Pacific Island Ecosystems at Risk (PIER)

Dasylirion acrotrichum


Australian/New Zealand Weed Risk Assessment adapted for Hawai‘i.
Information on Risk Assessments
Original risk assessment
  Dasylirion acrotrichum [green desert spoon] (Synonym: Yucca acrotricha, Dasylirion acrotriche, Dasylirion gracile, Bonapartea gracile, Roulinia gracile, Yucca gracile) Previously Agavaceae - now Nolinaceae. Answer Score
1.01 Is the species highly domesticated? n 0
1.02 Has the species become naturalized where grown? n  
1.03 Does the species have weedy races? 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” 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
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 n -2
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) n 0
3.05 Congeneric weed                                                          y = 1*multiplier (see Append 2) n 0
4.01 Produces spines, thorns or burrs y 1
4.02 Allelopathic n 0
4.03 Parasitic n 0
4.04 Unpalatable to grazing animals    
4.05 Toxic to animals n 0
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) n 0
4.11 Climbing or smothering growth habit n 0
4.12 Forms dense thickets n 0
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    
6.04 Self-compatible or apomictic n -1
6.05 Requires specialist pollinators    
6.06 Reproduction by vegetative fragmentation n -1
6.07 Minimum generative time (years)                 1 year = 1, 2 or 3 years = 0, 4+ years = -1 4 -1
7.01 Propagules likely to be dispersed unintentionally (plants growing in heavily trafficked areas) y 1
7.02 Propagules dispersed intentionally by people y 1
7.03 Propagules likely to disperse as a produce contaminant n -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 n 1
8.04 Tolerates, or benefits from, mutilation, cultivation, or fire    
8.05 Effective natural enemies present locally (e.g. introduced biocontrol agents)    
  Total score:   0

Supporting data:

  Notes Reference
1.01 No evidence  
1.02 No evidence  
1.03 No evidence  
2.01 Origin: East-central Mexico (Durango, Tamaulipas, Jalisco)
2.03 (1)USDA: 9-11  (2)Several Missouri Botanical Garden herbarium specimens obtained from elevation above 2000 m. mostly from Mexico. (1)  (2)
2.04 Origin: East-central Mexico (Durango, Tamaulipas, Jalisco)
2.05 (1)Introduced to the United States. (a)Seeds available for sale online from the following website  - this physical address to obtain seeds from this site is: FutureSystems 1700 Bittersweet Hill Vista, CA 92084. (b) Also available online from  - their plant nursery is located in Phoenix, Nevada.(2)Available for sale from the Trevena Cross Nursery in Cornwall - England. (3)Introduced to England - Sussex (2) (3)
3.01 No evidence  
3.02 Is on the list of 'near-native accent plants' in Civano,Arizona.
3.03 No evidence  
3.04 No evidence [Listed on Official Regulatory List For: Arizona Department of Water Resources - as an accent plant with low water use/ drought tolerance that is not invasive.]
3.05 No evidence [D. wheeleri is a native congener recommended for plantings in place of invasive specesi such as fountain grass in the Sonoran desert].
4.01 The leaf margins have small recurved spines. (1)  (2)
4.02 No evidence  
4.03 No evidence  
4.04 Probably not - succulent leaves with spines on the margins. (1) '...The shrubs least preferred by goats were not affected (A. pringlei, Gutierrezia sarothrae and Dasylirion wheeleri), while preferred browse …' - [D. wheeleri is very similar to D. acrotrichum and probably is not preferred by goats either.] (1)Influence of Spanish goats on vegetation and soils in Arizona chaparral  . By: Severson, K. E.;  Journal of Range Management 44 (2), 1991, p.111-117 (Journal article)
4.05 No evidence  
4.06 The following two speceis of fungi were listed to be associated with D. acrotrichum, however there is no evidence that they are of economic importance - Phomopsis gloriosa and Metasphaeria dasylirii. Farr, D.F., Rossman, A.Y., Palm, M.E., & McCray, E.B. (n.d.) Fungal Databases, Systematic Botany & Mycology Laboratory, ARS, USDA. Retrieved June 29, 2006, from
4.07 No evidence  
4.08 Although the plant is a succulent, the accumulation of dead leaves might pose a fire hazard. (See photo) (1)
4.09 (1)Sun Exposure: Full sun, tolerates reflected heat  (2)Demands a well drained sunny site. (1)  AND  (2)
4.1 Probably not - 'Plant in very fast draining soil and provide little or no water in winter. Treat like a succulent.'
4.11 Growth Habits: Evergreen shrub, up to 6 feet tall.
4.12 No evidnece  
5.01 Growth Habits: Evergreen shrub, up to 6 feet tall.
5.04 No evidence  
6.01  'Dasylirion form a genus of 18 varieties native to the desert areas of southern USA and Mexico. Dasylirion usually form a single short trunk topped by an almost spherical head of leaves. Mature plants produce huge flower stock covered in flowers similar to yucca. ... Dasylirion acrotriche grows to 4-5 feet tall and wide, forming a dense rosette of green foliage. Over time it develops a stout short trunk. The leathery 2 to 3 foot long, ½ inch wide leaves have teeth along the margins and a spoon-shaped base that gives the plant its name. Desert spoon produces a narrow 9 to 15 foot-tall stalk covered with thousands of tiny greenish-yellow flowers.'
6.02 (1)Propagation by seeds.  (2)The seeds are available from '' - they guarantee vaibility of seeds. (1)
Agavaceae/Dasylirion_acrotriche.html (2)
6.03 Dont know -  'Dasylirion leiophyllum (Sotol) in the "Green Gulch" of the Chisos Mountains, Big Bend National Park, Texas. Although sufficiently mature to flower, these rosettes are stem-less. The hooked teeth on the leaf margins of this species curve towards the base of the leaves.
Where its range overlaps with D. texanum, hybrids with intermediate morphology occur and the marginal teeth may point towards the leaf base, leaf tip or straight out. ' - [however no evidence regarding D. acrotriche hybrids].
6.04 (1)Some ssp. are almost stemless or have short trunks up to 5ft. Some ssp. Have trunks up to 9-10 ft.The leaves of Dasylirion are linear and long with different colours, ranging from dark glossy green or blue-gray to yellow-green.
On the inflorescence, thousands of tiny cream-coloured flowers develop, with male and female flowers on separate plants. (2)Unlike most Agaves, all members of the family Nolinaceae. are polycarpic and dioecious, with decorative spikes of numerous small creamy-white flowers, sometimes tinged with pink or purple.
(1)  (2)
6.05 Don’t know.  
6.06 No evidence of spread by vegetative means.  
6.07 This lovely Mexican species has proven hardy to 8 degrees in our zone 7b garden, despite books that proclaim it to be a Zone 9 plant. Each 4' wide rosette of narrow green foliage will eventually find itself atop a 4' tall trunk. Be sure to plant this prior to puberty (yours), if you really want to see a full-size trunk before you die. Our 10 year-old specimens are 3' tall x 4' wide, but showing no sign of a trunk The unique feature of D. acrotrichum is the attractive, frayed leaf tips that are especially evident in winter...a truly bad plant hair day! '
7.01 Probably yes - an ornamental plant grown for its  
7.02 Probably yes - the seeds are availabel online from the following websites - (1)  (2) (1) (2)
7.03 Probably not - no evidence that the species grows along side plants fields of economically important crops or orchards.  
7.04 Genus characteristics - "Fruits capsular, 1-locular, dry, indehiscent, 3-winged. Seed 1, golden brown, 3-angled, turbinate. x = 19." [Probably yes - Turbinate shaped seeds suggests a mechanism for dispersal by wind]
7.05 No evidence that the species inhabits waterways - adapted to dry regions.  
7.06 Probably not - fruit is capsule.  
7.07 Probably not - no evidence that the propagules have any means of dispersal.  
7.08 Probably not - no evidence of ingestion.  
8.01 Desert spoon produces a narrow 9 to 15 foot-tall stalk covered with thousands of tiny greenish-yellow flowers.
8.02 No evidence regarding seed longevity.  
8.03 No evidence that the species is being controlled for.  
8.04 Don’t know.  
8.05 Don’t know.  

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This page was created on 23 December 2006 by JS and was last updated on 04 June 2017 by PT.