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

Juniperus chinensis; Chinese juniper

Answer

1.01

Is the species highly domesticated?

y=-3, n=0

n

1.02

Has the species become naturalized where grown?

y=-1, n=-1

n

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

0

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

y

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

n

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

n

3.05

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

n=0

y

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

y

4.05

Toxic to animals

y=1, n=0

n

4.06

Host for recognized pests and pathogens

y=1, n=0

y

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

4.09

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

y=1, n=0

n

4.1

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

y=1, n=0

n

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

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

n

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

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

7.07

Propagules dispersed by other animals (externally)

y=1, n=-1

7.08

Propagules survive passage through the gut

y=1, n=-1

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

n

8.04

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

y=1, n=-1

n

8.05

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

y=-1, n=1

Total score:

-3

Source

Notes

1.01

Dehgan, B. (1998) Landscape Plants for Subtropical Climates. University Press of Florida., Gainesville, FL. 638pp. P.28

"many varieties and cultivars"

1.02

no evidence

1.03

no evidence

2.01

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

Natural latitude range
Approximate limits north to south: 40°N to 25°N
List of countries with natural populations
Asia
[China] Anhui, Fujian, Gansu, Guizhou, Hebei, Henan, Hubei, Hunan, Jiangxi, Nei Menggu, Shaanxi, Shanxi, Xizhang, Yunnan
Japan, Honshu, Kyushu, Shikoku
Korea, DPR
Korea, Republic of
Mongolia
List of countries where planted
Asia
[China] Gansu, Guangdong, Guangxi, Hebei, Liaoning, Nei Menggu, Sichuan, Taiwan, Xinjiang, Xizhang
Japan Honshu
Korea, DPR
Korea, Republic of
Turkey
Turkmenistan

2.02

http://plants.gardenbed.com/35/3465_pro.asp

The seed requires a period of cold stratification

2.03

(1)CAB International, (2000) Forestry Compendium Global Module. Wallingford, UK: CAB International. (2)http://hort.ifas.ufl.edu/trees/JUNCHIA.pdf (3)http://plants.gardenbed.com/35/3465_pro.asp

(1)Approximate limits north to south: 40°N to 25°N
Climate descriptors
- Altitude range: 300 - 2700 m
- Mean annual rainfall: 300 - 630 mm
- Rainfall regime: summer
- Dry season duration: 5 - 8 months
- Mean annual temperature: -1 - 22ºC
- Mean maximum temperature of hottest month: 15 - 22ºC
- Mean minimum temperature of coldest month: -23 - -5ºC
- Absolute minimum temperature: > -41ºC (2)USDA hardiness zones: 5B through 11 (3)Habitat: Near seashores in C. and S. Japan

2.04

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

Natural latitude range
Approximate limits north to south: 40°N to 25°N
List of countries with natural populations
Asia
[China] Anhui, Fujian, Gansu, Guizhou, Hebei, Henan, Hubei, Hunan, Jiangxi, Nei Menggu, Shaanxi, Shanxi, Xizhang, Yunnan
Japan, Honshu, Kyushu, Shikoku
Korea, DPR
Korea, Republic of
Mongolia
List of countries where planted
Asia
[China] Gansu, Guangdong, Guangxi, Hebei, Liaoning, Nei Menggu, Sichuan, Taiwan, Xinjiang, Xizhang
Japan Honshu
Korea, DPR
Korea, Republic of
Turkey
Turkmenistan

2.05

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

List of countries where planted ( * not native range)
Asia
[China] Gansu, Guangdong, Guangxi, Hebei, Liaoning, Nei Menggu, Sichuan, Taiwan, Xinjiang, Xizhang
Japan Honshu
Korea, DPR
Korea, Republic of
Turkey
Turkmenistan

3.01

no evidence

3.02

no evidence

3.03

no evidence

3.04

http://hort.ifas.ufl.edu/trees/JUNCHIA.pdf

Invasive potential: little, if any, potential at this time

3.05

Johnson, P.; Gerbolini, A.; Ethridge, D.; Britton, C.; Ueckert, D. (1999) Economics of redberry juniper control in the Texas Rolling Plains. Journal of Range Management, 1999, Vol.52, No.6, pp.569-574, 18 ref.

AB: Redberry juniper (Juniperus pinchotii ) is a common invasive brush species that reduces rangeland productivity over vast areas in the Rolling Plains and Edwards Plateau regions of Texas, USA. The objectives of this study were to evaluate the economic feasibility of redberry juniper control and determine the optimum treatment cycle for maintenance burning. A response equation was used to estimate the relationship between herbage production and redberry juniper canopy. Data to estimate the relationship was obtained for a site in the Texas Rolling Plains. The analysis used chaining as the initial treatment and periodic prescribed burns as maintenance treatments. Additional livestock production resulting from brush treatments and the costs of treatments were estimated and used to calculate net present values of the investment in brush control over a 30-year period. Net present values indicated that juniper control was economically feasible across a wide range of economic and environmental conditions. Prescri

4.01

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

"the juvenile needle-like leaves occur in whorls of 3 or in decussate pairs, about 8-12 mm long, with a green midrib above and two blue-white stomatal bands, apex prickly. " [not harmful to humans or animals]

4.02

no evidence

4.03

no evidence

4.04

http://www.msue.msu.edu/imp/modwl/11209806.html

seldom damaged by deer

4.05

no evidence

4.06

Lee, D. H. (1990) Studies on the several factors in relation to pear rust infection caused by Gymnosporangium asiaticum Miyabe et Yamada. Korean Journal of Plant Pathology, 1990, Vol.6, No.1, pp.65-72, 17 ref.

AB: "Telia of G. asiaticum on the Juniperus chinensis cv. Kaizuka reached 50% maturity 3-6 d before full bloom of the oriental pear cv. Jangsiprang. "

4.07

no evidence

4.08

possibly, foliage is probably flamable

4.09

(1)CAB International, (2000) Forestry Compendium Global Module. Wallingford, UK: CAB International. (2)http://hort.ifas.ufl.edu/trees/JUNCHIA.pdf
(3)http://edis.ifas.ufl.edu/BODY_MG344 (4)http://msucares.com/pubs/pub666-6.htm

(1)"J. chinensis is a light-demanding species although somewhat tolerant to shade." (2)grows in part shade/part sun;Growing best in full sun, more open in partial shade (3)Full sun (4)Full sun, not part shade

4.1

(1) CAB International, (2000) Forestry Compendium Global Module. Wallingford, UK: CAB International.
(2) Dehgan, B. (1998) Landscape Plants for Subtropical Climates. University Press of Florida., Gainesville, FL. 638pp. P.28 (3)http://hort.ifas.ufl.edu/trees/JUNCHIA.pdf

(1) Descriptors
- Soil texture: medium
- Soil drainage: free
- Soil reaction: neutral
- Special soil tolerances: shallow; infertile
(2) fertile, well-drained soils, will not tolerate wet feet (3)Juniper needs well-drained soil or it will decline from root rot. It tolerates alkaline soil

4.11

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

"J. chinensis is a large, evergreen tree reaching a height of 30 m and a diameter of 3.5m. "

4.12

no evidence

5.01

terrestrial

5.02

tree; Cupressaceae

5.03

no evidence

5.04

tree

6.01

no evidence

6.02

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

"J. chinensis is mainly propagated by seed, cutting and air layering, and occasionally by grafting onto Platycladus orientalis. "

6.03

Due, A. le; Adams, R. P.; Zhong Ming (1999) Using random amplification of polymorphic DNA for a taxonomic reevaluation of Pfitzer junipers. HortScience, 1999, Vol.34, No.6, pp.1123-1125, 18 ref.

AB: Van Melle (1947) proposed that juniper cultivars of the Pfitzer Group were of hybrid origin and ascribed the name Juniperus x media Melle. This purported hybrid of J. chinensis x J. sabina has not been accepted unanimously by the horticultural community. Random amplified polymorphic DNAs (RAPDs) were used to analyse and establish new evidence for the hybrid origin of the Pfitzer Group, using both parents and seven cultivars of the Pfitzer Group. Principal coordinate analysis (PCO) of 122 RAPD bands demonstrated that samples of J. chinensis cluster tightly together, as do the J. sabina samples. Cultivars of the Pfitzer Group lacked affinity with either species, but stood apart as a distinct cluster. The data support Van Melle's conclusion that the Pfitzer Group is separate from J. chinensis and indicate hybrid origin from parents J. chinensis and J. sabina . Juniperus x pfitzeriana (Späth) Schmidt [Pfitzer Group] is recognised as the correct name for cultivars of Pfitzer junipers. Juniperus x media , prop

6.04

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

"J. chinensis is dioecious"

6.05

no evidence

6.06

no evidence

6.07

http://tncweeds.ucdavis.edu/esadocs/documnts/junivir.html

some trees will bear seeds at 10 years [data for related J. virginiana]

7.01

no evidence

7.02

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

"It has been widely planted as an ornamental in southern Nei menggu, Hebei, Shanxi, Shandong, Henan and Shaanxi Province, and around the world in temperate climates."

7.03

no evidence

7.04

Dehgan, B. (1998) Landscape Plants for Subtropical Climates. University Press of Florida., Gainesville, FL. 638pp. P.28

"seeds not winged"

7.05

no evidence

7.06

(1)Dehgan, B. (1998) Landscape Plants for Subtropical Climates. University Press of Florida., Gainesville, FL. 638pp. P.28 (2)http://hort.ifas.ufl.edu/trees/JUNCHIA.pdf

(1)"Subglobose cones, to 0.25 inch in diameter, 2-3 seeded, whitish blue turning brown to purplish brown, often glaucous " (2)Fruit covering: dry or hard, does not attract wildlife; [not typical for bird-dispersal]

7.07

possibly cones are carried by ground-dwelling mammals

7.08

no evidence

8.01

Dehgan, B. (1998) Landscape Plants for Subtropical Climates. University Press of Florida., Gainesville, FL. 638pp. P.28

"Subglobose cones, to 0.25 inch in diameter, 2-3 seeded, whitish blue turning brown to purplish brown, often glaucous " [few seeds in each slowly matured fruit]

8.02

(1) http://plants.gardenbed.com/35/3465_pro.asp (2)http://tncweeds.ucdavis.edu/esadocs/documnts/junivir.html

(1)The seed requires a period of cold stratification. The seed has a hard seedcoat and can be very slow to germinate, requiring a cold period followed by a warm period and then another cold spell, each of 2 - 3 months duration. The seed is best sown as soon as it is ripe in a cold frame. Some might germinate in the following spring, though most will take another year. (2) Delayed germination is caused by embryo dormancy and possibly by an inpermeable seedcoat." (Folwells 1965) [data for related J. virginiana]

8.03

http://tncweeds.ucdavis.edu/esadocs/documnts/junivir.html

Most herbicides are ineffective or erratic in control [data for related J. virginiana]

8.04

http://tncweeds.ucdavis.edu/esadocs/documnts/junivir.html

It does not resprout after complete cutting or burning (Arend 1950), very susceptible to fire destruction [data for related J. virginiana]

8.05

no evidence