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

Olea europaea

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

y

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

n

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

y

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

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

y

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

n

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

y

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

6

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

n

7.04

Propagules adapted to wind dispersal

y=1, n=-1

n

7.05

Propagules water dispersed

y=1, n=-1

n

7.06

Propagules bird dispersed

y=1, n=-1

y

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

n

Total score:

5

Source

Notes

1.01

(1)Baldoni, L.; Pellegrini, M.; Mencuccini, M.; Angiolillo, A.; Mulas, M. (2000) Genetic relationships among cultivated and wild olives revealed by AFLP markers. Acta Horticulturae, 2000, No.521, pp.275-283 (asbstract) (2) Gilman E.F. 1996. Horticopia-Trees, shrubs and groundcovers. Desops, Ltd.

(1) Some 45 wild olive (Olea europaea ) genotypes of different origin were compared with 45 widely cultivated varieties by amplified fragment length polymorphism. Varieties and wild genotypes clustered separately. Two types of wild olives were recognized: one showing a higher relatedness with the cultivars and a second one with a molecular profile clearly different from both cultivated and other wild olives. Samples from Sicily, Sardinia and Corsica belonged to the first type while the wild plants collected in Apulia showed a higher range of variability and, for some of them, the belonging to the 'oleaster' form of Olea europaea was hypothesized. (2)There are some "nonfruiting" selections available at some nurseries.

1.02

(1) Spennemann, D. H. R.; Allen, L. R. (2000) From cultivar to weed: the spread of olives in Australia. Olivae, 2000, No.82, pp.44-46 (abstract) (2) Wagner, Warren L., Derral R. Herbst and S.H. Sohmer. 1990. Manual of the flowing plants of Hawai'i. University of Hawai'i Press, Honolulu. p.992.

(1) "Olives were introduced into Australia in 1800. Several attempts at a commercial olive industry have resulted in substantial orchards being left to run feral once the orchards were found to be unprofitable. These orchards have become the foci of dispersal by birds and some mammals, resulting in self-seeding olives invading native bushland. As the new generations of feral olives possess smaller drupes, they can be dispersed by a greater range of vectors." (2) naturalized in Hawaii

1.03

see above

2.01

Gilman E.F. 1996. Horticopia-Trees, shrubs and groundcovers. Desops, Ltd.

native to warm Mediterranean region

2.02

2.03

(1)Hawaiian Alien Plants Studies. University of Hawaii, Botany Department (http://www.botany.hawaii.edu/faculty/cw_smith/ole_eur.htm) (2) Plant Master 5.5. California Edition.1999. Acacia Software, Westlake Village, California.

(1)This shrubby, evergreen tree forms dense, monotypic thickets between 500-1500 m elevation. (2) USDA Zones 9-10, New USDA Temp Zones 9b-11a

2.04

Spennemann, D. H. R.; Allen, L. R. (2000) From cultivar to weed: the spread of olives in Australia. Olivae, 2000, No.82, pp.44-46 (abstract)

"Olives were introduced into Australia in 1800. Several attempts at a commercial olive industry have resulted in substantial orchards being left to run feral once the orchards were found to be unprofitable. These orchards have become the foci of dispersal by birds and some mammals, resulting in self-seeding olives invading native bushland. As the new generations of feral olives possess smaller drupes, they can be dispersed by a greater range of vectors."

2.05

(1) Spennemann, D. H. R.; Allen, L. R. (2000) From cultivar to weed: the spread of olives in Australia. Olivae, 2000, No.82, pp.44-46 (abstract) (2) Wagner, Warren L., Derral R. Herbst and S.H. Sohmer. 1990. Manual of the flowing plants of Hawai'i. University of Hawai'i Press, Honolulu. p.992. (3) Goldhamer, D. A. (1999) Regulated deficit irrigation for California canning olives. Acta Horticulturae, 1999, No.474, pp.369-372 (abstract)

(1) "Olives were introduced into Australia in 1800. (2) naturalized in Hawaii (3) California

3.01

Spennemann, D. H. R.; Allen, L. R. (2000) From cultivar to weed: the spread of olives in Australia. Olivae, 2000, No.82, pp.44-46 (abstract)

"Olives were introduced into Australia in 1800. Several attempts at a commercial olive industry have resulted in substantial orchards being left to run feral once the orchards were found to be unprofitable. These orchards have become the foci of dispersal by birds and some mammals, resulting in self-seeding olives invading native bushland. As the new generations of feral olives possess smaller drupes, they can be dispersed by a greater range of vectors."

3.02

no evidence

3.03

no evidence

3.04

Spennemann, D. H. R.; Allen, L. R. (2000) From cultivar to weed: the spread of olives in Australia. Olivae, 2000, No.82, pp.44-46 (abstract) 2)http://www.ssn.flinders.edu.au/geog/people/Honours%201999/pp/crossman/index.htm 3)http://www.boprc.govt.nz/www/green/weed88.htm 4)http://www.botany.hawaii.edu/faculty/carr/ole_eur.htm

"Olives were introduced into Australia in 1800. Several attempts at a commercial olive industry have resulted in substantial orchards being left to run feral once the orchards were found to be unprofitable. These orchards have become the foci of dispersal by birds and some mammals, resulting in self-seeding olives invading native bushland. As the new generations of feral olives possess smaller drupes, they can be dispersed by a greater range of vectors." 2)The impact of European Olive (Olea europaea) invasion into the Greybox (Eucalyptus microcarpa) woodland community in South Australia -- describes problems 3)Olea europaea subsp. africana invades coastal natural areas in New Zealand 4)This shrubby, evergreen tree forms dense, monotypic thickets between 500-1500 m elevation.The major infestations are at Waimea, Hawai'i and 'Ainahou, Hawai'i Volcanoes National Park.

3.05

no evidence

4.01

Wagner, Warren L., Derral R. Herbst and S.H. Sohmer. 1990. Manual of the flowing plants of Hawai'i. University of Hawai'i Press, Honolulu. p.992.

4.02

Hu, Q. H. (1985) Effects of coumarin on some physiological processes in boron-deficient plants. Plant Physiology Communications, 1985, No.No.6, pp.25-26 (abstract)

" At 1-50 p.p.m., coumarin extracted from B-deficient olive cv. Frantotio plants had inhibitory effects on barley seed germination and seedling, root and leaf growth, to an extent varying with the concn. Peroxidase and amylase activities were significantly inhibited in barley seedlings cultured on filter paper soaked in 25 p.p.m. coumarin solution. " --These are very low concentrations, nevertheless, effect under natural conditions is unknown.

4.03

4.04

Sfougaris, A. I.; Nastis, A. S.; Papageorgiou, N. K. (1996). Food resources and quality for the introduced Cretan wild goat or agrimi Capra aegagrus cretica on Atalandi Island, Greece, and implications for ecosystem management. Biological Conservation, 1996, Vol.78, No.3, pp.239-245 (abstract)

A study of seasonal feed availability and quality for Cretan wild goat or agrimi, Capra aegagrus cretica , introduced on Atalandi Island, Greece, was conducted during 1988-89. The major portion of available forage consisted of Olea europaea var. sylvestris , Pistacia lentiscus and Cistus spp. The first two species are the main feed resources in late summer and early autumn, the critical period for agrimi nutrition, and the only species with CP content exceeding the maintenance requirements of agrimi.

4.05

Sfougaris, A. I.; Nastis, A. S.; Papageorgiou, N. K. (1996). Food resources and quality for the introduced Cretan wild goat or agrimi Capra aegagrus cretica on Atalandi Island, Greece, and implications for ecosystem management. Biological Conservation, 1996, Vol.78, No.3, pp.239-245 (abstract)

A study of seasonal feed availability and quality for Cretan wild goat or agrimi, Capra aegagrus cretica , introduced on Atalandi Island, Greece, was conducted during 1988-89. The major portion of available forage consisted of Olea europaea var. sylvestris , Pistacia lentiscus and Cistus spp. The first two species are the main feed resources in late summer and early autumn, the critical period for agrimi nutrition, and the only species with CP content exceeding the maintenance requirements of agrimi.

4.06

no evidence

4.07

no evidence

4.08

no evidence

4.09

4.1

(1) Gilman E.F. 1996. Horticopia-Trees, shrubs and groundcovers. Desops, Ltd. (2)Plant Master 5.5. California Edition.1999. Acacia Software, Westlake Village, California.

(1) sandy, loamy, well drained; acidic-alkaline; (2) sandy, loam, rocky; neutral, basic; alkaline tolerant

4.11

Wagner, Warren L., Derral R. Herbst and S.H. Sohmer. 1990. Manual of the flowing plants of Hawai'i. University of Hawai'i Press, Honolulu. p.992.

4.12

Hawaiian Alien Plants Studies. University of Hawaii, Botany Department (http://www.botany.hawaii.edu/faculty/cw_smith/ole_eur.htm)

This shrubby, evergreen tree forms dense, monotypic thickets between 500-1500 m elevation.

5.01

Wagner, Warren L., Derral R. Herbst and S.H. Sohmer. 1990. Manual of the flowing plants of Hawai'i. University of Hawai'i Press, Honolulu. p.992.

5.02

Wagner, Warren L., Derral R. Herbst and S.H. Sohmer. 1990. Manual of the flowing plants of Hawai'i. University of Hawai'i Press, Honolulu. p.992.

5.03

Wagner, Warren L., Derral R. Herbst and S.H. Sohmer. 1990. Manual of the flowing plants of Hawai'i. University of Hawai'i Press, Honolulu. p.992.

5.04

Wagner, Warren L., Derral R. Herbst and S.H. Sohmer. 1990. Manual of the flowing plants of Hawai'i. University of Hawai'i Press, Honolulu. p.992.

6.01

no evidence

6.02

27.0% of dispersed seeds produced seedlings

6.03

no evidence

6.04

(1) Dimassi, K.; Therios, I.; Balatsos, A. (1999) The blooming period and self-fruitfulness in twelve Greek and three foreign olive cultivars. Acta Horticulturae, 1999, No.474, pp.275-278 (abstract)
(2) Ateyyeh, A. F.; Stösser, R.; Qrunfleh, M. (2000) Reproductive biology of the olive (Olea europaea L.) cultivar 'Nabali Baladi'. Journal of Applied Botany, 2000, Vol.74, No.5/6, pp.255-270 (abstract)

(1) Among the 6 cultivars tested, Adramitini, Cordal and Kothreiki were self-compatible, while Chondrolia Chalkidikis, Karydolia and Manzanillo were partially self-incompatible. (2) From the results, it is suggested that Nabali Baladi can be considered a partially self-compatible cultivar. Its self-incompatibility is gametophytic.

6.05

no evidence

6.06

no evidence

6.07

Roecklein, JC & Leung PS (1987) A Profile of Economic Plants. Transaction Inc., New Brunswick and New Jersey. P. 348

6 years to fruit

7.01

no evidence

7.02

grown for fruit and ornamental

7.03

no evidence

7.04

no evidence

7.05

no evidence

7.06

Feral olives (Olea europaea ) as future woody weeds in Australia: a review. (abstract)

This paper reviews the literature on the activity of vertebrate (principally avian) olive predators and their potential as vectors for spreading this plant into Australian remnant bushland.

7.07

no evidence

7.08

bird dispersal

8.01

Alcántara, J. M.; Rey, P. J.; Sánchez-Lafuente, A. M.; Valera, F. (2000) Early effects of rodent post-dispersal seed predation on the outcome of the plant-seed disperser interaction. Oikos, 2000, Vol.88, No.2, pp.362-370 (abstract)

Seed density ranged from 0 seeds/m2 in open areas to 93.2 seeds/m2 under O. europaea .

8.02

Crisosto, C. Sutter, E.G. (1985) Role of the endocarp in `Manzanillo' olive seed germination. J. Amer. Soc. Hort. Sci. v.110 no.1 p.50-52 . 1985
Gave endocarp severe treatments to test its effect on germination. Endocarp inhibited germ. in stratified as well as unstrat. seed. Removing endocarp lead to high germination percent, but only when completely removed or when radicle end was removed. The endocarp did not inhibit germination by preventing imbibition since water uptake occurred in the seed through the untreated endocarp and through the clipped cotyledon end. The endocarp also did not contain water-soluble inhibitors that prevent germination. Rather, it seemed to inhibit through mechanical resistance. Also argue that oxyen was not prevented when endocarp ends were clipped off. Since both scarification and stratification were necessary to get germination there is physical and physiological dormancy.

Gave endocarp severe treatments to test its effect on germination. Endocarp inhibited germ. in stratified as well as unstrat. seed. Removing endocarp lead to high germination percent, but only when completely removed or when radicle end was removed. The endocarp did not inhibit germination by preventing imbibition since water uptake occurred in the seed through the untreated endocarp and through the clipped cotyledon end. The endocarp also did not contain water-soluble inhibitors that prevent germination. Rather, it seemed to inhibit through mechanical resistance. Also argue that oxyen was not prevented when endocarp ends were clipped off. Since both scarification and stratification were necessary to get germination there is physical and physiological dormancy.

8.03

http://www.bushcare.org.au/WeedControl.htm

no evidence of problem, Spray seedling glyphosate 1:75-100, cut stump/driII/axe/inject undiluted (G)

8.04

Shelden, M.; Sinclair, R. (2000). Water relations of feral olive trees (Olea europaea ) resprouting after severe pruning. Australian Journal of Botany, 2000, Vol.48, No.5, pp.639-644 (abstract)

Water relations of feral olives (Olea europaea L.) were studied on a location in the Mt Lofty Ranges, South Australia, in 1997. In spring (October-November), 6 months before the study commenced, an area of trees had been cut back to stumps as part of an eradication project. The stumps resprouted vigorously over summer, similarly to regrowth seen following wildfire.

8.05

forming dense stands in hawaii (Cliff Smith's webpage)