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

Sansevieria trifasciata Prain (Variegated snake plant, mother-in-law's tongue, viper's bowstring hemp)

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

y

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

2

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

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

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

y

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

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

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

y

6.07

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

See left

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

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

8.05

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

y=-1, n=1

Total score:

9

Notes

Source

1.01

No evidence

1.02

(1)Native range: Tropical Africa, now widely cultivated and naturalized. (2)naturalized elsewhere

(1)http://www.hear.org/pier/species/sansevieria_trifasciata.htm (2)http://www.ars-grin.gov/cgi-bin/npgs/html/tax_search.pl?Sansevieria+trifasciata

1.03

No evidence

2.01

(1)Origin: Zaire (2)Native range: Tropical Africa, now widely cultivated and naturalized. (3)natural habitat of the northern and southern deserts of the Lost Lands. It is not so common in the drier deserts of Nujel'm.

(1)http://www.desert-tropicals.com/Plants/Agavaceae/Sansevieria_trifasciata.html (2)http://www.hear.org/pier/species/sansevieria_trifasciata.htm (3)http://www.dragon-rune.net/UO/plants/plants.htm

2.02

2.03

(1)Hardiness: USDA zone 9B - 11. (2)natural habitat of the nothern and southern deserts of the Lost Lands. It is not so common in the drier deserts of Nujel'm. [restricted to dry habitats in nature]

(1)http://www.tropilab.com/snakeplant.html (2)http://www.dragon-rune.net/UO/plants/plants.htm

2.04

(1)Origin: Zaire (2)Native range: Tropical Africa, now widely cultivated and naturalized.

(1)http://www.desert-tropicals.com/Plants/Agavaceae/Sansevieria_trifasciata.html (2)http://www.hear.org/pier/species/sansevieria_trifasciata.htm

2.05

Native range: Tropical Africa, now widely cultivated and naturalized.

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

3.02

No evidence

3.03

No evidence

3.04

(1)"The most abundant invasive ornamental weeds were Agave spp. (sisal or agave), Asparagus densiflorus (asparagus fern), Bryophyllum spp. (mother-of-millions), Catharanthus roseus (pink periwinkle), Euphorbia cyanthophora (dwarf poinsettia), Gloriosa superba (glory lily), Lantana camara (lantana), Opuntia stricta (prickly pear), Sansevieria trifasciata (mother-in-law's tongue), Schinus terebinthifolia [S. terebinthifolius] (Brazilian pepperina tree) Senna pendula var. glabra (Easter cassia) and Wedelia trilobata (Singapore daisy). " (2)Environmental weed of unknown importance, Queensland (3)Environmental Weeds of South East Queenslalnd

(1)Batianoff, G. N. , Franks, A. J. (1997) Invasion of sandy beachfronts by ornamental plant species in Queensland. Plant Protection Quarterly, 1997, Vol. 12, No. 4, pp. 180-186, 26 ref. (2)RANDALL, R. 2001. Garden thugs, a national list of invasive and potentially invasive garden plants. Plant Protection Quarterly 16: 138-171. (3)http://www.nrm.qld.gov.au/pests/environmental_weeds/pdf/specieslist.pdf

3.05

(1)"The Sansevieria hyacinthoides is relatively easy to grow in Phoenix. It is considered an invasive weed in Florida.
" (2)Sansevieria hyacinthoides Category II Invasive plant in Florida

(1)http://www.desert-tropicals.com/Plants/Agavaceae/Sansevieria_hyacinthoides.html (2)http://www.fleppc.org/Plantlist/03list.htm

4.01

No evidence of such structures.

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

4.02

No evidence

4.03

No evidence

4.04

Don’t know

4.05

(1)This site lists Sasevieria as toxic (minor and dematitis) plant to animals. (2)Snake Plant, Mother-in-law Tongue—(Sansevieria trifasciata) non-toxic.

(1)http://www.therustydog.com/Resources/Health/ (2)http://lancaster.unl.edu/factsheets/031.htm

4.06

(1)Opogona sacchari Boj. is a recognized pest (2)O. sacchari has a wide host range, and is found mainly in the tropics on bananas, pineapples, bamboo, maize and sugarcane, in the field and on various stored tubers. In glasshouses in European countries, it has been found infesting various tropical or subtropical ornamentals, including mainly Cactaceae, Dracaena, Strelitzia and Yucca, but also occasionally Alpinia, Begonia, Bougainvillea, Bromeliaceae, Chamaedorea and other palms, Cordyline, Dieffenbachia, Euphorbia pulcherrima, Ficus, Gloxinia, Heliconia, Hippeastrum, Maranta, Philodendron, Sansevieria and Saintpaulia, and also Capsicum and aubergines. In import inspections, it is mainly Dracaena and Yucca which have been found to be infested. [wide range]

(1) Clercq, R. De , Luchene, I. Van (1977) Occurrence and control of the caterpillars of Opogona sacchari Boj. on Dracaena fragrans and Sansevieria trifasciata 'Laurentii'. Verbondsnieuws voor de Belgische Sierteelt, 1977, Vol. 21, No. 15, pp. 499, 501, 7 ref. (2) http://flrec.ifas.ufl.edu/entomo/BugBites/bbv2n1.htm (2)http://www.vaxteko.nu/html/sll/eppo/EDS/E-OPOGSC.HTM

4.07

(1) 'Mode-Ingestion, dermatitis. Poisonous Part All parts; of low risk. Symptoms Excessive salivation; skin irritation. Toxic Principle Possibly saponins and organic acids. Severity CAUSES ONLY LOW TOXICITY IF EATEN. SKIN IRRITATION MINOR, OR LASTING ONLY FOR A FEW MINUTES. (2)Snake Plant, Mother-in-law Tongue—(Sansevieria trifasciata) non-toxic.

(1)http://www.ces.ncsu.edu/depts/hort/consumer/poison/Sansetr.htm (2)http://lancaster.unl.edu/factsheets/031.htm

4.08

a perennial succulent.

http://www.horticopia.com/hortpix/html/pc4817.htm

4.09

(1)They tolerate the low light conditions. (2)Sun Exposure: Light shade (3)normally preferring shady areas to direct sunlight (4)we grow ours under 52% shade

(1)http://www.plantoftheweek.org/week192.shtml (2)http://www.desert-tropicals.com/Plants/Agavaceae/Sansevieria_trifasciata.html (3)http://www.dragon-rune.net/UO/plants/plants.htm (4)http://www.plantoftheweek.org/week210.shtml

4.1

Soil tolerances: alkaline; clay; sand; acidic; loam

http://216.239.57.104/search?q=cache:vkUZrvO8HLoJ:hort.ifas.ufl.edu/shrubs/SANTRIB.PDF+Sansevieria+trifasciata&hl=en

4.11

No evidence

4.12

No evidence

5.01

Agavaceae

5.02

Agavaceae

5.03

Agavaceae

5.04

Herb with rhizomes.

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

6.01

No evidence

6.02

(1)Propagation: Seed, rhizomes (2) Although several species can be propagated from seed, this technique is not employed because the large number of seeds needed by commercial growers is not available and normally plants can be produced faster by cutting or division.

(1)http://www.hear.org/pier/species/sansevieria_trifasciata.htm (2)http://www.mrec.ifas.ufl.edu/Foliage/folnotes/sansevie.htm

6.03

Sansevieria 'Druid Hill' is my hybrid between Sans.trifasciata 'Manda's Dwarf' and Sans.suffruticosa ssp. longituba 'Bally 12681' that I made while at the Druid Hill Conservatory...Therefore S. t. 'Stellette'is a hybrid between S. trifasciata ans probably S.aethiopica.

http://article.gmane.org/gmane.plants.sansevieria/158

6.04

Don’t know

6.05

Photo of flowers. [with narrow corolla tube, appears specialized]

(1)http://www.hear.org/pier/imagepages/singles/satrip77.htm (2)http://davesgarden.com/pdb/showimage/2911/

6.06

(1)Propagation: Sansevieria trifasciata "Laurentii" are propagated by division of rhizomes at anytime of the year. (2)In Hawai`i, "spread vegetatively from areas where they are cultivated.

(1)http://www.plantoftheweek.org/week192.shtml (2)http://www.hear.org/pier/species/sansevieria_trifasciata.htm

6.07

Don’t know

7.01

no evidence that the propagules have any means of attachemnt.

7.02

Bird’s Nest is occasionally used in the landscape as aground cover, especially in dry, desert-like gardens. Theirsmall size and drought tolerance makes them suited for a rockgarden. It is also very attractive when used in containers placedindoors or outdoors

http://216.239.57.104/search?q=cache:vkUZrvO8HLoJ:hort.ifas.ufl.edu/shrubs/SANTRIB.PDF+Sansevieria+trifasciata&hl=en

7.03

no evidence that the species grows in or around farms - no evidence that the speceis is an agricultural weed.

7.04

fruit is a bery with fleshy seeds.

(1)http://www.tropilab.com/snakeplant.html (2)http://www.hear.org/pier/species/sansevieria_trifasciata.htm (3)http://216.239.57.104/search?q=cache:vkUZrvO8HLoJ:hort.ifas.ufl.edu/shrubs/SANTRIB.PDF+Sansevieria+trifasciata&hl=en

7.05

no evidence that the species inhabits waterways.

7.06

(1)It produces a berry as the fruit. (2)fruit a small globose orange berry with fleshy seeds (3)Fruit shape: ovalFruit length: less than .5 inchFruit cover: fleshyFruit color: redFruit characteristic: persists on the plant

(1)http://www.tropilab.com/snakeplant.html (2)http://www.hear.org/pier/species/sansevieria_trifasciata.htm (3)http://216.239.57.104/search?q=cache:vkUZrvO8HLoJ:hort.ifas.ufl.edu/shrubs/SANTRIB.PDF+Sansevieria+trifasciata&hl=en

7.07

No evidence that the propagules have any means of attachment.

7.08

(1)It produces a berry as the fruit. (2)fruit a small globose orange berry with fleshy seeds (3)Fruit shape: ovalFruit length: less than .5 inchFruit cover: fleshyFruit color: redFruit characteristic: persists on the plant

(1)http://www.tropilab.com/snakeplant.html (2)http://www.hear.org/pier/species/sansevieria_trifasciata.htm (3)http://216.239.57.104/search?q=cache:vkUZrvO8HLoJ:hort.ifas.ufl.edu/shrubs/SANTRIB.PDF+Sansevieria+trifasciata&hl=en

8.01

relatively large propagule size. Fruit about 0.5 inch long.

(1)http://www.tropilab.com/snakeplant.html (2)http://www.hear.org/pier/species/sansevieria_trifasciata.htm (3)http://216.239.57.104/search?q=cache:vkUZrvO8HLoJ:hort.ifas.ufl.edu/shrubs/SANTRIB.PDF+Sansevieria+trifasciata&hl=en

8.02

No evidence regarding seedbank.

8.03

At present there are no herbicides labeled for use on sansevieria beds which selectively kill established weeds without damaging the crop.

http://www.mrec.ifas.ufl.edu/Foliage/folnotes/sansevie.htm

8.04

Don’t know

8.05

Don’t know