. The grazing period should be timed to the palatable bolting stage in late May or June, before spines are formed (Thomsen et al., 1989, 1991). Stands should be mowed during early flowering when 2-5% of the plants show a bright yellow colour (Thomsen et al., 1997). Cultivation should be timed with autumn emergence, after the rains begin. Repeated cultivations are generally needed to control each new flush of seedlings. Cultivation will also bring deeply buried seeds to the surface where conditions are favourable for germination (Lanini et al., 1995; Thomsen et al., 1996b). Burning should be done at the end of the rainy season, but prior to the formation of viable seeds. According to Thomsen et al. (1996b), the best time to burn is probably when plants are in the early flowering stage, before seed formation.

Cultural Control

Revegetation is critical for preventing weed infestations where the soil has been disturbed or the vegetation removed. Because of the aggressive nature of yellow starthistle, dense stands of perennial grasses, oats, wheat and legumes such as clover are needed (Woo et al., 1999).

Desirable plant species should be chosen with the site in mind, and a preliminary small-scale planting may be necessary. According to Thomsen et al. (1996b), more than a year will be required to find the species or mix of species most effective, because species that are excellent in the first year may be disappointing in subsequent years.

By depleting soil moisture and providing additional shade, early-growing perennial grasses can help to suppress yellow starthistle. 'Berber' orchardgrass (Dactylis glomerata) and Idaho fescue (Festuca idahoensis), which begin growth early, suppress thistle and other annual weeds more effectively than later growing perennial grasses such as intermediate Agropyron intermedium [Elytrigia intermedia subsp. intermedia] and tall A. elongatum [Elytrigia elongata] wheatgrasses (Borman et al., 1991).

Perennial grasses are slow to establish and most require at least 2 years to be competitive. Thomsen et al. (1994) recommended using a no-till drill for reseeding, as this allows seeding without turning the soil, and helps to keep deeply buried starthistle seeds from germinating.

Thomsen et al. (1996a, b) reseeded with dryland legumes. Subterranean clovers (Trifolium spp.) were chosen as pasture plants because they are palatable, self-seeding, and produce flowers and seeds below the bite of grazing animals. In addition, strong winter- and spring-growth make them useful as cover crops in vineyards and orchards.

Well-timed, heavy grazing by goats, sheep and cattle can reduce yellow starthistle seed production and biomass. Grazing should be timed to the bolting stage in late May or June, before spines are on the plant. Grazing earlier, at the rosette stage, favours yellow starthistle development by elimination of competitive plants which do not regrow as quickly. As most defoliated yellow starthistle will recover from one grazing, it is necessary to bring the animals back one to four times at about 2 week intervals under rotational grazing. Alternately, grazers can be left on site for 2-3 months under a continuous grazing regimen (Thomsen et al., 1993).

Mechanical Control

Hand-pulling, hoeing or weed whipping can be effective for isolated plants or small populations. The best time to remove plants is after they have bolted and before they have produced seeds (DiTomaso, 2001).

Mowing can significantly reduce the density of yellow starthistle, but mowing heights must be set correctly and mowings must be accurately timed. Plants mowed at ground level do not survive; however, in practice this is impractical because rocks and debris can interfere with mower blades. Mowing at a height of 10 cm gives the most effective reduction of yellow starthistle seedhead number and biomass (Benefield et al., 1999).

Late mowing is more effective than early mowing, but mowing should not be attempted after seeds are produced. Viable seeds are produced after the bright yellow flowers turn to a dull straw colour. Mowing during early flowering when 2-5% of the plants show a bright yellow colour gives the greatest reductions in both flower and seedling density (Thomsen et al., 1997).

Mowing success also depends on soil conditions. It is most effective when soil moisture is low, and one mowing might be enough. In most situations, one or two more mowings will be necessary and should be done once flowering resumes, approximately 4-6 weeks after the initial mowing. Since yellow starthistle growth varies according to site conditions and climactic factors, monitoring is necessary to time mowing correctly (Thomsen et al., 1997).

Starthistle can either grow upright or can develop an extensive low-branching growth habit. Starthistle that grows with a low-branching form is very difficult to control with mowing. For this reason, the integration of mowing with competing vegetation is important. Competing vegetation early in the year forces the starthistle to grow upright, and mowing is then more effective later in the season (Benefield et al., 1999). Competing vegetation also cuts in half the number of flowerheads per starthistle plant (Pitcairn et al., 1998).

Mowing before early flowering, soon after the bolting stage, will actually increase yellow starthistle densities. In addition, mowing should not be done if desirable vegetation is extensively flowering or setting seed, as this will favour starthistle (Lanini et al., 1995; Thomsen et al., 1997).

Cultivation can effectively control yellow starthistle. The equipment used depends on soil condition and plant stage. For loose soil and small plants, spike-tooth or spring-harrows are usually sufficient. For larger plants, a rotary hoe or disk is best (Thomsen et al., 1996b).

The best time to begin cultivation is when emergence begins in the autumn. Repeated cultivations are generally needed to control each new flush of seedlings. Cultivation will also bring deeply buried seeds to the surface where conditions are favourable for germination. Repeat cultivation then depletes the seedbank (Lanini et al., 1995; Thomsen et al., 1996b).

Chemical Control

Herbicides alone are not a good way of dealing with starthistle in a rangeland situation. Most pre-emergent herbicides are not registered for rangeland, and repeated applications of post-emergent herbicides such as 2,4-D and others are needed to have any long-term effect. Use of clopyralid, which has both pre- and post-emergent activity, can lead to a build-up of other undesirable weed species such as medusahead (Taeniatherum caput-medusae) or barbed goatgrass (Aegilops triuncialis) (DiTomaso, 1996; DiTomaso et al., 1999). Repeated use of herbicides leads to yellow starthistle resistance (Fuerst et al., 1996).

If herbicides are used at all, they should be part of an IPM programme to establish competing vegetation (Woo et al., 1999). Generally, picloram and clopyralid are the most effective herbicides. They are best applied at the early rosette stage in the first or second year of a long-term IPM management plan. Spot applications of glyphosate at the bolting or early flowering stage can sometimes be helpful for isolated plants or small populations (DiTomaso, 2001).

Biological Control

Six insect natural enemies of yellow starthistle have been imported into the USA from Greece and are established as biological control agents (Rees et al.,1996). Three of these are weevils, including Bangasternus orientalis (brought into the USA in 1985), Eustenopus villosus (1990) and Larinus curtus (1992). The rest of the biocontrol agents are flies, including one gall fly Urophora sirunaseva (1985), the peacock fly Chaetorellia australis (1989) and the false peacock fly C. succinea (1989) (Maddox et al., 1991; Turner et al., 1994, 1995, 1996a, b; Balciunas and Villegas, 1999). The gall fly U. jaculata was imported, but did not establish (Turner et al., 1995; Pitcairn et al., 1998).

The false peacock fly (C. succinea) was introduced accidentally along with the peacock fly (C. australis). Ironically, the true peacock fly the USDA was trying to import did not establish well in California, but the false peacock fly is thriving at 415 survey sites in 44 counties. The false peacock fly is also more effective, infesting up to 50% of thistle heads in many sites, while the true peacock fly typically never infests more than 5% at a site (Balciunas and Villegas, 1999).

All six insects attack the seedhead and reduce seed production. They are all highly specific to yellow starthistle and do not attack commercially valuable or native plants. It is still too early to know their efficacy as control agents, but adult feeding damage by the hairy weevil E. villosus can be very extensive at release sites 3 years or older (Pitcairn et al., 1998). At one site, seedheads had 78% fewer seeds due to attack by false peacock fly (Balciunas and Villegas, 1999). In another area, a combination of E. villosus and C. succinea reduced seed production by 43-76% (DiTomaso, 2001).

There are few diseases of adult yellow starthistle in North America. However, seedling mortality due to disease can be extensive, particularly in high density settings. The most effective pathogen in North America may be Sclerotinia minor, but this microbe has too wide a host range to be useful as a biocontrol agent. So far, the rust fungus Puccinia jaceae var. solstitialis shows the greatest promise (Woods, 1998).

Integrated Control

Though potentially serious, C. solstitialis can be controlled by an integrated programme of monitoring, biological control, proper grazing rotations, mulching, mowing, controlled burning and reseeding with competitive vegetation. Such an integrated approach can effectively control the weed without the use of toxic herbicides (Woo et al., 1999).

Cultivation should always be integrated with revegetation. Dense sowing of oats or wheat in autumn, after thoroughly tilling, mulching and fertilizing may completely eliminate the weed. One approach is to use a wheat straw mulch, at least 13 mm deep, into which 56 kg/ha of oats have been mixed (Dremann, 1992, 1996).

Grazing should be combined with other control methods such as competitive plantings and mowing. Animals must be confined with the starthistle by temporary electric fencing, and moved at times to adjust grazing pressure. If goats are used, exclosures may be needed to protect patches of native or desirable vegetation within the grazed area (Popay and Field, 1996).

Mowing should be integrated with revegetation. Early mowing enhances subclover performance because it reduces shading by tall annual grasses. Some varieties can form a dense network of interwoven stems and leafy canopies that reduce sunlight to yellow starthistle rosettes. But, whatever the variety used, competition from subclover by itself is insufficient to control yellow starthistle, and late spring or early summer mowings are required (Thomsen et al., 1996a).

Burning should also be combined with revegetation to prevent re-invasion. Burning should be done at the end of the rainy season, but before the formation of viable seeds. The best time to burn is the early flowering stage, prior to seed formation. Sowing grass seed the winter before a planned burn can provide fuel for the burns. Total combustion is not necessary. Plants can be killed by foliar scorching and stem girdling. A flamethrower can be used to scorch patches of accessible plants that do not burn (Hastings and DiTomaso, 1996; Thomsen et al., 1996b).

One successful burning programme in California produced a 90% reduction in relative starthistle cover, increased perennial grass cover by 300% and reduced the soil seed bank by over 99% (Hastings and DiTomaso, 1996).

References

Top of page

Balciunas J; Villegas B, 1999. Two new seed head flies attack yellow starthistle. California Agriculture, 53(2):8-11; 8 ref.

Benefield CB; DiTomaso JM; Kyser GB; Orloff SB; Churches KR; Marcum DB; Nader GA, 1999. Success of mowing to control yellow starthistle depends on timing and plant's branching form. California Agriculture, 53(2):17-21; 6 ref.

Benefield CB; DiTomaso JM; Kyser GB; Tschohl A, 2001. Reproductive biology of yellow starthistle: maximizing late-season control. Weed Science, 49(1):83-90; 21 ref.

Borman MM; Krueger WC; Johnson DE, 1991. Effects of established perennial grasses on yields of associated annual weeds. Journal of Range Management, 44(4):318-322

Callihan RH; Northam FE; Johnson JB; Michalson EL; Prather TS, 1989. Yellow Starthistle Biology and Management in Pasture and Rangeland. Moscow, ID: University of Idaho Cooperative Extension Service, Agricultural Experiment Station.

Callihan RH; Prather TS; Northam FE, 1993. Longevity of yellow starthistle (Centaurea solstitialis) achenes in soil. Weed Technology, 7(1):33-35

Callihan RH; Sheley RL; Thill DC, 1982. Yellow Starthistle, Identification and Control. Moscow, ID: Current Information Series No. 634, University of Idaho Cooperative Extension Service.

Climate, 2003. Average temperatures and rainfalls of the world. www.worldclimate.com.

DiTomaso JM, 1996. Yellow starthistle: chemical control. Proceedings California Exotic Pest Plant Council, 2:81-85.

DiTomaso JM, 1998. Biology and impact of yellow starthistle. In: Hoddle MS, ed. Innovation in Biological Control Research. Proceedings of the California Conference on Biological Control, June 10-11, 1998. Berkeley, USA: University of California, 82-84.

DiTomaso JM, 2000. Invasive weeds in rangelands: species, impacts, and management. Weed Science, 48(2):255-265.

DiTomaso JM, 2001. Yellow starthistle information, Davis, CA: University of California, Weed Research and Information Center. Website: http://wric.ucdavis.edu/yst.

DiTomaso JM; Kyser GB; Orloff SB; Enloe SF; Nader GA, 1999. New growth regulator herbicide provides excellent control of yellow starthistle. California Agriculture, 53(2):12-16; 5 ref.

Dremann CC, 1992. Starthistle Control with Grasses. Redwood City, CA: Redwood City Seed, P.O. Box 361.

Dremann CC, 1996. Personal Communication. Nov. 18, 1996. Redwood City, CA: Redwood City Seed Company, 415/325-7333.

Dukes JS; Chiariello NR; Loarie SR; Field CB, 2011. Strong response of an invasive plant species (Centaurea solstitialis L.) to global environmental changes. Ecological Applications, 21(6):1887-1894. http://www.esajournals.org/doi/full/10.1890/11-0111.1

Duncan CL, 2001. Knapweed management: another decade of change. In: Smith L, ed. Proceedings of the 1st International Knapweed Symposium of the 21st Century,Coeur d'Alene, ID. March 15-16, 2001. Albany, CA: U.S. Department of Agriculture, Agricultural Research Service, 1-7.

Fuerst EP; Sterling TM; Norman MA; Prather TS; Irzyk GP; Wu Y; Lownds NK; Callihan RH, 1996. Physiological characterization of picloram resistance in yellow starthistle. Pesticide Biochemistry and Physiology, 56(2):149-161; 20 ref.

Graebner RC; Callaway RM; Montesinos D, 2012. Invasive species grows faster, competes better, and shows greater evolution toward increased seed size and growth than exotic non-invasive congeners. Plant Ecology, 213(4):545-553. http://springerlink.metapress.com/link.asp?id=100328

Harrod RJ; Taylor RJ, 1995. Reproduction and pollination biology of Centaurea and Acroptilon species, with emphasis on C. diffusa. Northwest Science, 69(2):97-105

Hastings M; DiTomaso JM, 1996. The use of fire for yellow starthistle (Centaurea solstitialis) management and the restoration of native grasslands at Sugarloaf Ridge State Park. California Exotic Pest Plant Council News, 4:4-6.

Hierro JL; Lortie CJ; Villarreal D; Estanga-Mollica ME; Callaway RM, 2011. Resistance to Centaurea solstitialis invasion from annual and perennial grasses in California and Argentina. Biological Invasions, 13(10):2249-2259. http://www.springerlink.com/content/q0048g178r15v699/

Holm LC; Pancho JV; Herberger JP; Plucknett DL, 1979. A Geographical Atlas of World Weeds. New York: Wiley-Interscience.

Joley DB; Maddox DM; Mackey BE; Schoenig SE; Casanave KA, 1997. Effect of light and temperature on germination of dimorphic achenes of Centaurea solstitialis in California. Canadian Journal of Botany, 75(12):2131-2139; 16 ref.

Julien MH; Griffiths MW, 1998. Biological control of weeds: a world catalogue of agents and their target weeds. Biological control of weeds: a world catalogue of agents and their target weeds., Ed. 4:x + 223 pp.

Kingsbury JM, 1964. Poisonous plants of the United States and Canada. Englewood Cliffs, New Jersey, USA: Prentice-Hall Inc.

Lanini WT; Thomsen C; Prather TS; Smith MJ; Turner CE; Elmore CL; Vayssieres M; Williams WA, 1995. Yellow Starthistle. Oakland, USA: Pest Notes No. 3, University of California Division of Agriculture and Natural Resources.

Luster DG; Bruckart WL; Pitcairn M; Cristafaro M, 2001. Comparison of North American and Eurasian yellow starthistle populations using AFLP fragment pattern analysis. In: Smith L, ed. Proceedings, 1st International Knapweed Symposium of the 21st century; March 15-16, 2001, Coeur d'Alene, ID. Albany, USA: U.S. Department of Agriculture, Agricultural Research Service.

Maddox DM, 1981. Introduction, phenology and density of yellow starthistle in coastal, intercoastal and central valley situations in California. USDA Agricultural Research Results, No. ARR-W-20:33 pp.

Maddox DM; Joley DB; Mayfield A; Mackey BE, 1991. Impact of Bangasternus orientalis (Coleoptera: Curculionidae) on achene production of Centaurea solstitialis (Asterales: Asteraceae) at a low and high elevation site in California. Environmental Entomology, 20(1):335-337

Maddox DM; Mayfield A, 1985. Yellow starthistle infestations are on the increase. California Agriculture, 39(11/12):10-12

Maddox DM; Mayfield A; Poritz NH, 1985. Distribution of yellow starthistle (Centaurea solstitialis) and Russian knapweed (Centaurea repens). Weed Science, 33(3):315-327

Nolan DG; Upadhyaya MK, 1988. Primary seed dormancy in diffuse and spotted knapweed. Canadian Journal of Plant Science, 68(3):775-783

Ochsmann J, 2003. Centaurea Homepage. http://www.ochsmann.info/centaurea/centaurea-America.htm.

Pitcairn MJ; Joley DB; Woods DM, 1998. Impact of introduced insects for biological control of yellow starthistle. In: Hoddle MS, ed. Innovation in Biological Control Research. Proceedings of the California Conference on Biological Control, June 10-11, 1998. Berkeley, USA: University of California, 88-92.

Popay I; Field R, 1996. Grazing animals as weed control agents. Weed Technology, 10(1):217-231; 4 pp. of ref.

Prather T, 1995. Biology and recognition of various thistle growth stages. In: Smith MJ, Ouwerkerk BW, comps. Thistle Management in California. Atascadero, CA, USA: San Luis Obispo County, Department of Agriculture.

Rees NE; Quimby PC Jr; Piper GL; Coombs EM; Turner CE; Spencer NR; Knutson LV, eds. , 1996. Biological Control of Weeds in the West. Bozeman, MT: Western Society of Weed Science, USDA/ARS, Montana Department of Agriculture, Montana State University.

Rice PM, 2003. INVADERS Database System. Division of Biological Sciences, University of Montana, Missoula, USA. http://invader.dbs.umt.edu.

Roche BF Jr, 1992. Achene dispersal in yellow starthistle (Centaurea solstitialis L.). Northwest Science, 66(2):62-65

Roche BF Jr; Piper GL; Talbot CJ, 1986. Knapweeds of Washington. Pullman, WA:Washington State University, Cooperative Extension, College of Agriculture and Home Economics.

Roché BF Jr; Talbott CJ, 1986. The collection history of Centaureas found in Washington State. Research Bulletin, Agriculture Research Center, Washington State University, No.XB 0978:36pp.

Roche BFJr, 1965. Ecologic Studies of Yellow Starthistle (Centaurea solstitialis). Moscow, ID: PhD Dissertation, Univeristy of Idaho.

Roche CT; Roche BF Jr, 1988. Distribution and amount of four knapweed (Centaurea L.) species in eastern Washington. Northwest Science, 62(5):242-253

Rosenthal SS; Davarci T; Ercis A; Platts B; Tait S, 1994. Turkish herbivores and pathogens associated with some knapweeds (Asteraceae: Centaurea and Acroptilon) that are weeds in the United States. Proceedings of the Entomological Society of Washington, 96(1):162-175

Scott T; Pratini N, 1995. Habitat fragmentation: the sum of the pieces is less than the whole. California Agriculture, 49(6):56.

Sheley RL; Larson LL, 1994. Observation: comparative life-history of cheat-grass and yellow starthistle. Journal of Range Management, 47(6):450-456

Spencer D; Enloe S; Liow PS; Ksander G; Carruthers R, 2011. Does superior competitive ability explain yellow Starthistle's (Centaurea solstitialis) successful invasion of annual grasslands in California? Invasive Plant Science and Management, 4(3):284-295. http://wssajournals.org/loi/ipsm

Stoeva A; Harizanova V; Lillo Ede; Cristofaro M; Smith L, 2012. Laboratory and field experimental evaluation of host plant specificity of Aceria solstitialis, a prospective biological control agent of yellow starthistle. Experimental and Applied Acarology, 56(1):43-55. http://www.springerlink.com/content/n73j658401287070/fulltext.html

Sun M, 1997. Population genetic structure of yellow starthistle (Centaurea solstitialis), a colonizing weed in the western United States. Canadian Journal of Botany, 75:1470-1478.

Sun M; Ritland K, 1998. Mating system of yellow starthistle (Centaurea solstitialis), a successful colonizer in North America. Heredity, 80:225-232.

Thomsen CD; Robbins ME; Larson S, 1991. Yellow Starthistle Control. Davis, CA: Range Science Report No. 30, Department of Agronomy and Range Science, University of California.

Thomsen CD; Vayssières MP; Williams WA, 1997. Mowing and subclover plantings suppress yellow starthistle. California Agriculture, 51(6):15-20; 4 ref.

Thomsen CD; Williams WA; George MR; McHenry WB; Bell FL; Knight RS, 1989. Managing yellow starthistle on rangeland. California Agriculture, 43(5):4-7

Thomsen CD; Williams WA; Olkowski W; Pratt DW, 1996. Grazing, mowing and clover plantings control yellow starthistle. IPM Practitioner, 18(2):1-4; 1 ref.

Thomsen CD; Williams WA; Vayssiéres MP, 1996. Yellow starthistle management with grazing, mowing, and competitive plantings. Proceedings California Exotic Pest Plant Council, 2:65-68.

Thomsen CD; Williams WA; Vayssiéres MP; Bell FL, 1994. Yellow Starthistle Control. Davis, USA: Range Science Report No. 33, Department of Agronomy and Range Science, Cooperative Extension, University of California.

Thomsen CD; Williams WA; Vayssiéres MP; Bell FL; George MR, 1993. Controlled grazing on annual grassland decreases yellow starthistle. California Agriculture, 47:36-40.

Thomsen CD; Williams WA; Vayssiéres MP; Turner CE; Lanini WT, 1996. Yellow Starthistle Biology and Control. Oakland, CA: Publication No. 21541, University of California, Division of Agriculture and Natural Resources.

Turner CE; Johnson JB; McCaffrey JP, 1995. Yellow starthistle, Centaurea solstitialis. In: Nechols JR, Andres LA, Beardsley JW, Goeden RD, Jackson CG, eds. Biological Control in the U.S. Western Region: Accomplishments and Benefits of Regional Research Project W-84, 1964-1989. Oakland, CA: Pub. No. 3361, Division of Agriculture and Natural Resources, University of California, 270-275.

Turner CE; Piper GL; Coombs EM, 1996. Chaetorellia australis (Diptera: Tephritidae) for biological control of yellow starthistle, Centaurea solstitialis (Compositae), in the western USA: establishment and seed destruction. Bulletin of Entomological Research, 86(2):177-182; 18 ref.

Turner CE; Piper GL; Coombs EM, 1996. Yellow starthistle, Centaurea solstitialis. In: Rees NE, Quimby PCJr, Piper GL, Coombs EM, Turner CE, Spencer NR, Knutson LV, eds. Biological Control of Weeds in the West. Bozeman, USA: Western Society of Weed Science, USDA/ARS, Montana Department of Agriculture, Montana State University.

Turner CE; Sobhian R; Joley DB; Coombs EM; Piper GL, 1994. Establishment of Urophora sirunaseva (Hering) (Diptera: Tephritidae) for biological control of yellow starthistle in the western United States. Pan-Pacific Entomologist, 70(3):206-211

Tutin TG; Heywood VH; Burges NA; Moore DM; Valentine DH; Walters SM, Webb DA (et al. editors), 1976. Flora Europaea. Volume 4. Plantaginaceae to Compositae (and Rubiaceae). Cambridge, UK: University Press, xxix + 505 + 5pp + 5 maps.

USDA, 1970. Selected Weeds of the United States. Agriculture Handbook No. 366. Washington DC, USA: United States Department of Agriculture, 324-325.

USDA-ARS, 2003. Germplasm Resources Information Network (GRIN). Online Database. Beltsville, Maryland, USA: National Germplasm Resources Laboratory. https://npgsweb.ars-grin.gov/gringlobal/taxon/taxonomysearch.aspx

USDA-NRCS, 2002. The PLANTS Database, Version 3.5. National Plant Data Center, Baton Rouge, USA. http://plants.usda.gov.

USDA-NRCS, 2012. The PLANTS Database. Baton Rouge, USA: National Plant Data Center. http://plants.usda.gov/

Woo I; Swiadon L; Drlik T; Quarles W, 1999. Integrated management of yellow starthistle. IPM Practitioner, 21(7):1-10.

Woods DM, 1998. Endemic and introduced pathogens on yellow starthistle. In: Hoddle MS, ed. Innovation in Biological Control Research. Proceedings of the California Conference on Biological Control, June 10-11, 1998. Berkeley, USA: University of California, 85-87.

Zouhar K, 2002. Centaurea solstitialis. Fire Effects Information System (FEIS) Database. http://www.fs.fed.us/database/feis/plants/weed/index.html.

Distribution Maps

Top of page
You can pan and zoom the map
Save map