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Biological Assessment for 

Importation of Bromeliads in 

Approved Growing Media from 

Denmark, Belgium, and the 

Netherlands 

July 2009 

United States 

Department 

of 

Agriculture 

Marketing 

and 

Regulatory 

Programs 

Animal and 

Plant Health 

Inspection 

Service
2

Table of Contents

Policy ................................................................................................................... 3 

Proposed Action............................................................................................................. 3 

Program Assessment ......................................................................................... 6 

References .......................................................................................................... 8 

Appendix 1. Pest Risk Assessment ............................................................... 10 
3

POLICY 

United States Department of Agriculture (USDA) Departmental Regulation, Fish and 

Wildlife Policy No. 9500-4, dated August 22, 1983, sets forth the purpose, policy, and 

responsibilities of USDA with respect to fish and wildlife. Agencies of the USDA will 

not fund or take any action that is likely to jeopardize the continued existence of 

threatened or endangered species or destroy any habitat necessary for their conservation. 

The USDA will coordinate with the Secretaries of the Department of the Interior and the 

Department of Commerce in the administration of the Endangered Species Act (ESA) 

and animal and plant quarantine laws. 

PROPOSED ACTION 

The United States Department of Agriculture (USDA), Animal and Plant Health 

Inspection Service (APHIS), Plant Protection and Quarantine (PPQ) is proposing 

to amend the regulations for the importation of plants and plant products (7 Code 

of Federal Regulations (CFR) part 319) to add bromeliads (Bromeliaceae) of the 

genera Aechmea, Cryptanthus, Guzmania, Hohenbergia, Neoregelia, Tillandsia, 

and Vriesea into the United States from Denmark, Belgium, and the Netherlands, 

to the list of plants that may be imported in approved growing media, subject to 

specified growing, inspection, and certification requirements. APHIS is 

requesting reinitiation of section 7 consultation with the U.S. Fish and Wildlife 

Service (FWS) on the programmatic consultation on importation of plants 

established in APHIS-approved growing media. A programmatic consultation 

between FWS and APHIS on importation of plants in growing media was 

completed on September 1, 2004. According to the FWS concurrence letter, 

“reinitiation of section 7 consultation on the programmatic consultation may be 

triggered when the proposed rule for a new class of plant importation is being 

submitted to the Federal Register.” 

Currently, bromeliads are imported from Denmark, Belgium, and the Netherlands 

(as well as some other European countries) into the United States as bare-root or 

unrooted cuttings. These plants are enterable subject to inspection findings at 

designated ports of entry to the United States, i.e., ports associated with facilities 

where propagative material can be examined (plant inspection stations). All 

bromeliad consignments must be accompanied by a USDA permit and a 

phytosanitary certificate issued by the plant protection service of the exporting 

country. This document certifies that the plants have been inspected and found 

free of quarantine pests. 

In Denmark, Belgium, and Netherlands, bromeliads are propagated and cultivated 

exclusively as greenhouse plants. Under these conditions, bromeliads are 

generally increased by seedlings (sexual or asexual) or tissue culture. The 

majority of production of the analyzed genera is done by only four businesses, 

two in the Netherlands and two in Denmark. The market for bromeliads is 
4

dominated by the patented hybrids of Deroose Plants (propagated by in vitro

methods) and Corn. Bak B.V. (primarily propagated by seed) (Samyn and 

Thomas, 1997). 

Agricultural representatives from Denmark, Belgium, and the Netherlands 

requested that PPQ consider amending the regulations to add bromeliads 

(Bromeliaceae) of the genera Aechmea, Cryptanthus, Guzmania, Hohenbergia, 

Neoregelia, Tillandsia, and Vriesea into the United States from Belgium, 

Denmark and the Netherlands in approved growing media under the provisions of 

7 CFR § 319.37–8(e). The following taxa established in approved growing media 

are currently allowed entry to the United States: Alstroemeria, Ananas, 

Anthurium, Begonia, Gloxinia (=Sinningia), Nidularium, Peperomia, 

Polypodiophyta (=Filicales), Rhododendron from Europe, Saintpaulia, 

Phalaenopsis from Taiwan, and Buxus sinica, Ehretia microphylla, Podocarpus 

macrophyllus, Sageretia thea, Serissa foetida from China, and Schlumbergera

spp. and Rhipsalidopsis spp. from Denmark and the Netherlands (7 CFR § 

319.37–8(e)). 

The proposed action would change 7 CFR part 319 and allow importation of bromeliads 

of the genera Aechmea, Cryptanthus, Guzmania, Hohenbergia, Neoregelia, Tillandsia, 

and Vriesea from Denmark, Belgium, and the Netherlands, rooted in approved growing 

media, provided they are produced, handled, and imported in accordance with the 

requirements of 7 CFR § 319.37–8(e) and are accompanied at the time of importation by 

a phytosanitary certificate issued by the plant protection service of Denmark, Belgium, or 

the Netherlands declaring that those requirements have been met. 

The proposed actions of propagating, rearing, shipping, and importing bromeliads 

from the genera Aechmea, Cryptanthus, Guzmania, Hohenbergia, Neoregelia, 

Tillandsia, and Vriesea in approved growing media into the United States from 

Denmark, Belgium, and the Netherlands must meet the following requirements in 

7 CFR § 319.37–8(e): 

 (1) Approved growing media includes baked expanded clay pellets, coal cinder, 

coir, cork, glass wool, organic and inorganic fibers, peat, perlite, phenol 

formaldehyde, plastic particles, polyethylene, polymer stabilized starch , 

polystyrene, polyurethane, rock wool, sphagnum moss, ureaformaldehyde, 

stockosorb superabsorbent polymer, vermiculite, volcanic rock, or zeolite, or any 

combination of these media. Growing media must not have been previously used. 

 (2) Articles imported under this paragraph must be grown in compliance with a 

written agreement for enforcement of this section signed by the plant protection 

service of the exporting country and PPQ, must be developed from mother stock 

that was inspected and found free from evidence of disease and pests by a PPQ 

inspector or an inspector from the plant protection service of the exporting 

country no more than 60 days prior to the time the article is established in the 

greenhouse (except for articles developed from seeds germinated in the 

greenhouse), and must be: 
5

 (i) Grown in compliance with a written agreement between the grower and 

the plant protection organization of the exporting country, in which the grower 

agrees to comply with the provisions of this section and to allow inspectors and 

representatives of the plant protection organization of the exporting country 

access to the growing facility as necessary to monitor compliance with the 

provisions of this section; 

 (ii) Grown solely in a greenhouse in which sanitary procedures adequate 

to exclude plant pests and diseases are always employed, including cleaning and 

disinfection of floors, benches, and tools, and the application of measures to 

protect against any injurious plant diseases, injurious insect pests, and other plant 

pests. The greenhouse must be free from sand and soil and must have screening 

with openings of not more than 0.6 mm on all vents and openings except 

entryways. All entryways must be equipped with automatic closing doors; 

 (iii) Rooted and grown in an active state of foliar growth for at least 4 

consecutive months immediately prior to importation into the United States, in a 

greenhouse unit that is used solely for articles grown in compliance with this 

paragraph; 

 (iv) Grown from seeds germinated in the greenhouse unit; or descended 

from a mother plant that was grown for at least 9 months in the exporting country 

prior to importation of the descendent plants into the United States, provided that 

if the mother plant was imported into the exporting country from another country, 

it must be: 

 A. Grown for at least 12 months in the exporting country (either 

Denmark, Belgium, or the Netherlands) prior to importation of the descendent 

plants into the United States, or 

 B. Treated at the time of importation into the exporting country (either 

Denmark, Belgium, or the Netherlands) with a treatment prescribed for pests of 

that plant by the plant protection service of the exporting country and then grown 

for at least 9 months in the exporting country prior to importation of the 

descendent plants into the United States; 

 (v) Watered only with rainwater that has been boiled or pasteurized, with 

clean well water, or with potable (municipal) water; 

 (vi) Rooted and grown in approved growing media listed in 7 CFR § 

319.37–8(e)(1) on benches supported by legs and raised at least 46 cm above the 

floor; 

 (vii) Stored and packaged only in areas free of sand, soil, earth, and plant 

pests; 

 (viii) Inspected in the greenhouse and found free from evidence of plant 

pests and diseases by a PPQ inspector or an inspector of the plant protection 

service of the exporting country, no more than 30 days prior to the date of export 

to the United States. 

Preshipment treatment measures (i.e., fumigation) are not included as a condition 

of entry for bromeliads in approved growing media from Denmark, Belgium, and 

the Netherlands because the pest risk assessment (USDA, APHIS, 2009) 

(Appendix 1) did not identify any quarantine pests which required treatments in 
6

order to ensure quarantine security beyond the mitigations listed in 7 CFR § 

319.37–8(e). 

For both the current importation of bare rooted bromeliads and the proposed 

importation of bromeliads of the genera Aechmea, Cryptanthus, Guzmania, 

Hohenbergia, Neoregelia, Tillandsia, and Vriesea in approved growing media 

from Denmark, Belgium, and the Netherlands, plants may be imported into the 

United States, including its possessions and trust territories. However, no 

bromeliads will be shipped directly to a location prior to passing through a PPQ 

plant inspection station where plants will be inspected at the port of entry. Once 

consignments are cleared through a plant inspection station, bromeliads could be 

distributed to any location in the United States, including its possessions and trust 

territories. 

PROGRAM ASSESSMENT 

APHIS conducted a pest risk assessment (USDA, APHIS, 2009) (Appendix 1) to 

examine the potential plant pest risk associated with the importation of 

bromeliads of the genera Aechmea, Cryptanthus, Guzmania, Hohenbergia, 

Neoregelia, Tillandsia, and Vriesea in approved growing media from Denmark, 

Belgium, and the Netherlands. The risk assessment prepared by APHIS to 

examine this proposed action followed version 5.02 of the PPQ Guidelines 

(USDA, APHIS, 2000) and characterizes risk in terms such as high, medium, or 

low, based on supporting evidence. In addition, the methods used to initiate, 

conduct, and report the risk assessments are consistent with guidelines provided 

by the North American Plant Protection Organization and the International Plant 

Protection Convention administered by the Food and Agriculture Organization of 

the United Nations. 

Quarantine Pests that Follow the Pathway of Importation of Bromeliads in 

Approved Growing Media: In the risk assessment, only the quarantine pests that 

can reasonably be expected to follow the pathway (i.e., be included in commercial 

shipments of Aechmea, Cryptanthus, Guzmania, Hohenbergia, Neoregelia, 

Tillandsia, and Vriesea spp. plants) were further analyzed. Only one quarantine 

pest was identified, Fusarium oxysporum Schlechtend.:Fr. f. sp. aechmeae (Saut. 

& Gerlach) Gordon (Fungi Imperfecti: Hyphomycetes) (USDA, APHIS, 2009). 

Fusarium oxysporum f. sp. aechmeae, is a hyphomycetous fungus that produces 

mycelia and phialides produced from single to complex conidiophores or 

aggregated into mycelia (sporodochia). On necrotic plant parts, phialides exude 

infectious asexual spores (conidia) which are aggregated into slimy masses. 

Conidia are dispersed for short distances when water is splashed onto infected 

plants. Water droplets containing spores land on adjacent plants and initiate 

infection. The distance and direction that spores are disseminated are related to 

the volume, direction, and intensity of water that falls on the plant. Within a 
7

greenhouse, conidia may be dispersed in irrigation water (Agrios, 1997; Pirone, 

1978). For that reason, dispersal to nearby outdoor plants is likely to be more 

limited than for fungi which can continuously and directly release aerial spores 

(Agrios, 1997). 

Fusarium oxysporum f. sp. aechmeae is pathogenic on a single plant genus, 

Aechmea, within one plant family, Bromeliaceae (Farr et al., 2008). In the United 

States, Farr et al. (n.d.) reported Fusarium sp. on Aechmea spp. in Florida. 

Gordon (1965) stated that A. fasciata (Lindl.) Bak. A. bromeliifolia (Rudge) Bak.,

A. coerulescens (Reg.) Bak., A. pineliana (Brongn.) Bak., and A. tinctoria (Mart.) 

Mez. are hosts of F. oxysporum f. sp. aechmeae. However, a more recent report 

(Samyn and Thomas, 1997) stated that only A. fasciata was a host of this 

pathogen and that other species of Aechmea and other taxa of Bromeliaceae were 

resistant or non-hosts. This pathogen has only been reported in greenhouses in 

Belgium (Gordon, 1965; Rattink, 1973; Samyn and Wojdyla, 1994) and Germany 

(Farr et al., 2008; O'Donnell et al., 1998). 

Weediness of Bromeliads: Tillandsia landbecki Phil. is listed as a weed of 

unknown importance in Chile (Holm et al., 1979). Tillandsia recurvata L. and T. 

aeranthos (Loisel) L.B. Smith are weedy epiphytes of trees and bushes in 

Argentina. When present in large numbers in host trees, these species compete, 

with their hosts, for light and release a growth inhibitor causing leaf abscission 

(Claver et al., 1983; Bartoli et al., 1993). When epiphytic bromeliads are 

associated with a supporting host in poor health, the presence of epiphytes is 

typically coincidental, not causal (Schubert, 1990). However, T. recurvata is 

native to the United States and does not meet the International Plant Protection 

Convention (IPPC) definition of a quarantine pest, and T. aeranthos is also likely 

already present in the United States (Kaplan, 1999). Despite this, no reported 

distributions or evidence of harm (e.g., NRCS, 2009) were found, which likely 

indicates the plants have either not escaped, or had little or no adverse impacts 

(USDA, APHIS, 2009). Only twice have any introduced ornamental Tillandsia

spp. successfully naturalized world-wide (Pemberton and Liu, 2007). Likewise, 

Tillandsia bandensis and Hohenbergia penduliflora could be problematic, but the 

evidence of harm is weak (Randall, 2002). 

Impact of Proposed Action on Threatened and Endangered Species: APHIS 

has determined that the importation of commercial shipments of Aechmea, 

Cryptanthus, Guzmania, Hohenbergia, Neoregelia, Tillandsia, and Vriesea spp. 

plants from Belgium, Denmark, and the Netherlands will have no effect on 

federally-listed species or their habitats. There are no federally-listed species or 

candidates for listing in the plant family Bromeliaceae (U.S. Fish and Wildlife 

Service, Threatened and Endangered Species System, 

http://ecos.fws.gov/tess_public/ last accessed July 7, 2009). There are no listed 

plant species that would be susceptible to F. oxysporum f. sp. aechmeae because it 

is pathogenic to only a single plant genus, Aechmea, in the Bromeliaceae. Within 

the United States and its territories, Aechmea species occur as native plants in 
8

Puerto Rico and the Virgin Islands. However, the pathogen is effectively 

removed from the pathway and effectively precluded from establishment in the 

United States by the mitigation measures already present in the applicable 

regulations (USDA, APHIS, 2009). 

REFERENCES 

Agrios, G. N. 1997. Plant Pathology, 4th ed. Academic Press, New York. 

Bartoli, C.G., J. Beltrano, L.V. Fernandez, and D.O. Caldiz. 1993. Control of the 

epiphytic weeds Tillandsia recurvata and Tillandsia aeranthos with different herbicides. 

Forest Ecology and Management 59: 289 294. 

Claver, F.K., J.R. Alaniz, and D.O. Caldíz. 1983. Tillandsia spp. epiphytic weeds of trees 

and bushes. Forest Ecology and Management 6: 367 372. 

Farr, D. F., A.Y. Rossman, M.E. Palm, and E.B. McCray. 2006. Fungal Databases. 

United States Department of Agriculture, Agricultural Research Service, Systematic 

Mycology and Microbiology Laboratory. http://nt.ars-grin.gov/fungaldatabases/. 

(Archived at PERAL) 

Gordon, W. L. 1965. Pathogenic strains of Fusarium oxysporum. Canadian Journal of 

Botany 43: 1309-1318. 

Holm, L. G., Pancho., J. V., Herberger, J. P. and D. L. Plucknett. 1979. A Geographical 

Atlas of World Weeds. John Wiley and Sons, New York. 

NRCS. 2009. The PLANTS Database. United States Department of Agriculture, Natural 

Resources Conservation Service (NRCS), The National Plant Data Center. 

http://plants.usda.gov. (Archived at PERAL) 

O'Donnell, K., E. Cigelnik, and H.I. Nirenberg. 1998. Molecular systematics and 

phylogeography of the Gibberella fujikuroi species complex. Mycologia 90: 465-493. 

Pemberton, R., and H. Liu. 2007. Rare Naturalization of an Ornamental Tillandsia, 

Tillandsia ionantha, in Southern Florida. Selbyana, The Journal of the Marie Selby 

Botanical Gardens, 28(2): 150-153. 

Pirone, P.P. 1978. Diseases and Pests of Ornamental Plants, 5th ed. John Wiley and Sons, 

New York. 

Randall, R.P. 2002. A Global Compendium of Weeds. Missouri Botanical Garden Press, 

xxxii + 905 pp. 
9

Rattink, H. 1973. Fusarium infections in Aechmea fasciata. Mededelingen van de 

Faculteit Landbouwwetenschappen, Rijksuniversiteit Gent. 38: 1417-1425 

Samyn, G., and F. Thomas. 1997. Thirty years of bromeliad breeding at the Research 

Station of Ornamental Plant Growing (Melle, Belgium). Journal of the Bromeliad Society 

47: 120-124. 

Samyn, G. and A.T. Wojdyla. 1994. Different methods for artificial in vivo 

inoculation of young bromeliads with Fusarium oxysporum f. sp. aechmea in 

function of resistance breeding. Mededelingen van de Faculteit Landbouwkundge 

en Toegepaste Biologische Wetenschappen (Belgium) 59: 1047-1057. 

Schubert, T.S. 1990. Epiphytic bromeliads on Florida trees. Plant Pathology 

Circular No. 333,Florida Department of Agriculture and Consumer Services, 

Division of Plant Industry. 

USDA, APHIS─see United States Department of Agriculture, Animal and Plant 

Health Inspection Service. 

United States Department of Agriculture, Animal and Plant Health Inspection 

Service. 2009. Importation of Aechmea, Cryptanthus, Guzmania, Hohenbergia, 

Neoregelia, Tillandsia and Vriesea (Bromeliaceae) in Growing Media, into the 

United States from Belgium, Denmark, and the Netherlands. A Pathway-Initiated 

Risk Assessment, July 6, 2009. Rev. 004. 19 pp. 
1

Appendix 1. Pathway-Initiated Risk Assessment 

Importation of Aechmea, Cryptanthus, Guzmania, Hohenbergia, 

Neoregelia, Tillandsia and Vriesea (Bromeliaceae) in Growing 

Media, into the United States from Belgium, Denmark, and the 

Netherlands 

A Pathway-Initiated Pest Risk Assessment 

July 6, 2009 

Rev. 004 

Agency contacts: 

Gary L. Cave, Ph.D., Entomologist 

Scott C. Redlin, Ph.D., Plant Pathologist 

Plant Epidemiology and Risk Analysis Laboratory 

Center for Plant Health Science and Technology 

United States Department of Agriculture 

Animal and Plant Health Inspection Service 

Plant Protection and Quarantine 

Raleigh, North Carolina 
2

Executive Summary 

In this pathway-initiated commodity risk analysis, we examine the risks associated with the 

proposed importation of Bromeliaceae in the genera Aechmea, Cryptanthus, Guzmania, 

Hohenbergia, Neoregelia, Tillandsia, and Vriesea, in APHIS-approved growing media, from 

Belgium, Denmark, and Netherlands into the United States. We followed the analytical 

methodology described in the USDA, APHIS, PPQ Guidelines, version 5.02, which describes 

how we examine pest biology in the context of the Consequences of Introduction and Likelihood 

of Introduction, and estimate Pest Risk Potential. 

We found only one quarantine pest that can follow the pathway, Fusarium oxysporum

Schlechtend.:Fr. f. sp. aechmeae (Saut. & Gerlach) Gordon (Fungi Imperfecti: Hyphomycetes), 

from Belgium. We gave this organism a Low Pest Risk Potential. All imported propagative 

materials, however, must meet the requirements specified in 7 CFR § 319.37. 

We discuss pest risk mitigation options, and measures applied by the existing regulations on the 

importation of plants in APHIS-approved growing media (7 CFR § 319.37-8). We expect these 

mitigation measures to substantially reduce the likelihood of introduction of any quarantine pests 

that may be associated with these plants, and as such, the overall pest risk potential would be low 

because these pests are effectively removed from the pathway. 
3

Table of Contents

Executive Summary ..................................................................................................................... 2

List of Tables ............................................................................................................................... 4

List of Figures .............................................................................................................................. 4

1. Introduction .............................................................................................................................. 5

1.1. Background .......................................................................... 5 

1.2. Production Conditions ........................................................ 5 

2. Risk Assessment ...................................................................................................................... 6

2.1. Initiating Event: Proposed Action ...................................... 6 

2.2. Assessment of Weediness Potential of Aechmea, Cryptanthus, Guzmania, 

Hohenbergia, Neoregelia, Tillandsia, and Vriesea. .................. 7 

2.3. Pest Interceptions ............................................................... 7 

2.4. Pest Categorization ............................................................. 7 

2.5. Analysis of Quarantine Pests ........................................... 12 

2.6. Consequences of Introduction ......................................... 13 

2.7. Likelihood of Introduction ................................................ 15 

2.8. Conclusion: Pest Risk Potential ....................................... 16 

3. Risk Mitigation Options ......................................................................................................... 18

3.1. Approved Growing Media ................................................. 18 

3.2. Systems Approaches ........................................................ 18 

3.3. Management of “Fusariose” via Genetic Resistance ..... 20 

4. Literature Cited ...................................................................................................................... 21
4

List of Tables 

Table 1. Assessment of Weediness Potential of Aechmea, Cryptanthus, Guzmania, Hohenbergia, 

 Neoregelia, Tillandsia, and Vriesea....................................................................................3 

Table 2. Quarantine Pest Interceptions on Aechmea, Cryptanthus, Guzmania, Hohenbergia, 

 Neoregelia, Tillandsia, and Vriesea as permit cargo from Belgium, and the Netherlands, 

 1985-2008. ..........................................................................................................................4 

Table 3. Pests Associated With Aechmea, Cryptanthus, Guzmania, Hohenbergia, Neoregelia, 

 Tillandsia, and Vriesea from Belgium, Denmark, and Netherlands ...................................5 

Table 4. Quarantine Pests Associated With Aechmea, Cryptanthus, Guzmania, Hohenbergia, 

 Neoregelia, Tillandsia, and Vriesea from Belgium, Denmark, and Netherlands ...............7 

Table 5. Risk Ratings for the Consequences of Introduction .......................................................10 

Table 6. Risk Ratings for the Likelihood of Introduction .............................................................12 

Table 7. Pest Risk Potential ...........................................................................................................12 

List of Figures 

Fig. 1. Plant Hardiness Zones potentially suitable for establishment by Fusarium oxysporum 

 Schlechtend.:Fr. f. sp. aechmeae (Saut. & Gerlach) Gordon ...............................................9 
5

1. Introduction 

1.1. Background 

This pest risk analysis (PRA) was conducted by the United States Department of Agriculture, 

Animal and Plant Health Inspection Service, Plant Protection and Quarantine, Center for Plant 

Health Science and Technology, Plant Epidemiology and Risk Analysis Laboratory (USDA, 

APHIS, PPQ, CPHST, PERAL) to examine the plant pest risks associated with the importation, 

into the United States, from Belgium, Denmark, and Netherlands, of propagative nursery stock in 

the genera Aechmea, Cryptanthus, Guzmania, Hohenbergia, Neoregelia, Tillandsia and Vriesea

(Bromeliaceae), in APHIS-approved growing media. 

Authority for APHIS to regulate plant pests/plant products is derived from the Plant Protection 

Act of 2000 (7 U.S.C. § 7701-7786, 2000) and the Code of Federal Regulations, 7 CFR § 319.37 

(2008). The risk assessment methodology and rating criteria and the use of biological and 

phytosanitary terms is consistent with international guidelines, e.g., IPPC, 2001, 2004, 2005, 

2008, and current Agency guidelines (PPQ, 2000). 

1.2. Production Conditions 

1.2.1. Asexually Propagated Plants 

The Bromeliaceae family is composed of about 59 genera native to the Western Hemisphere, 

specifically tropical America (Bailey and Bailey, 1976). In Belgium, Denmark, and Netherlands, 

these plants are propagated and cultivated exclusively as greenhouse plants. Under these 

conditions, Bromeliads are generally increased by seedlings (sexual or asexual) or tissue culture. 

The majority of production of the analyzed genera is done by four businesses, two in Netherlands 

and two in Belgium. The market for bromeliads is dominated by the patented hybrids of Deroose 

Plants (propagated by in vitro methods) and Corn.Bak B.V. (primarily propagated by seed) 

(Samyn and Thomas, 1997). 

1.2.2. Bare Root Plants 

For qualification to ship ornamental plants/propagative plants to the United States, plant 

producers must adhere to the procedures listed in 7 CFR § 319.37 (2008). For bromeliads, plants 

are currently grown in APHIS-approved growing media and are subject to washing of the root 

system with clean, potable water, to remove growing media from the root system. Regulatory 

officials inspect above- and below-ground plant parts for the presence of plant pests. Plants that 

are washed free of media facilitate visual inspection and the removal of symptomatic plants from 

the pathway or rejection of infested plant lots. 

European bromeliad growers state that the APHIS requirement for washing of the roots is 

detrimental because it: 1) increases the number of plant losses, 2) limits the size of the plant to be 

exported to the United States as “young plants” (versus larger “finished plants” at or near the 

“flowering stage” generating increased revenue), and 3) results in temporary plant growth 
6

reductions. There is some concern regarding a perceived increase in pest risk because a 

combination of essentially pest free plants grown in an APHIS-approved medium allows larger 

plants to be produced. The risk associated with container grown/established plants is the 

possibility that the additional or larger plant parts, including leaves or roots, might create 

additional locations for pests to be hidden, or increase the difficulty of visual inspection. 

1.2.3. Container Grown (Established) vs. Bare Root Plants (Susceptibility to 

Reduced Growth) 

Container grown plants have established root systems because they are grown for a substantial 

period of time without root disturbance. European bromeliad growers are concerned that reduced 

growth of bare root plants, caused by the desiccation of root systems, lack of nutrients, damage 

caused by shaking out, or washing, extends the time required to produce “finished” or mature 

flowering plants. Consequently, such plants may exhibit stunted or poor growth, and reduced 

flowering. Shipping established plants in media minimizes or eliminates these growth reductions. 

1.2.4. Movement of Plants 

Because the European Union (EU) has a single market system with no border controls, 

commercial plant consignments can move from one country to another without phytosanitary 

certificates. These certificates have been replaced by the ‘plant passport’ (e.g., DAFF, 2009; 

MRAE, 2003), which similarly certifies that certain phytosanitary requirements have been met. 

Nurseries producing plants that require a plant passport are subject to registration and inspection. 

In addition to plant passport requirements, plants and plant propagating material of certain 

genera which host significant (quality) pests and diseases must be accompanied by a ‘suppliers 

document, which confirms that the material being traded is substantially free of these organisms 

(e.g., DAFF, 2009; MRAE, 2003). The suppliers document will usually contain the same 

information as the plant passport. 

In addition, plant passports can certify official control. To receive a plant passport, domestic 

consignments in the EU should be free from A2 quarantine pests, which ensure both suppression 

and containment (an A2 pest is a quarantine pest present in an area but not widely distributed 

there and being officially controlled). The plant passport can also be used to certify that the A2 

pest, if subject to other requirements, e.g. place of production freedom, has met those 

requirements. This requirement is also equivalent to that of a phytosanitary certificate. 

Supplementally, plant consignments recognized as hosts of A2 quarantine pests cannot legally be 

moved without a plant passport, and non-compliance can be subject to enforcement and penalties 

as with a phytosanitary certificate. 

2. Risk Assessment 

2.1. Initiating Event: Proposed Action 
7

This commodity-based, pathway-initiated pest risk assessment was prepared in response to a 

request from the Governments of Belgium, Denmark, and the Netherlands to change current 

regulations to allow the importations of Aechmea, Cryptanthus, Guzmania, Hohenbergia, 

Neoregelia, Tillandsia, and Vriesea (Bromeliaceae), established in seedling trays, in APHISapproved growing media, or as bare-root plants with small amounts of APHIS-approved growing 

media attached to the roots. These plants are currently permitted entry into the United States as 

bare-root plants under 7 CFR § 319.37 (2008). 

There are special concerns associated with propagative material established in growing media: 

the presence of pests or biological contaminants may not be discernable by visual inspection, 

either pre-shipment or at the port of entry, and this infeasibility of complete inspection increases 

the potential of the introduction of exotic organisms; the treatment(s) of the growing media may 

not be entirely efficacious; the continual hazard of pest infestation/re-infestation of clean plants. 

These potential risks of importing propagative materials in growing media have been addressed 

and mitigated in regulations outlined in 7 CFR § 319.37-8 (2008). 

2.2. Assessment of Weediness Potential of Aechmea, Cryptanthus, 

Guzmania, Hohenbergia, Neoregelia, Tillandsia, and Vriesea. 

We determined the potential weed threat posed by Aechmea, Cryptanthus, Guzmania, 

Hohenbergia, Neoregelia, Tillandsia and Vriesea, or the existence of a previous characterization 

of these genera as weeds, below (Table 1). The results of this weed screening for these genera 

did not prompt a pest-initiated risk assessment. 

2.3. Pest Interceptions 

We listed pests intercepted on the relevant species below (Table 2). 

2.4. Pest Categorization 

Below we list pests associated with the relevant bromeliad species from Belgium, Denmark, and 

Netherlands, whether or not they are quarantine pests, and references (Table 3). Then, for 

quarantine pests, we list information on distribution, host genus/genera, plant parts affected, the 

likelihood of following the pathway, and references (Table 4). 

Table 1. Assessment of Weediness Potential of Aechmea, Cryptanthus, Guzmania, Hohenbergia, 

Neoregelia, Tillandsia, and Vriesea from Belgium, Denmark, and Netherlands. 

Commodity: We considered Aechmea, Cryptanthus, Guzmania, Hohenbergia, Neoregelia, 

Tillandsia and Vriesea. The family Bromeliaceae contains about 46 genera of tropical and 

subtropical, terrestrial, xeromorphic pachycauls to stemless epiphytic herbs. Most are grown 

ornamentally in the home or greenhouse, or outdoors in warm areas. 

Phase 1: No species of Cryptanthus or Neoregelia have naturalized in the United States 

(NRCS, 2009). Other genera are present as follows: 

• Aechmea is represented by two Puerto Rican species
8

• Four species of Guzmania are in Puerto Rico, the Virgin Islands, and Florida

• Hohenbergia has three Puerto Rican species

• Twenty Tillandsia species are in Puerto Rico, the Virgin Islands and several southern 

states

• Vriesea is represented by three Puerto Rican species

Phase 2: Is the species listed in: 

 Yes Geographical Atlas of World Weeds (Holm et al., 1979) 

 No World's Worst Weeds (Holm et al., 1977) or World Weeds: Natural Histories

and 

Distribution (Holm et al., 1997) 

 No 1982 Report of the Technical Committee to Evaluate Noxious Weeds: Exotic 

 Weeds for Federal Noxious Weed Act (Gunn and Ritchie, 1982) 

 No Economically Important Foreign Weeds (Reed, 1977) 

 No Weed Science Society of America list (WSSA, 2006) 

 No Do any literature references indicate weediness (e.g., AGRICOLA, CAB 

 Abstracts, Biological Abstracts, AGRIS) 

Phase 3: Tillandsia landbecki Phil. is listed as a weed of unknown importance in Chile (Holm 

et al., 1979). Tillandsia recurvata L. and T. aeranthos (Loisel) L.B. Smith are weedy epiphytes 

of trees and bushes in Argentina. When present in large numbers in host trees, these species 

compete, with their hosts, for light and release a growth inhibitor causing leaf abscission 

(Claver et al., 1983; Bartoli et al., 1993). When epiphytic bromeliads are associated with a 

supporting host in poor health, the presence of epiphytes is typically coincidental, not causal 

(Schubert, 1990). However, T. recurvata is native to the U. S. and does not meet the IPPC 

definition of a quarantine pest, and T. aeranthos is also likely already present in the United 

States (Kaplan, 1999). Despite this, we found no reported distributions or evidence of harm 

(e.g., NRCS, 2009), which likely indicates the plants have either not escaped, or had little or no 

adverse impacts. Only twice have any introduced ornamental Tillandsia spp. successfully 

naturalized world-wide (Pemberton and Liu, 2007). Likewise, Tillandsia bandensis and 

Hohenbergia penduliflora could be problematic, but the evidence of harm is weak (Randall, 

2002). 

Conclusion: For all of the genera considered above, only a few species exhibited even minor 

weediness. A pest-initiated risk assessment is not necessary.

Table 2. Quarantine Pest Interceptions on Aechmea, Cryptanthus, Guzmania, Hohenbergia, Neoregelia, 

Tillandsia, and Vriesea as permit cargo (bare root plants) from Belgium (BE), and Netherlands (NL), 

1985-2008 (PestID, 2008).a 

Host Origin Pest Year Part Proximityb As Forc Interceptions (no.)

Aechmea NL Bradybaena sp. (Bradybaenidae) 1987 Leaf On Plant P 1 

NL Microsphaeropsis sp. 

(Coelomycetes)

1993 - On Leaf P 1 

Guzmania BE Phoma sp. (Coelomycetes) 1996 Leaf On Plant P 1 

BE Pyrenochaeta sp. (Coelomycetes) 1998 Leaf On Plant P 1 

BE Sminthuridae 2000 - With Plant P 2 

BE Sminthuridae 2001 - With Plant C 1 
9

NL Bryocorinae (Miridae) 2000 - On Plant P 1 

NL Insecta 1998 - On Cut 

Flower 

C 1 

NL Noctuidae 1994 - On Plant P 1 

NL Orchidophilus aterrimus

(Waterhouse) (Curculionidae)

2005 - With Plant P 1 

NL Sminthuridae 1997 Leaf With Cutting P 1 

NL Sminthuridae 2000 - With Plant P 4 

NL Sminthuridae 2001 - With Plant P 1 

NL Tortricidae 2001 - With Plant P 1 

Tillandsia NL Arion sp. (Arionidae) 2007 Leaf On Leaf C 1 

NL Cecidomyiidae 2007 Leaf On Leaf C 1 

NL Haplothrips aculeatus (F.) 

(Phlaeothripidae)

2007 Leaf On Leaf C 1 

NL Microsphaeropsis sp. 

(Coelomycetes)

1996 Leaf On Plant P 1 

Vriesea BE Microsphaeropsis sp. 

(Coelomycetes)

1994 - On Plant P 1 

BE Sminthuridae 2002 - With Cutting P 1 

NL Pseudococcidae 1990 Leaf On Plant P 1 

NL Agriotes lineatus (L.) (Elateridae) 1994 - With Plant P 1 

NL Pyrenochaeta sp. (Coelomycetes) 1994 - On Leaf P 1 

Total 27 a

 No pests were intercepted on Cryptanthus, Hohenbergia, or Neoregelia, or on any plants from 

Denmark.

b

 “On” means that the pest was intercepted on the plants; “With” means that the pest was 

intercepted as a hitchhiker associated with the crates, cartons or boxes containing the bromeliads, 

not on the plants. 

c

 C = Consumption, P = Propagation 

Table 3. Pests Associated With Aechmea, Cryptanthus, Guzmania, Hohenbergia, Neoregelia, 

Tillandsia, and Vriesea from Belgium, Denmark, and Netherlands. 

Pest Quarantine Pest Reference 

INSECTA

Coleoptera: Curculionidae

Orchidophilus aterrimus

(Waterhouse)

Yes PestID, 2008 

Coleoptera: Elateridae

Agriotes lineatus (L.) Yes PestID, 2008 

Collembola: Sminthuridae

Sminthuridae sp. Yes PestID, 2008 

Hemiptera: Aclerdidae 
10

Pest Quarantine Pest Reference 

Aclerda tillandsiae Howell No Ben-Dov et al., 2006 

Hemiptera: Coccidae 

Coccus hesperidum L. No CIE, 1972; Ben-Dov et al., 2006 

Parasaissetia nigra (Nietner) No Ben-Dov et al., 2006 

Hemiptera: Diaspididae

Chrysomphalus aonidum (L.) No CIE, 1988; Dekle, 1965; Nakahara, 1982 

Diaspis boisduvalii Signoret No Ben-Dov et al., 2006 

Diaspis bromeliae (Kerner) No Ben-Dov et al., 2006 

Gymnaspis aechmeae Newstead No Ben-Dov et al., 2006 

Mycetaspis personata (Comstock) No Ben-Dov et al., 2006 

Parlatoria pergandii Comstock No Ben-Dov et al., 2006 

Pinnaspis buxi (Bouché) No Ben-Dov et al., 2006 

Hemiptera: Miridae

Bryocorinae sp. Yes PestID, 2008 

Hemiptera: Pseudococcidae

Nipaecoccus nipae (Maskell) No Ben-Dov et al., 2006 

Pseudococcidae sp. Yes PestID, 2008 

Pseudoccocus viburni (Signoret) No Ben-Dov et al., 2006 

Rhizoecus cacticans (Hambleton) No Ben-Dov, et al., 2006; Williams and Granara 

de Willink, 1992 

Lepidoptera: Noctuidae

Noctuidae sp. Yes PestID, 2008 

Lepidoptera: Tortricidae

Tortricidae sp. Yes PestID, 2008 

MOLLUSCA

Bradybaenidae

Bradybaena sp. Yes PestID, 2008 

FUNGI 

Ascomycetes 

Cochliobolus sativus (Ito & 

Kuribayashi) Drechs. ex Dastur 

[Loculoascomycetes: Dothideales]

No Crepel et al., 2006 

Fungi Imperfecti: Coelomycetes

Microsphaeropsis sp. Yes PestID, 2008 

Pyrenochaeta sp. Yes PestID, 2008 

Fungi Imperfecti: Hyphomycetes 

Fusarium moniliforme J. Sheldon No Farr et al., (n.d.); Rattink, 1973 

Fusarium oxysporum Schlectend.: 

Fr. 

No Farr et al., (n.d.); Rattink, 1973 
11

Pest Quarantine Pest Reference 

Fusarium oxysporum 

Schlechtend.:Fr. f. sp. aechmeae

(Saut. & Gerl.) Gordon 

Yes Gordon, 1965; Rattink, 1973; Samyn and 

Wojdyla, 1994 

Phoma sp. Yes PestID, 2008 

Table 4. Quarantine Pests Associated With Aechmea, Cryptanthus, Guzmania, Hohenbergia, 

Neoregelia, Tillandsia, and Vriesea from Belgium, Denmark, and Netherlands. 

Pest Geographic 

Distribution 

Host Genera Plant 

Parts 

Affected 

Follow 

Pathway 

References 

ARTHROPODS 

Coleoptera: Curculionidae 

Orchidophilus aterrimus

(Waterhouse)

Netherlands Guzmania Leaf Yes PestID, 2008 

Coleoptera: Elateridae

Agriotes lineatus (L.) Netherlands Vriesea Leaf Yes PestID, 2008 

Collembola: Sminthuridae

Sminthuridae sp. Belgium, Netherlands Guzmania, 

Vriesea

Leaf Yes PestID, 2008 

Hemiptera: Miridae 

Bryocorinae sp. Netherlands Guzmania Leaf Yes PestID, 2008 

Hemiptera: Pseudococcidae

Pseudococcidae sp. Netherlands Tillandsia Leaf, Stem Yes PestID, 2008 

Lepidoptera: Noctuidae 

Noctuidae sp. Netherlands Guzmania Leaf Yes PestID, 2008 

Lepidoptera: Tortricidae

Tortricidae sp. Netherlands Guzmania Leaf Yes PestID, 2008 

MOLLUSCA 

Bradybaenidae 

Bradybaena sp. Netherlands Aechmea Leaf Yes PestID, 2008 

FUNGI 

Fungi Imperfecti: Coelomycetes 

Microsphaeropsis sp. Belgium, Netherlands Aechmea, 

Tillandsia, Vriesea

Leaf Yes PestID, 2008 

Pyrenochaeta sp. Netherlands Vriesea Leaf Yes PestID, 2008 

Fungi Imperfecti: Hyphomycetes 

Fusarium oxysporum

Schlechtend.:Fr. f. sp. 

aechmeae (Saut. & 

Gerl.) Gordon 

Belgium Aechmea Leaf, root Yes Gordon, 1965; 

Rattink, 1973; 

Samyn and 

Wojdyla, 1994
12

Pest Geographic 

Distribution 

Host Genera Plant 

Parts 

Affected 

Follow 

Pathway 

References 

Phoma sp. Belgium Guzmania Leaf Yes PestID, 2008 

Although the taxa in Table 4 are listed as quarantine pests, we did not analyze all of them. This is 

based on a number of factors: First, incomplete identifications, which may be due to the state of 

the taxonomy or the condition or the stage of the specimen submitted for identification. Second, 

these organisms are not associated, in the scientific literature, with Aechmea, Cryptanthus, 

Guzmania, Hohenbergia, Neoregelia, Tillandsia, and Vriesea, and were intercepted, as 

biological contaminants during port-of-entry inspections, and would not be expected to be found 

with every shipment (this contamination may occur sometime during the loading procedures). 

Additionally, Aechmea spp. and other Bromeliaceae are relatively disease-resistant taxa, e.g., 

there are no species of Microsphaeropsis, Pyrenochaeta, or Phoma recorded as pathogens from 

Aechmea, Tillandsia or any other Bromeliaceae in the scientific literature (Chase, 1987). 

Although several plant pathogenic species exist within the genera Microsphaeropsis, 

Pyrenochaeta, and Phoma, many are opportunistic or saprophytic fungi (Stevens, 1974), and we 

cannot assume that the fungi intercepted on the plants were pathogenic. 

The only quarantine pest that is scientifically associated with these bromeliads, is Fusarium 

oxysporum f. sp. aechmeae (see above); this species is specific and exclusive only to Aechmea. 

Therefore, this is the only organism that will be analyzed. 

2.5. Analysis of Quarantine Pests 

The undesirable consequences that may occur from the introduction of quarantine pests are 

assessed within this section. For each quarantine pest, the Pest Risk Potential is calculated by 

summing the values for the Consequences of Introduction and the Likelihood of Introduction. 

The major sources of uncertainty present in this risk assessment are similar to those in other risk 

assessments. They include: the approach used to combine risk elements (Bier, 1999; Morgan and 

Henrion, 1990); the evaluation of risk by comparisons to lists of factors within the guidelines 

(Kaplan, 1992); the quality of the available biological information (Gallegos and Bonano, 1993); 

and the inherent, natural biological variation within a population of organisms (Morgan and 

Henrion, 1990). To address these uncertainties, the lists of factors were interpreted as illustrative 

and not exhaustive. This implies that additional biological information, even if not explicitly part 

of the criteria, can be used when it informs a rating. For each Risk Element, pests are assigned a 

rating of Low (1 point), Medium (2 points), or High (3 points). We summed the values for 

Consequences of Introduction and Likelihood of Introduction to estimate Pest Risk Potential 

(Table 7). This estimates the risks associated with this commodity. 
13

2.6. Consequences of Introduction 

In this portion of the analysis, we consider negative outcomes that may occur when the 

quarantine pest identified associated with Aechmea, Cryptanthus, Guzmania, Hohenbergia, 

Neoregelia, Tillandsia, and Vriesea, in growing media follows the importation pathway into the 

United States. 

We evaluated the potential consequences of introduction using five Risk Elements: Climate-Host 

Interaction, Host Range, Dispersal Potential, Economic Impact, and Environmental Impact. 

These reflect the biology, host range and climatic and geographic distribution of each pest, and 

are supported by biological information on the analyzed pest. We summed the values for each 

element to find the overall rating for the Consequences of Introduction (Table 5). 

Fusarium oxysporum f. sp. aechmeae 

2.6.1. Climate/Host Interaction 

Fusarium oxysporum f. sp. aechmeae has only been reported in greenhouses in Belgium (Gordon 

1965; Rattink, 1973; Samyn and Wojdyla, 1994) and Germany (Farr et al., 2008; O'Donnell et 

al., 1998). Aechmea are native to Puerto Rico and the Virgin Islands, these areas correspond only 

to U.S. Plant Hardiness Zone 11 (Fig. 1) (PERAL, 2008). Therefore, we gave a risk rating of 

Low. 
14

Fig. 1. Plant Hardiness Zones potentially suitable for establishment by Fusarium oxysporum f. 

sp. aechmeae 

2.6.2. Host Range 

Fusarium oxysporum f. sp. aechmeae is pathogenic only on Aechmea (Farr et al., 2008; Gordon, 

1965). For example, Gordon (1965) stated that A. fasciata (Lindl.) Bak., A. bromeliifolia (Rudge) 

Bak., A. coerulescens (Reg.) Bak., A. pineliana (Brongn.) Bak., and A. tinctoria (Mart.) Mez.

were hosts. However Samyn and Thomas (1997) stated that only A. fasciata was a host of this 

pathogen and that other species of Aechmea were resistant or non-hosts. This very narrow host 

range warrants a Low rating for Host Range. 

2.6.3. Dispersal Potential 

Fusarium oxysporum f. sp. aechmeae, is a hyphomycetous fungus that produces mycelia and 

phialides from single to complex conidiophores or aggregated into mycelia, sporodochia. The 

phialides exude infectious asexual spores, conidia, which are aggregated into slimy masses. 

Conidia are dispersed for short distances by water splash onto infected plants; the distance and 

direction being relative to the volume, direction and intensity of the water. For that reason, 

dispersal, inside or outside the greenhouse, is likely to be more limited than for fungi which can 

continuously and directly release aerial spores (Agrios, 1997). For these reasons, we rated the 

Dispersal Potential for this fungus Low.

2.6.4. Economic Impact 
15

Presence of leaf spots, leaf death, crown rot, and “fusariose” are noticeable disease symptoms 

which reduce the foliage quality, and therefore the value of the potted plants. The disease is 

unlikely to affect yield or have market impacts. Therefore, we rated Economic Impact as Low. 

2.6.5. Environmental Impact 

No species of Aechmea, Cryptanthus, Guzmania, Hohenbergia, Neoregelia, Tillandsia, and 

Vriesea are Federally Listed as “Threatened and Endangered” (USFWS, 2008). Because F. 

oxysporum f. sp. aechmeae is only pathogenic to Aechmea spp., its presence is unlikely to 

stimulate the need for additional chemical or biological control programs because current 

production systems already control Fusarium diseases (Agrios, 1997; Pirone, 1978). Therefore, 

we gave a risk rating of Low. 

Table 5. Risk Ratings for the Consequences of Introduction 

Pest Climate/

Host 

Host 

Range 

Dispersal 

Potential

Economic 

Impact 

Environ. 

Impact 

Cumulative 

risk ratinga 

Fusarium oxysporum f. 

sp. aechmeae

Low (1) Low (1) Low (1) Low (1) Low (1) Low (5) 

a

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

2.7. Likelihood of Introduction 

We rated the Likelihood of Introduction for a pest based on six biological factors for the pest’s 

interaction with the commodity. These areas represent a series of independent events that must 

all take place before a pest outbreak occurs, as follows: the quantity of the material imported; 

surviving post-harvest treatments; surviving normal shipping procedures; the likelihood of the 

pest not being detected at a port; the likelihood that the pest will be imported or moved into a 

suitable environment; and the likelihood that the pest will contact suitable hosts. The overall 

rating value for Likelihood of Introduction was the sum of these subelements (Table 6). 

Fusarium oxysporum f. sp. aechmeae 

2.7.1. Quantity Imported Annually 

The quantity of Aechmea spp. in growing media to be shipped from Belgium, Denmark, and 

Netherlands is unknown. However, in fiscal year 2007, 406,622 bare-root plant units and 71,220 

flasks of Aechmea were imported from Belgium and the Netherlands (APHIS, 2008b). It is 

assumed that overall less than 10 containers/ year will enter the United States. For this reason, 

we rated this element Low. 

2.7.2. Survive Postharvest Treatment 

Producers of plants in Belgium, Denmark, and Netherlands, cull infected plants and adjacent 

plants during production. After plants are selected, postharvest treatments may include the 

application of fungicidal drenches of the growing medium or foliar sprays of plants. These are 

effective controls of plant diseases caused by Fusarium spp. (Chase, 1987; Vanluchene, 1974). 

Therefore, our risk rating is Low. 
16

2.7.3. Survive Shipment 

Fusarium oxysporum f. sp. aechmeae has never been intercepted on bare root Aechmea from 

Europe (PestID, 2008). Shipments of Aechmea spp. are likely to spend only a few hours or days 

in air or maritime transit to the U. S. (Cargo Systems, 2001; APHIS, 2008a). Direct air shipments 

are expected to be the fastest mode of transport. Fusarium oxysporum f. sp. aechmeae, is highly 

likely to survive shipment because the host tissue provides a food source and protected site for 

growth (Agrios, 1997). Therefore, we rated this element High. 

2.7.4. Not Detected at Port of Entry 

Fusarium oxysporum f. sp. aechmeae may escape detection at low population levels. Careful 

inspection can generally detect infected plants, however, because symptoms (above) are readily 

visible (Rattink, 1973; Samyn and Wojdyla, 1994). Because this pathogen can be eliminated 

based on symptoms we rated this as Low. 

2.7.5. Imported or Moved To An Area Suitable for Survival 

Aechmea spp. will not grow well outdoors except in tropical or subtropical areas. Thus, the 

pathogen likely can only become established in greenhouses or in regions with tropical climates 

(Hawaii, Puerto Rico or the Virgin Islands). Plants for planting that arrive in the United States 

are distributed according to market demand. Therefore, we rated this subelement Low. 

2.7.6. Contact with Host Material 

Lack of suitable hosts restricts the opportunities for this pest to establish populations (in natural 

or greenhouse environments). Even though passive factors such as wind, water, or animals may 

aid in the dispersal of stages of pathogens, the key element is the availability of suitable hosts to 

sustain a pest population. Fusarium oxysporum f. sp. aechmeae, produces mycelia and phialides 

from single to complex conidiophores or aggregated into mycelia, sporodochia. The phialides 

exude infectious asexual spores, conidia, which are aggregated into slimy masses. Conidia are 

dispersed for short distances by water splash onto infected plants; the distance and direction 

being relative to the volume, direction and intensity of the water. For that reason, dispersal is 

likely to be more limited than for fungi which can continuously and directly release aerial spores 

(Agrios, 1997). We rated the pest Low for this subelement because (1) Aechmea spp. will be 

grown either in interiorscapes or outside only in tropical or subtropical regions, and (2) the 

pathogen has relatively limited dispersal capabilities. 

2.8. Conclusion: Pest Risk Potential 

For the single pest analyzed, Fusarium oxysporum f. sp. aechmeae, the overall Pest Risk 

Potential was Low (Table 7). 
Table 6. Risk Ratings for the Likelihood of Introduction. 

Pest Quantity 

imported 

Survive 

postharvest 

treatment 

Survive 

shipment 

Not detected 

at port-ofentry 

Moved to 

suitable 

habitat 

Contact 

host 

material 

Cumulative 

risk ratinga 

Fusarium 

oxysporum f. sp. 

aechmeae

Low (1) Low (1) High (3) Low (1) Low (1) Low (1) Low (8) 

a

 Low, 6-9 points; Medium, 10-14 points and High, 15-18 points
18

Table 7. Pest Risk Potential 

a

 Low is 11-18 points; Medium is 19-26 points; and High is 27-33 points 

3. Risk Mitigation Options 

There are special concerns associated with non-destructive inspections of propagative 

material established in growing media. For example, the presence of biological 

contaminants may not be discernable by visual inspection; and the efficacy of 

treatment(s) of the growing media may not be discernable. These risks of importing 

propagative materials in growing media have been addressed by the USDA and mitigated 

in regulations outlined in 7 CFR § 319.37-8 (2008). 

3.1. Approved Growing Media 

Growing media approved by APHIS in 7 CFR § 319.37-8 (2008) are baked expanded 

clay pellets, coal cinder, coir, cork, glass wool, organic and inorganic fibers, peat, perlite, 

phenol formaldehyde, plastic particles, polyethylene, polymer stabilized starch , 

polystyrene, polyurethane, rock wool, sphagnum moss, ureaformaldehyde, stockosorb 

superabsorbent polymer, vermiculite, volcanic rock, or zeolite, or any combination of 

these media. Growing media must not have been previously used. 

The proposed importation of Aechmea, Cryptanthus, Guzmania, Hohenbergia, 

Neoregelia, Tillandsia, and Vriesea plants in APHIS-approved growing media and under 

greenhouse growing conditions, if approved, will be managed by existing regulations (7 

CFR § 319.37-8, 2008). The mitigation measures described comprise a “Systems 

Approach” designed to establish and maintain a pest-free production environment. The 

Plant Protection Act of 2000 (7 U.S.C. § 7701-7786, 2000) defines a “Systems 

Approach” as “...a defined set of phytosanitary procedures, at least two of which have an 

independent effect in mitigating pest risk associated with the movement of commodities.” 

The IPPC defines a Systems Approach as “The integration of different risk management 

measures, at least two of which act independently, and which cumulatively achieve the 

appropriate level of protection against regulated pests” (IPPC, 2008: ISPM #5). Pest risk 

management is one of three components (analysis, management, and communication) of 

the decision-making process of reducing the risk of introduction of quarantine pests 

(IPPC, 2008: ISPM #11). These mitigations effectively remove the pests from the 

pathway prior to importation into the United States. 

3.2. Systems Approaches 

Pest Consequences 

of Introduction

Likelihood of 

Introduction 

Pest Risk Potentiala

Fusarium oxysporum f. sp. aechmeae Low (5) Low (8) Low (13) 
19

Systems Approaches are established by an importing country as an alternative to the use 

of single quarantine measures when a single phytosanitary measure is nonexistent, not 

feasible or undesirable. The combinations of specific mitigation measures that provide 

overlapping or sequential safeguards are distinctly different from single mitigation 

methodologies such as fumigation or inspection (Jang and Moffitt, 1994). Systems 

Approaches vary in complexity and are often tailored to specific commodity-pest-origin 

combinations (IPPC, 2008: ISPM #5). Options for specific measures may be selected 

from a range of pre-harvest and post-harvest measures, e.g., surveys, inspections, 

sanitation, chemical treatments, etc; and include mitigation measures to compensate for 

uncertainty. PPQ uses systems approaches for the importation of many commodities 

(e.g., tomatoes from Spain, France, Morocco, and Western Sahara; 7 CFR § 319.56-28, 

2008). These programs have performed successfully for many years as evidenced by the 

very low numbers of interceptions over the years the programs have been active. 

The three main categories of mitigation measures specifically required by 7 CFR § 

319.37-8 (e) (2008) for propagative materials are: use of pest-free propagative material, 

pest-exclusionary greenhouses and inspection. Ensuring pest-free propagative material 

requires monitoring and testing of mother stock and descendant plants (Agrios, 1997; 

Jarvis, 1992; Kahn, 1977) and the use of pest-free mother stock plants. 

The use of clean mother stock is an essential component of ornamental plant production 

(Agrios, 1997; Bodman et al., 1996; Jarvis, 1992; Jones and Benson, 2001; Metcalf and 

Metcalf, 1993; Mizell and Short, 1999). This practice excludes pests from being 

introduced into the plant production environment (Jones and Benson, 2001; Kahn and 

Mathur, 1999; Metcalf and Metcalf, 1993). 

Pest-exclusionary greenhouses employ treatments, good sanitation, e.g., surface 

disinfection of tools and plant materials, (Agrios, 1997; Barry, 1996; Bessin, 2001; 

Jarvis, 1992; Jones and Benson, 2001; Kahn and Mathur, 1999); clean water sources 

(Bodman et al., 1996; Jarvis, 1992; Kahn and Mathur, 1999; Pirone, 1978; van der Plank, 

1963); and use of approved growing media. Sanitation is the general cleanliness and 

pathogen-free condition of the nursery operation, aimed at reducing the overall inoculum 

level in the nursery (Jones and Benson, 2001). Surface disinfection may be achieved with 

isopropyl alcohol, denatured ethyl alcohol, sodium hypochlorite, and calcium 

hypochlorite. Surface disinfection of bare roots is achieved by dipping in a solution of nalkyl ammonium chloride prior to propagation. These solutions are most effective if used 

within 30 minutes of preparation (Jones and Benson, 2001). Studies on APHIS-approved 

growing media found that pathogens are not present (Santacroce, 1991). Approved 

growing media is defined in 7 CFR 319.37-8(e)(1) and 319.37-8(f)(3)(iv) (2008). 

Improper nursery practices (the primary means by which pathogens are introduced and 

spread in the nursery according to Jones and Benson, 2001) are avoided by oversight and 

quality assurance required by USDA APHIS and captured in a bilateral workplan. 

Pest management of ornamentals often includes chemical pest control (Osborne, et. al., 

2001). Chemical controls are supplemental and used in combination with other mitigation 

measures, such as pest exclusionary greenhouses (Ghidiu and Roberts, 2003; Reinert, 
20

1981). Physical pest control measures are effective mitigations in greenhouses. Such 

measures include washing with a hose and water and spraying inert soap sprays for 

aphids; spraying with horticultural oils for mealybugs, scale insects, and whiteflies; and 

physical removal and destruction for leafminers. 

Well-water is the preferred source for irrigation, since well water is generally pathogenfree, while pond water is a major source of water mold pathogens. If water must be recirculated, a bromine treatment will eradicate plant-pathogenic bacteria (Jones and 

Benson, 2001). 

The United States import restrictions barring soil carried with propagative horticultural 

plants effectively prevent the introduction of many mollusks (Robinson, 2002). Screens 

and doors exclude the entry of flying or crawling pests that cannot fit through screens 

(Bessin, 2001; Metcalf and Metcalf, 1993). The greenhouse enclosure provides a physical 

barrier to plants’ exposure to fungal spores that are rain splashed or windborne (Agrios, 

1997; Barry, 1996; Pirone, 1978). 

The mitigations detailed above emphasize the use of pest free sources of growing media 

and pest free commodity proper. There are then several mitigations aimed at ensuring that 

the pest free status is maintained throughout the production process and along the 

transportation pathway. A series of inspections are also incorporated to assure quality 

control and phytosanitary rigor. 

While not specifically required under 7 CFR § 319.37-8(e) (2008), standard industry 

practices help to further ensure that the pests of concern do not follow the pathway. These 

include sanitation and chemical treatments designed to reduce or eliminate insects 

(Bessin, 2001; Mizell and Short, 1998) and fungi (Jones and Benson, 2001), and in vitro

or aseptic vegetative propagation (Hartman et al., 2002). Other cultural practices, such as 

proper lighting, nutrition, sanitation, temperature and watering, enhance plant vigor so 

that pests are less able to infest or infect mother stock (Bodman et al., 1996; Jones and 

Benson, 2001; Kahn and Mathur, 1999). 

Because of potential phytosanitary concerns, mitigating factors for the importation of 

Bromeliads from Belgium, Denmark, and Netherlands must include those conditions 

specified in 7 CFR § 319.37-8 (2008). Concomitantly, Aechmea, Cryptanthus, Guzmania, 

Hohenbergia, Neoregelia, Tillandsia, and Vriesea must be artificially propagated and 

cannot be collected from the wild in accordance with CITES regulations (CITES, 1998). 

The use of these mitigation measures is expected to substantially reduce the Likelihood 

of Introduction, and as such, the overall pest risk potential would be rated low because 

the known pests effectively are removed from the pathway. 

3.3. Management of “Fusariose” via Genetic Resistance 

The incorporation of disease resistance is a major goal of plant breeders (Agrios, 1997; 

Briggs and Knowles, 1967; Janick, 1986; Jarvis, 1992). Bromeliad breeders have 

introduced several cultivars within Bromeliaceae, e.g., Guzmania, some of which possess 
21

disease resistance. The European Union offers attractive financial incentives for members 

of the agricultural industry to reduce pesticide use to obtain better ecological ratings 

through standards and letter grades (Redlin, 2003). Research efforts in Belgium include 

artificial inoculation for resistance breeding for this fungus taxon on Aechmea (Samyn 

and Wojdyla, 1994). Aechmea fasciata may be the most sensitive to infection by 

Fusarium oxysporum f. sp. achmeae. In Belgium, breeding for resistance to “fusariose” 

disease” is targeted at the pathogens F. oxysporum and F. moniliforme (Samyn and 

Thomas, 1997). In the Netherlands, natural genetic resistance combined with systemic 

fungicides is used to control diseases caused by F. oxysporum on 

A. fasciata (Vanluchene, 1974). 

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7 CFR § 319.37-8. 2008. U.S. Code of Federal Regulations, Title 7, Part 319.37-8 (7 

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7 CFR § 319.56-28. 2008. U.S. Code of Federal Regulations, Title 7, Part 319.56-28 (7 

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