Pacific Island Ecosystems at Risk (PIER)


Euphorbia amygdaloides var. 'Efanthia'


RISK ASSESSMENT RESULTS: High risk, score: 12


Australian/New Zealand Weed Risk Assessment adapted for Hawai‘i.
Information on Risk Assessments
Original risk assessment
  Euphorbia amygdaloides variety ‘Efanthia’ Improved. (Wood spurge) - Euphorbiaceae Answer Score
1.01 Is the species highly domesticated? n 0
1.02 Has the species become naturalized where grown? n  
1.03 Does the species have weedy races? 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” 1  
2.02 Quality of climate match data (0-low; 1-intermediate; 2-high)                 see appendix 2 2  
2.03 Broad climate suitability (environmental versatility) y 1
2.04 Native or naturalized in regions with tropical or subtropical climates n 0
2.05 Does the species have a history of repeated introductions outside its natural range?  y=-2 ?  
3.01 Naturalized beyond native range         y = 1*multiplier (see Append 2), n= question 2.05 y 2
3.02 Garden/amenity/disturbance weed                              y = 1*multiplier (see Append 2) y 2
3.03 Agricultural/forestry/horticultural weed                         y = 2*multiplier (see Append 2) n 0
3.04 Environmental weed                                                     y = 2*multiplier (see Append 2) n 0
3.05 Congeneric weed                                                          y = 1*multiplier (see Append 2) y 2
4.01 Produces spines, thorns or burrs n 0
4.02 Allelopathic n 0
4.03 Parasitic n 0
4.04 Unpalatable to grazing animals y 1
4.05 Toxic to animals y 1
4.06 Host for recognized pests and pathogens n 0
4.07 Causes allergies or is otherwise toxic to humans y 1
4.08 Creates a fire hazard in natural ecosystems n 0
4.09 Is a shade tolerant plant at some stage of its life cycle y 1
4.1 Tolerates a wide range of soil conditions (or limestone conditions if not a volcanic island) y 1
4.11 Climbing or smothering growth habit n 0
4.12 Forms dense thickets n 0
5.01 Aquatic n 0
5.02 Grass n 0
5.03 Nitrogen fixing woody plant n 0
5.04 Geophyte (herbaceous with underground storage organs -- bulbs, corms, or tubers) n 0
6.01 Evidence of substantial reproductive failure in native habitat n 0
6.02 Produces viable seed. y 1
6.03 Hybridizes naturally y 1
6.04 Self-compatible or apomictic    
6.05 Requires specialist pollinators n 0
6.06 Reproduction by vegetative fragmentation y 1
6.07 Minimum generative time (years)                 1 year = 1, 2 or 3 years = 0, 4+ years = -1 2 0
7.01 Propagules likely to be dispersed unintentionally (plants growing in heavily trafficked areas) n -1
7.02 Propagules dispersed intentionally by people y 1
7.03 Propagules likely to disperse as a produce contaminant n -1
7.04 Propagules adapted to wind dispersal y 1
7.05 Propagules water dispersed n -1
7.06 Propagules bird dispersed n -1
7.07 Propagules dispersed by other animals (externally) n -1
7.08 Propagules survive passage through the gut n -1
8.01 Prolific seed production (>1000/m2) y 1
8.02 Evidence that a persistent propagule bank is formed (>1 yr)    
8.03 Well controlled by herbicides    
8.04 Tolerates, or benefits from, mutilation, cultivation, or fire    
8.05 Effective natural enemies present locally (e.g. introduced biocontrol agents)    
  Total score:   12

Supporting data:

Notes

Reference

1.01

No evidence

1.02

No evidence

1.03

Several horticultureal varieties known like ephanthia, purpurea and robbiae but no evidence of them being weedy.

(1)http://www.provenwinners.com/plants/detail.cfm?photoID=5858&doSearch=1&viewType=Fall& (2)http://www.paghat.com/euphorbiapurpurea.html (3)http://www.crocus.co.uk/plantingideas/home/?ContentType=Plant_Card&ClassID=2780

2.01

(1)Wood Spurge is a European plant in the genus Euphorbia. (2)Native to Europe (Hungary) (3)British native. (4) Britain. Europe. S.W. Asia. (5) 'The general range of Euphorbia amygdaloides in Europe and Asia is characteristic of subatlantic-submediterranean distribution type.'

(1)http://en.wikipedia.org/wiki/Euphorbia_amygdaloides (2)Papp, N. 2004. Nectar and nectary studies on seven Euphorbia species. Acta Botanica Hungarica. 46 (1/2). 225-234. (3)Paterson Allen. 1981. Plants for shade. J.M. Dent and Sons Ltd. London. Page.

2.02

Introduced to New Zealand.

2.03

(1) E. amygdaloides efanthia- Zone(s) 4-11
(2)For E. amygdaloides. USDA Zone 6a: to -23.3° C (-10° F)
USDA Zone 6b: to -20.5° C (-5° F)
USDA Zone 7a: to -17.7° C (0° F)
USDA Zone 7b: to -14.9° C (5° F)
USDA Zone 8a: to -12.2° C (10° F)
USDA Zone 8b: to -9.4° C (15° F)

(1)http://www.provenwinners.com/plants/detail.cfm?photoID=5858&doSearch=1&viewType=Fall& (2)http://davesgarden.com/pf/go/152/index.html

2.04

Native to temperate regions and no evidence of naturalization in the tropics. (1)Wood Spurge is a European plant in the genus Euphorbia. (2)Origin: Africa (3)Native to Europe (Hungary) (4)British native.

(1)http://en.wikipedia.org/wiki/Euphorbia_amygdaloides (2)http://www.desert-tropicals.com/Plants/Euphorbiaceae/Euphorbia_amygdaloides.html (3)Papp, N. 2004. Nectar and nectary studies on seven Euphorbia species. Acta Botanica Hungarica. 46 (1/2). 225-23

2.05

Introduced to New Zealand.[No other evidence of introduction].

3.01

Naturalized in New Zealand

http://nzflora.landcareresearch.co.nz/default.aspx?selected=NameDetails&TabNum=0&NameId=E2694B35-19BD-4C2F-91CA-6386EC03D120

3.02

A weed along roadsides in New Zealand. Also collected from gardens - growing among cultivated plants in New Zealand.

http://www.hear.org/gcw/html/autogend/species/7987.HTM

3.03

No evidence

3.04

No evidence

3.05

(1)E. cyathophora. - 'In Fiji, an abundantly naturalized weed occurring from near sea level to about 100 m in clearings, along roadsides and trails, and in coconut plantations and canefields; it is often abundant in coastal areas, frequently on sandy beaches (Smith, 1981). In Niue, "one of the commonest weeds of waste places all round the perimeter of the island. It is also found rather less frequently through the interior, in old plantations and by the roadside." (Sykes, 1970) "Occasional in disturbed places on Niue, but more of an escaped ornamental in Tonga and Samoa" (Whistler, 1988). In New Caledonia, "localement comun, surtout en arrière-plage" (MacKee, 1994). Arid lowlands in the Galápagos Islands (McMullen, 1999).'

http://www.hear.org/pier/species/euphorbia_cyathophora.htm

4.01

No evidence of such characteristics.

4.02

No evidence

4.03

No evidence

4.04

 Probably yes - (1)Avoided by roe deers - 'The development of feeding behaviour and recognition of preferred and non-preferred plant species were studied in 9 roe deer (Capreolus capreolus) fawns separated from their mothers 3 days after birth. From age 15 days to 1.5 months they were offered species always avoided by roe deer (Arum italicum, A. maculatum and Euphorbia amygdaloides), species normally avoided but which could be eaten occasionally (Primula veris, Ajuga reptans and Viburnum lantana) and preferred species (Carpinus betulus and Acer monspessulanum). Feeding behaviour of the fawns was compared with that of 8 adults living in a forested enclosure. Fawns displayed selectivity towards the different plant species from their first contact, probably in response to taste. Thereafter, consumption of the 2 preferred species rapidly increased, while use of the others remained at very low levels. Fawn selectivity was similar to that of the adults from the third contact with the plant species (before they were one month old). This learning processes appeared to be based on the association between effects of eating the different plant species (satiation or illness) and taste and smell. Therefore, an effective repellent must have a taste and smell associated with avoided plants, as well the same effects on ingestion.' (2)TOXICITY RATING: Moderate. Spurges are highly unpalatable, and are rarely consumed in quantities sufficient to cause serious toxicity, but are very irritating upon contact.
ANIMALS AFFECTED: Any animal consuming spurge or coming in contact with the sap may be affected.
DANGEROUS PARTS OF PLANT: All parts.
CLASS OF SIGNS: Gastrointestinal irritation, dermal and ocular irritation, poor doer, weakness.

(1)Verheyden-Tixier, H.; Duncan, P.; Maizeret, C. 1998. Selective feeding behaviour in roe deer: learning and recognition of plant species, and effects on the development of repellents / Comportement de selection alimentaire chez le chevreuil: apprentissa

4.05

Based upon characteristics of the genus Euphorbia in general - TOXICITY RATING: Moderate. Spurges are highly unpalatable, and are rarely consumed in quantities sufficient to cause serious toxicity, but are very irritating upon contact.
ANIMALS AFFECTED: Any animal consuming spurge or coming in contact with the sap may be affected.
DANGEROUS PARTS OF PLANT: All parts.
CLASS OF SIGNS: Gastrointestinal irritation, dermal and ocular irritation, poor doer, weakness.

http://www.vet.purdue.edu/depts/addl/toxic/plant37.htm

4.06

No evidence of associated pests of pathogens.

4.07

(1)Danger: All parts of plant are poisonous if ingested (2) The milky juice of the plant is toxic and it can cause irritation on contact with the skin. (3)TOXICITY RATING: Moderate. Spurges are highly unpalatable, and are rarely consumed in quantities sufficient to cause serious toxicity, but are very irritating upon contact.DANGEROUS PARTS OF PLANT: All parts. CLASS OF SIGNS: Gastrointestinal irritation, dermal and ocular irritation, poor doer, weakness.

(1)http://davesgarden.com/pf/go/152/index.html (2)http://en.wikipedia.org/wiki/Euphorbia_amygdaloides (3)http://www.vet.purdue.edu/depts/addl/toxic/plant37.htm

4.08

Probably not - evergreen herbaceous plant, no known to form dense thickets.

4.09

(1)Sun Exposure: Sun to Partial Shade (2)Described in the bood of shade tolerant plants.

(1)http://davesgarden.com/pf/go/152/index.html (2)Paterson Allen. 1981. Plants for shade. J.M. Dent and Sons Ltd. London. Page. 141.

4.1

For E. amygdaloides variety robbiae - Soil type: Acidic, Chalky/alkaline, Moist, Well-drained/light.

http://www.bbc.co.uk/gardening/plants/plant_finder/plant_pages/305.shtml

4.11

(1)herbaceous perennial (2) 14 to 20 inches tall - herbaceous evergreen foliage.

(1)http://web1.msue.msu.edu/imp/modzz/00002173.html (2)http://www.provenwinners.com/plants/detail.cfm?photoID=5858&doSearch=1&viewType=Fall&

4.12

No evidence

5.01

5.02

5.03

No evidence

5.04

No evidence

6.01

No evidence

6.02

(1Wood Spurge is a European plant in the genus Euphorbia. It reproduces both from seeds and root runners that spread underground then sprout new plants. (2) 'Propagation is simplest from seed.'

(1)http://en.wikipedia.org/wiki/Euphorbia_amygdaloides (2)Turner, R. 1995. Euphorbias a gardners guide. Timber Press. Portland. Oregon. Pg 79

6.03

(1)Euphorbia X martinii is a natural hybrid between Mediterranean spurge and wood spurge (E. amygdaloides). It is smaller, to 2' (0.6 m) tall and has dark red nectar glands on the flower bracts which are arranged in elongate clusters 4-5 in (10.2-12.7 cm)

(1)http://www.floridata.com/main_fr.cfm?state=ref_search&viewsrc=lists/search.cfm (2)Smith, R A. 1985. Two new Euphorbia hybrids. Kew Bulletin. 40(2):445-446. (3)Turner, R. 1995. Euphorbias a gardners guide. Timber Press. Portland. Oregon.

6.04

Don’t know

6.05

Floral head 5(8)-rayed umbel, twice forked, with 4-9(16) axillary rays, also twice forked, floral leaves pale greenish, in pairs alomost fused together in saucer-like fashion, each half rought circular or kidney shaped, 15-20 mm across. See photo on page 97. [Probably not - flower shape does not suggest specialized pollination to occur].

Turner, R. 1995. Euphorbias a gardners guide. Timber Press. Portland. Oregon. Pg 79.

6.06

Wood Spurge is a European plant in the genus Euphorbia. It reproduces both from seeds and root runners that spread underground then sprout new plants.

http://en.wikipedia.org/wiki/Euphorbia_amygdaloides

6.07

Flowering stems biennial.

Turner, R. 1995. Euphorbias a gardners guide. Timber Press. Portland. Oregon.

7.01

No evidence that the seeds have any means of attachment by means of which it could be introduced unintentionally. No evidence the species grows in wet muddy areas and the seeds could be transported unintenionally through mud.

 

7.02

Probably yes - a desirable horticulural plant. 'An improved variety featuring evergreen, smooth foliage and burgundy cool-weather color. Bushy, compact habit, drooping and non-curling leaves.

http://www.provenwinners.com/plants/detail.cfm?photoID=5858&doSearch=1&viewType=Fall&

7.03

No evidence of the species being grown near produce plants. No evidence of the species being traded as cut flowers with seeds on them.

 

7.04

Fruit is a capsule - flattened ovoid, 3-4, (2.5)3-4 mm, with three deep furrows, minutely pitted or dotted. Seed dark bluish grey to black, 2-2.5mm, ovoid, smooth, with small caruncle. [Relatively small seeds with no particular adaptation for dispersal by wind, but could be blown around by wind].

Turner, R. 1995. Euphorbias a gardners guide. Timber Press. Portland. Oregon. Pg 79

7.05

Probably not - no evidence that the species grows near water bodies in the native habiatat.

Turner, R. 1995. Euphorbias a gardners guide. Timber Press. Portland. Oregon. Pg 79

7.06

Fruit is a capsule - flattened ovoid, 3-4, (2.5)3-4 mm, with three deep furrows, minutely pitted or dotted. Seed dark bluish grey to black, 2-2.5mm, ovoid, smooth, with small caruncle. [Probably not - fruit is a capsule with small seeds].

Turner, R. 1995. Euphorbias a gardners guide. Timber Press. Portland. Oregon. Pg 79

7.07

No evidence the the seeds have any means of attachment.

Turner, R. 1995. Euphorbias a gardners guide. Timber Press. Portland. Oregon. Pg 79

7.08

No evidence of ingestion

Turner, R. 1995. Euphorbias a gardners guide. Timber Press. Portland. Oregon. Pg 79

8.01

Fruit is a capsule - flattened ovoid, 3-4, (2.5)3-4 mm, with three deep furrows, minutely pitted or dotted. Seed dark bluish grey to black, 2-2.5mm, ovoid, smooth, with small caruncle. [Probably yes - relative small seeds of a biennial plant].

Turner, R. 1995. Euphorbias a gardners guide. Timber Press. Portland. Oregon. Pg 79

8.02

No evidence regarding seed bank.

8.03

No evidence that the species is being controlled for.

8.04

Don’t know

8.05

Don’t know

 


Need more info? Have questions? Comments? Information to contribute? Contact PIER!


[ Return to PIER homepage ] [Risk assessment page]


This page created 26 December 2006