RMD-07-02: Cereal Leaf Beetle (Oulema melanopus)

Issued: 2008-08-27

1st Revision: June 27, 2013 : Section 7.0 revised to reflect current status of decision


This Risk Management Document (RMD) includes a summary of the findings of a pest risk assessment and records the pest risk management process for the identified issue. It is consistent with the principles, terminology and guidelines provided in the IPPC standards for pest risk analysis.

1.0 Purpose

The purpose of this document is to record a risk management decision.

2.0 Scope

This risk management decision document summarizes the Canadian Food Inspection Agency's (CFIA) decision to deregulate cereal leaf beetle (CLB) within Canada.

3.0 Background

CLB has been established in Eastern Canada since the 1960s, and in British Columbia within the Regional Districts of East and Central Kootenay since 2002. In 2005, CLB was positively identified in Alberta in both the Municipal District of Taber and the County of Lethbridge. In 2007, CLB was identified in seven additional counties/municipalities in southern Alberta.

The United States Department of Agriculture Animal and Plant Health Inspection Service (USDA-APHIS), Plant Protection and Quarantine Division (PPQ) deregulated CLB within the United States of America (USA) in the 1970's. To date, the insect has been reported in 36 states. This list of states includes five which border the provinces in western Canada in which the insect has either never been identified or where it is only locally established in regulated areas.

As part of CFIA's ongoing reassessment of CLB in Canada, the Pest Risk Assessment on this insect pest was last updated in 2006. This latest assessment confirmed what previous assessments had concluded. The probability of the introduction of CLB and the consequences that would be associated with its introduction would be minimal in areas of Canada where the insect has not been detected to date.

There are currently CLB restrictions on the importation and domestic movement of straw and hay in Canada. Directive D-02-09 Hay and Straw-Import and Domestic Movement Requirements to Prevent the Introduction and Spread of Cereal Leaf Beetle - Oulema melanopus summarizes these restrictions. Directive D-99-01 Barley, Oats, Rye, Triticale and Wheat - Phytosanitary Requirements on Import, Transhipped, In-Transit and Domestic Movement includes a comprehensive summary of all the phytosanitary restrictions governing the importation and domestic movement of hay and straw in Canada.

4.0 Pest Risk Assessment Summary

The CLB is native to Europe and parts of Asia where it occasionally causes yield losses in grains and cereals such as winter wheat, spring wheat, barley, rye and oats (Hodson 1929; Hilterhaus 1965; Papp and Mesterhazy 1996). Although this pest disperses by active flight, it is only local rather than long distance movement. Adults and larvae feed on foliage which may result in yield losses as high as 55% in spring wheat and 23% in winter wheat (Campbell et al. 1998; Papp and Mesterhazy 1996). Outbreaks which cause economic damage are known to occur every 30 to 40 years in central Europe, but these are associated with the warmer climates of southeastern Europe and southwestern parts of Asia (Papp and Mesterhazy 1996; Hilterhaus 1965). The CLB has been established in Canada for over 35 years. The risks associated with it have been characterized and estimated. Major points determining the risk are summarized below.

The CLB is native to Europe and parts of Asia. It is widespread throughout eastern Canada, parts of western Canada and much of eastern and western US.

In 2005, the CLB was found to be established in the Municipal District of Taber and the County of Lethbridge, Alberta. This represented a new incursion into a previously uninfested area. In 2002, the CLB had been found in the Regional Districts of East and Central Kootenay, British Columbia.

The likelihood of introduction through infested hay and straw movement is low because the CLB has a low probability of general association with and survival in baled hay (especially alfalfa) and straw that is promptly processed and stored. Straw compressed at 105 kg/cm2 and stored for 1 day is sufficient to kill all larvae and adults (Yokoyama and Miller 2002). Beetles may survive typical baling operations in the field, but probably will not survive after 38-42 days of storage following baling, due to desiccation (Karren and Roe 2002). Similarly, grain is considered to be only a minor potential pathway for CLB as mortality of the insect occurs quickly in storage (Morrill et al. 1990).

Factors considered in potential introduction impacts include:

The establishment potential was rated as medium because suitable climate and many diverse grasses, grains and cereals exist in much of Canada where at least one generation of CLB per year can occur. This pest has already established in most of eastern Canada and is well adapted to surviving in the Canadian environment. Although some regions of the prairies could support cereal leaf beetle populations, most of the prairie climate is too cold during winter, and too hot and dry during summer to support a serious outbreak. Seriously damaging outbreaks of this pest have not been reported in eastern Canada in over 30 years. The risk scenario for southwestern Canada (i.e. southern British Columbia and southwestern Alberta) would probably be similar.

The natural spread potential was rated as low. Beetles are known to disperse locally by active flight for about 10 to 11 miles with the aid of wind (Shade and Wilson 1964; Castro et al. 1965). Rapid spread over long distances by natural means is, therefore, unlikely.

The potential economic impact was rated as medium because economic damage in most grains and cereals ranges between 25 to 50% yield loss when control measures are not in place. Severe outbreaks are estimated to occur about every 30 to 40 years in the warmer parts of CLB's natural range. Effective biological control, such as parasitoids, coupled with adverse winter conditions and drought usually maintain populations well below economic thresholds.

The potential environmental impact was rated as negligible. The CLB is expected to have little or no impact on the environment, or health, cultural and social aspects of human life.

The combined rating for potential introduction and impact is low.

Overall risk, which is a combination of the probability of introduction and the consequence of introduction, would be low. This means that based on the biology of the pest alone, continuance of current phytosanitary measures could be reconsidered. As such, phytosanitary regulation may not be necessary.

5.0 Risk Management Considerations

5.1 Potential Loss of Market Access

Based on current export patterns, CFIA deregulation of CLB could potentially impact exporters of cereal grains to California (Table 1). Although the USDA has deregulated CLB federally within the USA, the California Department of Food and Agriculture (CDFA) continues to regulate CLB at the state level. The potential pathways regulated to prevent the introduction of CLB into California include: small grain and forage seed shipped in bulk, straw and hay, grass sod, fodder and plant litter, used harvest equipment, and cut or balled Christmas trees (Scotch Pine, Red Pine, and Austrian Pine). Special exemptions exist for many of the commodities, which permits their entry into California. These exemptions are based on the recognition that certain processing methods control CLB (e.g. field baling of hay and straw, cleaning and bagging of small grains) or that there are specific time periods when live CLB would not be associated with a commodity (i.e. small grains shipments in bulk are exempt from California's CLB import requirements if shipped during the period of February 1 to April 30). Chemical insecticide treatments may also be used to mitigate the risk of introduction. However, exporters of organic small grains would be limited in the treatment options available to them.

CFIA has consulted extensively with USDA-APHIS and CDFA to ensure that alternative certification options will exist to facilitate cereal grain exports to California, following the deregulation of CLB in Canada. Following these discussions, CDFA has agreed to allow Canadian grain during the 5 month cereal crop harvest window in Canada (July 1st - November 30), to be exported to California contingent on it being stored for a minimum of 30 days. The alternative to 30 day storage would be treatment with a insect fumigant. During the balance of the year no additional storage or treatment requirements would exist.

The following table outlines the Canadian exports of agricultural products selected in 2005 to California through areas of production. The exports are represented in monetary terms for the commodities of cereal grains, cut Christmas trees, unrooted cuttings/slips, and trees and plants (including bulbs, cut flowers, foliage, etc.).

Table 1: 2005 Selected Canadian Exports of Agricultural Products to California
Area of Production Cereal grains Cut Christmas Trees Unrooted cuttings/slips Trees and plantsTable note *** (including bulbs, cut flowers, foliage, etc.)
BC $30,000Table note ** $29,243Table note * $11,028Table note * $3,919,000.00Table note **
AB, SK, MB $7,262,000Table note ** $3,372Table note * 0Table note * $20,000.00Table note **

Table Notes

Footnote *

source-Industry Canada (strategis.gc.ca)

Return to first footnote * referrer

Footnote **

source-Statistics Canada-World Trade Atlas

Return to first footnote ** referrer

Footnote ***

trees and plants are not currently regulated by California for CLB

Return to footnote *** referrer

5.2 Potential Establishment of Cereal Leaf Beetle Populations at Levels Affecting Crop Yield

Should CLB become widely established on the prairies at levels affecting cereal crop yields, economic losses could be significant. However, should CLB introduction and establishment occur, it is expected that natural parasitoid levels would increase and reduce CLB levels below economically harmful thresholds. Losses could occur during an interim period while parasitoid levels increased. In areas within Canada where this pest has been established (i.e. Eastern Canada) for more than 30 years, CLB populations have never reached levels that have significantly affected cereal crop yields or quality. Preliminary examination of CLB larvae in Alberta, have indicated that approximately 5% of the population is already parasitized.

5.3 Removal of Domestic Movement Restrictions on Cereal Hay and Straw

Deregulation of CLB in Canada would remove the domestic CLB movement restrictions that currently exist on the movement of hay and straw within Canada. These restrictions put hay and straw exporters within CLB regulated areas at an economic disadvantage. They are required to obtain domestic movement certificates for hay moving from regulated areas to non-regulated areas. In many cases, the treatment option required (e.g. storage for 90 days) cause loss of markets. Recently, municipal government representatives from newly infested areas have indicated that these domestic movement restrictions are responsible for declining straw prices within their areas.

5.4 Decreased Costs to Exporters/Importers of Cereal Hay and Straw brought into Canada from the United States

Shipments of hay and straw from the continental USA may enter Canada if accompanied by a USDA Phytosanitary Certificate indicating that the CLB import requirements summarized in Appendix 3 of Directive D-02-09 are met. Deregulation of CLB in Canada would remove the phytosanitary requirements specific to CLB and the costs associated with meeting the CLB phytosanitary import conditions. This would be of economic benefit to both potential exporters and importers of hay and straw into Canada from the USA. Appendix 4 of Directive D-99-01 summarizes the complete hay and straw phytosanitary import requirements that exist in addition to CLB.

6.0 Risk Management Decision

The existing CLB import and domestic restrictions are restrictive to industry, difficult to enforce and of limited value in stopping the introduction and natural spread of the insect. This is highlighted in the most recent Pest Risk Assessment completed on CLB which reiterated that CLB as a pest has and will continue to have, little or no significant impact on Canadian cereal crop production.

Stakeholder comments received back following the circulation of CFIA's CLB Risk Management Discussion Document (RMD-07-02) in August 2007, were generally supportive of deregulation. Further discussions with concerned stakeholders were held during the winter of 2008 to review CFIA's proposal and address any concerns.

7.0 Current Status

The CFIA announced its intent to proceed with the deregulation CLB in Canada in August 2008.

On October 1, 2008 the CFIA discontinued enforcing the import, export and domestic movement requirements for CLB as per Schedule II of the Plant Protection Regulations. At that time directive D-02-09 was revoked and the CFIA's Automated Import Reference System (AIRS) was changed to remove any of the CLB specific import requirements that had been in place on hay and straw.

Bulk cereal grain shipments have continued to move to California, under import permits issued to Canada annually by the CDFA. Between July and November, Canadian bulk cereal grains must be stored in a minimum of 30 days prior to export to California as a measure to mitigate the risk of live insects being present in the export shipment. CFIA Operations staff work with exporters in verifying that these requirements are met on an ongoing basis during this summer and fall window.

As part of an overall regulatory review, work continues towards having CLB officially removed from Schedule II of the Plant Protection Regulations.

8.0 References

California Department of Food and Agriculture, Plant Protection and Quarantine Manual, Document 3277

Campbell, J.M., Sarazin, M.J. and Lyons, D.B. 1989. Canadian Beetles (Coleoptera) injurious to crops, ornamentals, stored products, and buildings. Agriculture Canada Research Branch Publication 1826, pp. 110-112.

Castro, T.R., Ruppel, R.F. and Gomulinski, M.S. 1965. Natural history of the cereal leaf beetle in Michigan. Quarterly Bulletin of the Michigan Agricultural Experiment Station 47:623-653, Michigan State University, East Lansing.

Directive D-02-09, Hay and Straw - Import and Domestic Movement Requirements to Prevent the Introduction and Spread of Cereal Leaf Beetle (Oulema melanopus).

Hilterhaus, V. 1965.Biologisch-ökologische Untersuchungen an Blattkäfern der Gattungen Lema und Gastroidea (Chrysomelidae, Col.). (Ein Beitrag zur Agrarökologie). Z. Angew. Zool. 52:257-295.

Hodson, W.E.H. 1929. The bionomics of Lema melanopa L. (Criocerinae) in Great Britain. Bulletin of Entomological Research, 20:5-14.

Karren, J. and Roe, A.H. 2002. Third investigation and summary analyses of cereal leaf beetle mortality in alfalfa bales with a proposed decision process for export certification. Department of Biology, Utah State University, unpublished report.

Morrill et al. "Cereal Leaf Beetle, incidence at harvest and survival in storage in Montana" Journal, of Entomological Science 27(1):1-4, 1992.

Papp, M and Mesterhazy, A. 1996. Resistance of winter wheat to cereal leaf beetle (Coleoptera, Chrysomelidae) and bird cherry-oat aphid (Homoptera: Aphididae). Journal of Economic Entomology 89:1649-1657.

Plant Health Risk Assessment, Cereal Leaf Beetle: Movement with Hay and Straw, Oulema melanopus (L.) Pest Risk Assessment 1994-60 Update #2

Shade, R.E. and Wilson, M.C. 1964.Population build-up of the cereal leaf beetle and the apparent influence of wind on dispersion.Research Progress Report 98, Purdue University, Agricultural Experiment Station, Lafayette Indiana, 7 pp.

Yokoyama, Victoria "Mortality of Cereal Leaf Beetle in Compressed Hay Exports" Entomology Society of America Pacific Branch Meeting, February 19, 2005.

9.0 List of Stakeholders

  • Saskatchewan Agriculture Food and Rural Revitalization
  • Manitoba Agriculture, Food and Rural Initiatives
  • British Columbia Ministry of Agriculture and Lands
  • Alberta Agriculture Food and Rural Development
  • Canadian Nursery and Landscape Association
  • BC Landscape and Nursery Association
  • Alberta Organic Producers Association
  • Organic Producers Association of Manitoba
  • Saskatchewan Organic Directorate
  • Canadian Organic Growers
  • Organic Trade Association
  • Organic Agriculture Centre of Canada
  • Canadian Wheat Board
  • Western Canada Wheat Growers
  • Western Barley Growers

10.0 Communications Plan

Following the official adoption of a revised policy relating to the deregulation of cereal leaf beetle in Canada, CFIA notified USDA-APHIS and CDFA plant health colleagues and Canadian stakeholders of the changes that wouldresult from the deregulation of CLB in Canada.

11.0 Endorsement

Approved by:

Chief Plant Health Officer