Pacific Island Ecosystems at Risk (PIER)


Ceratonia siliqua


RISK ASSESSMENT RESULTS: Low risk, score: 0


Australian/New Zealand Weed Risk Assessment adapted for Hawai‘i.

Research directed by C. Daehler (UH Botany) with funding from the Kaulunani Urban Forestry Program and US Forest Service

Information on Risk Assessments
Original risk assessment

Ceratonia siliqua; carob tree, locust bean

Answer

1.01

Is the species highly domesticated?

y=-3, n=0

y

1.02

Has the species become naturalized where grown?

y=-1, n=-1

y

1.03

Does the species have weedy races?

y=-1, n=-1

n

2.01

Species suited to tropical or subtropical climate(s) (0-low; 1-intermediate; 2-high) – If island is primarily wet habitat, then substitute “wet tropical” for “tropical or subtropical”

See Append 2

1

2.02

Quality of climate match data (0-low; 1-intermediate; 2-high) see appendix 2

1

2.03

Broad climate suitability (environmental versatility)

y=1, n=0

n

2.04

Native or naturalized in regions with tropical or subtropical climates

y=1, n=0

y

2.05

Does the species have a history of repeated introductions outside its natural range? y=-2

?=-1, n=0

y

3.01

Naturalized beyond native range y = 1*multiplier (see Append 2), n= question 2.05

y

3.02

Garden/amenity/disturbance weed y = 1*multiplier (see Append 2)

n=0

y

3.03

Agricultural/forestry/horticultural weed y = 2*multiplier (see Append 2)

n=0

n

3.04

Environmental weed y = 2*multiplier (see Append 2)

n=0

3.05

Congeneric weed y = 1*multiplier (see Append 2)

n=0

n

4.01

Produces spines, thorns or burrs

y=1, n=0

n

4.02

Allelopathic

y=1, n=0

n

4.03

Parasitic

y=1, n=0

n

4.04

Unpalatable to grazing animals

y=1, n=-1

n

4.05

Toxic to animals

y=1, n=0

n

4.06

Host for recognized pests and pathogens

y=1, n=0

n

4.07

Causes allergies or is otherwise toxic to humans

y=1, n=0

n

4.08

Creates a fire hazard in natural ecosystems

y=1, n=0

n

4.09

Is a shade tolerant plant at some stage of its life cycle

y=1, n=0

4.1

Tolerates a wide range of soil conditions (or limestone conditions if not a volcanic island)

y=1, n=0

y

4.11

Climbing or smothering growth habit

y=1, n=0

n

4.12

Forms dense thickets

y=1, n=0

n

5.01

Aquatic

y=5, n=0

n

5.02

Grass

y=1, n=0

n

5.03

Nitrogen fixing woody plant

y=1, n=0

y

5.04

Geophyte (herbaceous with underground storage organs -- bulbs, corms, or tubers)

y=1, n=0

n

6.01

Evidence of substantial reproductive failure in native habitat

y=1, n=0

n

6.02

Produces viable seed.

y=1, n=-1

y

6.03

Hybridizes naturally

y=1, n=-1

6.04

Self-compatible or apomictic

y=1, n=-1

n

6.05

Requires specialist pollinators

y=-1, n=0

n

6.06

Reproduction by vegetative fragmentation

y=1, n=-1

n

6.07

Minimum generative time (years) 1 year = 1, 2 or 3 years = 0, 4+ years = -1

See left

4

7.01

Propagules likely to be dispersed unintentionally (plants growing in heavily trafficked areas)

y=1, n=-1

n

7.02

Propagules dispersed intentionally by people

y=1, n=-1

y

7.03

Propagules likely to disperse as a produce contaminant

y=1, n=-1

y

7.04

Propagules adapted to wind dispersal

y=1, n=-1

n

7.05

Propagules water dispersed

y=1, n=-1

y

7.06

Propagules bird dispersed

y=1, n=-1

n

7.07

Propagules dispersed by other animals (externally)

y=1, n=-1

n

7.08

Propagules survive passage through the gut

y=1, n=-1

y

8.01

Prolific seed production (>1000/m2)

y=1, n=-1

n

8.02

Evidence that a persistent propagule bank is formed (>1 yr)

y=1, n=-1

y

8.03

Well controlled by herbicides

y=-1, n=1

y

8.04

Tolerates, or benefits from, mutilation, cultivation, or fire

y=1, n=-1

y

8.05

Effective natural enemies present locally (e.g. introduced biocontrol agents)

y=-1, n=1

Total score:

0

Supporting data:

Source

Notes

1.01

(1)http://www.ipgri.cgiar.org/publications/pdf/347.pdf (2)http://newcrop.hort.purdue.edu/newcrop/history/lecture04/r_4-3.html

(1)The original distribution of C. siliqua is not clear as it has undergone extensive cultivation since ancient times. Its wild occurrence in the western Mediterranean is doubtful according to Zohary (1973). Spontaneous carobs occur in many places around the western Mediterranean basin but they are regarded as feral derivatives of the fruit crop which probably evolved under domestication.  Zohary (1996) suggested that similarly to most Old World fruit crops, domestication of C. siliqua was based on shifting from sexual reproduction (in thewild) to vegetative propagation (under cultivation). In carob, as in other fruit and nut trees, the shift to vegetative propagation is the cultivator’s solution to theproblem of wide variability which is characteristic of sexual reproduction in crosspollinated plants. In addition, as a predominantly dioecious tree, carob includes about 50% males and 1% hermaphrodites (Condit 1919). Thus spontaneous promising seedlings showing superior features have been empirically selected

1.02

(1)CAB International, (2000) Forestry Compendium Global Module. Wallingford, UK: CAB International. (2)Wunderlin. 1998. Guide to the vascular plants of Florida. University press of Florida, Gainesville.

(1) "cultivated for fodder and widely naturalized"; "It is naturalized and cultivated in Ethiopia and Yemen." (2)NOT naturalized in Florida

1.03

no evidence

2.01

http://www.ipgri.cgiar.org/publications/pdf/347.pdf

The original distribution of C. siliqua is not clear as it has undergone extensive cultivation since ancient times. Hillcoat et al. (1980) suggested its range in the wild included Turkey, Cyprus, Syria, Lebanon, Israel, southern Jordan, Egypt, Arabia, Tunisia and Libya and that it moved westward at an early stage. Carob is believed to have been spread by the Greeks to Greece and Italy and then by the Arabs along the coast of northern Africa into the south and east of Spain, from where it migrated to the south of Portugal and the southeast of France. Its wild occurrence in the western Mediterranean is doubtful according to Zohary (1973). Spontaneous carobs occur in many places around the western Mediterranean basin but they are regarded as feral derivatives of the fruit crop which probably evolved under domestication.

2.02

[although extact origin unknown, possible origins are Mediterranean/sub-tropic]

2.03

(1)CAB International, (2000) Forestry Compendium Global Module. Wallingford, UK: CAB International. (2)http://www.gardenbed.com/C/982.cfm (3)http://www.ecoport.org/

(1)Natural latitude range: Approximate limits north to south: 27N to 45S
Vegetation types: broadleaved evergreen forests; coastal plant communities; sclerophyllous forests
C. siliqua is a heliophilous, thermophilous and xerophilous species of the Mediterranean basin; in Italy it grows from the coast up to 600 m, in the warm Lauretum zone, but it can reach up to 1500-1800 m in North Africa. It has a survival strategy based on avoiding water stress (it grows in countries where the dry season is rarely less than 3 months: in 1999 Sicily suffered a 9 months dry season): the mean annual rainfall of its area ranges from 200 to 850 mm. The typical rainfall regime of the Mediterranean area is the bimodal one (the rainfall seasons are spring and autumn) but this species grows also in countries where the rainfall regime is the winter one. The carob tree can bear low temperatures but can be damaged by frost and snow (damages appears at -5C); the mean maximum temperature of hottest month is about 35C

2.04

CAB International, (2000) Forestry Compendium Global Module. Wallingford, UK: CAB International.

C. siliqua is a native of the Mediterranean basin, its areale includes the northern coasts of Africa (Morocco, Algeria, Tunisia, Cyrenaica, Egypt, Israel, Syria), the southern coasts of Turkey, Cyprus, the Mediterranean and Aegean islands, Greece and Albania, the Mediterranean coasts of Spain. In Italy it grows along the Tyrrhenian and Ionic coasts and along the Adriatic coasts of Puglia. Less frequent in France and Yugoslavia, it is cultivated in the south of Portugal, in Germany and the United Kingdom. Outside Europe, this species has been introduced in India, South Africa and many other African states, Mexico, the United States (Arizona and California), Brazil and Chile, Australia and New Guinea. It is naturalized and cultivated in Ethiopia and Yemen.

2.05

CAB International, (2000) Forestry Compendium Global Module. Wallingford, UK: CAB International.

This species has been introduced in many countries outside its natural distribution (for example South Africa, North and South America, Australia, India) and cultivated for its fruits, which are rich in galactomannans, and as a forage crop.

3.01

(1)CAB International, (2000) Forestry Compendium Global Module. Wallingford, UK: CAB International. (2)Wunderlin. 1998. Guide to the vascular plants of Florida. University press of Florida, Gainesville.

(1) "cultivated for fodder and widely naturalized"; "It is naturalized and cultivated in Ethiopia and Yemen." (2)NOT naturalized in Florida

3.02

http://tncweeds.ucdavis.edu/alert/alrtcera.html

"This species has escaped in Los Angeles Co., the San Jose Hills in Pomona, in San Bernardino Co., and is one of the worst weeds on the University of California, Riverside Botanic Gardens"

3.03

no evidence

3.04

http://tncweeds.ucdavis.edu/alert/alrtcera.html

listed on the weed alert of Nature Conservancy, however the impact of invasion is not clear.

3.05

no evidence

4.01

CAB International, (2000) Forestry Compendium Global Module. Wallingford, UK: CAB International.

no description of these traits

4.02

no evidence

4.03

no evidence

4.04

(1) Kaitho, R. J.; Umunna, N. N.; Nsahlai, I. V.; Tamminga, S.; Bruchem, J. van; Hanson, J.; Wouw, M. van de (1996) Palatability of multipurpose tree species: effect of species and length of study on intake and relative palatability by sheep. Agroforestry Systems, 1996, Vol.33, No.3, pp.249-261, 24 ref.
(2) http://www.ipgri.cgiar.org/publications/pdf/347.pdf

(1) AB: "Flemingia macrophylla, Erythrina abyssinica, Acacia salicina, Acacia coriacea, Albizia schimperana, Ceratonia siliqua, Casuarina glauca and Erythrina burana had poor palatability. These species seem to have little forage value for animals with short-term adaptation periods. "
(2) Carob pods provide fodder for ruminants (Louca and Papas 1973) and nonruminants (Sahle et al. 1992). In the wild, carob shelter, foliage and beans attract browsing animals.

4.05

http://www.ipgri.cgiar.org/publications/pdf/347.pdf

"Carob pods provide fodder for ruminants (Louca and Papas 1973) and nonruminants (Sahle et al. 1992). In the wild, carob shelter, foliage and beans attract browsing animals."

4.06

Awadallah, A. M.; Azab, A. K.; El-Nahal, A. K. M. (1971) Studies on the pomegranate butterfly, Virachola livia (Klug) (Lepidoptera-Rhopalocera:Lycaenidae). Bulletin de la Societe Entomologique d'Egypte, 1971, Vol.54, pp.545-567, 5 ref.

AB: Virachola livia (Klug) is a serious pest of pomegranate fruits in Egypt. An account is given of studies on its distribution and other food-plants there, its bionomics [see also RAE/A 48, p.494-495] and its natural enemies.During a survey in 1963, the Lycaenid was found principally on pomegranate, dates and the green pods of futna (Acacia farnesiana) and sunt (A. arabica (nilotica)). It was also found for the first time on the pods of carob (Ceratonia siliqua) and green pods of broad bean (Vicia faba). [wide host range among legumes?] 

4.07

Rieger, C.; Körner, M.; Kapp, A.; Wedi, B. (2002) Occupational urticaria, angioedema, rhinoconjunctivitis and acute asthma secondary to multiple immediate-type sensitization to food substances. [FT: Beruflich bedingte Urtikaria, Angioödeme, Rhinokonjunktivitis und Asthma bronchiale bei multiplen Typ I-Sensibilisierungen gegenüber Nahrungsmitteln.] Allergologie, 2002, Vol.25, No.7, pp.382-387, 4 ref.

AB: A case of urticaria, angioedema, rhinoconjunctivitis and acute asthma in a 36-year-old man working in a pet food production plant is presented [Germany]. The symptoms that occurred after inhalation of carob bean flour and ingestion of peas and green beans are described. Results of allergy testing, skin prick tests and oral provocation tests for pulses and soyabean flour are discussed. It is suggested that occupationally-acquired sensitization to carob bean flour also caused food intolerance to soyabean flour, peas and green beans due to cross reactivity. [rare case]

4.08

(1)CAB International, (2000) Forestry Compendium Global Module. Wallingford, UK: CAB International. (2)http://cecalaveras.ucdavis.edu/land.htm

(1)an evergreen tree. (2) Listed as a "plant for fire protection"

4.09

(1)CAB International, (2000) Forestry Compendium Global Module. Wallingford, UK: CAB International. (2)http://www.ecoport.org/ (3)http://members.frys.com/~bpmosley/Cer_sil.HTM (4)http://selectree.cagr.calpoly.edu/treedetail.lasso?KeyValue=306

(1)C. siliqua is a heliophilous tree which can tolerate shading conditions, especially when it is young; however, light conditions are required for a vigorous growth.(2)It thrives in full sunlight.(3)Full sun (4) Full Sun / Partial Shade

4.1

CAB International, (2000) Forestry Compendium Global Module. Wallingford, UK: CAB International.

C. siliqua is quite indifferent to the substratum; it can grow on a great range of soil types, even on compact clay soils. Sometimes it is able to climb to rocky hillsides, growing in stony places unsuited to other plants. It avoids only acid soils and those which are seasonally waterlogged.
Descriptors
- Soil texture: light; medium; heavy
- Soil drainage: free
- Soil reaction: neutral; alkaline
- Special soil tolerances: infertile
- Soil types: alkaline soils; arid soils; calcareous soils; clay soils; acid soils; gravelly soils; limestone soils; sandstone soils; sandy soils; volcanic soils

4.11

CAB International, (2000) Forestry Compendium Global Module. Wallingford, UK: CAB International.

It is a small- to medium-size (8-17 m tall) evergreen tree

4.12

no evidence

5.01

terrestrial

5.02

tree; Fabaceae

5.03

CAB International, (2000) Forestry Compendium Global Module. Wallingford, UK: CAB International.

"fix nitrogen"

5.04

tree

6.01

CAB International, (2000) Forestry Compendium Global Module. Wallingford, UK: CAB International.

C. siliqua is a native of the Mediterranean basin, cultivated for fodder and widely naturalized

6.02

CAB International, (2000) Forestry Compendium Global Module. Wallingford, UK: CAB International.

"Carob stand establishment is usually made using direct sowing"

6.03

no evidence

6.04

(1) CAB International, (2000) Forestry Compendium Global Module. Wallingford, UK: CAB International.
(2) http://www.ipgri.cgiar.org/publications/pdf/347.pdf (3)http://www.desert-tropicals.com/Plants/Fabaceae/Ceratonia_siliqua.html

(1) The carob is a dioecious tree. In stand establishments, female trees must be planted next to male trees, or a male branch can be grafted on a female tree, to provide the necessary pollen.
(2) "In addition, as a predominantly dioecious tree, carob includes about 50% males and 1% hermaphrodites."; "Hermaphrodites have a special value provided that they are self-fertile and/or cross-compatible" (3)Carobs can be male, female or hermaphrodite. Only the female trees produce brown leathery pods (up to 1 foot long) 11 months after pollination.

6.05

Ortiz, P. L.; Arista, M.; Talavera, S. (1996) Nectar production and frequency of pollinators in Ceratonia siliqua L. (Caesalpiniaceae). [FT: Producción de néctar y frequencia de polinizadores en Ceratonia siliqua L. (Caesalpiniaceae).] Anales del Jardín Botánico de Madrid, 1996, Vol.54, No.1, pp.540-546, 23 ref.

AB: "The main pollinators were of the Hymenoptera (chiefly Apis mellifera and Vespidae) and the Diptera."

6.06

CAB International, (2000) Forestry Compendium Global Module. Wallingford, UK: CAB International.

It has a good capacity to produce suckers [no evidence of root suckers, but basal suckers]

6.07

http://www.ipgri.cgiar.org/publications/pdf/347.pdf

In plantations located in marginal areas, the nonbearing period is long, from 6 to 8 years, while in others, where the conditions are better, cropping starts 3 or 4 years after budding. The seedling stocks should be budded 1 year after germination, in the nursery, or 2 years from germination, after planting in the orchard.

7.01

no evidence

7.02

CAB International, (2000) Forestry Compendium Global Module. Wallingford, UK: CAB International.

This species has been introduced in many countries outside its natural distribution (for example South Africa, North and South America, Australia, India) and cultivated for its fruits, which are rich in galactomannans, and as a forage crop.

7.03

http://tncweeds.ucdavis.edu/alert/alrtcera.html

"In urban areas, carob seeds in mulch made from C. siliqua street trees readily germinates" [also, the pod is edible produce]

7.04

no evidence

7.05

http://www.losbanos.org/web/d/pubservices/parks/treecity/trees/Carob.html

C. siliqua rarely invades undisturbed habitats but escapes easily along washes and other moist areas.

7.06

no evidence

7.07

no evidence

7.08

(1) http://tncweeds.ucdavis.edu/alert/alrtcera.html
(2) El-Shatnawi, M. K. J.; Ereifej, K. I. (2001) Chemical composition and livestock ingestion of carob (Ceratonia siliqua L.) seeds. Journal of Range Management, 2001, Vol.54, No.6, pp.669-673, 33 ref.

(1) Coyotes frequently consume carob fruits and disperse the seeds in their scat. In Israel, the fruits are fed upon by fruit bats that eject (spit out) the seeds in pellets, which disperses them away from the tree. Ejected seeds germinate as readily as the seeds taken directly from the fruit.
(2) AB: Pods and seeds from carob (Ceratonia siliqua ) trees growing in Ajloun Mountainous forests and rangelands in Jordan were analysed for their proximate analysis, Ca and P contents, and also the effects of ingestion of seeds by sheep and goat on the germination were investigated. Germination percentages for seeds that were ingested by sheep were 73.5, 61.8, 39.3, and 0.0% for ingestion periods of 24, 48, 72, and 96 hours, respectively; whereas, it was 56.8, 79.9, 50.1, 13.7, and 1.1% for seeds dispersed from goat after 24, 48, 72, 96, and 120 hours.

8.01

(1) CAB International, (2000) Forestry Compendium Global Module. Wallingford, UK: CAB International.
(2) Batlle, I.; Tous, J. (1998) 'Rojal' carob. Fruit Varieties Journal, 1998, Vol.52, No.1, pp.51-52, 3 ref.

(1) The fruit is a legume, linear-oblong, 10-12 cm long and 2 cm large, dark brown, compressed and indehiscent, with 12-16 seeds inside. The density of plantations can range from 25 to 100 plants/ha. Fruit yields of 10 tons/ha/year (mean) are produced, mostly from Spain, Italy and Portugal. Irrigated plantations can reach higher yields (ANPA, 1998).
(2) Seed yield is approx equal to 10% and seed weight is 0.2 g.
[10000kg/10000m2 = 1 kg/ m2 = 100g seed = 500 seeds ]

8.02

CAB International, (2000) Forestry Compendium Global Module. Wallingford, UK: CAB International.

These are brown, flattened on one face, hard and impermeable to water and gas, so that the seed will not germinate unless the seed coat is scarified. C. siliqua has a hard seed, with a waterproof seed coat that must be scarified in advance; this is done using mechanical scarifiers, sulphuric acid or hot water. Seeds with a 5-10% moisture content can be stored for a long time.

8.03

Bosco, G. F. del (1974) Chemical weed control in tree crops: advantages and disadvantages. Informatore Agrario, 1974, Vol.30, No.34, pp.16857-16858, 9 ref.

AB: "Olives and carobs are very sensitive to uracil herbicides. "

8.04

CAB International, (2000) Forestry Compendium Global Module. Wallingford, UK: CAB International.

It has a good capacity to produce suckers, so it is suited for coppicing.

8.05

no evidence


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