Pacific Island Ecosystems at Risk (PIER)


Koelreuteria elegans


RISK ASSESSMENT RESULTS: High risk, score: 8


Revised 28 April 2009

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

Koelreuteria elegans ssp. formosana (Hayata) F.G. Mey. Family - Sapindaceae. Common Names(s) - Golden rain tree, Flamegold tree. Synonym(s) - Koelreuteria formosana Hayata, Koelreuteria vitiensis A.C. Sm.

Answer

Score

1.01

Is the species highly domesticated?

y=-3, n=0

n

0

1.02

Has the species become naturalized where grown?

y=1, n=-1

1.03

Does the species have weedy races?

y=-1, n=-1

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

2

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, n=0

y

1

2.04

Native or naturalized in regions with tropical or subtropical climates

y=1, n=0

y

1

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

2

3.02

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

n=0

y

2

3.03

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

n=0

n

0

3.04

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

n=0

y

4

3.05

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

n=0

n

0

4.01

Produces spines, thorns or burrs

y=1, n=0

n

0

4.02

Allelopathic

y=1, n=0

n

0

4.03

Parasitic

y=1, n=0

n

0

4.04

Unpalatable to grazing animals

y=1, n=-1

4.05

Toxic to animals

y=1, n=0

n

0

4.06

Host for recognized pests and pathogens

y=1, n=0

n

0

4.07

Causes allergies or is otherwise toxic to humans

y=1, n=0

n

0

4.08

Creates a fire hazard in natural ecosystems

y=1, n=0

n

0

4.09

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

y=1, n=0

n

0

4.10

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

y=1, n=0

y

1

4.11

Climbing or smothering growth habit

y=1, n=0

n

0

4.12

Forms dense thickets

y=1, n=0

5.01

Aquatic

y=5, n=0

n

0

5.02

Grass

y=1, n=0

n

0

5.03

Nitrogen fixing woody plant

y=1, n=0

n

0

5.04

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

y=1, n=0

n

0

6.01

Evidence of substantial reproductive failure in native habitat

y=1, n=0

n

0

6.02

Produces viable seed.

y=1, n=-1

y

1

6.03

Hybridizes naturally

y=1, n=-1

6.04

Self-compatible or apomictic

y=1, n=-1

6.05

Requires specialist pollinators

y=-1, n=0

6.06

Reproduction by vegetative fragmentation

y=1, n=-1

n

-1

6.07

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

See left

3

0

7.01

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

y=1, n=-1

y

1

7.02

Propagules dispersed intentionally by people

y=1, n=-1

y

1

7.03

Propagules likely to disperse as a produce contaminant

y=1, n=-1

n

-1

7.04

Propagules adapted to wind dispersal

y=1, n=-1

y

1

7.05

Propagules water dispersed

y=1, n=-1

7.06

Propagules bird dispersed

y=1, n=-1

n

-1

7.07

Propagules dispersed by other animals (externally)

y=1, n=-1

n

-1

7.08

Propagules survive passage through the gut

y=1, n=-1

n

-1

8.01

Prolific seed production (>1000/m2)

y=1, n=-1

n

-1

8.02

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

y=1, n=-1

8.03

Well controlled by herbicides

y=-1, n=1

y

-1

8.04

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

y=1, n=-1

8.05

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

y=-1, n=1

Total score:

8

Supporting data:

Notes

Source

1.01

(1)No evidence

(1)Staples, G.W. and D.R. Herbst. 2005. A Tropical Garden Flora: Plants Cultivated in the Hawaiian Islands and Other Tropical Places. Bishop Museum Press. Honolulu, HI.

1.02

1.03

2.01

(1)found naturally in Taiwan and Fiji…The subspecies endemic to Taiwan was introduced to the U.S. in 1915 and must have reached Hawaii soon thereafter.

(1)Staples, G.W. and D.R. Herbst. 2005. A Tropical Garden Flora: Plants Cultivated in the Hawaiian Islands and Other Tropical Places. Bishop Museum Press. Honolulu, HI.

2.02

2.03

(1)Hardiness Range 9A to 11; In most years, trees usually survive the cold temperatures in hardiness zone 8B. (2)Very tough, drought-tolerant (3)Can tolerate frost, "these trees come from the mountains of Taiwan" [high elevations while also invasive at low elevations in Florida]

(1)Horticopia A-Z.Horticopia, Inc., Purcellville, VA. ISBN 1-887215-07-7. (2)http://www.redwoodbarn.com/trees.html (3)http://www.treedavis.org/w97.html

2.04

(1)found naturally in Taiwan and Fiji…The subspecies endemic to Taiwan was introduced to the U.S. in 1915 and must have reached Hawaii soon thereafter…It has escaped cultivation in southern Florida and become sparingly naturalized.

(1)Staples, G.W. and D.R. Herbst. 2005. A Tropical Garden Flora: Plants Cultivated in the Hawaiian Islands and Other Tropical Places. Bishop Museum Press. Honolulu, HI.

2.05

(1)Golden rain tree is occasionally grown as a street or ornamental tree here, as it is in California and the mainland Gulf Coast states. (2) Florida, Louisiana, Mississippi, Texas, (3) Hawaii, (4) Argentina

(1)Staples, G.W. and D.R. Herbst. 2005. A Tropical Garden Flora: Plants Cultivated in the Hawaiian Islands and Other Tropical Places. Bishop Museum Press. Honolulu, HI. (2)USDA, NRCS. 2002. The PLANTS Database, Version 3.5 (http://plants.usda.gov). National Plant Data Center, Baton Rouge, LA 70874-4490 USA.
(3)Neal, M.C. 1965. In Gardens of Hawaii. Bernice p. Bishop Museum Special Publication 50. Bishop Museum Press, Honolulu.
(4)Ferrucci, M. S.; Pompert, M. de .1996. New location for cultivated Sapindaceae: Koelreuteria elegans subsp. formosana. (Foreign Title: Nueva cita de Sapindaceae cultivada: Koelreuteria elegans subsp. formosana.) Bonplandia, 1996, Vol. 9, No. 1/2, pp. 25-27, 9 ref.

3.01

(1)It has escaped cultivation in southern Florida and become sparingly naturalized. (2)"Trees have escaped cultivation and can be seen in many areas invading roadside woodlands." Attributes and Features- Naturalizing- Invasive plant (3)To date, K. elegans ssp. formosana has only naturalised in Brisbane and near Noosa in Queensland and near Lismore in New South Wales. Naturalised specimens were first recorded from both states in 2001, growing amongst other weeds and native species in urban bushland, gullies, parks, undeveloped land and streets. The potential distribution of K. elegans ssp. formosana includes Western Australia and the Northern Territory.

(1)Staples, G.W. and D.R. Herbst. 2005. A Tropical Garden Flora: Plants Cultivated in the Hawaiian Islands and Other Tropical Places. Bishop Museum Press. Honolulu, HI. (2)Horticopia A-Z.Horticopia, Inc., Purcellville, VA. ISBN 1-887215-07-7. (3)http://www.weedscrc.org.au/documents/wmg_chinese_rain_tree.pdf [Accessed 21 Jan 2009] (4)Starr, F., K. Starr and L.L. Loope. 2008. New plant records from the Hawaiian Archipelago. Pp. 44-49 in N. L. Evenhuis and L.C. Eldredge (eds.). Records of the Hawaii Biological Survey for 2007. Bishop Museum Occasional Papers 100: 1-55.

3.02

(1)"Seedlings germinate everywhere around this tree creating quite a weed problem - a nightmare actually." (2)A VERY weedy tree. Seedling come up in the landscape by the thousands, requiring constant removal from areas where it is not desired. Not recommended for general use if not ready to pull up seedlings. [landscape/amenity weed]

(1)Horticopia A-Z.Horticopia, Inc., Purcellville, VA. ISBN 1-887215-07-7. (2)http://sarasota.extension.ufl.edu/Hort/MG/Golden_Raintree.htm

3.03

(1)No evidence

 

3.04

(1) "Trees have escaped cultivation and can be seen in many areas invading roadside woodlands. In most years, trees usually survive the cold temperatures in hardiness zone 8B."
(2) "Listed by the Brisbane City Council as a weed of bushland around Brisbane (Csurhes & Edwards, 1998). In Florida it has escaped from cultivation in certain areas (Meyer, 1976)."
(3) on "The Alert List for Environmental Weeds" (4)Florida - Category II - Invasive exotics that have increased in abundance or frequency but have not yet altered Florida plant communities to the extent shown by Category I species. [evidence of environmental problems in multiple geographic locations] (5)K. elegans ssp. formosana is a problem weed in Japan and the USA, where it has naturalised across five states. The decision to place K. elegans ssp. formosana on the Australian Alert List was based on this invasive behaviour...Because K. elegans ssp. formosana spreads so quickly and poses such a serious threat, its control should be undertaken with the appropriate expertise and adequate resources.

(1) Horticopia A-Z.Horticopia, Inc., Purcellville, VA. ISBN 1-887215-07-7.
(2) http://www.hear.org/pier/species/koelreuteri_elegans.htm
(3) http://www.weeds.crc.org.au/documents/weed_watch_vol2_no4.pdf (4)http://www.fleppc.org/ (5)http://www.weedscrc.org.au/documents/wmg_chinese_rain_tree.pdf [Accessed 21 Jan 2009]

3.05

(1)"Golden rain tree (K. paniculata) should not be planted in Florida (or in similar climates) because it becomes invasive and displaces native plants. The Florida Exotic Pest Plant Council lists golden rain tree as an invader with the potential to disrupt native plant communities." [this information is not accurate - fleppc only lists K. elegans] (2)Koelreuteria bipinnata is capable of self-pollination and subsequent self-fertilization, and a single plant can give rise to an entire population. This species has been observed invading into and establishing in open and wooded areas, and probably has the potential to become invasive.

(1)http://www.floridata.com/ref/K/koel_p.cfm (2)http://www.hsu.edu/default.aspx?id=6384 [Accessed 21 Jan 2009]

4.01

(1)No evidence

(1)Staples, G.W. and D.R. Herbst. 2005. A Tropical Garden Flora: Plants Cultivated in the Hawaiian Islands and Other Tropical Places. Bishop Museum Press. Honolulu, HI.

4.02

(1)no evidence

(1)http://www.weedscrc.org.au/documents/wmg_chinese_rain_tree.pdf [Accessed 21 Jan 2009]

4.03

(1)No evidence

(1)Staples, G.W. and D.R. Herbst. 2005. A Tropical Garden Flora: Plants Cultivated in the Hawaiian Islands and Other Tropical Places. Bishop Museum Press. Honolulu, HI.

4.04

(1)Unknown [Sapindaceae with saponins?]

(1)http://216.239.57.104/search?q=cache:ws6pAbBSyXMJ:www.hnd.usace.army.mil/techinfo/CPW/PWTB200-1-19/.%255CPWTB%2520200-1-19_AppendixB.pdf+Koelreuteria+elegans+cattle&hl=en&ie=UTF-8

4.05

(1)no evidence

(1)http://www.weedscrc.org.au/documents/wmg_chinese_rain_tree.pdf [Accessed 21 Jan 2009]

4.06

(1) Pests: Usually none but scales can cause some problems. Diseases: Root rot occurs on old trees. A canker causes dead and sunken areas on the bark. Verticillium wilt can cause decline. [all above pests are generalists]
(2) Jadera haematoloma (no economic importance)
(3) fungi recorded
Armillariella tabescens: FL (generalist)
Bulbouncinula bulbosa: Taiwan (no economic importance)
Cercospora sp.: FL
Corynespora sp.: FL
Fusarium solani: FL (generalist)
Macrophomina phaseolina: FL (generalist)
Phyllosticta sp.: FL
Pythium sp.: FL
Rhizoctonia sp.: FL Rhizoctonia sp.: FL

(1) Horticopia A-Z.Horticopia, Inc., Purcellville, VA. ISBN 1-887215-07-7.
(2) Carroll, S. P.; Klassen, S. P.; Dingle, H. (1998) Rapidly evolving adaptations to host ecology and nutrition in the soapberry bug. Evolutionary Ecology, 1998, Vol. 12, No. 8, pp. 955-968, 31 ref.
(3) http://nt.ars-grin.gov/fungaldatabases/all/FindRecOneFungusFrame.cfm

4.07

(1)Koelreuteria (vomiting, abdominal pain, and in some cases diarrhea) [no evidence that it is consumed]

(1)http://www.minitaly.com/floppy/txt/Plants_and_Cats.htm#Koelreuteria

4.08

(1)Low flammability

(1)Horticopia A-Z.Horticopia, Inc., Purcellville, VA. ISBN 1-887215-07-7.

4.09

(1)Exposure Full sun (2)Flamegold is a tough tree which should be grown in full sun on any well-drained soil, in sand or heavy clay, and should receive moderate watering. The tree becomes leggy and thin in partial shade.

(1)Horticopia A-Z.Horticopia, Inc., Purcellville, VA. ISBN 1-887215-07-7. (2)http://hort.ufl.edu/trees/KOEELEA.pdf [Accessed 21 Jan 2009]

4.10

(1)"Flamegold is a tough tree which should be grown in full sun on any well-drained soil, in sand, loam or heavy clay, and should receive moderate watering. "; "Soil Condition Loamy, sandy, clay, acidic, neutral, alkaline, tolerates salt, drought tolerant, flood tolerant" (2)It grows on a wide range of soil types and may be tolerant of light salt spray, but not of saline conditions.

(1)Horticopia A-Z.Horticopia, Inc., Purcellville, VA. ISBN 1-887215-07-7. (2)http://www.weedscrc.org.au/documents/wmg_chinese_rain_tree.pdf [Accessed 21 Jan 2009]

4.11

(1)tree

(1)Neal, M.C. (1965) In Gardens of Hawaii. Bernice p. Bishop Museum Special Publication 50. Bishop Museum Press, Honolulu. 924pp. p. 536

4.12

(1)"Seedlings germinate everywhere around this tree creating quite a weed problem - a nightmare actually." (2)A VERY weedy tree. Seedling come up in the landscape by the thousands, requiring constant removal from areas where it is not desired.

(1)Horticopia A-Z.Horticopia, Inc., Purcellville, VA. ISBN 1-887215-07-7. (2)http://sarasota.extension.ufl.edu/Hort/MG/Golden_Raintree.htm

5.01

(1)Terrestrial

(1)Staples, G.W. and D.R. Herbst. 2005. A Tropical Garden Flora: Plants Cultivated in the Hawaiian Islands and Other Tropical Places. Bishop Museum Press. Honolulu, HI.

5.02

(1)Sapindaceae

(1)Staples, G.W. and D.R. Herbst. 2005. A Tropical Garden Flora: Plants Cultivated in the Hawaiian Islands and Other Tropical Places. Bishop Museum Press. Honolulu, HI.

5.03

(1)Sapindaceae

(1)Staples, G.W. and D.R. Herbst. 2005. A Tropical Garden Flora: Plants Cultivated in the Hawaiian Islands and Other Tropical Places. Bishop Museum Press. Honolulu, HI.

5.04

(1)Monoecious tree

(1)Staples, G.W. and D.R. Herbst. 2005. A Tropical Garden Flora: Plants Cultivated in the Hawaiian Islands and Other Tropical Places. Bishop Museum Press. Honolulu, HI. (2)Yang, JengChuann; Chen, YuHsin; Lin, TsanPiao (2000) Seed storage behavior of Gordonia axillaris (Boxb.) Dietr., Pistacia chinensis Bunge, and Koelreuteria henryi Dummer. Taiwan Journal of Forest Science, 2000, Vol. 15, No. 1, pp. 91-104, 20 ref.

6.01

(1)No evidence

(1)http://www.foc.org/china/mss/volume12/Sapindaceae.pdf [Accessed 21 Jan 2009]

6.02

(1)Propagation is from seed. (2)" non-dormant viable seeds of these 3 species would germinate completely within 8 weeks in germination tests. "

(1)Staples, G.W. and D.R. Herbst. 2005. A Tropical Garden Flora: Plants Cultivated in the Hawaiian Islands and Other Tropical Places. Bishop Museum Press. Honolulu, HI.

6.03

Unknown

6.04

(1)Koelreuteria bipinnata is capable of self-pollination and subsequent self-fertilization, and a single plant can give rise to an entire population [related species self-compatible]

(1)http://www.hsu.edu/default.aspx?id=6384 [Accessed 21 Jan 2009]

6.05

(1)small yellow flowers, but morphology and position of stigma appears to be specialized (2)Flowers yellow, ca. 5 mm in diam. Sepals 5, oval or ovate-triangular, ciliate. Petals 5, lanceolate or oblong, with 2-lobed, tuberculate toothed scale, claw hairy. Stamens 7 or 8; filaments hairy. [floral structure suggest wind or insect pollination]

(1)http://www.cuyamaca.net/oh170/Plant_TNails_2/Koelrueteria_bipinatta_-_Flower_copy.JPG (2)http://www.foc.org/china/mss/volume12/Sapindaceae.pdf [Accessed 21 Jan 2009]

6.06

(1)no evidence

(1)Staples, G.W. and D.R. Herbst. 2005. A Tropical Garden Flora: Plants Cultivated in the Hawaiian Islands and Other Tropical Places. Bishop Museum Press. Honolulu, HI.

6.07

(1)GROWTH RATE: Fast. SIZE: Typically 35-40 feet tall [minimum for a fast growing medium tree]

(1)http://sarasota.extension.ufl.edu/Hort/MG/Golden_Raintree.htm

7.01

(1)"Seedlings germinate everywhere around this tree creating quite a weed problem - a nightmare actually. Trees have escaped cultivation and can be seen in many areas invading roadside woodlands." [wind dispersed fruits can easily be spread along roadsides by vehicles]

(1)Horticopia A-Z.Horticopia, Inc., Purcellville, VA. ISBN 1-887215-07-7.

7.02

(1)Golden rain tree is occasionally grown as a street or ornamental tree here, as it is in California and the mainland Gulf Coast states.

(1)Staples, G.W. and D.R. Herbst. 2005. A Tropical Garden Flora: Plants Cultivated in the Hawaiian Islands and Other Tropical Places. Bishop Museum Press. Honolulu, HI.

7.03

(1)no evidence

(1)http://www.weedscrc.org.au/documents/wmg_chinese_rain_tree.pdf [Accessed 21 Jan 2009]

7.04

(1)Fruit ellipsoid, 3-angled, ca 1.5" long, pinkish to rose, inflated and papery. (2)Table 2. "wind dispersal syndrome"

(1)Staples, G.W. and D.R. Herbst. 2005. A Tropical Garden Flora: Plants Cultivated in the Hawaiian Islands and Other Tropical Places. Bishop Museum Press. Honolulu, HI. (2)http://hbs.bishopmuseum.org/pdf/op65.pdf

7.05

(1)It is not known exactly how the seeds are dispersed, but it is possible that water may contribute, as supported by evidence of infestation of gullies in Brisbane. [papery seed capsules may float] (2)Water may contribute to the spread of the seeds, although this has not yet been proven.

(1)http://www.weedscrc.org.au/documents/wmg_chinese_rain_tree.pdf [Accessed 21 Jan 2009] (2)http://plants.ifas.ufl.edu/parks/golden_rain_tree.html [Accessed 21 Jan 2009]

7.06

(1)Fruit ellipsoid, 3-angled, ca 1.5" long, pinkish to rose, inflated and papery. (2)Table 2. "wind dispersal syndrome"

(1)Staples, G.W. and D.R. Herbst. 2005. A Tropical Garden Flora: Plants Cultivated in the Hawaiian Islands and Other Tropical Places. Bishop Museum Press. Honolulu, HI. (2)http://hbs.bishopmuseum.org/pdf/op65.pdf

7.07

(1)No means of external attachment

(1)Staples, G.W. and D.R. Herbst. 2005. A Tropical Garden Flora: Plants Cultivated in the Hawaiian Islands and Other Tropical Places. Bishop Museum Press. Honolulu, HI.

7.08

(1)Fruit ellipsoid, 3-angled, ca 1.5" long, pinkish to rose, inflated and papery. [no evidence of ingestion of these wind-adapted capsules] (2)Table 2. "wind dispersal syndrome"

(1)Staples, G.W. and D.R. Herbst. 2005. A Tropical Garden Flora: Plants Cultivated in the Hawaiian Islands and Other Tropical Places. Bishop Museum Press. Honolulu, HI. (2)http://hbs.bishopmuseum.org/pdf/op65.pdf

8.01

(1)" Capsules ellipsoidal, the valves rotund to suborbicular (placenta continuous and nonwinged), 3.4-5 (-6) cm long, (2.5-) 3.1-4.6 cm wide, inner side lustrous, reticulate-veined, scattered-pubescent when young, becoming glabrous, deep rose-purple while young, brownish at maturity; styles (1.5-) 2-6 mm long, seeds pyriform to nearly spherical, 5.2-5.5 mm in diameter, black, slightly rugose or smooth.” (Meyer, 1976)" [probably not, relatively large seed] (2)based on photo, two seed per fruit and roughly 100-200 seeds per panicle with roughly 1 panicle per square meter

(1)http://www.hear.org/pier/species/koelreuteri_%20elegans.htm (2)http://aoki2.si.gunma-u.ac.jp/BotanicalGarden/PICTs/taiwan-mokugenji.jpeg

8.02

(1)The effects of moisture content and temperature on the storage behaviour of seeds of Gordonia axillaris, Pistacia chinensis, and Koelreuteria henryi [Koelreuteria elegans var. formosana] were investigated. The germination percentages of these 3 species did not decline after 18-24 months of storage at -20 deg C, 5% moisture content, therefore, confirming their orthodox seed storage behaviour. The optimum seed moisture contents for the storage of seeds of these 3 species at -20 deg C were 5-10%, 4-9%, and 5-10% (fresh weight), respectively. Only seeds of P. chinensis showed slight dormancy; non-dormant viable seeds of these 3 species would germinate completely within 8 weeks in germination tests. After prechilling at 4 deg C for 2 months, the germination percentage of fresh mature seeds of P. chinensis increased but not in the other 2 species. The mean germination times of seeds of G. axillaris and P. chinensis were reduced by 50%by prechilling 8 and 2 months at 4 deg C, respectively. The effect of prechilling treatment on the mean germination time of seeds of K. henryi was not apparent.
[seed storage orthodox, but no evidence of dormancy] (2)Propagation is by seed, which will germinate within six to eight days. (3)Although it is not known exactly how long K. elegans ssp. formosana seeds can survive in the soil (the soil ‘seedbank’), experiments have shown that the seeds can achieve a 90–100% success rate of germination after 10 months of moist storage at 4 degrees C. This suggests that the seedbank may be viable for some time.

(1)Yang, JengChuann; Chen, YuHsin; Lin, TsanPiao (2000) Seed storage behavior of Gordonia axillaris (Boxb.) Dietr., Pistacia chinensis Bunge, and Koelreuteria henryi Dummer. Taiwan Journal of Forest Science, 2000, Vol. 15, No. 1, pp. 91-104, 20 ref. (2)http://edis.ifas.ufl.edu/ST337 (3)http://www.weedscrc.org.au/documents/wmg_chinese_rain_tree.pdf [Accessed 21 Jan 2009]

8.03

(1)Table of Current Control Methods for Priority Environmental Weeds: Stem inject with equal parts solution of Glyphosate 360® and water. Other control methods include: Cut stump with equal parts solution of Glyphosate 360® and water. Dig up/hand pull young plants. [herbicide is the major method used to control the species] (2)Cut stump treatments with 100% triclopyr-amine are effective but should be applied to the outer lay of bark within 1 minute of cutting.

(1)http://www.nrm.qld.gov.au/pests/environmental_weeds/pdf/controltable.pdf (2)http://plants.ifas.ufl.edu/parks/golden_rain_tree.html [Accessed 21 Jan 2009]

8.04

(1) "Root system is a bit coarse resulting in poor root balls in many soils. Regular root pruning during production may enhance the quality of the root ball. Many trees are offered in containers. Those designed to minimize circling roots would be suggested. Be sure to clear all turf away from beneath the branches and mulch to the dripline, especially on young trees, to reduce competition with turf and weeds. This will allow roots to become well established and keep plants healthier." [relatively inactive root system]

(1) Horticopia A-Z.Horticopia, Inc., Purcellville, VA. ISBN 1-887215-07-7.

8.05

Unknown


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