Ver. 1 (Original) September 5, 2012 0

Importation of fresh edible flowers of Izote (Yucca 

guatemalensis Baker) into the continental United States from 

Guatemala

A Pathway-Initiated Risk Assessment

Version 1

September 5, 2012

Agency Contact

Center for Plant Health Science and Technology

Plant Epidemiology and Risk Analysis Laboratory

United States Department of Agriculture

Animal and Plant Health Inspection Service

Plant Protection and Quarantine

1730 Varsity Drive, Suite 300

Raleigh, NC 27606
Ver. 1 (Original) September 5, 2012 ii

Executive Summary

The Animal and Plant Health Inspection Service (APHIS) of the United States Department of 

Agriculture (USDA) prepared this risk assessment document to examine plant pest risks 

associated with importing fresh flowers of izote (Yucca guatemalensis Baker) from Guatemala 

into the continental United States. We prepared a list of pests associated with izote in Guatemala 

based on documentation submitted by the Ministry for Agriculture and Livestock and Food of 

Guatemala, scientific literature, records of intercepted pests at ports-of-entry, and the opinions of 

experts in the field on izote production. 

We identified one pest, the gray pineapple mealybug (Dysmicoccus neobrevipes Beardsley), as a 

quarantine pest that may follow the pathway and be introduced with negative consequences if not 

mitigated with specific phytosanitary measures. The Pest Risk Potential for D. neobrevipes was 

Medium.

Identification and selection of appropriate sanitary and phytosanitary measures to mitigate risk 

for pests with particular Pest Risk Potential ratings are undertaken as part of the risk-management 

phase and is not discussed in this document. 
Ver. 1 (Original) September 5, 2012 iii

Table of Contents

Executive Summary ...................................................................................................................... ii

1. Introduction ................................................................................................................................1

1.1. Background.............................................................................................................................1

1.2. Commodity information .........................................................................................................1

2. Risk Assessment..........................................................................................................................2

2.1. Initiating Event: Proposed Action...........................................................................................3

2.2. Assessment of Weed Potential of Yucca guatemalensis.........................................................3

2.3. Current Status, Decision History and Pest Interceptions........................................................4

2.4. Pest Categorization—Identification of Pests of Izote in Guatemala ......................................4

2.5. Quarantine Pests Likely to Follow the Pathway.....................................................................7

2.6. Consequences of Introduction ................................................................................................7

2.7. Likelihood of Introduction......................................................................................................9

2.8. Pest Risk Potential and Conclusion ......................................................................................10

3. Literature Cited........................................................................................................................11

4. Preparers and Reviewers.........................................................................................................14

5. Appendices................................................................................................................................15

Appendix A. Pests intercepted on Yucca guatemalensis from 1985 to 2004 ..............................15

Appendix B. Plant species related to families of hosts of Dysmicoccus neobrevipes listed by the 

U.S. Fish and Wildlife Service considered as endangered or threatened. ...................................16
Ver. 1 (Original) September 5, 2012 1

1. Introduction

1.1. Background

This risk assessment was prepared by the United States Department of Agriculture (USDA), 

Animal and Plant Health Inspection Service (APHIS), Plant Protection and Quarantine (PPQ), 

Center for Plant Health Science and Technology (CPHST), Plant Epidemiology and Risk 

Analysis Laboratory (PERAL). Our purpose was to examine pest risks associated with the 

importation of Izote Yucca guatemalensis Baker as fresh fruit from Guatemala into the 

continental United States. This risk assessment examined the pest risk of commercial quality

izote, which undergoes cleaning and washing of sap of each individual fruit as part of standard 

post-harvest treatment. 

Plant pest risks associated with the importation of fresh fruit of Izote from Guatemala into the 

United States were estimated and assigned the qualitative terms of high, medium or low, in 

accordance with the template document, Guidelines for Pathway-Initiated Pest Risk Assessments, 

Version 5.02 (PPQ, 2000).

Regional and international plant protection organizations such as the North American Plant 

Protection Organization (NAPPO) and the International Plant Protection Convention (IPPC) 

provide standards for conducting pest risk analyses (IPPC, 2009: ISPM #s 11; NAPPO, 2004). 

The use of biological and phytosanitary terms is consistent with the ‘Glossary of Phytosanitary

Terms and the Compendium of Phytosanitary Terms’ (IPPC, 2009: ISPM #5). The methods used 

to initiate, conduct, and report this assessment, as well as the use of biological and phytosanitary

terms are based on these standards. The IPPC standards describe three stages of pest risk 

analysis: Stage 1, Initiation; Stage 2, Risk Assessment; and Stage 3, Risk Management. This 

document satisfies the requirements of IPPC Stages 1 and 2.

1.2. Commodity information

Yucca guatemalensis Baker (Class: Monocotyledonae, Order: Asparagales, Family: Agavaceae) 

is native to the southwestern United States, Puerto Rico, Mexico, and Guatemala (Bartolomaus et 

al., 1990; Gardening Australia, 2000; Sanchez de Lorenzo, 2003; USDA and NRCS, 2002). Izote 

belongs to the Yucca genus, which includes approximately 40 species, distributed mainly in the 

United States, Mexico, Central America, and Cuba (Nuñez, 1994). The synonym Yucca 

elephantipes is commonly cited for this species in several documents and in databases in 

Guatemala and Central America.

Yucca guatemalensis is known as izote in Guatemala, and is also called spineless or giant yucca. 

Its leaves are pliable and lack the sharp spines on the tips that are characteristic of most yuccas. 

The plant may reach a height of 9.1m (30 ft) (USDA and NRCS. 2002). With age the stem 

becomes rough and thick, and when mature it develops a swollen base and often branches a few 

feet off the ground. The leaves, which grow in a spiral rosette, are shiny green, reaching 1.2m (4

ft) in length and close to 7.6 cm (3 in) in width, with serrated margins (Bailey and Bailey, 1976; 

Christman, 2002). Izote grows in arid regions of southern Mexico and Central America.
Ver. 1 (Original) September 5, 2012 2

The inflorescence is an erect panicle 60-70 cm (23.62-27.56 in.) long, with distinct white,

fragrant flowers with 1 to 2 (Grayum, 2003; Nuñez, 1994). The stamens are attached right under 

the ovary. The flowers are white or pale yellow and correspond to a clustered inflorescence. In 

Guatemala, budding occurs when the plant reaches 4 to 7 years of age. Inflorescences appear at 

the beginning of the rainy season (April, May) and generally one inflorescence per stem is 

formed (Bartolomaus et al., 1990; Nuñez, 1994).

The flowers of izote are edible and, in Guatemala, are consumed cooked or stewed with eggs or 

pickled. The flowers contain calcium, iron, thiamine, niacin, phosphorus, carotene, and ascorbic 

acid (Nuñez, 1994). 

Figure 1. (a) Izote Inflorescence (CEF, 2005). (b) Packed izote flowers (CEF, 2005).

2. Risk Assessment

In this risk assessment, the first five Risk Elements considered are combined to form an 

assessment of the risk associated with the Consequences of Introduction. Six Sub-Elements are 

evaluated and combined for value that estimate the risk associated with the Likelihood of 

Introduction. Together, the Consequences of Introduction and the Likelihood of Introduction 

values form an assessment of the Pest Risk Potential. 
Ver. 1 (Original) September 5, 2012 3

2.1. Initiating Event: Proposed Action

This commodity-based, pathway-initiated assessment is in response to a request made by the 

Ministry for Agriculture, Livestock, and Food of Guatemala (dated March 28, 2011) to the 

USDA for authorization to allow the importation of izote. In this case, the importation into the 

continental United States of izote flowers, grown in Guatemala, is a potential pathway for the 

introduction of plant pests. 

2.2. Assessment of Weed Potential of Yucca guatemalensis

The results of the screening for the potential of izote as a weed did not prompt a weed-initiated 

risk assessment (Table 1).

Table 1. Assessment of weed potential of Yucca guatemalensis.

Scientific name and author: Yucca guatemalensis Baker

Plant family: Agavaceae

Synonyms: Yucca elephantipes Regel; Y. gigantea Baker; Y. ghiesbreghtii Baker; Y. 

lenneana Baker; Y. mazelii Hort. ex Watson; Y. mooreana Hort. Peacock ex Baker; Y. roezlii

Hort. ex Baker. (Etter and Kristen, 1997-2004; FACTOPIA, 2005; Moller, 1998-2003).

Common names: Bayoneta, Bluestem yucca, Elephant yucca, Flor de itabo, Hitavo, Izote, 

Palmito, Soft-Tip Yucca, Spineless yucca (CABI, 2012 Gilman and Watson, 1994; Randall 

et al., 2002; Grayum, 2003; World Agroforestry Centre, 2005)

Phase 1:

This plant is native to the southwest United States (Bartolomaus et al., 1990). This species 

reportedly occurs in Belize, Costa Rica, Ecuador, Guatemala, Mexico, Nicaragua, and the 

United States (GDIF, 2005).

Phase 2:

NO Geographical Atlas of World Weeds (Holm et al., 1991a).

NO The World’s Worst Weeds (Holm et al., 1991b).

NO Report of the Technical Committee to Evaluate Noxious Weeds; Exotic Weeds for 

the Federal Noxious Weed Act (APHIS, 2000).

NO Economically Important Foreign Weeds (Reed, 1977).

NO Weed Science Society of America, 2005.

NO AGRICOLA (AGRIS/CARIS, 2005).

NO Alien Plant Invaders of Natural Areas (Swearingen, 2003).

Other literature and database search indicating weediness:

NO World weeds: natural histories and distributions (Holm et al., 1997).

NO World Economic Plants (Wiersema and León, 1999).

NO Florida’s Invasive Species List, Florida Exotic Pest Plant Council (FLEPPC, 2003).

NO CABI, 2012 Crop Protection Compendium. Search on Weed.

Phase 3:

A weed-initiated risk assessment is not initiated for Yucca guatemalensis because there is no 

evidence of invasive behavior by this plant within the literature and due to the fact that the 

responses to the above were negative.
Ver. 1 (Original) September 5, 2012 4

2.3. Current Status, Decision History and Pest Interceptions 

Currently, the exportation of fresh flowers of izote for consumption into the United States from 

Guatemala is not permitted (USDA, 2005).

A number of pests have been intercepted on izote entering the United States, but most were not 

identified to species level (see Appendix A).

2.4. Pest Categorization—Identification of Pests of Izote in Guatemala

In Table 2, we present information on the geographic distribution, host associations, and 

regulatory data for izote from Guatemala. We listed (1) the presence of pests in Guatemala 

relative to their presence within the United States, (2) the generally affected plant part or parts, 

(3) the quarantine status of the pest in the United States, (4) whether or not the pest is likely to 

follow the pathway into the United States on izote, and (5) pertinent citations for either the 

distribution or the biology of the pest. Many organisms are not sources of phytosanitary risk on 

izote from Guatemala because they do not satisfy the definition of a quarantine pest. A quarantine 

pest is defined as “A pest of potential economic importance to the area endangered thereby and 

not yet present there, or present but not widely distributed and being officially controlled” (IPPC, 

2009: ISPM No. 5). 

Table 2. Pests associated with Yucca guatemalensis and present in Guatemala.

Pest Scientific Name and 

Taxonomy

Geographic 

distribution1

Plant part 

affected2

Quarantine pestFollow 

pathway

References

ARTHROPODA

Insecta

Coleoptera: Curculionidae

Scyphophorus 

acupunctatus Gyllenhal

GU, US R, S No No Berry, 1959; CABI, 2012; 

Nearctica, 1998

Hemiptera: Diaspididae

Chrysomphalus 

dictyospermi (Mogan)

GU, US F, L, S, Sh No No Ben-Dov et al., 2005; CABI, 

2012

Hemiptera: Pseudococcidae

Dysmicoccus neobrevipes

Beardsley

GU, US 

(FL)

F, Fl, L, R Yes Yes Ben-Dov et al., 2005; 

Kessing and Mau, 1992; 

OIRSA, 2005; Williams and 

Granara, 1992

 

1 Geographic Distribution: CA = Central America, SV = El Salvador, US = United States.

2

Plant Part Affected: Branch= B, Flower= Fl, Fruit= F, Leaf= L, Root= R, Seeds= Se, Seedling= Sd, Shoot= Sh, Stem= S, 

Tuber= T.
Ver. 1 (Original) September 5, 2012 5

Pest Scientific Name and 

Taxonomy

Geographic 

distribution1

Plant part 

affected2

Quarantine pestFollow 

pathway

References

Nipaecoccus nipae 

(Maskell) 

GU, US F, L, S, Sh No No Ben-Dov et al., 2005; CABI, 

2012; Howard et al., 2001; 

Williams and Granara, 1992

Pseudococcus landoi 3

(Balachowsky)

GU F Yes No Ben-Dov et al., 2005; PestID 

2012

BACTERIA

Erwinia spp.

Enterobacteriales

GU S, Sd Yes No Bonilla and Merino, 1988; 

Clark, 1990; FUSADES, 

2005

FUNGI4

Alternaria alternata 

(Fr.:Fr.) Keissl

Syn: A. tenuis Nees

(Mitosporic fungi: 

Hyphomycetes)

GU, US L No No Escobar, 2003; Farr et al., 

1989; Villalobos and 

Cárdenas, 2002

Alternaria sp. (Mitosporic 

fungi: Hyphomycetes)

GU, US L, Sd,F Yes Yes Acuña and Rivera, 1976; 

Farr et al., 1989; McGuire 

and Crandall, 1967; Padilla 

and Palma, 1985

Apodothina pringlei

(Peck)

Syn: Sphaerodothis 

pringlei (Peck) Thiss & 

Syd 

(Loculoascomycetes: 

Dothideales)

GU, US L No No Farr et al., 1989; Wellman, 

1977

Curvularia sp.

(Mitosporic fungi:

Hyphomycetes)

GU L Yes No Acuña and Rivera, 1976; 

Alfieri et al., 1994; Escobar, 

2003; Bonilla and Merino, 

1988; Farr et al., 1989; 

Villalobos and Cárdenas, 

2002

Cytosporina sp.

(Mitosporic fungi: 

Coelomycetes)

GU L Yes No Anonymous, undated; Farr 

et al., 1989; Villalobos and 

Cárdenas, 2002

 

3 The evidence for yucca being a host is ambiguous. Only Ben Dov et al. (2005) mention yucca as a host, while Williams and 

Granara (1992) and Ben-Dov (1994) do not, and their descriptions consistently state that the primary host is banana (Musa

sp). In addition, the only evidence that the mealybug may convey on flowers is from PestID (2012), but the plant part 

descriptions are ambiguous, are found on only one species from one inspector, and are equally likely to be result of data 

entry error as a description of the area where the mealybugs were found. Due to the high likelihood of data error and the 

lack of consistent evidence, we do not analyze this insect.

4

Fungal taxonomic classification as in Farr et al. (1989).
Ver. 1 (Original) September 5, 2012 6

Pest Scientific Name and 

Taxonomy

Geographic 

distribution1

Plant part 

affected2

Quarantine pestFollow 

pathway

References

Fusarium sp. (Mitosporic 

fungi: Hyphomycetes)

GU L, S, Sd Yes Yes Clark et al., 1988; Farr et al., 

1989; Farr et al., 2005; 

Padilla and Palma, 1985; 

González et al., 2001

Glomerella cingulata 

(Stoneman) Spauld. & 

H. Screnk. (Anamorph: 

Colletotrichum 

gloesporoides (Penz.) 

Penz.& Sacc. In Penz)

(Pyrenomycetes: 

Phyllachorales)

GU, US Fl, L No Yes Acuña and Rivera, 1976; 

Farr et al., 1989; McGuire 

and Crandall, 1967; 

Rodríguez, 2003; Villalobos 

and Cárdenas, 2002; 

Wellman, 1977

Sclerotium rolfsii Sacc.

(Mitosporic fungi: 

Agonomycetes)

GU, US R No No Acuña and Rivera, 1976; 

Alfieri et al., 1994; Farr et 

al., 1989; FUSADES, 2005; 

Villalobos and Cárdenas, 

2002

NEMATODA5

Helicotylenchus spp.

(Hoplolaimidae)

GU R Yes No Fernández et al., 2002; 

Ferris, 2001; Padilla and 

Palma, 1985

Meloidogyne spp.

(Heteroderidae)

GU R Yes No CABI, 2006; Fernández et 

al., 2002; Ferris, 2001; 

Padilla and Palma, 1985; 

González et al., 2001

Rotylenchulus reniformis

Linford & Oliveira

(Hoplolaimidae)

GU, US R No No CABI, 2006; Ferreira and 

Boley, 1991; Ferris, 2001

Pratylenchus spp.

(Pratylenchidae)

GU R Yes No Fernández et al., 2002; 

Ferris, 2001; Padilla and 

Palma, 1985

VIRUS

Yucca baciliform 

badnavirus

GU L Yes No Brunt, 1996 onwards

 

5 Nematode taxonomic classification as in Ferris (2001).
Ver. 1 (Original) September 5, 2012 7

2.5. Quarantine Pests Likely to Follow the Pathway

We found one quarantine pest, Dysmicoccus neobrevipes, that is likely to follow the pathway

(i.e., be included in commercial shipments of izote flowers from Guatemala). We found no 

reports of this insect on izote flowers in the worldwide literature, but we analyzed this insect in 

detail because it is reported on Yucca elephantipes, and because biological information about this 

insect indicated it was associated with flowers of other species.

In addition, we found the following pests that were only identified to the genus level: Erwinia

sp., Alternaria sp., Curvularia sp., Cytosporina sp. Fusarium sp., Meloidogyne spp., and 

Pratylenchus spp. Lack of species identification may indicate limited taxonomic knowledge 

about that group, inappropriate life stage for full identification, or poor quality of the specimen. 

This lack of biological information on any given insect or pathogen should not be equated with 

low risk. By necessity, pest risk assessments focus on those organisms for which biological 

information is available and for which effective mitigation procedures may be developed (IPPC, 

2009: ISPM No. 11). Agricultural inspectors at the port-of-entry will continue to take action 

against pests not identified to the species level if other species in the same genus are quarantine 

pests. Furthermore, if pests identified to only higher taxa are intercepted in the future, the USDA 

may re-evaluate their risk. Should any of these pests be intercepted in shipments of izote flowers, 

quarantine action will be taken and additional risk analyses will be conducted.

2.6. Consequences of Introduction

We rated the potential consequences of introduction for D. neobrevipes using five Risk Elements: 

Climate-Host Interaction, Host Range, Dispersal Potential, Economic Impact, and Environmental 

Impact. For each Risk Element, pest is assigned a rating of Low (1 point), Medium (2 points), or 

High (3 points). We then calculated a cumulative risk rating by adding up all of the Risk Element 

values. The ratings for D. neobrevipes for the five risk elements are shown below (Table 3).

Dysmicoccus neobrevipes Beardsley

2.6.1. Climate-Host Interaction

Dysmicoccus neobrevipes is widespread in the following tropical countries: the Bahamas, 

Barbados, Brazil, Colombia, Costa Rica, the Dominican Republic, Ecuador, Guatemala, Haiti, 

Honduras, Jamaica, Mexico, Panama, Peru, Puerto Rico, Suriname, Trinidad and Tobago, and the 

Virgin Islands (in Central and South America) (Ben-Dov et al., 2005; Williams and Granara, 

1992). In the Asian Pacific basin, this species is reported in American Samoa, Fiji, Guam, the 

Hawaiian Islands, Kiribati, the Marshall Islands, the Northern Mariana Islands, and Western 

Samoa. In East Asian countries, it is reported in India, China, Malaysia, Pakistan, the Philippines, 

Singapore, Thailand, and Vietnam, and within the Palearctic region, it is reported in Sicily (BenDov et al., 2005; CABI, 2006; Kessing and Mau, 1992). Some of the aforementioned regions are 

located at latitudes corresponding to plant hardiness zones 8 to 11 of the continental United 

States (USDA-ARS, 2003). Thus, this species may become established within these areas due to 

suitable environmental conditions. Furthermore, within the United States, in Florida, Louisiana, 

Missouri, Arkansas, Colorado, New Mexico, and Tennessee, among others, there are cultivated 

areas of different species that can be hosts of this pest such as Ananas comosus, Citrus 

aurantifolia, Citrus limon, Citrus sinensis, Lycopersicum sculentum, Musa sp., and Zea mays

(Ben-Dov et al., 2005; USDA and NRCS, 2002). Consequently, we rated this element Medium. 
Ver. 1 (Original) September 5, 2012 8

2.6.2. Host Range

The main host for D. neobrevipes is pineapple (Ananas comosus) (Ben-Dov et al., 2005; CABI, 

2006). Nonetheless, several authors report this pest on more than 45 species and 18 genera of 

plants (DAFF, 2004; Kessing and Mau, 1992; Williams and Granara, 1992). On the other hand, 

Ben-Dov et al. (2005) reports this insect on 44 different plant families, 9 genera, and 67 species, 

which include Aglaonema treubii, Allium cepa, Annona muricata, A. reticulata, A. squamosa, 

Citrus aurantifolia, C. limon, C. sinensis, Guettarda speciosa, Lycopersicon esculentum,

Mangifera indica, Musa paradisiaca, Nephelium lappaceum, Plumeria acuminata, Samanea 

saman, Solanum melongena, Tectona grandis, Vigna sesquipedalis, and Zea mays. Many of these 

species are widely cultivated in the United States (USDA and NRCS, 2002). Consequently, the 

risk rating for Host Range is High.

2.6.3. Dispersal Potential

The immature stage of this species may move for a short period of time, no more than one day, 

but may disperse several yards to other plants via wind or phoresy by other insects, such as the

three ant species, Iridomyrmex humilis, Solenopsis germinata var. rufa, and Pheidole 

megacephala (Hymenoptera: Formicidae) (DAFF, 2004; Kessing and Mau, 1992). More than 

1,300 interceptions of this pest have been reported in PestID from 40 different countries. We 

rated Dispersal Potential Low.

2.6.4. Economic Impact

If D. neobrevipes enters the United States it is likely to cause yield loss to crops such as Ananas 

comosus, Citrus aurantifolia, C. limon, C. sinensis, Lycopersicum sculentum, Musa sp., and Zea 

mays, which are present at least in Florida, Louisiana, Missouri, Arkansas, Colorado, New 

Mexico, and Tennessee (USDA and NRCS, 2002). We rated Economic Impact Medium.

2.6.5. Environmental Impact

Dysmicoccus neobrevipes is found on 44 plant families. Of these, the following families contain 

species listed as threatened or endangered: Agavaceae, Annonaceae, Anacardiaceae, 

Apocynaceae, Cucurbitaceae, Liliaceae, Orchidaceae, Polygonaceae, Sterculiaceae, and 

Verbenaceae (USFWS, 2005). These families are found within the continental United States in 

areas suitable for this insect’s development. Species belonging to these families are considered to 

be threatened and endangered in the continental United States, i.e., Agave arizonica and Nolina 

brittoniana from the Agavaceae family (see Appendix B) (USFWS, 2005).

The establishment of this pest would likely lead to the implementation of chemical and biological 

control programs in order to control its populations, as well as the populations of the ants that 

protect it (examples of controls where it was introduced). The risk rating for Environmental 

Impact is High.

Table 3. Risk rating for Consequences of Introduction.

Pest Risk elements Cumulative 

Climate-Host Risk Rating

Interaction

Host

Range

Dispersal

Potential

Economic

Impact

Environmental 

Impact

Dysmicoccus 

neobrevipes

Med (2) High 

(3)

Low (1) Med (2) High (3) Medium (11)
Ver. 1 (Original) September 5, 2012 9

2.7. Likelihood of Introduction

The Likelihood of Introduction is based upon two separate components. First, we estimate the 

amount of commodity likely to be imported (Sub-Element #1). The rating for the quantity

annually imported is based on the amount reported by the country of the proposed export and is 

converted into standard units of 40-foot-long shipping containers. Second, we estimate pest 

opportunity using five biological features (Sub-Elements #2-6). Details of the rating criteria are 

explained in PPQ (2000). These ratings are summarized below (Table 4). 

2.7.1. Quantity of commodity annually imported

Currently, izote flower production in Guatemala is small-scale because, in the majority of the 

cases, this plant is grown as a live barrier against erosion (Clark et al., 1988). Izote plants are 

mainly harvested as cane for ornamental use to export to different countries (Cubías, 1992; 

Nuñez, 1994).

Although we found no specific information about the quantity of izote flowers that would be 

exported annual, both the commodity and the market suggest that the quantity would be small. 

Thus, the quantity of commodity initially exported annually is expected be Low; exports are 

unlikely to be greater than ten 40-foot-long containers per year.

2.7.2. Survival of post-harvest treatment

Many elements of post-harvest processing described above may be highly effective against 

surface feeders, including mealybugs. For example, washing and drying would likely reduce the 

presence of D. neobrevipes on flowers of izote, but no research confirms this. Since no standard 

post-harvest treatments have been described for this product, the likelihood of these pests 

surviving is High. 

2.7.3. Survive shipment

We have no information on the shipping conditions for izote from Guatemala, but D. neobrevipes

seems likely to survive the shipment period, based on the fact that live D. neobrevipes have been

intercepted more than 1,300 times on shipments of different products (PestID, 2012). The risk 

associated with this pest surviving during shipment is High.

2.7.4. Not detected at the port-of-entry

Dysmicoccus neobrevipes adults are 0.15 cm (1/17 in) in length and 0.01 cm (1/25 in) in width. 

They are brown to grayish-orange, taking a grayish appearance in combination with the waxy

exudate that covers them (Kessing and Mau, 1992). The larvae are likely to be seen as they move. 

Coloration differences between the pests and the izote flowers should facilitate their detection at 

ports-of-entry. This pest has been intercepted by inspectors (see above) on several products. The 

risk of not detecting this pest at the port-of-entry is Medium.

2.7.5. Imported or moved to an area environmentally suitable for survival

The main markets for this product are located in the southwestern United States (California and 

Texas) (Batres et al., 2001). Because the demand for the product is so specific, we do not 

anticipate that it will be sold outside of these areas. This pest requires tropical and sub-tropical 

climates and considering destination markets within the area suitable for survival, the probability

of it being moved to an area suitable for its survival is Medium(2).
Ver. 1 (Original) September 5, 2012 10

2.7.6. Come into contact with host material suitable for reproduction

Dysmicoccus neobrevipes has many hosts available for reproduction (Ben-Dov et al., 2005; 

DAFF, 2004). Despite that, the pest has a limited inherent ability to move long distances. The 

mobile stage (crawlers) move for no more than one day, and only over short distances on the 

same plant or to neighboring plants (DAFF, 2004; Kessing and Mau, 1992). Izote flower 

importations from Guatemala are expected to occur only from May to October, when izote 

budding occurs in Guatemala (MAG, 2011). The rating for the risk that D. neobrevipes will find 

host material suitable for reproduction is Low.

The likelihood that a particular pest will be introduced is reflected in the value for the 

Cumulative Risk Rating. The Cumulative Risk Rating is Medium (11 points) for Dysmicoccus 

neobrevipes (Table 4).

Table 4. Risk Rating for Likelihood of Introduction

Pest Sub-Element Cumulative 

Risk 

Ratinga

Quantity 

Imported 

Annually

Survive 

PostHarvest 

Treatment

Survive 

Shipment

Not 

Detected 

at Port of 

Entry

Moved to 

Suitable 

Habitat

Contact 

with Host 

Material

Dysmicoccus 

neobrevipes

Low (1) High (3) High (3) Med (2) Med (2) Low (1) Medium 

(12)

a Low is 6-9 points, Medium is 10-14 points, and High is 15-18 points.

2.8. Pest Risk Potential and Conclusion

Pest Risk Potential is the sum of the Consequences of Introduction and the Likelihood of 

Introduction values (Table 5). Pest Risk Potential is a baseline estimate of the risks associated 

with importation of the commodity in the absence of mitigation measures. Dysmicoccus 

neobrevipes has a Medium Pest Risk Potential.

Identification and selection of appropriate phytosanitary measures to mitigate the risk from pests 

with particular Pest Risk Potential ratings is undertaken as part of the risk management phase 

within APHIS and is not finalized in this document. The appropriate risk management strategy

for a particular pest depends on the risk posed by that pest. APHIS risk management programs 

are risk-based and dependent upon the availability of appropriate mitigation methods. 

Table 5. Pest Risk Potential

Pest Consequences of 

Introduction

Likelihood of 

Introduction

Pest Risk Potentiala

Dysmicoccus neobrevipes Medium (11) Medium (12) Medium (23)

a

Low is 11-18 points; Medium is 19-26 points and High is 27-33 points.
Ver. 1 (Original) September 5, 2012 11

3. Literature Cited

Acuña, E, and S. Rivera. 1976. Plagas y Enfermedades Identificadas durante 1976. Centro 

Nacional de Tecnología Agropecuaria -CENTA-.

AGRIS/CARIS. 2005. FAO. AGRIS Database, 1975-2003. Search terms: Yucca elephantipes and 

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4. Preparers and Reviewers

Preparers:

John Rogers, USDA APHIS PPQ-CPHST, Raleigh, North Carolina

Helena Moreno Beltran, CEF Colombia

Luis Ernesto Forero, USDA APHIS PPQ-CPHST, Bogota, Colombia

Reviewer:

Marina Zlotina, USDA APHIS PPQ-CPHST, Raleigh, North Carolina
Ver. 1 (Original) September 5, 2012 15

5. Appendices

Appendix A. Pests intercepted on Yucca guatemalensis from 1985 to 2004

(PestID, 2009).

Pest Origin Plant part affected Interceptions (no.)

Amphiacusta sp. Honduras Plant 1

Anomala sp. Honduras Plant 1

Anthostomella sp. Dominican Republic Stem 1

Anurogryllus sp. Honduras Plant 1

Bagnalliella sp. Costa Rica, Honduras Cutting, Plant 11

Batrachedra sp. Mexico Cutting 1

Cicadellidae, species of Costa Rica Cutting, Plant 4

Cladosporium sp. Costa Rica Cutting 1

Coccidae, species of Costa Rica Cutting 1

Diaprepes abbreviatus Honduras Plant 1

Discochora yuccae Costa Rica Plant 1

Dyscinetus sp. Honduras Cutting 1

Dysmicoccus neobrevipes Dominican Republic Cutting, Plant 2

Elateridae, species of Honduras Cutting 1

Gryllidae, species of Honduras Cutting 1

Gryllus sp. Honduras Cutting, Plant 3

Hepialidae, species of Honduras Cutting 1

Heteroptera, species of Costa Rica Cutting 1

Insecta, species of Costa Rica, Honduras Cutting, Plant 5

Lepidoptera, species of Honduras Cutting 2

Luzara rufipennis Honduras Plant 1

Montezumina sp. Guatemala Leaf 1

Noctuidae, species of Costa Rica Plant 1

Orthoptera, species of Costa Rica Cutting 1

Pentatomidae, species of Honduras Cutting 1

Phlaeothripidae, species of Honduras Cutting, Plant 3

Phoma sp. Costa Rica Cutting 2

Phyllophaga sp. Honduras Cutting, Plant 2

Phyllosticta sp. Costa Rica Plant 1

Phyllosticta yuccae Costa Rica, Guatemala, 

Honduras,

Cutting, Plant 51

Prodoxus sp. Mexico Cutting, Stem 4

Scolytidae, species of Guatemala Stem 1

Scythrididae, species of Mexico Cutting 1

Tettigoniidae, species of Costa Rica, Guatemala, 

Honduras 

Cutting, Plant, Stem 8
Ver. 1 (Original) September 5, 2012 16

Appendix B. Plant species related to families of hosts of Dysmicoccus neobrevipes listed by 

the U.S. Fish and Wildlife Service considered as endangered or threatened.

AGAVACEAE

Agave arizonica 

Nolina brittoniana

ANNONACEAE

Asimina tetramera

ANACARDIACEAE

Deeringothamnus rugelii

Rhus michauxii

APOCYNACEAE

Amsonia kearneyana

Cycladenia jonesii 

Pteralyxia kauaiensis

CUCURBITACEAE

Cucurbita okeechobeensis ssp. okeechobeensis

LILIACEAE

Allium munzii

Brodiaea filifolia

Brodiaea pallida

Calochortus tiburonensis

Chlorogalum purpureum

Erythronium propullans

Fritillaria gentneri

Harperocallis flava

Helonias bullata

Lilium occidentale

Lilium pardalinum . 

Trillium persistens

Trillium reliquum

ORQUIDIACEAE

Isotria medeoloides

Spiranthes parksii

Spiranthes delitescens

Platanthera praeclara

Platanthera leucophaea

Piperia yadonii

POLYGONACEAE

Chorizanthe howellii
Ver. 1 (Original) September 5, 2012 17

Chorizanthe orcuttiana

Chorizanthe pungens var. hartwegiana

Chorizanthe pungens var. pungens

Chorizanthe robusta (incl. vars. robusta and hartwegii)

Chorizanthe valida

Dodecahema leptoceras

Eriogonum apricum (incl. var. prostratum)

Eriogonum gypsophilum

Eriogonum kennedyi var. austromontanum

Eriogonum longifolium var. gnaphalifolium

Eriogonum ovalifolium var. vineum

Eriogonum ovalifolium var. williamsiae

Eriogonum pelinophilum

Oxytheca parishii var. goodmaniana

Polygonella basiramia

Polygonella myriophylla

Polygonum hickmanii

STERCULIACEAE

Ayenia limitaris

Fremontodendron 

Fremontodendron californicum ssp. decumbens

Fremontodendron mexicanum

VERBENACEAE

Nesogenes rotensis

Verbena californica