Pacific Island Ecosystems at Risk (PIER)


Eucalyptus globulus


RISK ASSESSMENT RESULTS: High risk, score: 10


Australian/New Zealand Weed Risk Assessment adapted for Hawai‘i.
Information on Risk Assessments
Original risk assessment

Eucalyptus globulus Labill. Common name - blue gum, southern blue gum. Synonyms- Eucalyptus bicostata Maiden et al., Eucalyptus globulus var. saint-johnii, Eucalyptus maidenii F. Muell., Eucalyptus pseudoglobulus Naudin ex Maiden, Eucalyptus saint-johnii (R. T. Baker). Family - Myrtaceae.

Answer

Score

1.01

Is the species highly domesticated? (If answer is 'no' then go to question 2.01)

n

0

1.02

Has the species become naturalized where grown?

1.03

Does the species have weedy races?

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

y

1

2.05

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

y

3.01

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

y

1

3.02

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

n

0

3.03

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

n

0

3.04

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

y

2

3.05

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

y

1

4.01

Produces spines, thorns or burrs

n

4.02

Allelopathic

y

1

4.03

Parasitic

n

0

4.04

Unpalatable to grazing animals

y

1

4.05

Toxic to animals

n

-1

4.06

Host for recognized pests and pathogens

n

0

4.07

Causes allergies or is otherwise toxic to humans

n

0

4.08

Creates a fire hazard in natural ecosystems

y

1

4.09

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

n

0

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

y

1

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

n

-1

6.05

Requires specialist pollinators

n

-1

6.06

Reproduction by vegetative fragmentation

n

0

6.07

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

4

7.01

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

n

7.02

Propagules dispersed intentionally by people

y

1

7.03

Propagules likely to disperse as a produce contaminant

y

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

y

1

8.04

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

y

-1

8.05

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

Total score:

10

Supporting data:

Notes

Reference

1.01

No evidence.

1.02

1.03

2.01

"Native: AUSTRALASIA - Australia: Australia - New South Wales [e.], Tasmania, Victoria [most of range is not tropical]

http://www.ars-grin.gov/cgi-bin/npgs/html/tax_search.pl

2.02

(1)"naturalized in s. Europe, s. Africa, New Zealand, w. United States & Hawaii, & Macaronesia" (2)"E. globulus has naturalized all along the California coast as far north as Langlois, Oregon (just north of Port Orford). " [not tgropical]

(1)http://www.ars-grin.gov/cgi-bin/npgs/html/tax_search.pl (2)http://www.angelfire.com/bc/eucalyptus/globulus.html

2.03

(1)"Altitude range: 0 - 2400 m" (2)"Although bluegum eucalyptus has great climatic adaptability, the most successful introductions worldwide have been to locations with mild, temperate climates, or to high, cool elevations in tropical areas…"

(1)Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005. (2)http://www.na.fs.fed.us/pubs/silvics_manual/volume_2/eucalyptus/globulus.htm

2.04

(1)"naturalized in s. Europe, s. Africa, New Zealand, w. United States & Hawaii, & Macaronesia" (2)"E. globulus has naturalized all along the California coast as far north as Langlois, Oregon (just north of Port Orford). "

(1)http://www.ars-grin.gov/cgi-bin/npgs/html/tax_search.pl (2)http://www.angelfire.com/bc/eucalyptus/globulus.html

2.05

(1)"naturalized in s. Europe, s. Africa, New Zealand, w. United States & Hawaii, & Macaronesia" (2)"E. globulus has naturalized all along the California coast as far north as Langlois, Oregon (just north of Port Orford). "

(1)http://www.ars-grin.gov/cgi-bin/npgs/html/tax_search.pl (2)http://www.angelfire.com/bc/eucalyptus/globulus.html

3.01

(1)"naturalized in s. Europe, s. Africa, New Zealand, w. United States & Hawaii, & Macaronesia" (2)"E. globulus has naturalized all along the California coast as far north as Langlois, Oregon (just north of Port Orford). "

(1)http://www.ars-grin.gov/cgi-bin/npgs/html/tax_search.pl (2)http://www.angelfire.com/bc/eucalyptus/globulus.html

3.02

No evidence.

3.03

No evidence.

3.04

(1)"While E. globulus does not produce root suckers and does not naturally reproduce vegetatively, it still may have the potential to become a weed when seed escapes from plantations or amenity plantings. This has occurred in California, particularly around Los Angeles and San Francisco. The seed is not easily dispersed over large distances and the spread is likely to be relatively slow and hence should be easy to contain. Seed generally requires bare soil in order to germinate and the species is therefore not considered to be an aggressive colonizer." (2)"In California it is so well known that many regard it as a native Californian species. However, it has become so well established that it has spread into areas of natural vegetation and is listed among the exotic pest plants of greatest concern by the California Exotic Pest Plant Council." (3)"Blue gum aggressively invades neighboring plant communities from original plantings if adequate moisture is available for propagation by seed. Invasive in coastal locations, blue gum is rarely invasive in the Central Valley or in dry southern California locations. It is most invasive on sites subject to summer fog drip." (4)"Within groves, biological diversity is lost due to displacement of native plant communities and corresponding wildlife habitat. Abundance and diversity of understory vegetation is dependent on stand density. Understory establishment is inhibited by the production of allelopathic chemicals and by the physical barrier formed by high volumes of forest debris consisting of bark strips, limbs, and branches. "

(1)Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005. (2)http://farrer.csu.edu.au/ASGAP/e-glo.html (3)http://ucce.ucdavis.edu/datastore/detailreport.cfm?usernumber=48&surveynumber=182 (4)http://ucce.ucdavis.edu/datastore/detailreport.cfm?usernumber=48&surveynumber=182

3.05

Severa Eucalyptus species such as E. populnea,E. pilularis, E. ferruginear and E. cambageana are listed as principal weeds in Australia.

An electronic Atlas of Weeds and Invasive Species. CD ROM version 1. 1997. Based on the original work 'A Geographical Atlas of Weeds' by Holm et al.

4.01

No evidence

Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.

4.02

(1)"Like many eucalypts in plantations, E. globulus produces litter from leaves and bark which may restrict the germination of understorey species through the production of allelopathic chemicals (May and Ash, 1990). This may result in plantations on drier hillsides becoming a potential erosion risk because of poor development of the understorey and exposed soil surface. " (2)Allelopathic (3)"Abstract: The allelopathic potential of Eucalyptus globulus Labill. (gum tree) fresh and dried leaf leachates was studied using two perennial weeds, viz. purple nutsedge (Cyperus rotundus L.) and bermuda grass (Cynodon dactylon L. Pers) as test weeds. Aqueous leachate of fresh leaves of eucalyptus significantly suppressed the establishment of vegetative propagules and early seedling growth of the weeds. Leachate of fresh leaf cuttings had growth inhibitory effect on bermuda grass but showed growth promotion effect on purple nutsedge. Similarly the leachate of dried leaves of eucalyptus had differential influence on the growth of the two weeds. There is a possibility to harness the allelochemicals of eucalyptus leaves as herbicides for the management of these perennial weeds." (4)"Abstract: The effect of crude volatile oils from the leaves of Eucalyptus globulus and E. citriodora and the pure terpenes - cineole and limonene from these oils, (in vapour form) was studied on Phaseolus aurens, Lens esculentum, Hordeum vulgare and Avena sativa. The parameters like germination of seeds, seedling growth, values of cell survival, and content of water and chlorophyll of the crops formed the system of bioefficacy study. The allelopathic impact of the oil vapours from the eucalypt tree becomes evident from the negative response of the parameters studied. The impact of the E. citriodora oil vapours compared to that of E. globulus oil or the pure terpenes was seen to be relatively greater in almost all parameters under investigation. A strong reciprocal correlation that exist between the concentration and the seedling growth or the water content of the crops under study supports the dose linked allelopathic phenomenon. It is suggested that oil vapours of Eucalyptus exert their effect through impairing the respiratory as well as photosynthetic ability of the target plants."

(1)Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005. (2)http://plants.nrcs.usda.gov/cgi_bin/topics.cgi?earl=plant_attribute.cgi&symbol=EUGL (3)Babu, R. Chandra; Kandasamy, O. S. Allelopathic effect of Eucalyptus globulus Labill. on Cyperus rotundus L. and Cynodon dactylon L. Pers. Journal of Agronomy and Crop Science 179 (2) : 123-126 1997 (4)Kohli, R. K.; Singh, Daljit Allelopathic impact of volatile components from Eucalyptus on crop plants Biologia Plantarum (Prague) 33 (6) : 475-483 1991

4.03

No evidence

4.04

(1)Low palatability to browsing and grazing animals. (2)"Although bluegum eucalyptus is seldom browsed by cattle or sheep, seedlings are often severely girdled by rodents." "Bluegum eucalyptus has a considerable competitive advantage as compared with most other tree species in that its juvenile foliage is seldom browsed by cattle or sheep. This condition not only caused it to be a popular tree for planting in open grasslands years ago, but it permits natural seedlings to survive in the presence of grazing animals alongside the planted stands." (3)"PALATABILITY :
Bluegum eucalyptus foliage is unpalatable to cattle, sheep, and goats."

(1)http://plants.nrcs.usda.gov/cgi_bin/topics.cgi?earl=plant_attribute.cgi&symbol=EUGL (2)http://www.na.fs.fed.us/pubs/silvics_manual/volume_2/eucalyptus/globulus.htm (3)http://www.fs.fed.us/database/feis/plants/tree/eucglo/all.html

4.05

Toxicity - none

http://plants.nrcs.usda.gov/cgi_bin/topics.cgi?earl=plant_attribute.cgi&symbol=EUGL

4.06

Following is a list of pest species found to be associated with E. globulus: "Pest List
Botryotinia fuckeliana (grey mould-rot) fungus
Heteronychus arator (African black beetle) fungus African black beetle (a Scarabid).
Laetiporus sulphureus (brown checked wood rot) fungus
Mycosphaerella cruenta (leaf spot of cowpea) fungus Leaf-spot disease.
Mycosphaerella mori (leaf spot: mulberry) fungus Leaf-spot disease.
Pestalotiopsis funerea (leaf spot of mango) fungus
Phaeoseptoria eucalypti (leaf spot: Eucalyptus spp.) fungus
Phellinus torulosus fungus
Valsa sordida (valsa canker of poplar) fungus
Anoplognathus insect Christmas beetle.
Ctenarytaina eucalypti (blue gum psyllid) insect The Eucalyptus psyllid.
Eriococcus coriaceus insect Scale insects.
Glycaspis brimblecombei (red gum lerp psyllid) insect
Gonipterus gibberus (snout beetle, eucalyptus) insect The Eucalyptus Snout Beetle - a defoliator.
Gonipterus scutellatus (eucalyptus snout beetle) insect
Lipaphis insect Spring beetle.
Mnesampela privata insect Autumn gum moth.
Paropsis charybdis (eucalyptus tortoise beetle) insect
Phaulacridium vittatum (grasshopper, wingless) insect A wingless grasshopper.
Phoracantha recurva (eucalyptus longhorned borer) insect
Phoracantha semipunctata (eucalyptus longhorned borer) insect Stem borer - can be serious on drought-prone sites.
Phylacteophaga froggatti (leafblister sawfly) insect Leaf-blister sawfly.
Porotermes adamsoni (damp wood termite) insect
Spodoptera littoralis (cotton leafworm) insect
Xyleborus dispar (pear blight beetle) insect
Oligonychus coffeae (tea red spider mite) mite
[No evidence that the above are economic pests].

Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.

4.07

No evidence.

4.08

(1)"It may also present a fire risk when planted near urban areas due to the large amount of leaf and branch material which may be dropped over time by mature trees. Large branches may also present problems in urban areas as they tend to be shed in high winds. " (2)"The fuel complex formed by this debris is extremely flammable, and under severe weather conditions could produce drifting burning material with the potential to ignite numerous spot fires. Because stringy bark is carried away while burning, eucalyptus forests are considered the worst in the world for spreading spot fires. The Oakland hills firestorm was both intense and difficult to control because of the many stands of eucalyptus. Individual trees growing near structures or in public use areas are hazardous because of the potential for branch failure." (3)"In California, bluegum eucalyptus stands are highly susceptible to fire during the dry season. The bark, which hangs in strips from the stems, readily carries fire into the crowns, and the leaves contain volatile oils that produce a hot fire."

(1)Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005. (2)http://ucce.ucdavis.edu/datastore/detailreport.cfm?usernumber=48&surveynumber=182 (3)http://www.na.fs.fed.us/pubs/silvics_manual/volume_2/eucalyptus/globulus.htm

4.09

(1)"It cannot grow in the shade." (2)"Establishment of eucalyptus saplings within groves is inhibited by forest litter and duff, but can be significant following disturbances such as fire or harvesting operations " (3)"Blue gum is shade intolerant, and failure to regenerate within forests in the absence of fire is related to low light intensities." (4)Shade intolerant.

(1)http://www.pfaf.org/database/plants.php?Eucalyptus+globulus (2) and (3)http://ucce.ucdavis.edu/datastore/detailreport.cfm?usernumber=48&surveynumber=182 (4)http://plants.nrcs.usda.gov/cgi_bin/topics.cgi?earl=plant_attribute.cgi&symbol=EUGL

4.1

(1)"Soil types: acid soils; alluvial soils; calcareous soils; clay soils; lateritic soils; luvisols; sandstone soils; sandy soils; volcanic soils." (2)"The plant prefers light (sandy), medium (loamy) and heavy (clay) soils, requires well-drained soil and can grow in nutritionally poor soil. The plant prefers acid, neutral and basic (alkaline) soils." (3)"Blue gum grows well on a wide range of soils, but requires good drainage, low salinity, and a soil depth of two feet (0.6 m) or more." (4)"Bluegum eucalyptus grows well on a wide range of soils."

(1)Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005. (2)http://www.pfaf.org/database/plants.php?Eucalyptus+globulus (3)http://ucce.ucdavis.edu/datastore/detailreport.cfm?usernumber=48&surveynumber=182 (4)http://www.na.fs.fed.us/pubs/silvics_manual/volume_2/eucalyptus/globulus.htm

4.11

No evidence.

4.12

(1)"Blue gum typically grows in dense monospecific stands." (2)"The loss of biodiversity and habitat is a great threat from the Tasmanian Blue Gum tree, as it is from any eucalyptus. It creates virtual monocultures and can rapidly take over surrounding compatible areas, completely changing the ecosystem. That monoculture creates a loss of habitats for many species that relied on the previous system. Due to its great capacity for taking over a wide variety of habitats, the Blue Gum eucalyptus could possibly spread to a great range of systems where there is enough water content and create huge monocultures."

(1)http://ucce.ucdavis.edu/datastore/detailreport.cfm?usernumber=48&surveynumber=182 (2)http://www.columbia.edu/itc/cerc/danoff-burg/invasion_bio/inv_spp_summ/Eucalyptus_globulus.html

5.01

"Eucalyptus globulus varies from a multi-stemmed shrub on exposed sites to a very tall forest tree, 70-80 m tall, with a large open crown or a medium-sized woodland tree to 20 m."

Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.

5.02

5.03

5.04

6.01

Probably not - "In natural stands the flowering period is normally in spring and early summer during September-December."

Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.

6.02

(1)"Propagation is usually by seed which germinates readily in warm, moist conditions with no pre-treatment. The ideal temperature for the germination of E. globulus is 25°C with the first germinants appearing after about 5 days. There are approximately 70 000 viable seeds per kilogram." (2)"Propagation is from seed which germinates readily."

(1)Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005. (2)http://farrer.csu.edu.au/ASGAP/e-glo.html

6.03

(1)"Some interspecific breeding work has been carried out using E. globulus and this has primarily focused on E. nitens P E. globulus to improve E. globulus frost hardiness (Volker, 1995; Vergara and Griffin, 1997). Other hybrid combinations have been created but their performance has not been outstanding and their deployment has often been limited by poor rooting ability." (2)"The salt-waterlogging tolerance of Eucalyptus camaldulensis × E. globulus hybrids was compared with parental clones of E. camaldulensis, open-pollinated seedlings of E. globulus and E. camaldulensis x E. camaldulensis seedlings in a glasshouse trial. Seven-month-old plants were waterlogged for 10 weeks with a saline solution of increasing concentration to 350 mmol NaCl/L. Eucalyptus camaldulensis had higher tolerance to salt-waterlogging than E. globulus as assessed by survival and height growth rate. The performance of the hybrid families was intermediate between the 2 parental species as was the performance of progeny from crosses between salt tolerant E. camaldulensis parents. Within families some hybrid individuals performed as well as the E. camaldulensis parents. The most tolerant plants have been micropropagated for further experiments and field trials on saline agricultural land." (3)"Natural or controlled hybrids of bluegum eucalyptus with E. blakelyi, E. botryoides, E. cinerea, E. cypellocarpa, E. ovata, E. rudis, E. tereticornis, E. urnigera, and E. viminalis are known." (4)"The impact of inbreeding and hybridization on fitness was compared in the two co-occurring forest tree species, Eucalyptus ovata and E. globulus, aimed at explaining the rarity of their hybrids in nature. The success of selfing, open-pollination and outcrossing of both species and interspecific hybridization was monitored from seed-set to 10-year's growth in a field trial. There was a unilateral barrier to hybridization with seed-set obtained only with E. ovata females. The F1 hybrids exhibited reduced viability compared to intraspecific cross-types at virtually all stages of the life cycle and are clearly at a selective disadvantage compared with their open-pollinated E. ovata half-sibs with which they would directly compete in nature. Eucalyptus ovata and E. globulus overlap in their flowering time but the F1 hybrids flowered later with virtually no overlap with either species. The asynchronous flowering and reduced reproductive fitness of F1 hybrids would markedly limit the opportunity for advanced generation hybridization. Inbreeding similarly had a deleterious effect on the fitness of both species, and the F1 hybrids were most competitive with the E. ovata selfs. It is argued that changes in inbreeding levels of parental populations may be a key factor affecting the relative fitness of hybrids and their potential to impact on the pure species gene pool. Reduced fitness of the pure species through inbreeding may result in hybridization having its greatest evolutionary impact in small founder or relict populations." [Natural hybrids rare but possible]. (5)The interspecific natural hybrids with E. grandis are characterized by hybrid inviability and hybrid abnormality.

(1)Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005. (2)http://cat.inist.fr/?aModele=afficheN&cpsidt=1129436 (3)http://www.na.fs.fed.us/pubs/silvics_manual/volume_2/eucalyptus/globulus.htm (4)http://www.nature.com/hdy/journal/v85/n3/full/6887390a.html (4)http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=
Retrieve&db=PubMed&list_uids=12838392&dopt=Abstract

6.04

Probably not - (1)"As in almost all eucalyptus, pollen is usually viable before the stigma becomes receptive." (2)"Like most eucalypts, E. globulus (sub sp globulus) has a mixed mating system, is pollinated by a variety of insect and bird taxa (Hingston & Potts, 1998) and exhibits extreme inbreeding depression following selfing." "Self-pollination significantly reduced seed-set in both species (E. globulus P < 0.01, E. ovata P < 0.001), and no significant difference was found between assisted and unassisted self-pollination means (1.2-1.1 for E. globulus and 0.1-0.1 for E. ovata, respectively).

(1)http://www.na.fs.fed.us/pubs/silvics_manual/volume_2/eucalyptus/globulus.htm (2)http://www.nature.com/hdy/journal/v85/n3/full/6887390a.html

6.05

(1)"The flowers are predominantly insect pollinated although birds and small mammals may also assist in pollination." (2)"The flowers are hermaphrodite (has both male and female organs) and are pollinated by Bees." (3)"The yellowish white flowers are pollinated by insects, hummingbirds, and other pollen and nectar feeders. "

(1)Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005. (2)http://www.pfaf.org/database/plants.php?Eucalyptus+globulus (3)http://www.na.fs.fed.us/pubs/silvics_manual/volume_2/eucalyptus/globulus.htm

6.06

(1)"While E. globulus does not produce root suckers and does not naturally reproduce vegetatively …" (2)Vegetative spread rate - none.

(1)Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005. (2)http://plants.nrcs.usda.gov/cgi_bin/topics.cgi?earl=plant_attribute.cgi&symbol=EUGL

6.07

(1)"Eucalyptus globulus is considered a fast growing species and height growth of 2-3 m per year is commonly achieved on favourable sites." "Mature capsules are present during autumn and winter and may persist for more than a year." "Trees in irrigated and fertilized plantations can flower as early as 4 years of age while slower growing trees may take up to 10 years to flower. In managed seed orchards, some individual trees can flower at a relatively young age but it may take some years before sufficient widespread flowering occurs in the orchard to ensure adequate cross pollination." (2)"Seed set begins at approximately four to five years of age. Good seed crops are produced in most locations at three- to five-year intervals. "

(1)Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005. (2)http://ucce.ucdavis.edu/datastore/detailreport.cfm?usernumber=48&surveynumber=182

7.01

Probably not - no evidence that the speceis is grown in heavily trafficked areas.

7.02

Probably yes -(1) "The wood is strong and moderately durable and is used for light and heavy construction and regarded as being excellent for cellulose and paper manufacture." (2)An ornamental tree. (3)"The trees have great ornamental purposes and have been used in everything from home gardens, recreation parks, and parts of living art work such as in the Trees exhibit at the University of California, San Diego. The oils from the leaves and shoots are used in a variety of fragrant products such as aromatherapy soaps, candles, oils, etc. It has also been used medicinally for its antiseptic and antibacterial components in a large variety of traditional and over-the-counter medicines. The leaves and oil can be used as an insect repellant."

(1)Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005. (2)http://ucce.ucdavis.edu/datastore/detailreport.cfm?usernumber=48&surveynumber=182 (3)http://www.columbia.edu/itc/cerc/danoff-burg/invasion_bio/inv_spp_summ/Eucalyptus_globulus.html

7.03

"Weed: also potential seed contaminant."

http://www.ars-grin.gov/cgi-bin/npgs/html/tax_search.pl

7.04

(1)"Seeds are small and abundant. Capsules open immediately on ripening, and seed is dispersed by wind within one to two months. Dispersal distance from one 131-foot (40 m) tall tree, with winds of six miles per hour (10 km/h), was sixty-six feet (20 m). " (2)"The seed is not easily dispersed over large distances and the spread is likely to be relatively slow and hence should be easy to contain." (3)"Capsules release seed immediately on ripening and the seed is dispersed by wind."

(1)Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005. (3)http://www.na.fs.fed.us/pubs/silvics_manual/volume_2/eucalyptus/globulus.htm

7.05

No evidence

7.06

No evidence

7.07

No evidence that the seeds have any means of attachment.

7.08

No evidence

8.01

(1)"The fruits are woody and range from 1.5 to 2.5 cm in diameter. Numerous small seeds are shed through valves which open on the top of the fruit." (2)"Capsules single at leaf base, broadly top-shaped or rounded, 1–1.5 cm long, 2–2.5 cm wide, 4-angled, warty. Seeds many, irregularly elliptical, 2–3 mm long, dull black." [tiny pepper-like seeds, hundreds per capsule].

(1)http://en.wikipedia.org/wiki/Tasmanian_Blue_Gum (2)http://www.hort.purdue.edu/newcrop/duke_energy/Eucalyptus_globulus.html

8.02

(1)"Studies undertaken at the Australian Tree Seed Centre, CSIRO Forestry and Forest Products, have established that E. globulus can be successfully stored for several years at room temperature as long as humidity remains low, so that the moisture content of the seed remains in the range of 6 - 10%. " (2)"No seed treatment is required. Fresh seeds germinate well but deteriorate rapidly." (3)"The seed has a long viability." [But no evidence on how long the seeds are vialble]. (4)"Seed stored in the soil under older stands often germinates prolifically following logging and the resultant natural reproduction interferes with the management of the coppice stand." (4)"Abstract: The hypothesis that tree plantations may foster the regeneration of native woody species, was tested through studies of understory floristic composition, height-class distribution of naturally regenerated seedlings and saplings of indigenous woody species, and soil seed banks in the native and exotic tree plantations in Central Ethiopia. A total of 70 plots, having 10X10 m area each, were studied in six monoculture plantation stands of four exotic species, i.e. Cupressus lusitanica (2 stands of different age), Eucalyptus globulus, Pinus patula, P. radiata and Juniperus procera, an indigenous coniferous species. Ages of the plantations ranged between 14 and 42 years. Soil seed bank analysis was also undertaken from soil samples collected in each of the 70 plots to examine the similarity between the soil seed flora and aboveground vegetation. Vegetation diversity was assessed through analyses of floristic composition, species richness and abundance. A total of 37 naturally regenerated indigenous woody species were recorded beneath all plantation stands, with densities ranging between 1630 and 18270 individuals ha-1. There was considerable variation among plantation stands/species with respect to the density of naturally regenerated native woody species. Generally, seedling populations were the most abundant components of the regeneration in most of the plantation stands, forming 85% of the total regeneration count. A total of 68 plant species represented by 53 herbs, eight woody species and seven grasses were recorded in the soil seed bank from all stands. Similarity between the soil seed banks and aboveground flora (both seedlings and larger plants) was very low implying that the role of soil seed banks in the regeneration is low and dispersal of seeds from the adjacent natural forest plays an important role in the process. These results support the concept that forest plantations can foster the regeneration of native woody species and increase biodiversity in the plantation stands, if seed sources are available in the vicinity of the plantations." [No evidence on the longevity of the seeds in the seed bank - probably not longer than a year as the seeds are relatively small].

(1)Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005. (2)http://www.hort.purdue.edu/newcrop/duke_energy/Eucalyptus_globulus.html (3)http://www.pfaf.org/database/plants.php?Eucalyptus+globulus (4)http://www.na.fs.fed.us/pubs/silvics_manual/volume_2/eucalyptus/globulus.htm

8.03

(1)"The most successful control method is to make grooves in the tree bases and flood them with a 3lb/gal solution of glyphosphate in water, killing the tree permanently."
(2)"The most effective control of sprouting is achieved through application of triclopyr or glyphosate directly to the outer portion of the stump’s cut surface at the time of tree felling. Triclopyr (as Garlon 4® and Garlon 3A®) should be applied at the rate of 80 percent in an oil carrier. Imazapyr (as Arsenal or Stalker) can be used as an alternate to Garlon. Glyphosate (as Roundup® or Rodeo®) should be applied at 100 percent. Stumps should be cut as low to the ground as practical and brushed clean of sawdust to maximize absorption of the herbicide. For best results, herbicides should be applied to the freshly cut surface as soon after cutting as possible. Maximum success is achieved if cutting occurs in fall (Carrithers, pers. comm.). Complete control of sprouting on every stump will not always be achieved. Any resprouts, when three to five feet tall, should be treated with a foliar application of 2 percent of triclopyr or glyphosate. ..."

(1)http://www.columbia.edu/itc/cerc/danoff-burg/invasion_bio/inv_spp_summ/Eucalyptus_globulus.html (2)http://ucce.ucdavis.edu/datastore/detailreport.cfm?usernumber=48&surveynumber=182

8.04

(1)"Blue gum sprouts readily from the main trunk, from stumps of all sizes and ages, from the lignotuber, and from roots. Large masses of foliage are produced by sprouting stumps after tree felling. Numerous clusters of shoots later thin to one stem per cluster. A number of small-diameter stems can continue to thrive on each stump, resulting in bush-like growth." (2)Ability to resprout (3)"Trees are rarely killed by fire, however, as they sprout vigorously from the stems and bases."

(1)http://ucce.ucdavis.edu/datastore/detailreport.cfm?usernumber=48&surveynumber=182 (2)http://plants.nrcs.usda.gov/cgi_bin/topics.cgi?earl=plant_attribute.cgi&symbol=EUGL (3)http://www.na.fs.fed.us/pubs/silvics_manual/volume_2/eucalyptus/globulus.htm

8.05

Don’t know.


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