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FORM NOCR

Application for approval to

IMPORT FOR RELEASE OR RELEASE FROM CONTAINMENT WITH CONTROLS ANY NEW ORGANISM

under section 38A of the Hazardous Substances and New Organisms Act 1996

Application Title: Release from containment of Aceria genistae, Agonopterix assimilella and Gonioctena olivacea, three biological control agents for broom

Applicant Organisation: Canterbury Broom Group

ERMA Office use only

Application Code: Formally received:____/____/____

ERMA NZ Contact: Initial Fee Paid: $

Application Status:

20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

ER-AF-NOCR-1 11/03 Application for approval to import for release or release FORM NOCR from containment with controls any new organism under section 38A of the Hazardous Substances and New Page 1 Organisms Act 1996

IMPORTANT

1. Please refer to the associated User Guide when completing this form. If you need further guidance please contact ERMA New Zealand.

2. This application form covers import for release, or release from containment, with controls, of any new organism (including a genetically modified organism) under s38A of the HSNO Act and may be used to seek approvals for more than one organism where the organisms are of a similar nature.

3. If you are making an application to import for release or release from containment any new organism (i.e. full release without controls as opposed to conditional release) you should use Form NOR. If you are making an application for a field test in containment of any new organism you should use Form NO4.

4. You should periodically check with ERMA New Zealand or on the ERMA New Zealand web site for new versions of this and any other forms mentioned. 5. You can talk to an Applications Advisor at ERMA New Zealand who can help you scope and prepare your application. We need all relevant information early on in the application process. Quality information up front will speed up the process and help reduce costs. 6. Any extra material that does not fit in the application form must be clearly labelled, cross-referenced, and included as appendices to the application form.

7. Commercially sensitive information must be collated in a separate appendix. You need to justify why you consider the material commercially sensitive, and make sure it is clearly labelled as such.

8. Applicants must sign the form and enclose the correct application fee (plus GST). The initial application fee can be found in our published Schedule of Fees and Charges. Please check with ERMA New Zealand staff or the ERMA New Zealand website for the latest schedule of fees. We are unable to process applications that do not contain the correct application fee.

9. Unless otherwise indicated, all sections of this form must be completed for the application to be progressed.

10. Please provide an electronic version of the completed application form, as well as sending a signed hard copy. 11. Note: Applications to conditionally release new organisms shall be publicly notified by the Authority (s 53(1)(d) of the HSNO Act) and may go to a hearing (s 60 of the HSNO Act).

You can get more information by contacting us. One of our staff members will be able to help you. ERMA New Zealand 20 Customhouse Quay PO Box 131 Wellington, NEW ZEALAND Telephone: 64-4-916 2426 Facsimile: 64-4-914-0433 E-mail: [email protected] www.ermanz.govt.nz

20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

Section One – Applicant Details

1.1 Name and postal address in New Zealand of the organisation or individual making the application

Name Canterbury Broom Group

Postal Address „Leslie Hills‟ RD Waiau 8275 North Canterbury

Physical Address

Phone (03) 315 8042

Fax (03) 315 8042

E-mail [email protected]

1.2 If application is made by an organisation, provide the name and contact details of a key contact person at that organisation This person should have sufficient knowledge to respond to queries and have the authority to make decisions that relate to processing of the application.

Name David Rutherford

Position Chairman, Canterbury Broom Group (CBG)

Address „Leslie Hills‟ RD Waiau 8275 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

North Canterbury

Phone (03) 315 8042

Fax (03) 315 8042

E-mail [email protected]

Alternative contact Name Richard Hill

Position Author of the application

Address Richard Hill & Associates Ltd Private Bag 4704, CHRISTCHURCH

Phone (03) 325 6400

Fax (03) 325 2074

E-mail [email protected]

1.3 If the applicant is an organisation or individual situated overseas, provide the name and contact details of the agent authorised to transact the applicant’s affairs in relation to the application This person should have sufficient knowledge to respond to queries and have the authority to make decisions that relate to processing of the application.

Not applicable

20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

Section Two – Purpose of the Application This form is to be used for an application to import for release or release from containment, with controls, any new organism (i.e. conditional release).

2.1 Give a short summary statement of the purpose of this application (to be used on ERMA New Zealand’s public register) - Maximum of 255 characters (including spaces) Briefly describe the organism(s) to be imported for conditional release or conditionally released from containment and the purpose(s) for which you wish to do so.

Approval is sought by the Canterbury Broom Group to conditionally release from containment a mite, Aceria genistae (Eriophyidae), and two insects, Agonopterix assimilella (Lepidoptera, Oecophoridae) and Gonioctena olivacea (Coleoptera, Chrysomelidae), for biological control of the weed broom.

20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

2.2 Provide a brief description of the background and aims of the project suitable for lay readers Describe in less than one page the rationale for the overall project these organisms are to be used in so that people not directly connected with the programme can understand why these organisms are being conditionally released.

Scotch broom (Cytisus scoparius) began spreading in the 1950s, and occupies more land year by year. It can invade disturbed or open ground in most habitats, forming dense stands, and shading out vegetation beneath it. This is creating increasing problems for the farming and forestry industries, and also for the conservation estate. Broom stands take land out of grazing. Fast-growing broom plants compete strongly for light and water with developing trees in pine plantations. Broom colonises gravels in riverbeds, ruining the nesting habitat of rare birds such as wrybills and creating shelter for their predators. Broom can spread into subalpine areas because it tolerates cold temperatures. It grows taller than the native subalpine flora, and can shade out these plants. Broom is a grave risk to subalpine and other ecosystems nationwide. It also threatens to become the dominant plant species in many recently retired high country pastures. Maintaining conservation values in the face of broom invasion is costly for the Department of Conservation.

In a recent nationwide survey, farmers and others noted resurgence in the importance of woody weeds in hill country pastures. Broom is barely present in many parts of the country, and yet almost half of the respondents listed it amongst their top three most serious woody weeds. It was considered to be increasing in importance by 15% of respondents. Apart from farmers and broom imposes heavy control costs on other land managers such as Territorial Authorities who must control it in order to maintain access and visibility, reduce fire risk, minimise spread to neighbours etc.

Broom grows in too many inaccessible places (often mixed with desirable vegetation) and is too widespread for conventional control methods such as herbicide application alone to be affordable or feasible. Biological control provides a complementary approach because control agents can distribute themselves wherever broom grows, and can maintain their populations from year to year. If successful, it would slow the spread of broom, and reduce the abundance and size of broom bushes. Development of a biological control solution has been in progress for many years, and three control agents are already causing significant damage to broom at times. Introducing these three new organisms is the next step in building a suite of control agents to provide maximum impact on broom.

The Canterbury Broom Group comprises farmers, forestry companies, and other land managers in Canterbury for whom broom is a major problem. The Group seeks to import three biological control agents for broom: the broom gall mite (Aceria genistae), the broom moth (Agonopterix assimilella) which feeds on foliage, and the broom leaf beetle (Gonioctena olivacea). These species come from Europe. For over ten years extensive tests have been carried out to assess whether these species would attack desirable plant species if released in New Zealand. There is no evidence that any of the three will attack any native plant, and the mite will only attack broom. There is evidence that the beetle and the moth might attack plants closely related to broom, including tree lucerne (or tagasaste; Chamaecytisus palmensis), but not necessarily at levels detrimental to those plants. The consequences of this possible non-target attack have been assessed. If these plants were attacked, the benefits of broom control achieved by introducing the agents are considered to outweigh the costs associated with non-target damage.

20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

Broom is a problem in many parts of the world, but these species have not been used before for biological control. As with any biological control project, whether these species will provide adequate control of broom is uncertain. Nevertheless, cost/benefit analysis shows that proceeding with the introductions is justified.

Section Three – Information on the Organism(s) to be Conditionally Released If more than one type of organism is to be conditionally released, this section must be completed separately for each organism.

3.1 State the taxonomic level at which the organism(s) to be conditionally released are to be specified If the taxonomic level is different to “species”, provide reasons for this. The reasons should take account of the need to adequately describe risk.

All three organisms will be designated at the species level.

3.2 Give the unequivocal identification of the organism(s) to be conditionally released Please include details on the following:

Species 1.

Latin binomial, including full taxonomic authority: (e.g. ----- Linnaeus 1753) class, order and family: Class: Arachnida Order: Acari Family: Eriophyidae Genus: Aceria Species: genistae (Nalepa, 1892). (= Phytoptus genistae = Eriophyes genistae)

Common name(s), if any:

Broom gall mite

Type of organism (e.g. bacterium, virus, fungus, plant, animal, animal cell):

Mite

20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

Strain(s) and genotype(s), if relevant:

Wild type sourced from galls on Cytisus scoparius collected near Mandagout, France

Other information (including presence of any inseparable or associated organisms and information on consideration of the organism(s) by other states, countries or organisations):

Application to release Aceria genistae in Australia was granted in 2002. The petition for release can be found in Appendix C. At November 2005 this species had not yet been released in Australia.

Species 2.

Latin binomial, including full taxonomic authority: (e.g. ----- Linnaeus 1753) class, order and family: Class: Insecta Order: Lepidoptera Family: Oecophoridae Genus: Agonopterix Species: assimilella (Treitshcke, 1832).

Common name(s), if any:

Broom shoot moth

Type of organism (e.g. bacterium, virus, fungus, plant, animal, animal cell):

Insect (moth)

Strain(s) and genotype(s), if relevant:

Wild type sourced from the United Kingdom

Other information (including presence of any inseparable or associated organisms and information on consideration of the organism(s) by other states, countries or organisations):

This species has not been considered for biological control of broom in any other jurisdiction.

Species 3.

Latin binomial, including full taxonomic authority: (e.g. ----- Linnaeus 1753) class, order and family: Class: Insecta Order: Coleoptera 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

Family: Chrysomelidae Genus: Gonioctena Subgenus: Spartiophila Species: olivacea (Forster 1771).

Common name(s), if any:

Broom leaf beetle

Type of organism (e.g. bacterium, virus, fungus, plant, animal, animal cell):

Insect (beetle)

Strain(s) and genotype(s), if relevant:

Wild type sourced from the United Kingdom

Other information (including presence of any inseparable or associated organisms and information on consideration of the organism(s) by other states, countries or organisations):

An application for permission to release Gonioctena olivacea into New Zealand under the Animals Act 1967 was submitted to MAF Regulatory Authority (Syrett et al. 1997). Permission was refused on 16 February 1998, and in its decision the Authority stated: There is evidence that the harm it could do to non-target species would be unwanted There is insufficient information to assess the relative harmful and beneficial effects of the proposed introduction.

Further evidence has been obtained since 1998, and these issues have been re-evaluated for the current application. A detailed cost-benefit analysis has been completed (Appendix B).

3.3 Provide unique name(s) for the new organism(s) to be conditionally released

Broom gall mite, Aceria genistae (Nalepa), (Acari, Eriophyidae) Broom shoot moth, Agonopterix assimilella (Treitschke) (Lepidoptera, Oecophoridae) Broom leaf beetle, Gonioctena olivacea (Forster) (Coleoptera, Chrysomelidae)

The Aceria genistae used in host range tests were collected from natural infestations of Cytisus scoparius at or near Mandagout (44º 01' N 3º 38'E), near Montpellier, France. If permission to release is granted, the A. genistae introduced to New Zealand will be sourced only from this locality. 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

Specimens of all three species will be lodged with the National Arthropod Collection, Landcare Research, Auckland, and with the MAF Reference Collection, Lincoln. Specimens will be submitted to Dr Zhi-Qiang Zhang, Dr R. Hoare, and Dr R. Leschen of Landcare Research to confirm identification before release.

3.4 Characteristics of the organism(s) to be conditionally released Provide information on the biology, ecology and the main features or essential characteristics of (each) of the organism(s) to be conditionally released. You should also indicate whether the organism is pathogenic or a potential pest or weed.

Aceria genistae (Nalepa)

Aceria genistae galls on broom

20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

Eriophyid mite

Description and biology Aceria genistae as a taxon has been recorded on the following plant species all of which belong to the sub-tribe Genistinae of the tribe Genisteae: Cytisus scoparius (the host of the type specimen from Lorraine, France), C. purgans, Ulex europaeus, U. parviflorus, Genista pilosa, G. cinerea, G. corsica, G. tinctoria and Spartium junceum.

Aceria genistae is already present in New Zealand, where it can be found under the leaflets of developing vegetative buds of gorse. It does not form a gall (Manson 1989). In New Zealand Aceria genistae does not appear to attack broom plants even when it grows together with gorse (H. Gourlay pers. comm.).

Recent research indicates that the species „A. genistae‟ is a number of distinct, monospecific types. The type found in galls on Cytisus scoparius is considered to be restricted to Cytisus and Genista, and the type found on Spartium is now considered a separate species, Aceria spartii (Castagnoli 1978). The mites identified from Ulex europaeus in New Zealand by Manson (1989) as A. genistae is almost certainly specific to this host. Aceria genistae from broom should therefore be considered a new organism under the HSNO Act. In Europe, host specific populations remain so, even in the presence of related potential hosts and their own mites. This suggests that these populations are reproductively isolated, and it is unlikely that introduced mites would interbreed with resident Aceria genistae. The introduced A. genistae will not attack gorse.

Female Aceria genistae from gorse are 129–240 μm long, 45–54 μm wide, 39–52 μm deep, spindle-shaped, and white or cream. Males exist (Manson 1989). The same „species‟ collected from broom presumably looks similar. Naked eriophyid mites are barely visible to the naked eye, and are normally detected by their effects on the host plant rather than by direct observation.

Developmental characteristics and requirements Colonies of A. genistae overwinter at the inner base of stem buds. From spring, mite feeding causes the buds to develop into a distorted mass of miniature leaves, transforming them into irregular, rounded, pubescent, non- woody galls about 5–30 mm across. Many overlapping generations develop in galls during spring and summer.

20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

Mite populations within galls can number many thousands. The galls wither in late summer and autumn, stimulating mites to emerge and crawl into the dormant stem buds to overwinter.

Native distribution, habitat and climate requirements Western Europe

Host records Gall mites (Eriophyidae) are generally regarded as highly host specific. Some authors believe that over 95% of eryophyoid mites are restricted to a single plant genus, and of those 40% are monospecific - restricted to a single species within the genus (Cromroy (1979). Certain eriophyid species are known to feed on other plant species within the same genus and exceptions are those that attack related plant genera (including some Aceria species) or other plant families (no Aceria species).

The published literature of plant host records for Aceria species is extensive and not simply anecdotal (Briese and Cullen 2001, Lindquist et al.1996). Given the lack of distinguishing morphological features and close physical association of eriophyids to their hosts, host records form an integral part in species identification (Manson 1984, 1989).

To ensure the presence of a single form, all mites used in tests were originally reared from galls collected from Cytisus scoparius.

Impact and ecology Eriophyids can be very damaging to the plant on which they feed, creating nutrient sinks that debilitate the plants, and reduce shoot extension and reproduction. Some are well-known pests (e.g. Manson 1984). Host-specificity and high impact make eriophyids good candidates as biological control agents, and several have achieved partial to complete weed control in several biological control programmes (Cromroy 1979, Briese and Cullen 2001).

Feeding by A. genistae causes gross deformities to broom buds. By migrating and forming fresh galls on successive years‟ of broom growth, this mite causes stunting, reproductive failure, and plant death in its native range.Aceria genistae is common on Cytisus scoparius near Montpellier, and in several other areas of France, particularly where broom is growing in slightly shaded conditions. It appears to be one of the few natural enemies capable of killing plants (Hosking 1990) although in its native range A. genistae appears to be susceptible to attack by predatory mites.

It is expected that A. genistae will be one of several agents that will be required to collectively reduce vigour and seed production of broom to a level that will bring about adequate control. Aceria genistae should complement the action of the seed-feeding bruchid, Bruchidius villosus Fabricius; the shoot moth Leucoptera spartifoliella (Hübner), and the psyllid Arytainilla spartiophila (Förster), which are already established in New Zealand.

20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

Affinities with New Zealand fauna According to Manson (1984), a total of 60 eriophyine mite species are found in New Zealand, including 29 species in the genus Aceria. This total includes both introduced species, such as the citrus bud mite Aceria sheldoni, a pest of lemon trees, and the wheat curl mite Aceria tulipae, a pest of stored garlic and shallot bulbs, and several native mites. Three native Aceria species attack native Fabaceae. Aceria microphyllae Manson causes a leaf erineum on Sophora microphylla. The modes of attack of Aceria carmichaeliae Lamb, which causes stem or bud galls on Carmichaelia spp., and Aceria clianthi Lamb, which causes green „witches brooms‟ on Clianthus puniceus, are very similar to that of the broom gall mite (Martin 2003).

Aculops hilli was described from broom foliage, where it lives without forming galls. Successful biological control of broom could reduce the abundance of this native species as broom populations declined. Although broom is as yet its only known host, this is presumably a native species, and biological control would have no effect on its abundance on its native host, whatever that may be.

There are two predators associated with the native kakabeak mite Aceria clianthi (Martin 2003). The native bug Sejanus albisignatus (Hemiptera: Miridae), was observed probing and apparently feeding among the distorted leaves where the mites were present, and a commonly found (probably introduced) yellow predatory mite species, Agistemus collyerae Gonzalez (Stigmaidae) has also been observed. In Europe predatory phytoseiid mites (identified as Typhlodromus pyri, A. Sheppard, CSIRO Entomology, pers. comm.) were commonly found in Aceria genistae galls, and presumably preyed on the eriophyids. T. pyri is also present in New Zealand. Although often present in galls, the structure of galls limits the predatory effects of phytoseiid mites such as this (Zhi-Qiang Zhang, Landcare Research, pers. comm.).

Aceria genistae and A. spartiophila attack the same developmental stage of broom (i.e. buds in spring) in France, but immature psyllids are often found within the galls of A. genistae, where they can develop, protected from predation. Interaction with exotic organisms that broom in New Zealand is discussed in Appendix B.

20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

Agonopterix assimilella (Treitschke)

Image from ukmoths.org.uk/show.php?bf=702 (Photo © Ian F. Smith ) Description and biology Adult: Wingspan 15–21 mm. Head and body buff; antenna shining grey to brown. Forewing buff, suffused brown and stippled with black and brownish scales except at base; hindwing whitish. Larva: Head, prothoracic plate and thoracic legs black. Body dark brown or dull dark greyish green; pinnacula black; anal plate same colour as the body (Harper et al. 2002).

Developmental characteristics and requirements Larvae emerge in autumn in Europe and hibernate in the stem, while still small, covering the entrance hole with silk. In February larvae re-emerge and, depending on altitude, feed until March or early May (Harper et al. 2002; Paynter & Jourdan 1998), living between two twigs spun together at a joint. Pupation occurs in the soil. Adults emerge during April-June (Harper et al. 2002). Adults are long-lived and aestivate for several weeks (Paynter & Jourdan 1998), prior to oviposition, which occurs until September (Emmet 1988).

Native distribution, habitat and climate requirements Agonopterix assimilella occurs commonly throughout England, Wales, Ireland and Scotland to Orkney. It is also found throughout Europe, including Scandinavia, to Russia and Asia Minor (Harper et al. 2002), although it is apparently restricted to higher altitudes (>500 m a.s.l.) in the southern part of its range. For example, in the Parc National de Cévennes, it is abundant between 800 and 1250 m a.s.l. (Q. Paynter, pers. obs.) and all broom plants growing at a field site at L‟Esperou, Gard, France (44º 05‟N, 3º 33‟E; 1200 m a.s.l.) were infested with A. assimilella larvae (Paynter & Jourdan. 1998).

Establishment and dispersal Agonopterix assimilella is widespread and occasionally abundant throughout Western Europe. This wide distribution across a range of climatic types suggests that this species could establish wherever broom occurs in 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

New Zealand. However, the restriction of moths to higher-altitude sites in southern Europe indicates A. assimilella may perform best at colder, higher altitude sites in New Zealand.

Host records Cytisus scoparius (Scotch broom) is recognised as the main host plant of A. assimilella (Harper et al. 2002). Shaw & Fowler (1996) recorded larval ties on C. striatus, and C. multiflorus. Lvovsky (1981) also mentions greenweed (Genista) as a host plant. Paynter & Jourdan (1998) reared two larvae collected from 10 Genista pilosa plants at L‟Esperou, France, where three bushy shrub species that belong to the tribe Genisteae (Scotch broom, G. pilosa and Cytisus purgans) grow in mixed stands. However, the abundance of larvae on G. pilosa was 27 times lower than on Scotch broom, and no larvae were found on any Cytisus purgans plant growing nearby.

Impact and ecology The larva is the damaging stage, feeding on broom foliage and green stems, sometimes ring-barking and killing small twigs and branches (Q. Paynter, pers. obs.). A. assimilella is one of the most common insect species occurring on broom in Europe.

Affinities with New Zealand fauna The family Oecophoridae is well-represented in the New Zealand fauna. Dugdale (1988) records 32 genera within the family. Few host–plant associations are recorded, but none of these hosts are legumes (Dugdale 1988). There are no native Agonopterix species, and there is no possibility that A. assimilella will interbreed with native species. A. umbellana has been introduced to attack gorse. There is no evidence that A. assimilella interbreeds with A. ulicetella in Europe.

Defoliation by A. assimilella will significant complement the activity of the three broom-feeding species already present in New Zealand: Bruchidius villosus (feeding on seeds), Leucoptera spartifoliella (mining green stems), Arytainilla spartiophila (sap-sucking), and also of Gonioctena olivacea, which is mainly active later in the year, after A. assimilella larvae have completed development (see Appendix B).

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Gonioctena olivacea (Forster)

from http://homepages.ulb.ac.be/~pmarduly

Description and biology Adult beetles exhibit marked sexual dimorphism in both size and colour, although there is substantial variation within each group. Males are 2.6–4.1 mm long (mean 3.6 mm), females 3.9–5.0 mm (mean 4.3 mm) (Waloff & Richards 1958). Females can usually be distinguished from males by their larger size, but the sexes can also be separated by the shape of their maxillary palps in which the last segment is broad and securiform in the male but only slightly expanded in the female. Females fall into two main colour forms. The first may be entirely yellow- brown, greyish-brown, or pure brown, except for a black suture of the elytra. Only the newly emerged, young females of the autumn generation lack the black suture. Black pigmentation develops gradually, and may also occur on the head and the prothorax. In the second form, brownish females may have, besides the suture, two black lateral lines on the elytra, with a variable amount of black pigmentation of the head and thorax. The brown colouration on the males may merge into brick-red or even bright red.

Ovoid yellow eggs are laid on the leaf surface and measure around 1 mm in length. Larvae resemble small brown crocodiles. There are 4 larval instars, the largest measuring 5 mm. Larvae feed grossly on leaves and young shoot tips in late spring and early summer. Larvae pupate in the leaf litter.

Developmental characteristics, and ecology Adult beetles are long-lived, and may survive for three seasons. Beetles hibernate in the soil or litter layer under broom bushes during winter and emerge from April onwards in the Northern Hemisphere (Waloff & Richards 1958). Emergence peaks in May, and tails off in June. Since adult emergence is protracted, oviposition also spans a wide period, from the middle of May to the middle of August. This means that all developmental stages can occur simultaneously. Adult beetles mate immediately after they emerge. They feed on broom leaves, and female beetles lay eggs mainly on the upper surfaces of the leaves. On completion of egg-laying (86–112 days), beetles return to the soil to overwinter, where 20–33% survive to lay again in the following summer. Eggs take about 18 days to hatch. Each of the four larval stages also feeds on broom leaves. Fully-fed fourth instar larvae pupate in the soil, giving rise to a new generation of adults that emerge between August and October. There is a large fauna of predaceous insects that feed on larvae in the UK. The total loss of progeny to predation over two years was 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

78% and 92% (Waloff & Richards 1958). Similar predators are rare or absent in New Zealand (Syrett 1993), and populations are likely to be larger here than in the UK. From the middle of June until the end of August adults of the first generation gradually descend back into the soil where they die, or hibernate for a second season. New adults feed on the plants for only one or two weeks before entering the soil with large fat-bodies, but still sexually immature, to hibernate for the winter. The same adults may appear in three successive years, reproducing in years two and three. The average number of eggs laid by a single female over two seasons was 250–320 (Waloff & Richards 1958, Richards & Waloff 1962).

Native distribution, habitat and climate requirements The distribution of Gonioctena olivacea includes most of Europe, with unconfirmed records from Algeria. It occurs commonly throughout the UK, in Sweden, Finland, Denmark, the Netherlands, Spain, Gibraltar, Portugal, France, Germany, Switzerland, Austria, Italy, Sicily, Poland, Czechoslovakia, Hungary, and Greece, but is absent from the USSR (Waloff & Richards 1958).

Establishment and dispersal In Europe G. olivacea is common and widespread. Areas in New Zealand where broom occurs can all be climatically matched to areas in Europe where G. olivacea occurs naturally, indicating that G. olivacea would adapt to conditions throughout the areas occupied by broom in New Zealand.

Host records Cytisus scoparius (broom) is widely recognised as the main host plant of G. olivacea. However, there are records in the literature of G. olivacea collected from Cytisus purgans, C. multiflorus (white broom), C. striatus (Portuguese broom), Genista cinerea, G. florida and Lupinus arboreus (tree lupin). Waloff & Richards (1958) could not rear G. olivacea on Ulex europaeus, Trifolium repens, or Laburnum sp. In a field study aimed at measuring the natural host range of beetles feeding on broom in SW Europe, G. olivacea was shown to clearly favour Cytisus spp. over Genista spp. and Spartium junceum (Spanish broom) (Syrett & Emberson 1997). Gonioctena olivacea was the second most commonly collected species in this study: 84 specimens were collected from five Cytisus species, but none from two species of Genista or from one species each of Chamaespartium, Adenocarpus, Retama, and Spartium, which also belong to the Genisteae.

Impact and ecology Adults emerge in the spring after overwintering in the litter under broom bushes and feed on broom leaves. Eggs are laid there, and hatching larvae continue to feed on leaves. Larvae are sufficiently mobile to move to and feed on the growing points and fleshy green stems. Heavy feeding reduces photosynthetic area and destroys the growing stem, reducing the rate at which broom grows.

Affinities with New Zealand fauna In Europe eggs and larvae of Gonioctena olivacea suffer very high levels of mortality from attack by generalist predators, in particular by mirid bugs (Richards & Waloff 1962). The European predatory species implicated are 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

not present in New Zealand, and other mirid species are not commonly found on broom here (Syrett 1993). Pupae lying in the top layer of litter under broom bushes are vulnerable to predation by specialist ecto-parasitic ground beetles (Carabidae). In Europe this is a significant mortality factor, probably accounting for 20% of the population (Richards and Waloff 1962). New Zealand does not have these specialised carabid ecto-parasitoids, and the dominant pterostichine predators occurring here are generally forest-inhabiting species, less well adapted to open habitats such as those occupied by broom. This might result in higher equilibrium populations of G. olivacea occurring in New Zealand than are found in Europe.

Interaction of proposed agents with other species attacking broom in New Zealand The exotic and indigenous insect fauna associated with broom in New Zealand was surveyed by Syrett (1993). Interactions between the proposed agents and resident insects are discussed in section 6.1 and in Appendix B. There are no native Gonioctena species, and there is no possibility that G. olivacea would interbreed with native beetles.

Interactions of agents with other broom insects The proposal to introduce these species forms part of a concerted effort to introduce a range of biologically and ecologically compatible biological control agents that work additively, and possibly synergistically, to reduce the vigour and population density of broom in New Zealand. Further agents may be introduced as part of this plan. The programme is designed to minimise negative interactions between agents, and so maximise the overall effect. This is achieved by selecting agents that act on different plant structures, or at different times of the year on the same part of the plant. Selection takes into account the role played by resident natural enemies, whether native or self-introduced. There is strong evidence that biological control of broom in New Zealand is feasible (Appendix B).

3.5 If the organism to be conditionally released is a genetically modified organism, where applicable provide details on the development of the organism If the organism to be conditionally released is a genetically modified organism, state whether the development of the organism was carried out under a HSNO approval. If this was the case, provide the approval number and translate the relevant details to the headings below. If the genetically modified organism is to be imported for conditional release, also provide this information to the extent possible:

Identify the category of the host organism (i.e. category 1 or 2) and genetic modification (i.e. category A or B) involved in the development of the organism with reference to the HSNO (Low-Risk Genetic Modification) Regulations 2003. Please explain your characterisation.

Aceria genistae to be introduced have not been genetically modified. Agonopterix assimilella to be introduced have not been genetically modified. Gonioctena olivacea to be introduced have not been genetically modified. 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

Vector system(s) used in the development of the genetically modified organism(s).

Not applicable

Type and source of additional genetic material

Not applicable

Use of special genetic material (please complete this table by marking the correct box):

Yes No Were native or valued flora or fauna used as the host organism(s)? Was genetic material from native or valued flora and fauna used? If native flora and fauna were involved, were the species concerned indigenous to New Zealand? Was human genetic material involved? Answer Yes if human genetic material in any form was used, i.e. obtained directly from humans (either Māori or non- Māori from a gene bank, synthesised, copied and so on). Was genetic material obtained directly from human beings used? If Yes, provide additional details below.

If the genetic modification involved DNA of human origin, provide details of from where the material was obtained (including provenance and/or informed consent), and whether approval was obtained from an Ethics Committee, and/or whether consultation with Māori has taken place.

Not applicable

Other relevant details (such as what techniques or experimental procedures were used, whether any unusual manipulations were carried out, and how the foreign genetic material is expressed).

Not applicable

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Section Four – Proposed Conditional Release Programme and Controls

4.1 Proposed Conditional Release Programme Please provide full details of your intended conditional release programme e.g. size, timing and location(s) of the conditional release etc. Specifically indicate whether or not an expiry date for any approval is expected and give reasons for this expectation.

An application to import Aceria genistae and Agonopterix assimilella into containment was approved by ERMA (approval code NOC05012).

Gonioctena olivacea has been imported repeatedly for evaluation since 1995 into the containment facility at Landcare Research, Lincoln, under the following MAF import permits: G95/INV/11 1997000250 1998003226 20030018389 2005026871.

This proposal seeks approval to remove these three agents from containment for release. In fulfilment of the MAF import permit conditions all three species will be quarantined before release to eliminate any parasitoids.

Galls of Aceria genistae will be imported from France in July 2006. As galls dry, emerging mites will be transferred individually to vegetative buds on small broom plants, and these will be grown in containment in isolation from imported material. Only this mite produces the typical galls illustrated in section 3. Once galls are mature, and once time for at least one mite generation has elapsed, a selection of galls will be dissected. The identification of the eriophyid mites will be confirmed, and permission to release from containment will be sought from MAF. Galls will then be removed briefly from containment, so that at least 100 individual mites can be transferred to new plants outside of containment. The galls will be immediately destroyed. After several months, mature galls that have developed on the new broom plants will be harvested, and tied to broom plants in at least one Canterbury site in spring 2007 so that mature mites can disperse from the drying gall and colonise vegetative buds. The number and size of releases will be determined by rearing success.

Approximately 200 overwintering larvae of Agonopterix assimilella will be collected from broom in England and shipped to containment in New Zealand in April/May 2006. Larvae will be reared to adulthood in containment. Once identification and health status have been confirmed, permission to remove pupae of the following generation from containment will be sought from MAF. Larvae being reared for host specificity tests were infected by what was assumed to be a microsporidian disease, causing high mortality (Paynter & Jourdan 1998). The impact of this disease on populations in Europe is unknown. In laboratory rearing any disease will be eliminated from populations before moths are released from containment into the New Zealand environment. Progeny of paired adults will be line-reared, and any lines that show signs of ill-health (such as increased mortality, reduced lifespan, reduced fecundity etc) or disease will be isolated and eradicated. Once released from containment, moths will be released into large cloth bags over broom bushes in at least one Canterbury site in early summer 2007. The number and size of releases will be determined by rearing success. 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

Approximately 200 Gonioctena olivacea larvae will be collected in England and shipped to New Zealand in July 2006 to complete development in containment. Progeny of paired adults will be line-reared, and any lines that show ill-health (such as increased mortality, reduced lifespan, reduced fecundity etc) or disease will be isolated and eradicated. Once identification and health status have been confirmed, permission to remove the resulting adults from containment will be sought from MAF, in accordance with import permit conditions. Approximately 20 adults will be released onto each of five sleeved broom bushes in at least one site in Canterbury. The number and size of releases will be determined by rearing success.

4.2 Proposed Course of Action if the Conditional Release Approval is Set to Expire Indicate by marking the following table which course of action is preferred if the conditional release approval is set to expire:

Course of Action Yes No

1. Full (unconditional) release of the organism. Note: you will need to formally apply for a full (unconditional) release at or after the time of applying for a conditional release but prior to its expiry. The full release would then take effect immediately after the expiry of the conditional release approval. 2. Return of the organism into containment through an existing containment approval. Note: give the appropriate approval code and relevant details in the space below. 3. Return of the organism into containment through a new (yet to be gained) approval. Note: you will need to formally apply for a containment approval at or after the time of applying for a conditional release but prior to its expiry. 4. Disposal of the organism. Note: unless you have gained another approval (containment or full unconditional release) prior to the expiry of your conditional release approval you will need to provide information relevant to disposal in section 4.3.

Please give reasons justifying the selection of the (above) course of action and any other relevant information (e.g. the approval code and details of the appropriate existing containment approval etc.)

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Not applicable. Conditions are to be set in perpetuity

4.3 Disposal of the organism(s) on the expiry of the conditional release approval Section 38F of the HSNO Act requires the organism(s) to be disposed of if and when a conditional release approval expires, unless before expiry another approval (containment or full unconditional release) is granted under the Act. Provide information (preferably in the form of proposed controls) to explain what steps will be taken to ensure that the organism(s) can be identified and located at the expiry of the approval, and the method of disposal intended.

Not applicable. Conditions are to be set in perpetuity

4.4 Proposed control(s) Please outline the relevant control(s) that you recommend be imposed to deal with any risks that may be posed by the organism(s) to be conditionally released. In doing so make reference to the types of controls listed in section 38D of the HSNO Act. If you do not consider any of these controls to be appropriate explain why. Also provide information on how effective these controls are likely to be in meeting the objective(s) of the control(s).

The applicants request that the following conditions be placed on the release of these agents:

1. Aceria genistae must be collected from typical galls on Cytisus scoparius from the Montpellier region, France

2. Agonopterix assimilella must be collected from Cytisus scoparius in England

3. Gonioctena olivacea must be collected from Cytisus scoparius in England.

A declaration of identification and source should be included with each shipment.

These conditions are sought to minimise the risk of non-target attack by ensuring that the material imported is sourced from agent populations that are contiguous with those used in host-range testing.

The controls requested apply before importation, and cannot influence the risks, costs or benefits incurred once the agents are released in New Zealand. For this reason, none of the controls listed in Section 38D of the HSNO Act are deemed appropriate, except as described in section 4.5.

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4.5 Monitoring of effects Conditional releases may provide an opportunity to collect information related to the occurrence of adverse effects and to the operation or not of associated pathways. The Authority wishes to encourage applicants to take full advantage of the conditional release situation to conduct monitoring that will provide an assurance that risks are being effectively managed through the controls imposed and/or provide information that will assist in the consideration of any future conditional- or full-release applications. Describe any such monitoring you propose to put in place.

Agents can disperse freely once released, and release implies that populations cannot be eradicated by local action.

Biological control agents often persist at such low density that detection is difficult for some years. Population build-up to the point of equilibrium density (and therefore maximum impact) also usually takes many years. It would not be valid to measure impact until equilibrium density had been achieved, and this is likely to be many years hence. Just how many years is rarely predictable. This is beyond the horizon of most funding bodies, which have limited interest in adequately funding this style of research. It is certainly beyond the present scope of the applicant.

The Canterbury Broom Group (CBG) undertakes to monitor the establishment of each species by visiting releases sites and sampling broom bushes at least four times over two years. Although this is unlikely, the agents may become abundant in this time. If so, CBG will also sample legume species growing within 100 m of the release point to search for any non-target attack. Funding for this project does not currently extend beyond June 2008, and CBG cannot commit to monitor beyond this time. Any further steps to gain funding to monitor the performance of either species will be considered only once full establishment is confirmed. Significant investment to evaluate the field effectiveness of the agents before the agents achieved maximum potential would be inefficient and counterproductive.

Section Five – Identification of Risks, Costs and Benefits Risk means the combination of the magnitude of an adverse effect and the probability of its occurrence. Cost means the value of a particular adverse effect expressed in monetary or non-monetary terms. Benefit means the value of a particular positive effect expressed in monetary or non-monetary terms. In this part of the form you are required to identify (in section 5.3) the risks, costs and benefits of the organism(s) in the context of the application. A very broad approach should be taken to this, so that a wide range of possibilities are canvassed. However, it is also important at the end of this exercise but still at the identification stage to identify those risks, costs and benefits which warrant more detailed assessment at a later stage (in section 6). To assist the process of identification this section also requires information to be provided on the ability of the organism(s) to establish a self-sustaining population and on the ease of eradication. Please refer to the ERMA New Zealand Technical 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

Guides “Identifying Risks for Applications” and “Risks, Costs and Benefits for Applications for further information. These are available from the ERMA New Zealand website or in hard copy on request.

5.1 Ability of the organism(s) to establish a self-sustaining population Discuss the ability of the organism(s) to establish a self-sustaining population and the ease with which the organism(s) could be recovered or eradicated if an undesirable self-sustaining population established.

The objective of introducing Aceria genistae, Agonopterix assimilella and Gonioctena olivacea to New Zealand is to establish self-sustaining populations on broom in Canterbury. It is assumed that the insects will eventually colonise broom populations throughout New Zealand, contributing to the suppression of broom populations and the maintenance of weed control everywhere. It is not expected that any populations will be considered undesirable because all three species pose only low risk to native plant populations, and to the integrity of native ecosystems and processes (see section 6.1), and because the economic benefits of introduction outweigh the costs of possible non-target effects on exotic woody legumes.

5.2 Effects of any inseparable organism(s) State whether or not there are any inseparable organisms associated with the organism that is the subject of the application. If there are any effects of inseparable organisms that might need to be considered, state this and then identify them under the relevant headings in section 5.3.

No inseparable organisms are known for these species.

Thirty mid-size immature stages of each species will be randomly selected from the rearing colony, smeared and submitted to Biodiscovery NZ (Dr P. Wigley) for examination for unwanted associated micro-organisms.

Associated organisms Larvae of Agonopterix assimilella being reared for host specificity tests in France were infected by what was assumed to be a microsporidian disease, causing high mortality (Paynter & Jourdan 1998). Populations of G. olivacea imported into containment in New Zealand for host specificity tests in 1997 were infected by a microsporidian disease (P. Wigley, Biodiscovery NZ, pers. comm.). The impact of these diseases on populations in Europe is unknown, but rearing methods in containment will be designed to eliminate disease from populations before moths are released into the New Zealand environment. No such diseases are known for Aceria genistae.

All species will be reared through a full generation in quarantine to isolate and eliminate any associated parasitoids or predators (H. Gourlay, pers. comm.).

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5.3 Identify all the potential risks, costs and benefits of the organism(s) to be conditionally released Please identify all potential risks, costs and benefits whether you consider them to be non-negligible or not. To do this effectively you should identify both the source of the risk (or hazard) and what is at risk (or area of impact). You should also identify the route (or exposure pathway) between the source and the area of impact. An indication of any non-monetary and monetary costs and benefits to be derived from the conditional release of the organism(s) and whether these are direct or indirect should be given. Please cover all of these issues under each of the following headings (areas of impact) which reflect those matters referred to in Part II of the HSNO Act:

A. Effects on the environment (in particular on ecosystems and their constituent parts) As per sections 5(a), 6(a) and 6(b) of the Act, list the risks, costs and benefits associated with the organism(s) to be conditionally released. Also address the ways that these risks, costs and benefits might adversely effect or improve/enhance (in the case of benefits) the New Zealand environment e.g. the life supporting capacity of air, water, soil and ecosystems; the sustainability of native and valued introduced flora and fauna; natural habitats and the intrinsic value of ecosystems; New Zealand‟s inherent genetic diversity; animal or plant health.

Risks and costs:

POTENTIAL RISK SOURCE OF RISK IMPACT AND/OR METHOD USED ASSESSMENT OF RISK AND TO: PATHWAY TO IDENTIFY ITS EFFECT RISK

Life-supporting Temporary baring of Increased water runoff Formal Very unlikely and minimal capacity of ground from rapid causes erosion brainstorm effect. Changes would be slow water, soil and death of broom and gradual air Insects attack tree insect damage makes less Consultation, See Jarvis et al.2003 lucerne effective as soil cost–benefit conservation planting analysis Alternative species Literature, cost– see Jarvis et al. 2003 requires development benefit analysis Biomass or density Reduced water quality Previous Effect insignificant - reversible, of` broom reduced through slower colonising applications rare and occasional suddenly of stream banks Less litter-fall reduces soil Formal Broom likely to be replaced by organic content brainstorm other, more desirable vegetation Net effect minimal Less protection of erosion- Previous Minimal to minor localised prone soil and stream applications effect until replacement 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

banks vegetation grew. Slow change is more likely Reduced carbon capture Formal No significant effect envisaged. brainstorm Overall broom is a relatively insignificant carbon sink Measurably less Previous Minimal to insignificant effect. photosynthesis and oxygen applications Broom is a relatively production insignificant O2 contributor

Sustainability of New insects Increased density of Formal See section 6.1 native and valued become abundant predators feeding on brainstorming, introduced flora agents alters native food previous and fauna web applications Presence of immature Formal See section 6.1 stages as prey for brainstorming, parasitoids and predators previous alters food web applications Presence of eggs as prey Formal See section 6.1 for parasitoids and brainstorming, predators alters food web previous applications Agonopterix moths Formal Possible effect, but increment in increase the incidence of brainstorming, total pool of pollinating insects pollination previous negligible, and hence effect applications minimal B1 Gonioctena larvae Extra food for common No significant rise in wasps abundant and German wasps numbers directly attributable to increases wasp problem this because larvae would be a small part of available food resource Less broom Fewer buds decreases food Consultation See section 6.1, 6.3 supply for kererū less broom decreases host Reid 1998 Negligible effect - one of many pool of native mistletoe hosts, still available in part Gaps appear in Broom replaced by other, Formal Effect likely in places, see broom stands more damaging weeds brainstorming, section 6.1, 6.4. No weeds more previous damaging applications Agents feed on non- Insect damage reduces Experiment, See section 6.1 and Appendices target native plants viability of native plant consultation, C–E populations literature Agonopterix attacks Survival and reproduction Experiment, Non-target effects expected to be several other woody reduced, populations consultation, negligible, except tree lucerne, legumes suffer literature see section 6.1 and 6.3 Ecotype that was not Unexpected non-target Previous Insignificant risk – release tested is released damage to valued plants applications population obtained from same and/or alterations to food locality as test population. webs See section 4.1 Swift evolutionary Unexpected non-target Previous Insignificant risk – rate of change in insect damage to valued plants applications change would be slow, such loss and/or alterations to food of specificity never observed in webs host-specific insects Release of associated Suppression or extinction Previous No associated organisms known, 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

organisms of valued flora and fauna applications parasitoids will be excluded in containment, see section 3.5 Agonopterix moths Competition with native Formal Insignificant risk – Adults forage feed on nectar nectar-feeding insects brainstorm little, and add little to total reduces their viability biomass of nectar-feeders

Maintenance of Broom biomass and Area of native forest Formal Effect minor as broom not native habitats populations reduced regenerating annually brainstorming currently a widespread nurse significantly reduced previous crop. See section 6.1 through reduced value as a applications nurse crop Smaller increase in plant Effect minor as broom not and animal biodiversity currently a widespread nurse from regenerating forest crop. See section 6.1 Competition with the Suppression of control Formal Not expected, additive effects control agent, broom agent leads to less control brainstorming expected, see Appendix B psyllid of broom nationwide Intrinsic value of Less broom in the Less pollen available to Literature, See sections 6.1, 6.4 ecosystems environment honey bees, hence less consultation, pollination previous applications Fewer native insects Formal See section 6.1 because less broom to use brainstorming Increased plant and animal Formal See section 6.1, also a potential biodiversity in and on brainstorming benefit replacement vegetation Fewer native bees because Formal Not expected as broom is not pollen source reduced brainstorming currently seen as a significant source of pollen (B. Donovan pers. comm.) Moths feed on nectar Competition with native Formal Insignificant risk – do not forage nectar-feeding insects brainstorming much as adults. Greater weed problems Formal Insignificant risk – do not forage because moths pollinate brainstorming much as adults, honeybees are flowers predominant pollinators. Inherent Genetic Insects mate with New hybrids form Species distinct. No hybrids diversity native species with native insects expected see section 3 Aceria mates with New hybrid with „gorse‟ Not expected, see section 3 other forms of the form species

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Benefits:

POTENTIAL SOURCE OF EFFECT AND/OR METHOD ASSESSMENT OF BENEFIT AND PATHWAY BENEFIT TO: BENEFIT USED TO ITS EFFECT IDENTIFY BENEFIT Life-supporting Partial control Air quality Brainstorming Possible, but benefits only occasional capacity of leads to less aerial improved by less and fleeting water, soil and application of herbicide in the air air herbicide Less non-target Brainstorming Possible, but benefits only occasional environmental and fleeting exposure Partial control Smoke from Brainstorming Possible, but benefits only occasional leads to fewer fires burning reduced and fleeting. Broom rarely fired even lit now Partial control leads Herbicide load in Brainstorming Possible, but benefits only occasional and to less ground waterways reduced fleeting. application of herbicide Reduced biomass More natural Brainstorming Possible moderate effect. More of broom reduces conditions for natural vegetation structure develops N fixation forest regeneration see section 6.1 New insects Rate of nutrient Brainstorming Possible, but minimal effect as increase faecal cycling increased limited to beneath broom production Sustainability of New insects become Food source for rare Brainstorming Only relevant to generalist predators, and native and valued abundant native predators and new insects will provide only a small introduced flora parasitoids increment to overall prey pool. See and fauna section 6.1 Increased Brainstorming Possible effect, but only beneficial if biodiversity exotic species are valued as biodiversity Agonopterix moths Brainstorming, Possible effect, but % rise in total pool of increase the previous pollinating insects negligible, and hence incidence of applications effect minimal. Also listed as a risk pollination Broom biomass and Reduced vigour Brainstorming Predicted effect minor as broom not a populations reduced increases value as a previous widely distributed nurse crop See nurse crop for applications section 6.1 Also listed as risk regenerating forest Less broom and so Smaller populations Brainstorming Benefit minimal as population of native native insects that reduce grazing insects on broom small, Syrett 1993. feed there less pressure on true abundant native hosts of herbivores Reduced non-target Brainstorming Possible effect, but temporary and damage to native occasional species from 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

herbicide use Reduced cover for Brainstorming Likely effect, see section 6.1 predators of native birds Maintenance of Broom biomass, Risk to rare and Brainstorming, See section 6.1 native habitats spread and endangered species in Reid (1998) populations reduced alpine habitats reduced Contamination of Brainstorming Effect unknown native microflora by broom rhizobia reduced Values of numerous Brainstorming, Reduced cover by broom would also habitats protected consultation have benefit to pastures, wasteland, forestry, and braided rivers see section 6.1 Intrinsic value of No additional ecosystems benefits identified

Inherent genetic No additional diversity benefits identified

B. Effects on human health and safety (including occupational exposure) As per section 6(c) of the Act, list any potential risks and benefits to human health that may be related to the conditional release of the organism(s) in New Zealand.

Risks and costs:

POTENTIAL RISK SOURCE OF RISK IMPACT AND/OR METHOD USED ASSESSMENT OF RISK TO: PATHWAY TO IDENTIFY AND ITS EFFECT RISK

Capacity of New insects Entomophobia Brainstorming Rare, no significant people to provide introduced increase in problem over for the wellbeing current alarm concerning of future insects generations Abundant insects cause Previous Insignificant effect. problems for human applications Populations high only in activity areas remote from human 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

habitation. Mite is small and cryptic, moth nocturnal, beetle relatively immobile on broom Human health Agents become Aceria mites cause allergic Brainstorming Only possible amongst abundant in the responses broom. Eriophyid mites not environment known to have this effect, see section 6.2 Agonopterix moth scales Brainstorming Only possible amongst cause allergic responses broom. Increase in general occurrence of scales miniscule Masses of insects cause Brainstorming Any effect local, density of domestic or industrial insects outside broom nuisance infestations will be low Agents bite No such records for these classes of insects. See section 6.2

Benefits:

POTENTIAL SOURCE OF EFFECT AND/OR METHOD ASSESSMENT OF BENEFIT AND BENEFIT TO: BENEFIT PATHWAY USED TO ITS EFFECT IDENTIFY BENEFIT

Human Health Reduced control of Less occupational Brainstorming Minimal if operational safety broom using exposure to requirements are implemented herbicides herbicides

C. Potential effects on the relationship of Māori and their culture and traditions with their ancestral lands, water, sites, wāhi tapu, valued flora and fauna and other taonga (taking into account the principles of the Treaty of Waitangi) As per sections 6(d) and 8 of the Act, list any potential adverse and beneficial effects on the relationship of Māori and their culture and traditions with their ancestral lands, water, sites, wāhi tapu, valued flora and fauna and other taonga (taking into account the principles of the Treaty of Waitangi). In this area it is especially important to indicate the extent to which potential effects reflect the expressed views of the Māori community. However, details on this can be dealt with under the assessment section (section 6).

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Risks and costs:

Benefits:

Key environmental outcomes Potential Potential Comment significant significant risk/cost? benefit? The continued and improved availability, No No The insects will only attack broom and its quantity and quality of traditional food close relatives. Decline in broom might resources (mahinga kai) improve the quality of mahinga kai but benefit not significant The continued availability, quantity and No No This might be enhanced by the successful quality of traditional Maori natural resources biological control of broom but benefit not significant The retention of New Zealand‟s diverse range No Yes Successful biological control would protect of indigenous flora and fauna some vulnerable native species, see section 6.3 The protection of indigenous flora and fauna Yes Yes Successful biological control would protect valued by Maori some native habitats, but would reduce a food source for kererū, see section 6.3 The purity of water (inland and coastal) and No Yes The reduction in herbicide use resulting from the need to retain and extend its productive successful biological control could reduce and life-sustaining capacity. pesticide runoff in water, see section 6 The purity of land and the need to retain and No Yes The reduction in herbicide use resulting from extend its productive and life-sustaining successful biological control could reduce capacity pesticide load on soils, see section 6. The purity of air and the need to retain and No No The reduction in herbicide use resulting from extend its productive and life-sustaining successful biological control could reduce capacity pesticide drift, but effect not significant The purity of human health and well-being No No The agents will not pose any health risk to humans. None of them bites, stings, or causes disease. Successful biological control could reduce human exposure to pesticides but benefit not significant. The restoration and retention of natural Yes Yes Natural habitats could be enhanced and habitats restored by the suppression of broom, but use of tree lucerne as a nurse crop might be adversely affected, see section 6.3

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D. Economic Effects As per section 6(e) of the Act, list the economic risks, costs and benefits that might arise to New Zealand. Also identify who will bear the risks and costs and/or who the beneficiaries are likely to be.

Risks and Costs:

POTENTIAL RISK SOURCE OF RISK IMPACT AND/OR METHOD USED ASSESSMENT OF RISK TO: PATHWAY TO IDENTIFY AND ITS EFFECT RISK

Capacity of Broom no longer a Aesthetic value in gardens Formal Not unlikely if control people to provide viable garden lost brainstorming, successful, see section 6.4 for the wellbeing species previous of future applications generations Reduced revenue to Formal Sales not permitted in most nurseries brainstorming, places, effect not unlikely if previous control successful, see applications section 6.4 Cost to gardeners of Formal Effect not unlikely if control replacing with another brainstorming, successful, see section7.4 species previous applications Less broom Reduced revenue for spray Formal Effect minimal in short-term, operators brainstorming and can be formally discounted in the long-term Reduced biomass for Formal Insignificant risk – broom sheep grazing brainstorming, replaced by other forage literature Broom replaced by more Previous No weeds are more damaging weeds applications damaging in most habitats, see section 6.4 Less flowering Tourist experience Formal brainstorm Effect minimal. Short broom degraded seasonal, and not a major component of current tourist spectacle Insects damage Damage to desirable Formal Not unlikely that insects will non-target exotic species Brainstorm, attack several weedy and species literature, non-weedy Genisteae, see experimentation section 6.4 Animal or plant Insects attack tree Reduced value of tree Literature, cost– see Jarvis et al.(2003) and health lucerne lucerne as a fodder tree benefit analysis Appendix B Agents become Allergic effects on animals Not likely, not recorded, see abundant in the section 6.4 environment Agents vector animal Brainstorming Plant-eating insects do not diseases vector animal disease 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

Agents vector plant Brainstorming No more likely than any diseases other insect to carry disease propagules. Increased risk negligible

Benefits:

POTENTIAL SOURCE OF EFFECT AND/OR METHOD USED ASSESSMENT OF PATHWAY BENEFIT TO: BENEFIT TO IDENTIFY BENEFIT AND ITS BENEFIT EFFECT

Capacity of Less broom in the Productivity of forestry cost benefit Assessed in section 6.4 and people to provide environment improved analysis, Appendix B for the wellbeing pers.comms. of future generations Productivity of pastoral cost benefit Assessed in section 6.4 and agriculture improved analysis Appendix B Reduced control costs to cost benefit Assessed in section 6.4 and farmers and foresters analysis Appendix B Reduced costs to DOC of cost benefit Assessed in section 6.4 and maintaining conservation analysis Appendix B values Reduced control costs to cost benefit Assessed in section 6.4 and other land managing depts analysis Appendix B and regional councils

E. Cultural, social, ethical and spiritual effects As per section 5(b) of the Act, list any adverse and beneficial impacts on people and communities that might arise and adversely affect or maintain/enhance (in the case of beneficial impacts) their capacity to provide for their own social and cultural wellbeing both now and into the future. Also list any ethical or spiritual risks, costs and benefits that might arise as per section 68(1)(a) of the Act. Indicate what steps have been taken to assist the identification of the effects in this area, for example, was there any community involvement?

Risks and Costs:

No cultural, social, ethical or spiritual risks and costs have been identified apart from those addressed elsewhere in section 5. Details of consultation with Māori can be found in section 6 and in Appendix A (Consultation with Māori).

Benefits:

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No cultural, social, ethical or spiritual benefits have been identified apart from those addressed elsewhere in section 5. Details of consultation with Māori can be found in section 6 and in Appendix A (Consultation with Māori).

F. Other effects (including New Zealand’s international obligations) List any remaining adverse and beneficial affects not already covered including any effects on New Zealand‟s international obligations (as per section 6(f) of the Act).

Risks and costs:

No additional risks or costs identified

Benefits:

No additional benefits identified

Section Six – Assessment of Potential Non-negligible Risks, Costs and Benefits This section entails detailed assessment of those effects identified in section 5.3 that you consider to be non- negligible . It should also provide an estimate of the likelihood of occurrence (which may be measured as frequency or probability) and the magnitude of the outcome if the adverse effect should occur. Please state why you consider an effect to be negligible before discounting it from the assessment. You should carry out your assessment firstly in the absence of any controls then in the context of the proposed controls being in place. Evaluating the effectiveness of controls is also part of the assessment process. ERMA New Zealand uses qualitative scales for assessing effects which may be of some use to you in completing this section – please refer to the ERMA New Zealand Technical Guide “ Decision Making: techniques for identifying, assessing and evaluating risks, costs and benefits” for further details. Any uncertainties associated with this assessment should also be discussed. Please cover all of these issues under each of the following headings (areas of impact) which reflect those matters referred to in Part II of the HSNO Act:

6.1 Effects on the environment (in particular on ecosystems and their constituent parts) Assess the risks, costs and benefits associated with the organism(s) to be conditionally released and the ways that they might adversely affect or improve/enhance (in the case of benefits) the New Zealand environment e.g. the life supporting capacity of air, water, soil and ecosystems; the sustainability of native and valued introduced flora and fauna; natural habitats and the intrinsic value of ecosystems; New Zealand‟s inherent genetic diversity; animal or plant health.

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Risks and costs:

The significant direct and indirect environmental risks and benefits associated with the introduction of the three control agents, or with reduction in the abundance of broom as a result of successful biological control, were identified in section 5. Assessment of non-significant risks is addressed there. The following risks are assessed here:

Potential direct environmental risks Damage to non-target plants

Potential indirect environmental risks Insect feeding reduces the use of tree lucerne for soil stabilisation Insect feeding reduces the well-being of kererū populations (assessed in section 6.3) Insect feeding reduces the use of tree lucerne for forest restoration Insect introduction adversely affects native food-webs Insect feeding reduces the value of broom for soil stabilisation, and undesirable replacement by other plants

Risk of control agents damaging non-target plants Aceria genistae The details of host-range tests conducted using A. genistae can be found in Appendix C. CSIRO Entomology (Australia) tested 33 native and other valued plant species belonging to 10 tribes of the Fabaceae. Because of the highly specific nature of eriophyid mites (section 3.4), testing of plants outside the Fabaceae was deemed unnecessary. Galls formed routinely on control plants, but no galls formed on any test plants, indicating that this mite was specific to C. scoparius. On the basis of this information, permission to release Aceria genistae in Australia was granted in 2002 (approval no. N0985). No releases have yet been made.

At the request of Landcare Research, CSIRO tested an additional 10 species from New Zealand; two lupin species of possible economic value, and eight legumes representing three of the four native genera in the Fabaceae. Several species of the genus Carmichaelia were tested. These tests were considered adequate to assess the risk not only to this genus but to Montigena novae-zealandiae. This species is closely related to Carmichaelia, and only distantly related to Cytisus (Lavin et al. 2005). Galls formed routinely on controls, but no galls formed on any test plants (Appendix C), indicating that the New Zealand plants were not hosts for this mite.

Together with the known biology of eriophyid gall mites, these two studies provide adequate evidence to conclude that there is negligible risk that A. genistae would colonise native or economically valued exotic plants in New Zealand.

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Agonopterix assimilella European sources record caterpillars of this moth feeding on several Cytisus spp., Lupinus arboreus, Genista cinerea, and G. florida, but on no plants outside the tribe Genisteae. Although C. palmensis (tree lucerne) is from Europe, it comes from the Canary Islands, and is not generally grown on the European mainland. C. palmensis has never been recorded as a host for A. assimilella in Europe, but this is not evidence that the insect does not attack C. palmensis, as the moth and the plant do not co-occur there.

Tests were conducted in Europe from 1991 to 1999 to estimate the host-range of A. assimilella. The details of the methods employed and the results obtained can be found in Appendix D. The results are summarised in Table 1 below. The acceptability of A. assimilella to 64 plant species of 26 families was tested using various test designs. Thirty-four species representing 10 tribes within the Fabaceae were tested, and within the tribe Genisteae, seven species were tested.

Newly hatched larvae could not survive and feed for longer than 7 days on any plants outside the Fabaceae. Performance was similarly poor on species within the Fabaceae but outside the tribe Genisteae, with these two exceptions. Larvae survived for a time when fed foliage of Glycine max, but this cannot be a host because no eggs were laid on this host in later oviposition tests. Although several eggs were laid on Clianthus puniceus in tests, this cannot be a host because hatching larvae could not survive on this foliage. The foliage of Sophora spp. was not attractive to larvae. From these results we conclude that no native plants or economically valuable plants outside the tribe Genisteae would be at risk from this agent in New Zealand.

A number of species of the tribe Genisteae have perceived economic significance in New Zealand, both positive and negative. Several species are invasive, or are incipient weeds in some parts of the country (Genista monspessulanum Lupinus arboreus, L. polyphyllus, Cytisus multiflorus, Spartium junceum) and themselves raise environmental concerns of varying magnitudes. Non-target attack on these species would not be considered an adverse effect. However, Cytisus palmensis is valued by some beekeepers, farmers and environmentalists. When species within the tribe Genisteae were tested, larvae did not survive when fed foliage of Ulex europaeus, Genista hispanica or Lupinus arboreus, and survived for only a few days on laburnum cultivars and Lupinus albicaulis (Appendix D). It is unlikely that these plants are hosts. However, larvae survived well when fed foliage of Cytisus palmensis and Spartium junceum (Spanish broom). Hatching larvae established on plants and formed shelters in which to overwinter on laburnum and Lupinus arboreus, but then did not survive the winter. Larvae overwintered successfully on broom and C. palmensis, but only poorly on Spartium junceum (Appendix D). It was not recorded whether these larvae completed development.

Some eggs were laid on laburnum cultivars, Spartium junceum, and Lupinus arboreus in oviposition tests in small cages, but at an intensity of less than 10% of that observed on broom controls in the same cage. Eggs were laid on C. palmensis but significantly fewer than on broom controls.

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From oviposition, feeding and development tests, it is unlikely that any species within the tribe other than Cytisus scoparius and C. palmensis would be true hosts for A. assimilella in New Zealand.

More eggs were present on tree lucerne than on broom at the start of the 1992 test. Larvae hatched and established on the plants. When these were counted just before winter, 40% of the larvae that hatched on broom produced stable larval ties in which to overwinter compared to only 5% on tree lucerne. This difference was statistically significant. Mortality of small larvae appears to be higher on tree lucerne, and it is likely to be a suboptimal host compared to broom (Appendix D). Larvae cause most damage to the host plant after overwintering.

In summary, evidence from field observations, laboratory, and field tests indicates that A. assimilella is a narrowly oligophagous species, restricted to feeding on certain species within the tribe Genisteae. Cytisus scoparius is the preferred host, but the possibility that larvae would be found on non-target plant species within the Genisteae in New Zealand cannot be ruled out on the evidence of these tests. However, with the possible exception of tree lucerne, there is no evidence that these would be substantive hosts. This conclusion is not inconsistent with the known host range in Europe.

The test results indicate that there is a risk that A. assimilella could include C. palmensis within its host range in New Zealand (Appendix D). However, it appears to survive less well on this host, and may not harbour larvae at sufficient density to cause significant damage. The possible adverse effects of non-target attack on tree lucerne are discussed later in this section and in section 6.4. There is no reason to suggest that the agent‟s response to broom would vary between Europe and New Zealand. There is no evidence that the host range of G. olivacea varies with climate.

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Table 1. Summary of the results of host-range testing of A. assimilella. Plants are listed in descending order of relatedness to broom (Lavin et al. 2005). Superscript numbers refer to tables in Appendix D.

In tests, Agonopterix assimilella was able to

hatched

Family or tribe Test species -

hatched

Lay eggs plantson test in cages Survive or for 5days 7 on cutshoots of plantstest when newly Establish on whole test plants when newly Overwinter a as larvaon whole plants

Fabaceae 4,5,6 1,2,3 4 4 Genisteae Cytisus scoparius Yes Yes Yes Yes 4,5,6 1 4 4 C. palmensis Yes Yes Yes Yes 1 Genista hispanica No 4,6 1 4 4 Spartium junceum Yes Yes Yes Yes 3 Lupinus albicaulis No 4,6 1 4 4 L. arboreus Yes No Yes No 4 3 4 4 Laburnum anagyroides Yes Yes Yes No 1 Ulex europaeus No

3 Sophoreae Sophora microphylla No 1 S. prostrata No 1 Acaciae Acacia koa No 5 1 Glycineae Glycine max No Yes 1 Phaseoleae Phaseolus vulgaris No 1 Coronilleae Coronilla varia No 1 Loteae Lotus corniculatus No 3 Robinieae Robinia pseudacacia No 1 Tephrosieae Wisteria sinensis No Galegeae Clianthus puniceus Yes4 No2 Yes 1 No4 No4 Colutea arborescens No1

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Carmichaelieae Carmichaelia arborea No1 C. compacta No3 C. crassicaule No1 C. curta No1 C. glabrescens No1 C. kirkii No1 C. monroi No1 C. muritai No1 1 C. odorata No 1 C. orbiculata No 1 C. petriei No 1 C. torulosum No 1 C. uniflora No 1 Medicago sativa No 1 Trifolieae Pisum sativum No Trifolium pratense No1

Other families Alliaceae Allium tuberosum No1 Apiaceae Petroselinum crispum No1 Asteraceae Achillea millefolium No1 Lactuca sativa No1 Taraxacum officinale No1 Betulaceae Betula pendula No1 Brassicaceae Brassica oleracea No1 Caprifoliaceae Sambucus nigra No1 Caryophyllaceae Dianthus sp. No1 Chenopodiaceae Beta vulgaris No1 Fagaceae Fagus sylvatica No1 Quercus robur No1 Grossulariaceae Ribes nigrum No1 Myrtaceae Eucalyptus gunnii No1 Fuchsia sp. No1 Passifloraceae Passiflora edulis No1 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

Pinaceae Pinus radiata No1 Pittosporaceae Pittosporum tenuifolium No1 Plantaginaceae Hebe albicans No1 Poaceae Holcus lanatus No1 Polygonaceae Polygonum lapathifolium No1 Ranunculaceae Clematis vitalba No1 Rosaceae Malus sp. No1 Rutaceae Citrus sp. No1 Salicaceae Salix sp. No1 Solancaceae Solanum tuberosum No1 Theaceae Camellia japonica No1 Urticaeae Urtica dioica No1 Vitaceae Vitis vinifera No1

Gonioctena olivacea European sources record G. olivacea from several Cytisus spp., Lupinus arboreus, Genista cinerea, G. florida and G. tinctoria. Tests designed to estimate the range of host plants used by this insect began as early as 1978, but the research reported here was conducted in Europe and in containment in New Zealand from 1982 to 2002. The details of the methods employed and the results obtained can be found in Appendix E. The results are summarised in Table 2 below. The acceptability to G. olivacea of 106 plant species of 37 families was tested in various ways over this period. Sixty-two species representing 10 tribes within the Fabaceae were tested, and within the tribe Genisteae, 21 species were tested.

There was no evidence that G. olivacea adults could feed on or lay eggs on plant species outside the Fabaceae. Even within the Fabaceae, adults and larvae could not fully utilise species belonging to nine tribes (Table 2). There was little evidence that Gonioctena olivacea would attack any native legumes if released in New Zealand. Carmichaelia and Clianthus species were not susceptible to oviposition. In the presence of broom, four eggs were laid on Sophora microphylla in one field cage oviposition test (compared with 63 on the broom control) and none in another. However, later tests showed that larvae could not establish on Sophora sp., and therefore kōwhai cannot be host for G. olivacea. From these results we conclude that no native plants or economically valuable plants outside the tribe Genisteae would be at risk from this agent in New Zealand.

As described above, a number of species of the tribe Genisteae have perceived economic significance in New Zealand, both positive and negative. In particular, Cytisus palmensis is valued by some beekeepers, farmers and 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

environmentalists. Twenty-one species from this tribe were exposed to the beetle. Newly hatched G. olivacea larvae could complete development on some species of the genera Cytisus, Genista and Lupinus but not others. When exposed in the field Genista tinctoria, Lupinus arboreus, L. polyphyllus and Cytisus palmensis plants were colonised by the beetle, but in all cases, the number of eggs deposited and the survival of larvae were lower on test plants than on broom controls. In open field tests designed to measure the propensity of G. olivacea to colonise these plants in the field, significantly more adults colonised broom than tree lucerne in 1992 (P < 0.01), but this difference was not significant in 1993 or 1994. Over all three years, 88% of the adults observed on these two plants were observed on broom. Similarly, significantly more larvae were found on broom in 1994 (P < 0.05), but this effect was not significant in 1992 or 1993. Over all years, 78% of the larvae observed on these two plant species were found on broom. G. olivacea appears to perform relatively poorly on tree lucerne, and even worse on the other test species (Appendix E).

There is additional evidence that the results presented in Appendix E may overestimate the true field host range of G. olivacea. Tests conducted in the UK indicated that Genista tinctoria might be a potential host, even though it is not an acknowledged field host there (Waloff & Richards 1958). Similarly, tests indicate that L. arboreus may be a host, but G. olivacea as only been recorded once on this species in the UK. However, taking a conservative view, the evidence presented cannot rule out the possibility that if released in New Zealand, G. olivacea might occasionally be found on ornamental European brooms, tree lupin, and possibly other lupin species. Tests suggest that these species are far less acceptable hosts than broom, but the level of attack, especially in the absence of broom, cannot be predicted with certainty. There is firm evidence that the beetle prefers broom over tree lucerne (Appendix E), but we cannot rule out the possibility that if released in New Zealand, G. olivacea might colonise tree lucerne. The effects of possible non-target attack on tree lucerne are discussed later in this section and in sections 6.3 and 6.4. In these assessments, it is assumed that tree lucerne will be as susceptible to attack as broom is. There is no reason to suggest that the agent‟s response to broom would vary between Europe and New Zealand. There is no evidence that the host range of G. olivacea varies with climate.

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Table 2. Summary of the results of host-range testing of G. olivacea. Plants are listed in descending order of relatedness to broom (Lavin et al. 2005). Superscript numbers refer to tables in Appendix E.

In tests, Gonioctena olivacea was able to

age in

Family or tribe Test species ntation

(8) or (8) to

choice tests

on test foliageon test

hatched larvae

choice choice feeding in tests

Cause Cause significantdamage as an adultfoliageto presented in no dishes Lay eggs folion test in tests dishes Lay eggs foliageon test in lab cage no Lay eggs foliageon test in large field choicecage tests Newly survive todays 6 adult(13) Larvae produced on test plants grown pla in

Fabaceae 1,2,8 5 6,7 8,13 9,10,11 Genisteae Cytisus scoparius yes yes² yes yes yes yes 7 C. beanii yes 1,2 5 8 9,11 C. palmensis yes yes yes yes 10 C. „praecox‟ no 7 Genista hispanica yes 10 G. „lydia‟ no 2 G. monosperma no no² 1,2 G, monspessulana yes 1 6,7 9,11 Genista tinctoria yes yes yes 1,2 6,7 10 Spartium junceum yes no no 6 Lupinus sp. yes 8 13 Lupinus albicaulis no no 5 L. albus yes 1,2 5 8,13 10,11 L. arboreus yes yes² yes yes yes 8 13 L. lepidus no no 8 13 L. leutiolus no no 1 11 L. polyphyllus„Russell‟ yes yes 8 13 L. rivularis no no 13 L. succulentus yes 2 8 9,10,11 Laburnum anagyroides yes no no 1 2 7 9,10,11 Ulex europaeus no yes yes no U. minor no6 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

8 Sophoreae Sophora sp. no 1,2 7 9,10,11 S. microphylla no yes no 5 9,10,11 Caesalpinieae Gleditsia triacanthos no no 5 Acaciae Acacia sp. no 2 Acacia dealbata no 1 Acacia mearnsii no 5 A. melanoxylon yes 1 Glycinieae Glycine max yes 2 Phaseolineae Phaseolus vulgaris no no² 1 Coronilleae Coronilla glauca no 6,7 C. varia no 1,2 Loteae Lotus corniculatus no 6,7 L. pedunculatus no 1,2 5 Robinieae Robinia pseudacacia no no 1,2 Tephrosieae Wisteria sinensis no 8 Galegeae Clianthus maximus no C. puniceus no1,2 no² no9,10,11 Carmichaelieae Carmichaelia sp. no8 no11 C. angustata no2 C. arborea no6,7 C. compacta no6,7 C. corrugata no6 C. crassicaule no7 C. cunninghamii no6,7 C. enysii no6 C. glabrescens no6,7 C. kirkii no2 C. monroi no6,7 C. muritai no2 no9,10,11 1 C. odorata no 6,7 C. petriei no 10 C. rivulata no 7 C. stevensonii no 2 6,7 C. torulosum no no 5 Medicago arborea no 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

1,2 7 10,11 M. sativa no no² yes no 1,2 Trifolieae Pisum sativum no no² Trifolium fragiferum no6,7 T. hybridum no6 T. pratense no2 no6,7 T. repens no6 no8 no10,11

Other families Aceraceae Acer sp. no2 no² Acinidiaceae Actinidia chinensis no2 Apiaceae Angelica pachycarpa no2 no² Araliaceae Pseudopanax arboreus no2 Asteraceae Lactuca sativa no2 Olearia haastii no7 Betulaceae Betula pendula no2 Brassicaceae Brassica oleracea no2 Caprifoliaceae Sambucus nigra no2 no² Caryophyllaceae Dianthus sp. no2 Chenopodiaceae Beta vulgaris no2 Convolvulaceae Calystegia marginata no2 Cucurbitaceae Cucurbita maxima no2 no² Ericaceae Rhododendron cv. no2 no² Fagaceae Nothofagus fusca no2 Gramineae Cortaderia jubata no2 Grossulariaceae Ribes nigrum no2 no² Lamiaceae Lavandula dentata no2 no² Lilliaceae Allium sp. no2 no² Malvaceae Hoheria sexstylosa no2 Myrtaceae Meterosideros umbellata no2 Oleaceae Jasminum polyanthum no2 no² Onagraceae Fuchsia excorticata no2 Pinaceae Pinus radiata no2 no² Pittosporaceae Pittosporum tenuifolium no2

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Plantaginaceae Hebe armstrongi no2 H. rakaiensis no7 H. stricta Polygonaceae Muehlenbeckia complexa no2 Proteaceae Leucodendron longigerum no2 Ranunculaceae Clematis forsteri no2 Rosaceae Prunus sp. no2 Rubiaceae Coprosma propinqua no2 Rutaceae Citrus limon no2 Salicaceae Populus sp. no2,8 no8,13 P. balsamifera no13 P. tremuloides no8 Salix sp. no8 S. babylonica no2 no² S. hookeriana no8 no13 Scrophulariaceae Verbascum sp. no7 Solancaceae Lycopersicon esculentum no2 Violaceae Melicytus crassifolium no2 Vitaceae Vitis vinifera no2 no²

Possible adverse effects of insect feeding on the well-being of kererū populations For most of the year, native wood pigeons (also known as kukupa and kererū) feed largely on fruits. However, when few fruits are available (especially in early spring) pigeons feed on green foliage, including the buds and foliage of tree lucerne and broom. The host range tests reported above cannot rule out the possibility that Chamaecytisus palmensis will become field hosts for Agonopterix assimilella and/or Gonioctena olivacea released in New Zealand. The risk that successful biological control of broom and/or reduction in the vigour of tree lucerne following non-target attack would reduce the viability of kererū populations is assessed in Section 6.3.

Possible adverse effects of insect feeding on the use of tree lucerne for soil stabilisation Litter builds up rapidly under tree lucerne, and this promotes the restoration of disturbed or depleted soils (HBRC 2002, MAF 2001, see Appendix B for more details). The host-range tests reported above cannot rule out the possibility that tree lucerne will become a field host if these agents are released in New Zealand. However, the use 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

of tree lucerne for stabilising soils would be significantly compromised only if non-target attack by Agonopterix assimilella and/or Gonioctena olivacea caused the death or debilitation of a significant proportion of the tree lucerne planted for this purpose. This outcome is considered unlikely. Both insects performed less well than broom in host-range tests. It remains uncertain whether these agents will persist on tree lucerne in New Zealand, or what damage these insects might cause. If insect attack reached a level sufficient to compromise the value of tree lucerne for this purpose, there would be concomitant environmental benefits from control of broom that would outweigh those costs.

The effects of any impact could be mitigated by insecticide application (Jarvis et al. 2003), or by using another species for soil conservation planting. The cost of insecticide application has been used to estimate the cost if tree lucerne was lost (section 6.4, Jarvis et al. 2003), but this may not be practical. G. Eyles (Hawke‟s Bay Regional Council, pers. comm.) states that there may be few other options for planting dry hill country in Hawkes Bay, but in Marlborough the Starborough-Flaxbourne project is using salt bush for this purpose (Appendix B). The economic ramifications of providing alternatives are presented in section 6.4.

Possible adverse effects of insect feeding on the use of tree lucerne for forest restoration Older more open stands of tree lucerne provide good protection for naturally regenerating native shrubs seedlings in higher rainfall areas (Sheppard & Bulloch 1986). The canopy declines after 15–18 years, allowing light to underlying shrub and tree seedlings. These characteristics make tree lucerne a suitable nurse crop for fostering native vegetation (see Appendix B for more detail). Tree lucerne also attracts frugivorous birds that deposit native tree seeds consumed in adjacent forests, increasing the diversity of the seed bank and developing seedlings under the bushes (Mick Park, Te Atiawa Manawhenua ki te Tau Ihu Trust, pers. comm.).

Although there is evidence that Agonopterix assimilella and Gonioctena olivacea prefer broom over tree lucerne (section 6.1), host range tests reported cannot rule out the possibility that tree lucerne will become a field host if released in New Zealand. Non-target attack by A. assimilella and/or G. olivacea would only compromise the ability of tree lucerne to nurse native seedlings if most plants used for this purpose were killed by insect attack. This is considered unlikely. The most likely consequence of any non-target attack on tree lucerne by these insects would be reduced plant vigour and reproduction. This could reduce the rate of litter accumulation, but plants would still provide shelter for developing seedlings. Sub-lethal attack might reduce the maximum age of bushes, which could even accelerate the process of succession. Attractiveness to kererū might be reduced but not eliminated. If insect attack reached a level sufficient to compromise the value of tree lucerne for this purpose, there would be concomitant environmental benefits from control of broom that would outweigh those costs.

The value of Chamaecytisus palmensis (or broom) as a good nurse plant for forest regeneration can be questioned. Research now shows that forest ecosystems that regenerate under gorse following disturbance differ at all trophic levels from those that develop under the native species kānuka (Harris et al. 2004; Sullivan et al. in press; www.landcareresearch.co.nz/research/biodiversity/landscapesprog/workshops/PeterWilliams.pps), and these 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

successions do not converge. Like gorse, broom and tree lucerne fix nitrogen. The assemblage of species that colonises the N-enriched soil beneath broom or tree lucerne is also likely to be different from that found under most native nurse crops. The climax forest ecosystem is likely to function differently from that developed under native shrubs, and will not represent a „restoration‟ of local flora and fauna (also see Appendix B).

Possible adverse effects on native food-webs of introducing three new species Broom is a highly adaptable species and occupies a wide range of habitats and climates, from lowland riverbeds to forest margins and subalpine shrublands (Williams 1981). It occurs throughout the North Island, and as far south as Stewart Island (Webb et al. 1988). It is spreading into new habitats, and as it does, it is massively altering native ecosystems. Biological control aims to limit those ecosystem changes, but biological control itself involves change. There would be a net adverse effect if the adverse effects of imposing control exceeded the benefits achieved by limiting or reversing the adverse effects of broom.

The establishment of Aceria genistae, Agonopterix assimilella and Gonioctena olivacea would introduce new elements to the ecosystems found in the vicinity of broom plants. The introduction of these three control agents could indirectly affect the environment either by (1) displacement of native species through competition for resources or (2) modifying the way other species in the ecosystem interact.

Displacement of native species Syrett (1993) surveyed the phytophagous fauna of broom in detail in Canterbury, and in less detail elsewhere. Few species were recorded as common, and she considered the fauna depauperate compared with the fauna found on broom in Europe. Most of the species were rare. Most were recorded as adults, were probably transient, and not closely tied with the host plant at all. While many native insect species were recorded from broom, none relied on broom for their existence. As most of the insects recorded were generalist species, any woody shrubs (including native species) that replace the broom will provide support to many of the species listed. As a result of these observations, the applicants conclude that no phytophagous insects would be displaced from broom-invaded ecosystems by the three proposed agents. Further, reduction in the abundance or biomass of broom through biological control would restore faunal patterns closer to those existing before broom expansion took place.

All stages of Gonioctena olivacea and Agonopterix assimilella occur on the host plant, or in the leaf litter beneath, and would be available to native parasitoids and predators.

Modification of interactions Food webs will be altered if the addition of the control agents to the ecosystem changes the abundance of resident natural enemies, and this significantly affects other animals or the plants on which they feed. The control agents will only be common where broom occurs. Where broom is not common, the marginal increase in prey biomass 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

contributed by introduced control agents will be small, and any changes in food web structure will be insignificant. Where broom forms monocultures, the agents may well form a significant proportion of the prey biomass available to natural enemies. At the same time, the presence of the broom infestation will already have severely modified food webs locally. Effects on food webs would fall away rapidly with distance from broom monocultures.

Possible effects vary for the different proposed agents. Aceria genistae occupies galls only on broom. Except during dispersal, all stages are hidden within the gall or the overwintering bud, and are not generally available to predators. Typhlodromus pyri (Phytoseiidae) (an introduced species that is common in New Zealand) has been found inside A. genistae galls in Europe (A. Sheppard, CSIRO Entomology, pers. comm.). However, mites in galls are not thought to be severely affected by generalist predators such as this (Zhi-Qiang Zhang, Landcare Research, pers. comm.). There may also be specialist predators of native eriophyid species on kaka beak, native brooms and kōwhai (Manson 1984) that could colonise these galls. This is not known. The introduction of a new gall-forming mite may therefore increase predatory mite populations in the immediate vicinity of infected broom bushes, resulting in higher predation of populations of native mite species than if the introduced eriophyid was not present. However, any adverse effect would be limited to the immediate vicinity of the galled broom bushes, and would ameliorate quickly with distance. It is likely that the invasion of the native habitat by broom would be a greater perturbation to the ecosystem than the presence of mite galls.

Eggs of both A. assimilella and G. olivacea are laid on the leaf surface, and would be available to any egg parasitoids and predators that frequent shrublands in New Zealand. Little is known of this fauna, or whether the agents would be susceptible to it.

There are no parasitoids recorded from G. olivacea (J. Berry, Landcare Research, pers. comm.). There are no native leaf-feeding chrysomelid beetles, and so there are unlikely to be specific parasitoids for G. olivacea larvae or pupae. Parasitoids have been introduced from Australia to help control large, exotic leaf-feeding chrysomelids that attack eucalypts (J. Berry, Landcare Research, pers. comm.). These are specialist parasitoids, and will not attack G. olivacea in New Zealand. It is not known which if any native generalist parasitoids could take advantage of these new prey sources.

A number of parasitoids of Agonopterix species are known overseas, but none of these species are known in New Zealand. Four parasitoids of oecophorid moths are known in New Zealand (J. Berry, Landcare Research, pers. comm.). Although there are parasitoids that appear capable of parasitising A. assimilella larvae and pupae, it is interesting to note that none of these have yet been recorded attacking the related gorse control agent A. umbellana in Canterbury (R. Hill, pers. obs.). This species was introduced over 10 years ago. If these parasitoids do not colonise gorse, it is logical to assume that they will not be found in broom either.

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The pupae of A. assimilella and G. olivacea could be prey for generalist predators. Moths and beetles are attacked by spiders and birds. If broom was present as a monoculture, and G. olivacea and A. assimilella were common on broom, agent biomass would make up a large proportion of the available resource. However, in this case food webs would comprise only the broom insects and associated natural enemies, as all other vegetation and associated fauna would be excluded. With increased patchiness of the vegetation, broom control agents would make up a declining proportion of the overall prey resource, and would have a decreasing influence on the food webs. Where broom was not common, G. olivacea and A. assimilella would provide only a small increase in the overall prey pool available to generalist parasitoids and predators

In summary, no clear pathways have been identified by which the introduction of these three species would have significant adverse effects on native ecosystems. Again, itt is likely that the invasion of the native habitat by broom would be a greater perturbation to the ecosystem than the introduction of the control agents. If agents became so common as to dominate food webs, even locally, then there would probably be concomitant environmental benefits from attack of those agents on broom.

Possible adverse effects on the value of broom for soil stabilisation, and undesirable replacement by other plants Broom is perceived to have value as a ground cover for soil stabilisation and rainfall interception, largely on the basis that broom cover is better than no cover. Biological control of broom would be detrimental to these attributes only if wholesale and rapid destruction of broom plants led to persistent bare ground, but this is unlikely. It is more likely that successful control would lead to a gradual rather than a precipitate decrease in the vigour and/or abundance of broom. This decline would facilitate productive land use such as exotic afforestation or the restoration of pasture for grazing where appropriate. Where no further management was applied, it is unlikely that the ecological gap created by biological control would be left unfilled. In lowland areas removal of broom would lead to slow replacement by native plants, or other scrub weeds such as gorse (Ulex europaeus) and elder (Sambucus nigra) (1983), without significant loss of soil stability. In upland areas, sweet briar and the native matagouri (Discaria toumatou) could replace broom in the absence of grazing. As broom is arguably the most aggressive exotic coloniser, replacement by another exotic species is unlikely to increase adverse effects on soil stability or flooding.

Broom is an aggressive coloniser that is spreading into unmanaged or laxly grazed grasslands in many parts of the country. One of the greatest benefits of (even partially) successful biological control would be the limitation of broom invasion.

Broom is a host of the parasitic native mistletoe (Reid 1998), but it is just one host amongst many, and reduction in broom would not adversely affect populations of this parasite.

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Benefits:

The significant environmental benefits that would accrue from reduction in the costs associated with broom as a result of successful biological control were identified in section 5. Assessment of non-significant benefits is addressed there. Monetary benefits of successful biological control of broom to the Department of Conservation and other organisations are assessed in section 6.4. There are additional benefits to be gained because budgetary constraints allow treatment of only a fraction of the area adversely affected by broom, because it is technically impossible to selectively control broom in many native ecosystems (Keith Briden, Department of Conservation, pers. comm.), and because most benefits are non-monetary.

Broom currently occupies only a proportion of the land it could potentially colonise. Overton et al. (in Jarvis et al. 2005) predicted that broom has the potential to invade approximately five times the area it presently occupies in the Manawatu region of New Zealand alone, even though broom is already widespread there. The potential for expansion would be significantly greater in regions such as Northland or Fiordland, where broom is newly adventive. Therefore, the greatest potential benefit of biological control may result from preventing or reducing the impacts of broom invasion over the large tracts of suitable habitat that it has not yet colonised.

Biological control could provide the following: Protection of threatened plant species Reduced invasion of vulnerable ecosystems Protection of river-nesting birds Protection of succession pathways Protection of landscape values.

Reid (1998) assessed the risk that weeds posed to 117 ecologically vulnerable plant species in New Zealand. Broom was listed as a threat to 11% of these species, and along with gorse and three grass species, it was the weed most recorded as a threat to these native plants. The reasons varied. In some cases the endangered plants were at collateral risk from broom control operations, but in other cases habitat invasion by broom and/or direct competition were seen as major threats to species survival. Broom is of limited distribution, and currently poses greatest threat to lowland habitats such as riverbeds, the home of rare native brooms such as Carmichaelia kirkii. However, Scotch broom grows to an elevation of 1500 m in Europe, and already forms dense stands above the treeline in New Zealand (S. Fowler, Landcare Research, pers. comm.). As the distribution of broom increases, broom is likely to invade and dominate vulnerable, short-stature subalpine plant communities nationwide. This threatens individual plant and insect species, the integrity of the ecosystems, and New Zealand‟s montane landscape values. In Tongariro Taupo Conservancy broom colonises virtually all low stature vegetation types including all tussock grasslands (mainly red but also areas of hard, silver and blue), sub-alpine and alpine shrublands, frostflats (depressions where cold ponding occurs), cliffs and even in some geothermal kanuka habitats. It directly threatens habitats of rare and endangered species such as Pittosporum turneri, Coprosma 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

wallii and Pimelea tomentosa. Many areas of lower conservation value go untreated because of lack of resources, which means that broom is now part of a different pathway successional cycle (Nick Singer, DOC, pers comm.). Eradication of founding plants is a major management task for Park staff at a cost of at least $29,500 in 2003 (Jarvis et al. 2003), and $60,000 per annum now (Nick Singer).

Broom can colonise widely varying habitats, and is also a major threat to wetlands such as Kaimaumau Swamp, where options for effective weed management are limited (Jarvis et al. 2003; Keith Briden, Department of Conservation, Christchurch, pers. comm.).

A review of high country pastoral leases is underway. As a result of this review, considerable areas of mountain lands will be retired from grazing by sheep shortly. This grazing currently suppresses and slows invasion by a range of weeds. Reduction in grazing will accelerate the invasion of the high country by woody weeds, of which broom is probably the most aggressive (Keith Briden, Department of Conservation, Christchurch, pers. comm.).

The upper reaches of South Island braided riverbeds are bare mobile gravels that are home to threatened plants, and the nesting sites for rare and endangered birds. Legume shrubs efficiently colonise the mobile gravels and accrete the substrate into islands. Broom is a key species in this invasion, and in some cases is the only species involved. It is probably the tallest and hardiest of these invaders. As well as changing the hydrology of these rivers and covering nesting habitat, the shrub vegetation harbours predatory cats and mustelids. These reduce the nesting success of many birds, including highly vulnerable species such as the wrybill and the black stilt (Owen 1998; http://www.forestandbird.org.nz/publications/magazine/1999/august/BraidedRivers.asp).

As observed above, succession through broom will probably produce an ecosystem that is profoundly different from one nurtured by native plant species such as kanuka (Sullivan et al. in press). Successful biological control of broom would lead to fewer broom monocultures, and a greater proportion of forest restoration occurring through predominantly native nurse crops.

A successful 5-year effort to control broom in the upper Rangitata River, funded by LINZ, local government and local landowners has successfully controlled broom that threatened biodiversity values, disrupted river use by anglers and trampers, and downgraded landscapes. (http://www.linz.govt.nz/rcs/linz/pub/web/root/supportinginfo/AboutLinz/Publications/Landscan/landscansept02/i ndex.jsp#1). Subsequently this was the setting for Edoras in „The Lord of the Rings – The Two Towers‟. The same threat to landscape values is evident in Tongariro National Park; „Here in Tongariro National Park, it threatens every view of the area, and smothers the native plants.‟ (http://www.doc.govt.nz/Explore/001~National-Parks/Tongariro-National-Park/007~The-Invaders.asp). Successful biological control of broom would reduce the rate of spread, and assist the conservation of landscape values.

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Earlier in this section the possible interactions between these three species and native food webs were discussed as risks. Overall, it is as likely that these interactions will be beneficial as detrimental to the environment.

The biological control programme against broom aims to reduce the plant density, survival, growth rate, height and biomass accumulation, seed production and rate of spread of broom. How well the introduced control agents will achieve this is uncertain, although ecological studies and the history of similar biological control programmes indicate that successful control is not unlikely (Appendix B). The level of control of broom is likely to be geographically variable, and more beneficial in some ecosystems than others. However, reduction in the competitiveness, size, or rate of spread of broom is likely to have environmental benefits at all levels of control. The potential for achieving non-monetary environmental benefits is enormous, but it is not possible to predict how large the benefits will be, or where they will occur.

6.2 Effects on human health and safety (including occupational exposure) Assess any potential risks, costs and benefits to human health that may be related to the conditional release of the organism(s) in New Zealand.

Risks and costs:

No significant risks identified. None of the agents has biting mouthparts or the ability to sting. Database and web searches reveal no records of any of the species being implicated in human health issues.

Benefits:

Successful control of broom would eventually reduce the amount of herbicide applied to infestations in New Zealand, and so reduce the frequency of exposure of the public and spray operators to the toxic elements of herbicides. Assuming that herbicides are currently applied according to label requirements and in accordance with requirements for occupational safety, the benefits to human health are presumably marginal.

6.3 Potential effects on the relationship of Māori and their culture and traditions with their ancestral lands, water, sites, wāhi tapu, valued flora and fauna and other taonga (taking into account the principles of the Treaty of Waitangi) Assess any potential adverse and beneficial effects on the relationship of Māori and their culture and traditions with their ancestral lands, water, sites, wāhi tapu, valued flora and fauna and other taonga (taking into account the principles of the Treaty of Waitangi). If there are potentially non-negligible effects to consider in this area, it is expected that consultation will have occurred with Māori. Give details of this in the space provided (see the User Guide for what is required). 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

Risks and costs:

The key issues identified by Ngāi Tahu and by other Māori correspondents were as follows:

Potential impacts on native broom or other native species Ngāi Tahu raised issues surrounding non-target attack on native plants, the interaction of introduced agents with native insects, and the potential need to control the agents themselves in the future. These issues are covered in detail in section 6.1.

Ngāi Tahu also questioned the choice of plants tested (Appendix A). It is rarely possible to test as many plants (or different populations of a single species) as the public would wish because of cost. Instead, scientifically sound, and internationally accepted protocols for selecting a representative panel of test plants have been established (Wapshere 1974) and were used in this case. Concerns raised by Ngāi Tahu about „functional similarity‟ between plants are also covered when standard host-plant selection procedures are used (Wapshere 1974). The reasons for selecting the plants tested against each of the proposed control agents can be found in Appendices C–E.

The agents are expected to spread throughout New Zealand, but test plants were from a single locality. We believe the populations tested can represent the species nationwide.

Customary use of introduced species The Ngāi Tahu risk assessment acknowledged that broom was out of control, but noted that it had benefits for tāngata whenua as rongoā, shelter for crops, as food for birds (see below) as a nitrogen fixer, and for erosion control. Biological control aims to reduce the abundance, spread and vigour of the weed, and if successful, broom will remain a common plant. The opportunity for harvesting for medicinal purposes will remain. If necessary, broom could still be transplanted for shelter, or existing plants could be utilised for that purpose. If control was successful, then affected broom might well have a shorter life, and might be less robust. If this negated its value, then less invasive species could be substituted for that purpose. The duality of the value of broom in forest restoration is discussed in section 6.1. While it could be argued that any shrub cover is beneficial to some land, the applicants suggest that any perceived land management benefits of broom in some places are offset by the aggressive invasion of land where the weed is not wanted.

Broom will never become rare, and so its harvesting as rongoā will not be compromised.

The value of tree lucerne Te Hapū o Ngāti Wheke (Appendix A) and Te Atiawa Manawhenua ki te Tau Ihu Trust (Mick Park, pers. comm.) use tree lucerne to enhance habitat restoration. The potential effects of non-target attack on the value of tree

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lucerne for sheltering native plants are discussed in section 6.1. The potential effect of non-target attack on the value of tree lucerne as food for kererū is addressed below.

This application takes the precautionary view that we cannot rule out possible non-target attack on tree lucerne by two of these agents. However, laboratory tests indicate that tree lucerne is not a preferred host, and if attack occurs at all, it will probably be at lower levels than on the target weed. If the biological control project is not successful, and does not inflict serious damage on broom, it is unlikely that there will be any significant damage to tree lucerne.

Potential effects on the restoration of kererū A review of the importance of broom and tree lucerne to the diet and well-being of kererū can be found in Appendix B.

Kererū is a taonga species for Ngāi Tahu, and for iwi nationwide. Ngāi Tahu is actively working on recovering the species to the point where sustainable cultural harvest can be considered acceptable in the future (Appendix A), as harvesting tītī is today. The same native wood pigeon is called kukupa in the north, and a similar recovery project is underway at Motatau, Northland (http://forestandbird.org.nz/publications/magazine/1997/november/kukupa.asp, Innes et al. 2004).

Native pigeons feed mostly on fruits, however, in some places, and at some times of the year fruits are rare, and birds maintain themselves by feeding on the foliage and buds of various trees and shrubs. Although both projects appear to yield improved bird populations, the ecosystems are very different. In the South Island a favoured food at this time of year is kōwhai (Sophora sp.). Kōwhai has become increasingly rare in the east of the South Island, and kererū have substituted exotic legume shrubs such as broom and tree lucerne. Ngāi Tahu sought certainty that the proposed programme would not adversely affect the well-being and enhancement of kererū (Appendix A). Although food sources are important, research shows that the key factor that limits population growth in native pigeons is predation rather than food quality. The life span of pigeons on offshore islands is up to 15 years, but because of high levels of predation, only 3–5 years on the mainland (www.forestandbird.org.nz/dawncchorus/kereru.asp). When possums and ship rats were controlled at Motatau, nesting success was high (Innes et al. 2004). Some of this increased success was attributed to improved diet, but only because the reduction in possum grazing improved dietary options available to the birds. Legume shrubs were not mentioned as alternative food sources at Motatau.

Pigeons feed heavily on broom and tree lucerne in Canterbury during the critical period of late winter and early spring, but can fly many kilometres to seek a range of acceptable exotic (such as willows, poplars and Prunus) and native plants (kōwhai). Although broom and tree lucerne appear important to pigeons on Banks Peninsula, neither of these species is present in Motatau, and so cannot in themselves be critical to pigeon population recovery. 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

Successful biological control of broom in Canterbury would reduce the vigour, reproductive capacity, and density of broom bushes. Although unlikely, the same could conceivably happen if there was serious non-target attack on tree lucerne. In neither case would these species become rare in the Canterbury environment, and would still be available to kererū, albeit as smaller plants at lower density. If the introduction of these biological control agent does not result in biological control of broom, there will be no significant reduction in abundance of either broom or tree lucerne. Any effects could be mitigated in the long-term by planting native species such as kōwhai (www.kereru.org.nz)

Monitoring Ngāi Tahu expressed the wish that detailed measurement of impacts on the target weed and on non-target species should be mandatory for such projects.

The simple establishment and spread monitoring planned for this project is presented in section 4.5. It is always desirable to measure the success or otherwise of biological control agents, but this is a difficult process to plan. Once released, biological control agents often persist at such low density that detection is difficult for some years. Population build-up to the point of equilibrium density (and therefore maximum impact) also usually takes many years. It would not be valid to measure impact until equilibrium density had been achieved, and this is likely to be many years hence. Just how many years is not predictable. This is beyond the horizon of most funding bodies, which are usually not interested in funding this style of research at all. It is certainly beyond the present scope of the applicants.

Predicting agent behaviour Ngāi Tahu expressed concerns about the nature and extent of existing knowledge about how the organisms behave in a new environment, and thus affect native species. There are two issues here. The population growth of introduced species is governed by the effects of any resident natural enemies the species might attract, and how developmental and reproductive rates respond in the new climate. The applicants acknowledge that whether a species establishes in New Zealand, how quickly populations build, and the final equilibrium population density are difficult to predict. It is important to distinguish these population processes from the physiological processes involved in host plant selection. These are genetically fixed behaviours that are only amenable to evolutionary change, and do not change with environment. Knowledge about this process is provided by host range testing.

Benefits: The environmental and economic benefits that would accrue to Māori as a result of successful biological control of broom are those that accrue to all New Zealanders, and are assessed elsewhere in section 6. The impact assessment prepared by Ngāi Tahu did not identify any benefits specific to Māori.

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Consultation with Māori: The information pack was circulated to a list of 82 iwi, hapū, and Māori organisations (16 of which are papatipu rūnanga of Ngāi Tahu). This list was supplied by ERMA New Zealand. The packs were distributed in mid- September, and responses were requested by 31 October (6 weeks). In fact, responses were accepted until the end of November.

The consultation document is reproduced in Appendix A. It described how the applicant intended to assess the risks, costs and benefits surrounding the proposed introduction of Aceria genistae, Agonopterix assimilella and Gonioctena olivacea in the application, and asked each organisation to identify any issues that were inadequately or not covered in those plans. Information sheets about safe practice of biological control of weeds were included, along with answers to „frequently asked questions‟. Recipients were given the option of responding by form letter (a self-addressed envelope was included), by email, by phone, and were invited to seek more interaction with the applicants. The offer to meet kanohi ki te kanohi was not explicit, but such meetings would have been undertaken willingly had respondents requested it. A panui soliciting responses about the proposed application was lodged on the „hot topics‟ section on the Federation of Māori Authorities website.

Email, written, and verbal responses were received from 10 sources (12% of correspondents), two of which were from rūnanga of Ngāi Tahu. Otherwise, respondents felt that the information provided in the information pack either allayed concerns they held, or gave them confidence that the ERMA process would be adequate to address their concerns. The applicant entered into dialogue on all specific issues raised by respondents as and when requested. In none of the written responses, or the follow-up phonecalls was a specific request made for a face-to- face meeting.

Toitū te Whenua, the Natural Resources and Environment Unit of Ngāi Tahu, prepared a risk assessment following an internal process within the tribal structure of Te Rūnanga o Ngāi Tahu. Ngāi Tahu considers broom to be a serious environmental weed, and supported in principle controlling its spread. The assessment cited the potential environmental benefits of reducing herbicide use on the land. It generally supported the concept of biological control but was cautious because of uncertainty over how agents might behave in a new environment. The assessment is reproduced in Appendix A.

6.4 Economic effects Assess the potential magnitude and distribution of the economic risks, costs and benefits. Effects on third parties and to New Zealand of the proposed conditional release need to be specifically evaluated. Applicants should provide a cost benefit analysis.

Risks and costs: The information summarised in this section is drawn largely from a detailed analysis conducted in 1998/99 of the costs and benefits of introducing an additional biological control agent for broom (Jarvis et al. 2003). Recently 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

this report has been summarised and submitted for publication (Jarvis et al. 2005). Both documents can be found in Appendix B.

The host range tests assessed in section 6.1 examined the risk posed to C. palmensis by the proposed control agents. The risk of attack by Aceria genistae is insignificant. Scotch broom was highly preferred over tree lucerne by Gonioctena olivacea. The applicants take a conservative view, and assert that these results cannot rule out the possibility that C. palmensis will become a field host for this species. Similarly, if Agonopterix assimilella is released in New Zealand, it is possible that it could be a field host for this insect. The economic consequences of this possible attack are assessed here, and as the degree of future damage cannot be predicted with certainty, the worst-case scenario is assumed, in which the economic benefits of this plant to New Zealand agriculture are lost.

Possible adverse effects to pastoral farming from non-target attack on tree lucerne For many years tree lucerne has been recommended as a potentially useful supplementary late summer and autumn forage for sheep and cattle in drought-prone areas of New Zealand (Douglas et al. 1998). The agronomic values of tree lucerne are summarised in Appendix B.

Jarvis et al. (2003, 2005) undertook a broad-brush approach to estimating possible adverse effects on fodder planting of non-target attack. It was assumed any adverse effects that could occur as a result of herbivory by G. olivacea and A. assimilella would be overcome by spraying with insecticide once a year (costing $45/ha), in late spring, when the chemical can be expected to kill adult G. olivacea beetles and mature A. assimilella larvae. The analysis assumed that all 10 000 ha of land that could potentially benefit were planted, and a worst-case upper bound cost of $0.45 million per year to spray 10 000 ha once a year was established (Jarvis et al. 2003, Appendix B, Table 3). Although a valid economic approach to assessing the cost, controlling the agents on extensively planted tree lucerne would not be practical, and heavy non-target damage would probably render tree lucerne useless as a drylands fodder crop.

Any adverse effects are likely to be less than complete for several reasons. Firstly, it is important to note that it is not certain that biocontrol will adversely affect tree lucerne. Uptake by New Zealand farmers is not certain. Its potential use through New Zealand is estimated at 5–10 000 ha (G. Douglas, pers. comm. 1999 in Jarvis et al. 2003), but despite its apparent value only 30–50 ha of summer-dry pastureland had been planted with tree lucerne by 1999. Uptake still appears to be low, but there is little information about the area of pastoral land under this system of production in New Zealand. Insufficient tree lucerne has been grown on farms to indicate it will be planted widely in the future (Appendix B). G. olivacea and A. assimilella lay eggs on the leaves and young stems of broom in summer and autumn, the time at which plants are grazed by stock. It is likely that destruction of eggs during stock grazing will minimise the number of damaging larvae establishing on tree lucerne in pastures.

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Possible adverse effects to beekeeping from non-target attack on tree lucerne, and damage to broom Chamaecytisus palmensis produces abundant white pea flowers that develop in late winter to early spring. Beekeepers value naturalised tree lucerne highly because it flowers in late winter and early spring when there is a dearth of pollen and nectar sources (Walsh 1978). Beekeepers feel that tree lucerne provides an early boost to hive vigour.

The showiness and abundance of the white flowers in late winter may exaggerate the real importance of tree lucerne (as opposed to other contemporary resources such as willow) in providing this ecological service. Webb and Shand (1985) found that bumblebees were the most frequent and important flower visitors. Honey bees were not strong enough to legitimately enter fresh mature flowers to seek nectar, and relied on illegitimate visits through the side of the flower (energy-consuming and inefficient), visiting older flowers already tripped by bumblebees, or taking nectar directly through the calyx using holes cut by bumblebees. The large amount of seed set by tree lucerne is not a strong indicator of pollination by bees either, as tree lucerne is self-compatible, and fertilisation often occurs in the bud before flowers become available to pollinators (Webb and Shand 1985). The size of the tree lucerne flower resource does not therefore accurately reflect its importance as a nectar source for honey bees.

As C. palmensis is of limited distribution in New Zealand, these benefits are not evenly distributed geographically, and as beekeeping is conducted nationwide, this plant is clearly not in itself critical to the success of beekeeping in New Zealand. Despite its perceived value, beekeepers do not actively manage tree lucerne for this purpose.

Broom does not produce nectar for honey production. However, brood-rearing in honeybee colonies depends on adequate pollen supplies (Sandrey 1985 in Jarvis et al. 2003), without which hives may experience protein deficiency, especially in spring when they begin to build up pollen stores for the season. Broom flowers in late spring and provides pollen with high levels of amino acids and protein and is considered a good source of pollen for the beekeeping industry (Day et al. 1990 in Jarvis et al. 2003).

Beekeepers can deploy strategies to overcome pollen shortages in spring (Jarvis et al. 2003). The adverse effects on the beekeeping industry that might result from successful biological control of broom were estimated by costing the alternatives for the beekeepers that claimed a reliance on broom pollen. A survey of beekeepers was conducted (Jarvis et al. 2003). The details can be found in Appendix B. Approximately 55% of beekeepers responded to the survey, representing 85% of New Zealand‟s hives. The estimated annual cost to beekeepers ranged from $1.178 million, assuming a 25% reduction in broom, to $2.408 million for a 95% reduction in broom (Jarvis et al. 2003, Appendix B, Table 3).

Wild hives in the North Island have been largely destroyed since varroa mite arrived in New Zealand, reducing competition with managed bees for early spring nectar and pollen. 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

Possible adverse effects to soil conservation from non-target attack on tree lucerne Tree lucerne is recommended for stabilisation and rehabilitation of vulnerable soils, especially in dry areas (see Appendix B for details). Any adverse effects on soil conservation through non-target effects on tree lucerne could be mitigated by planting alternative species (but see section 6.1), and the maximum cost of such non-target damage can be estimated in this manner. Enquiries at plant nurseries in 1998 indicated that approximately 50,000 tagasaste plants per year are produced for soil conservation purposes, and each plant costs approximately $1. There are alternative species for soil conservation planting, but these may cost $4 per plant. The annual cost of switching to an alternative species for soil conservation planting would be $0.15 million annually (Jarvis et al. 2003, Appendix B, Section 6.1). This would only be required if biological control killed a significant proportion of plants, a scenario that is considered very unlikely.

Possible adverse effects to amenity plantings from non-target attack Host-range testing (section 6.1, Tables 1 & 2) and literature records in Europe indicated a risk that Agonopterix assimilella and Gonioctena olivacea might be found on other plants within the tribe Genisteae that are valued as garden species in New Zealand. The shrubs within this group are relatively short-lived, and at worst, non-target damage could mean early replacement of plants as they become moribund. However, performance on non-target plants was less intense than on broom in tests, and incidental damage to garden shrubs may be small, and treatable using pesticides freely available at garden centres. Species such as Spartium junceum are not common in gardens, and overall the risk posed is considered insignificant.

The risk of replacement by a more damaging weed Broom is arguably the most aggressive and persistent of New Zealand‟s scrubweeds. Popay et al. (2002) surveyed farmers, and found that 24 of 53 respondents listed broom amongst the top three most serious woody weed problems, after gorse and blackberry. It is unlikely that these species would be any more or less damaging than broom to those farmers.

Broom is considered to be the most competitive of the weeds affecting forestry in the North Island (M. Parrish in Jarvis et al. 2003) and replacement by other weeds would not worsen this situation. Successful biological control of broom would offer land managers the opportunity to actively renovate invaded land for productive use in farming or forestry. However, some land that is currently covered with broom would never be renovated, even if biological control was successful. This includes conservation land, riverbeds, and land for which such investment is simply not efficient. For this land, any gaps created by successful biological control of broom will be filled, either by native plants, or by other exotic shrubs, many of which are weeds. Although relative abundance of species would change, the land would still be covered with scrubweeds, and the overall impact on the land would be little changed. The risk of increased environmental damage from replacement weeds is considered to be minor.

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Benefits:

Potential benefits to farming In New Zealand, it is currently often uneconomical to control established broom infestations with pesticides for commercial pastoral development. Hill country farmers have abandoned or neglected pastoral land, where woody weeds such as broom are encroaching (Popay et al. 2002). Most Regional Pest Management Strategies require farmers to control small „satellite‟ infestations and along property boundaries. Benefits would accrue if broom- covered land was substantially cleared as a result of biological control: 1. Net annual benefits from additional land being under farm production 2. Saved costs of using herbicide to prevent broom spread.

Historical data were used to estimate current control costs on farms, and New Zealand Land Resource Inventory (NZLRI) mapping information, historical papers and reports to evaluate possible benefits. The methodological details can be found in Jarvis et al. (2003) (Appendix B). Until 1985, weed control on farms was subsidised to the extent of 50% of chemical costs under the Noxious Plants Control Scheme. The total cost in 1984/85 for chemical control of broom on farms was $1.163 million ($1.605 million in 1999 dollar values). This does not include expenditure on other control techniques and may significantly underestimate control costs.

The NZLRI database provided information on the area of land with broom cover that could reasonably be developed by farmers. Carrying capacities were determined, and a net return at farm gate for controlling the broom and developing land, once clear of broom, was calculated. Development costs and land maintenance costs were assessed. A sinking fund calculation was applied to capital expenditure to allow for all costs and benefits to be expressed on an annual basis. The proportion of net benefits attributed to broom control, rather than other land development, was partitioned on the basis of the relative proportion of capital development costs represented by conventional broom control. The details of this methodology, the base data, and the detailed results can be found in Jarvis et al. (2003, Appendix B).

Total net benefits of farming land covered by broom, net of all development and operating costs, are $13.334 million per year; the benefits attributable to the biological control of broom, according to a partitioning rule (Jarvis et al. 2003, Appendix B), are $6.534 million. This is the opportunity cost of lost production because land is currently covered in broom and therefore not in productive use. Adding the annualised cost of broom control ($1.793 million) and the current estimate of broom control costs to farmers ($1.605 million) gives $9.932 million as the total net benefit to farming.

Potential benefits to forestry Broom can out-compete radiata pine seedlings in new plantations and effectively destroy the crop. This damage is overcome by spraying the broom at establishment, and then „release‟ spraying as necessary over the next 3–4 years to control competition. Seventeen major forestry companies in New Zealand grow 1 380 000 ha of exotic 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

timber, and smaller companies grow a further 492 000 ha. In 1999 the 17 major forestry companies provided data on annual expenditure for broom control. Expenditure by the smaller companies was estimated based on mean per hectare costs for the major companies. The overall annual cost of broom control was estimated then to be $1.31 million (Jarvis et al. 2003, Appendix B).

Douglas fir is a major forestry species in the South Island high country. Broom is considered the worst companion plant for Douglas fir seedlings. It competes strongly for moisture and space to the point of complete tree suppression. Douglas fir seedlings established into broom will have low survival and suppressed growth (M. Belton, pers comm.)

In paired competition of this nature, the plant that wins is the one that grows fastest. A relatively small shift in relative growth rates could reverse the competition hierarchy, and biological control could achieve this. Reduction in the competitiveness of broom might allow another scrub weed such as gorse, buddleia or pampas to overtake both broom and trees, but in many plantations, especially at higher elevations, broom is the only significant weed present.

In the drier east coast of the South Island broom competes strenuously with tree seedlings for water. Approximately 7750 ha of pines are infested by broom in this area. Watt et al. (2003, cited in Appendix B)) noted that after 2 years, juvenile P. radiata plants that were growing without broom had an above-ground biomass that was 25-fold greater than that of trees growing with broom. In trials conducted by the Forest Research Institute in Canterbury, competition with broom resulted in a loss of 2 years of growth by year 9 of the rotation (P. Clinton, pers. comm. 1999, cited in Appendix B). The long-term effects of this competition are not yet quantified, so this analysis makes the conservative assumption that a 2-year delay in harvest was the full extent of damage by broom. Assuming final production volumes of 446 m2 for radiata pine at 27 years (Ministry of Forestry 1995, cited in Appendix B) gave a reduction in net present value of $720 per hectare for a 2-year increase in rotation length to a 29-year harvest (using 4.75% real discount rate). Over the 7750 ha in East Coast South Island alone, this equates to $5.58 million over the full rotation length or, annualised, $0.207 million per year (Jarvis et al. 2003, Appendix B).

Potential monetary benefits to Government Departments, State-owned Enterprises and Crown Entities Consultation with the Department of Conservation (DOC) in 1999 (Jarvis et al. 2003, Appendix B) revealed that annual expenditure on broom control, including operational costs, was then $0.531 million. Successful biological control of broom would also reduce infestations at sites where, due to budgetary constraints, DOC does not currently practice control. The $0.531 million estimate is therefore a lower bound estimate of the value of biological control within conservation lands (non-monetary benefits to DOC are assessed in section 6.1). Jarvis et al. (2003, Appendix B) also obtained estimates of annual expenditure on broom control from Transit NZ ($0.2M) and Transpower ($30,000). 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

Land Information NZ manages invasive weeds on unoccupied Crown Lands (lands without title, mainly braided rivers, roads and marginal strips, and unoccupied pastoral lease land). LINZ provided Jarvis et al. (2003) with an estimate of $0.5 million per year for broom control on UCL (W. Chisholm, pers. comm. 1999, cited in Appendix B). As this is insufficient to treat all broom infestations, the strategy for containment is to prioritise treatment of plants in the headwaters of rivers that are a seed source for the colonisation of land downstream. We have assumed that, even with highly effective biocontrol of broom, treatment of some priority areas will continue, saving a maximum of 80% (i.e. $0.4 million), rather than 100% of the annual broom control costs. Control of broom on those sites where there is currently no control is not valued but would be an additional benefit.

Overall cost–benefit analysis: Jarvis et al. (2003, Appendix B) noted the following caveats concerning their analysis:

1. No attempt was made to estimate non-market benefits (such as improved aesthetics, or access to wilderness areas) or any second-round effects, such as added value of additional sheep meat production from farm gate to FOB.

2. Of necessity, the analysis simplified very complex spatial, temporal and climatic patterning of levels of damage to broom, effects of that damage, and levels of benefit. For example, in some places, successful biological control could increase herbicide use, reducing estimated net benefit to farmers.

3. The analysis relied on historical data. Reduced propensity to control scrubweeds, and declining farm profitability may have reduced herbicide use since then, leading to an overestimate of potential benefits

4. The analysis relied on historical data. It is likely that the area of land now covered by broom has increased in the last 30 years, leading to an underestimate of potential benefits.

5. Overton et al. (2005, cited in Jarvis et al. 2005) predicted that broom has the potential to invade approximately five times the area it presently occupies in the Manawatu region of New Zealand alone, where broom is already widespread. The potential for expansion would be significantly greater in regions, such as Northland or Fiordland, where broom is uncommon. Therefore, the greatest potential benefit of biological control may result from preventing or reducing the impacts of broom invasion over the large tracts of suitable habitat that it has not yet colonised. This benefit is not quantified here.

The annualised costs and benefits of biological control of broom are summarised in Table 3. Uncertainty regarding the likelihood of success and the extent of non-target attack to tree lucerne is addressed by assessing a range of scenarios for the long-term costs and benefits of biocontrol: failure to control broom; a 25%, 50% and a 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

95% reduction of broom. For most sectors it has been assumed that the benefits are proportional to the reduction in broom represented in the scenarios, although it is acknowledged that this is a simplification of reality. Jarvis et al. (2005, Appendix B) address this in more detail. Future costs of establishing the control agents are included. This analysis assumes the worse-case scenario where tree lucerne would receive non-target attack at least to the same degree as broom, even though tests indicate that this may not be the case (see section 6.1). The analysis also assumes that tree lucerne will be planted to its full potential of 10 000 ha, even though current plantings are probably less than 5% of that.

Finally, for beekeeping, costs associated with moving hives should not occur annually, as we have assumed, if new locations provide the bees‟ year-round requirements. Furthermore, in both the Pacific northwest of the USA and in Japan, where broom is also an invasive weed, only 3–40% of broom flowers were pollinated by a combination of honeybees and bumblebees (Parker 1997; Suzuki 2000; in Jarvis et al. 2003). If the situation is similar in New Zealand, then even a relatively large (c. 60%) reduction in flowering might not reduce pollen availability to bees, which would greatly increase the net benefit of both the 25% and the 50% control scenarios. Moreover, our analysis did not consider whether other important spring pollen sources (e.g. Taraxacum officinale, dandelion) are likely to replace broom, reducing the impact of broom control on honeybees.

The likelihood of future levels of control is very difficult to predict, and the values assigned to these scenario probabilities have a major effect on the net annual benefit calculation. The higher the probability ascribed to the more effective control scenarios, the greater the net benefit overall. Quentin Paynter (Landcare Research, pers. comm., 2005) has recently analysed the history of biological control programmes against legume trees and shrubs worldwide. He found that a high proportion of the projects conducted against weeds resembling broom have been highly successful, or are very promising. This analysis is provided in Jarvis et al. (2005) and the probabilities of the four control scenarios have been applied to the cost–benefit analysis (Table 4). The probability that a biological control programme will have no impact on broom is 0.167. In this scenario, there is an annual cost to the New Zealand economy over the life of the control programme. The probability of partial control being achieved (25–50% reduction in the effect of broom) is set at 0.083. The likelihood of complete control of gorse is set at 0.67 (Table 4).

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Table 3. Annualised costs and benefits for the control of broom under three scenarios: 25%, 50% and 95% reduction of broom (modified from Jarvis et al. 2005)

Cost & benefit ($ Million) of percentage reduction in broom Sector groups 0% 25% 50% 95%

Benefits by sector District councils 0 0.140 0.278 0.557 1 Farming (a) saved chemical control 0 0.401 0.802 1.605 1 (b) incr. farm production 0 1.096 3.753 8.327 1 Forestry (a) saved weed control 0 0.173 0.591 1.311 1 (b) incr. production SI dry zone 0 0.052 0.104 0.207 1 DOC 0 0.133 0.266 0.531 1 LINZ 0 0.100 0.200 0.400 1 Transpower 0 0.007 0.015 0.030 1 Transit New Zealand 0 0.050 0.100 0.200 1 Subtotal 0 2.152 6.109 13.168 Costs by sector Beekeepers 0 1.178 1.905 2.408 2 Forage values 0 0.225 0.337 0.450 3 Soil conservation 0 0.150 0.150 0.150 4 Subtotal 0 1.553 2.392 3.008 Establishment costs 0.027 0.027 0.027 0.027 5 Net annualised benefits (millions) -0.027 0.572 3.690 10.133 Probability of scenario 0.167 0.083 0.083 0.67 1.000 Weighted benefit -0.005 0.048 0.307 6.755 $7.106 millions Assumptions: 1 Except for Farming (b) and Forestry (a) scenarios benefits are calculated pro rata to percentage reduction in broom, assuming control at a range of sites scattered over release areas. 95% scenario approximating total broom control. 2 Based on the data from our survey for the three scenarios of 25%, 50% and 95% control of broom. 3 Assumes some forage land sprayed to control agents even at low efficacy for broom control and arbitrarily set at half the cost of spraying all land that may potentially be developed for tree lucerne. 4 Based on a switch to alternative recommended species planted for soil conservation. 5 Annualised costs for $500,000 establishment costs over 20 years at 4.75% real interest rate. 6 Probability of the three cases set to = 1.0.

Jarvis et al. (2005) prepared a discounted cashflow for this project. The assumptions are presented in Appendix B. An internal rate of return of 56% was calculated, with a net present value (NPV) of $26.13 million at a discount level of 10%, and $73.04 million at 5%.

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A sensitivity analysis based on the net annualised weighted benefit of 7.106 millions (Table 4) showed that even in a pessimistic scenario, where benefits were decreased by 20% and costs increased by 20%, the IRR remained at 48% and the NPV at 48.71 million at the 5% level (Table 6). Table 4. Sensitivity analysis of errors in estimating costs and benefits (From Jarvis et al. 2005).

(a) Internal rate of return Benefits −20% +20% −20% 51% 61% Costs +20% 48% 59%

(b) NPV ($ millions) @ 5% discount rate Benefits −20% +20% −20% $58.33 $97.37 Costs +20% $48.71 $87.75

6.5 Cultural, social, ethical and spiritual effects Assess the magnitude and distribution of any adverse and beneficial impacts on people and communities that adversely affect or maintain/enhance (in the case of beneficial impacts) their capacity to provide for their own social and cultural wellbeing both now and into the future. Also assess any ethical or spiritual risks, costs and benefits that might arise.

Community consultation: The Canterbury Broom Group is a community-based initiative originating in Canterbury. It is a Trust supported by funding or in-kind support from the NZ Landcare Trust, Department of Conservation, Environment Canterbury, Selwyn Plantation Board, Rayonier New Zealand (local forestry companies), and six foundation farmers. The formation and aims of the Group have been the subjects of press releases. The Canterbury Broom Group is funded by the MAF Sustainable Farming Fund and by contributions from collaborators within the community.

Jarvis et al. (2003) consulted widely in the preparation of the cost–benefit analysis reproduced in Appendix B. Those consulted included district councils, regional councils, Transpower, Land Information New Zealand, Transit New Zealand, beekeepers, DOC conservancies, forestry companies, and AgResearch. 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

In preparing this application, an information pack was assembled, and distributed to 82 Māori organisations (see section 6.3), Department of Conservation, Royal Forest and Bird Protection Society, Beekeepers Association of New Zealand, Federated Farmers of New Zealand, and the Nursery and Garden Industry Association. The pack is reproduced in Appendix A, along with all response received. All issues raised in the course of this pre-application consultation are addressed in this application. Personal communications from other correspondents are acknowledged in the text. Meetings were also held with ERMA NZ and Department of Conservation staff.

Risks and costs: Apart from the issues already addressed in Section 6, no additional cultural, social, ethical or spiritual risks or costs have been identified.

Benefits: Apart from the issues already addressed in Section 6, no additional cultural, social, ethical or spiritual benefits have been identified.

Ethical issues and considerations: None Identified

6.6 Other effects (including New Zealand’s international obligations) Assess any remaining adverse and beneficial effects not already covered including any effects on New Zealand‟s international obligations.

Risks and costs: No additional issues have been identified

Benefits: No additional benefits have been identified

6.7 Overall evaluation of risks, costs and benefits It is the role of the Authority to decide whether the positive effects (benefits) of the conditional release outweigh the adverse effects (risks and costs) taking into account any control(s) that may be imposed. However, if you have a view on the relative importance of the different risks, costs and benefits and how they should be brought together in the overall evaluation of your application then please state that here.

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Broom is spreading, and the costs it imposes on the New Zealand environment and economy are rising. Its distribution is limited at present, but without intervention there appears to be nothing to stop it colonising vast areas of land, especially at high elevation. It already adversely affects biodiversity values in some riverbeds, but the risk to sub-alpine and high elevation grassland ecosystems is enormous. These environmental costs heavily outweigh the environmental benefits of broom presented in sections 6.1 and 6.3. The economic costs of broom presented in section 6.4 are based on old land-use data, and as broom has expanded in range since then, these probably underestimate the true economic costs.

Ecological studies in New Zealand and Europe (e.g. Paynter et al. 2003) suggest that biological control of broom is feasible, and the analysis of successful control of similar weeds worldwide bears this out (Appendix B). Given the likely underestimate of the environmental and economic costs of broom, the range of potential gains from broom control predicted in the economic analysis is both fair and reasonable.

The most important potential risks of introducing these three species are: 1. Significant damage to non-target plants, including tree lucerne There is no evidence that any of these species will colonise native plants, and A. genistae will not attack any plant other than broom. G. olivacea and A. assimilella may attack closely-related exotic plants, some of which have economic and environmental value. With the exception of tree lucerne, the insects perform poorly on these species, and significant impact on their value in New Zealand is unlikely. I would put this paragraph after point 1. Then list point 2 and follow by remaining paragraphs.

2. Significant decreases in native forest regeneration, kererū populations and/or agricultural/apicultural potential, because of the successful suppression of broom and/or substantial non-target impacts on tree lucerne. The benefits of tree lucerne are real, but its uses are currently limited, both geographically and climatically. This application proposes that, even given the uncertainties of biological control, the potential losses from non-target attack by control agents would be heavily outweighed by potential gains from reducing the rate of spread, the density and the vigour of this serious weed.

The analyses presented in this application use the worst-case scenario, in which the utility of tree lucerne is totally compromised by the introduction of G. olivacea and A. assimilella. In fact, experimental evidence suggests that these two species perform less well on tree lucerne, and may be poor field hosts. The likely scenarios are these: 1. The insects include tree lucerne in their host range everywhere, but as it is not a preferred host, larval mortality is high, the number of adults produced is low, acceptance of alternatives as hosts is low, and larvae do not occur in damaging numbers. This is how A. assimilella and G. olivacea occur on related species in Europe, and this is the most likely outcome. 2. As 1, but where there is a lot of broom growing nearby to augment adult numbers, there could be spillover damage to tree lucerne. 3. As 1, but there is an occasional outbreak on tree lucerne that causes damage. 4. Both plants are equally acceptable as hosts. This is not as likely as 1, but if it is so, tagasaste will only be at real risk if broom is also at risk. Non-target damage sufficient to adversely affect the utility of tree lucerne in forest and bird restoration, soil stabilisation, or fodder production is likely to be coupled with more widespread, and more intense beneficial effects from control of broom. In this case, the benefits of 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

broom suppression outweigh the non-target costs. In addition, any serious adverse effects on tree lucerne could be mitigated (at a cost) by planting alternative species or by insecticidal control of the agents. This scenario is included in the cost-benefit analysis.

As with all biological control projects, the establishment of the insects in New Zealand, the level of control that might achieved, and the timeframe over which control is imposed are uncertain. Control will vary spatially, so that if control is moderately successful overall, the level of benefit is likely to be high in some places and low in others. The arbitrary scenarios presented in Table 3 generalise these uncertainties.

Section Seven – Additional Information

7.1 Do any of the organism(s) to be conditionally released need approvals under any other New Zealand legislation or is the application affected by New Zealand’s international obligations? Please indicate whether any of the organism(s) to be conditionally released are subject to other New Zealand legislative requirements e.g. Biosecurity Act 1993, Welfare Act 1999. Also indicate if the organism is subject to any international obligations e.g. CITES.

These species are not listed by CITES (http://www.cites.org/eng/resources/species.html). There are no known regulatory requirements for export from Europe. Import permits will be required under the Biosecurity Act 1993.

7.2 Have any of the organism(s) to be conditionally released been previously considered in New Zealand or elsewhere? For example, have the organism(s) been considered for import under the Plants Act? Have the organism(s) been developed as a result of a genetically modified development approval from either ERMA New Zealand or a delegated IBSC, or has it been considered by ERMA New Zealand for field testing?

None of these species has been released for the biological control of broom anywhere in the world.

Permission to release Aceria genistae in Australia was sought and granted in 2002 (approval no. N0985). No release has yet been made.

Aceria genistae and Agonopterix assimilella have not previously been proposed for introduction to New Zealand for either containment or release.

Gonioctena olivacea has been imported into the containment facility at Landcare Research, Lincoln, for evaluation since 1995 under the following MAF import permits: G95/INV/11 1997000250 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

1998003226 20030018389 2005026871. A population of this species is currently held in containment by Landcare Research at Lincoln.

An application to MAF Regulatory Authority to release Gonioctena olivacea in New Zealand was refused in 1998 (see section 3.2).

7.3 Is there any additional information that you consider relevant to this application that has not already been included?

No.

7.4 Provide a glossary of scientific and technical terms used in the application

Adventive introduced Assessment measuring impacts of biocontrol agents Abdomen hind section of an insect‟s body Biennial taking two years to develop and seed Biological control the use of one living organism to control another Bolting growing a central stem from the centre of a rosette Co-evolution where two organisms have evolved together and each influence the evolution of the other Crepuscular active at dawn and dusk Crown the centre of the rosette, the top of the root Development test how far can a larva develop before dying when fed on a test plant – as opposed to a „starvation test‟ Dorsal relating to the upper surface Ectoparasitic feeding on a host insect from the outside in

Elytra wing cases formed from one pair of wings Endemic naturally occurring in a country and nowhere else Entomophobia fear of insects 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

Epizootic parasitic on animals (including insects) from the outside or on the surface Frass larval faecal material Food web the feeding relationship between various species living together in one area, the interaction of plants, herbivores, their parasitoids, predators and diseases Frugivorous fruit-eating Gall a complex and characteristic structure grown by the plant in response to feeding by an eriophyid mite, and within which the mite lives Genus (plural Genera) a natural grouping of related species Herbivorous feeding on plants Host range the range of plants that a biocontrol agent can feed and reproduce on Host specificity testing testing to find out the host range of a potential biocontrol agent Indigenous native, but may occur elsewhere. Instar growth stage of an insect (in between moults), e.g. newly hatched = first instar Lag phase the period before a species becomes invasive in a new environment Larva(e) juvenile stage(s) of an moth Lateral relating to the side Maxillary palps appendages near the mouth Microflora microcopic plants, fungi, algae etc Microsporidian caused by a type microbe called microsporidia Monophagous Feeding on only one species of plant Monospecific only feeding on one plant species Montane relating to mountains Multivoltine having multiple generations per year Mustelid ferret, stoat or weasel Oligophagous feeding on just a few closely related species of plants Oviposit lay eggs Parasitoid an insect that feeds and develops on or within another living host insect. It completes its own development on a single host, which it kills in the process Phenology the life history of the insect and how it reacts to environmental variables such as temperature

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Photosynthesis the process by which plants harness sunlight to build carbohydrates Phytophagous plant feeding Pinnacula small bumps in the skin of a caterpillar Propagule unit of reproduction – egg, seed, fragment

Prothorax area immediately behind the caterpillar‟s head Pupa(e) stage of insect development between larva and adult Rhizobia a nitrogen-fixing bacterium Rosette juvenile plant, before the central tall flower stalk begins to grow Species a morphologically, behaviourally, or ecologically distinct group of individuals that can only breed successfully with its own kind Starvation test does a newly-hatched larva die rather than feed on a test plant – as opposed to a „development test‟ Sympatry overlapping of natural ranges Taxon (taxa) in this context, the total of species and variants of species (or more than one species) Trophic level function in the environment – photosynthesisers (plants) are a low trophic level, followed by grazers such as insects. Upper levels include predators.

7.5 List of appendices

Appendix A. Pre-application consultation Consultation document Circulation list A Risk Assessment (prepared by Ngāi Tahu) Other responses from Māori Responses from other parties Personal communications Appendix B Cost–benefit analyses and additional information Can biological control succeed against Scotch broom? How many agents are required and why haven‟t the two previously introduced species succeeded? Jarvis et al. 2003 Jarvis et al. 2005 The virtues of tree lucerne – a brief summary Broom and tree lucerne as food for kererū 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

Appendix C The host plant range of Aceria genistae as revealed by tests conducted in Europe and Australia. Appendix D The host plant range of Agonopterix assimilella as revealed by tests conducted in Europe. Appendix E The host plant range of Gonioctena olivacea as revealed by tests conducted in Europe and New Zealand.

7.6 References Please include a list of the references cited in this application form.

References marked with an * can be found in the accompanying reference volume

*Briese DT, Cullen JM 2001. The use and usefulness of mites in biological control of weeds. In: Halliday RB, Walter DE, Proctor HC, Norton RA, Colloff MJ (eds) Acarology: Proceedings of the 10th International Congress pp. 453–463. CSIRO Publishing, Melbourne, Australia.

Castagnoli M 1978. Ricerche sulle cause di deperimento e moria dello Spartium junceum L. in Italia. Eriophyes genistae (Nal.) e E. spartii (G. Can.) (Acarina, Eriophyoidea): ridescrizione, cenni di biologia e danni. Redia 61: 539–550.

*Cromroy HL 1979. Eriophyoidea in biological control of weeds. In: Rodriguez JG (ed.) Recent advances in acarology, Volume 1, pp. 473–475. Academic Press, London.

*Douglas GB, Woodfield DR, Foote AG 1998. Elite selection of tagasaste (Chamaecytisus palmensis) for drought-prone sites. Proceedings of the New Zealand Grasslands Association 1998: 181–186.

Dugdale JS 1988. Lepidoptera: annotated catalogue, and keys to family-group taxa. Fauna of New Zealand 14.

Emmet, AM 1988. A Field Guide to the Smaller British Lepidoptera, 2nd edition. The British Entomological and Natural History Society, London.

Harper MW, Langmaid JR, Emmett AM 2002. Oecophoridae. In: Emmett AM, Langmaid JR (eds) The moths and butterflies of Great Britain and Ireland Volume 4 (part 1). Harley Books, UK.

*Harris, RJ Toft RJ, Dugdale JS, Williams PA, Rees JS 2004. Insect assemblages in a native (kanuka – Kunzea ericoides) and an exotic (gorse – Ulex europaeus) shrubland. New Zealand Journal of Ecology 28: 35–47.

*HBRC 2002. Land Management. Conservation trees. Tagasaste (tree lucerne) Chamaecyctisus palmensis. Hawke‟s Bay Regional Council, Environment Topics. 2 p.

Hosking JR 1990. The feasibility of biological control of Cytisus scoparius (L.) Link. Report on overseas study tour, June-September 1990. Unpublished Report, New South Wales Department of Agriculture and Fisheries, Tamworth, Australia.

20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

*Innes J, Nugent G, Prime K, Spurr EB 2004. Responses of kukupa (Hemiphaga novaeseelandiae) and other birds to mammal pest control at Motatau, Northland. New Zealand Journal of Eecology 28: 73–81. * Jarvis PJ, Fowler SV, Syrett P, Paynter Q. 2003. Economic benefits and costs of introducing a biological control agent, Gonioctena olivacea, for broom. Landcare Research Contract Report: LC0001/034 - October 2003 (reproduced in Appendix B).

* Jarvis PJ, Fowler SV, Paynter Q, Syrett P. In review. Predicting economic benefits and costs of introducing new biological control agents for Scotch broom, Cytisus scoparius in New Zealand. submitted to Biological Control.

*Lavin M, Herendeen PS, Wojciechowski MF 2005. Evolutionary rates analysis of Leguminosae implicates a rapid diversification of lineages during the Tertiary. Systematic Botany 54: 575–594.

Lindquist EE, Sabelis MW, Bruin J (eds) 1996. World crop pests. Volume 6. Eriophyoid mites their biology, natural enemies and control. Elsevier. 790 p.

Lvovsky, A.L. (1981. Family Oecophoridae, pp. 560-638. In Medvedev, G.S. (Ed.), Keys to the insects of the European part of USSR 4: Lepidoptera part 2, 1092 pp., Leningrad (in Russian). English translation, Leiden 1990.

MAF 2001. Fencing management for surface erosion control (Chapter 3) and Fodder bank establishment (Chapter 7) http://www.mfe.govt.nz/publications/land/soil-conservation-handbook-jun01/soil-conser-b-ch1-10-jun01.pdf

*Manson DCM 1984. Fauna of New Zealand Number 5. Eriophyinae (Arachnida: Acari: Eriophyoidea). DSIR, Wellington, New Zealand.

*Manson DCM 1989. New species and records of eriophyid mites from New Zealand. New Zealand Journal of Zoology 16: 37–49.

*Martin N 2003. Is the New Zealand endemic gall mite Aceria clianthi endangered? DOC Science Internal Series 146.

Owen, SJ 1998. Department of Conservation strategic plan for managing invasive weeds. Department of Conservation, Wellington.

*Paynter Q, Jourdan M 1998. Report on weed work for USA. Unpublished CABI Bioscience report.

*Paynter Q, Downey PO, Sheppard AW 2003. Age structure and growth of the woody weed Cytisus scoparius (Scotch broom) in native and exotic habitats: implications for control. Journal of Applied Ecology 40: 470–480.

20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

Popay AJ, Rahman A, James TK 2002. Future changes in New Zealand hill country pasture weeds. New Zealand Plant Protection 55: 99–105.

Reid VA 1998. The impact of weeds on threatened plants. Department of Conservation Internal Report 164.

*Richards AW, Waloff N 1962. A study of a natural population of Phytodecta olivacea (Forster) (Coleoptera, Chrysomeloidea). Philosophical Transactions of the Royal Society of London Series B, 244: 205–251.

Shaw RH, Fowler SV 1996. Report on weed work for New Zealand, 1996. Unpublished report of the International Institute of Biological Control, Ascot UK, 1996: 29–35.

*Sheppard JS, Bulloch BT 1986. Management and uses of Chamaecytisus palmensis (tree lucerne, tagasaste). Plant Materials for Conservation Technical Notes S3: 194–198.

Sullivan JJ, Williams PA, Timmins SM in press. Secondary succession through exotic Ulex europaeus (gorse) compared with Kunzea ericoides (kanuka) near Wellington and Nelson. New Zealand Journal of Ecology.

*Syrett P 1993. The insect fauna of broom, Cytisus scoparius in New Zealand. New Zealand Entomologist 16: 75–83.

*Syrett P, Emberson RM 1997. The natural host range of beetle species feeding on broom, Cytisus scoparius (L.) Link (Fabaceae) in Southwest Europe. Biocontrol Science and Technology 7: 309–326.

Syrett P, Fowler SV, O‟Donnell DJ, Shaw RH, Smith LA 1997. Introduction of Gonioctena olivacea (Coleoptera:Chrysomelidae) into New Zealand for biological control of broom Cytisus scoparius: An importation impact assessment. Unpublished Landcare Research Report.

*Waloff N, Richards AW 1958. The biology of the chrysomelid beetle Phytodecta olivacea (Forster) (Coleoptera: Chrysomelidae). Transactions of the Royal Entomological Society of London 110: 99–116.

* Walsh RS 1978. Nectar and pollen sources for bees. National Beekeepers Association of NZ.

*Wapshere A 1974. A strategy for evaluating the safety of organisms for biological weed control. Annals of Applied Biology 77: 201–211.

*Webb CJ, Shand JE 1985. Reproductive biology of tree lucerne (Chamaecytisus palmensis, Leguminosae). New Zealand Journal of Botany 23: 597–606.

20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

Webb C, Sykes W, Garnock-Jones P 1988. Flora of New Zealand vol. 4 – Naturalised Pteridophytes, Gymnosperms and Dicotyledons. Christchurch, New Zealand: DSIR Botany Division.

*Williams PA 1981. Aspects of the ecology of broom (Cytisus scoparius) in Canterbury, New Zealand. New Zealand Journal of Botany 19:31-43.

*Williams PA 1983. Aspects Secondary vegetation succession on the Port Hills Banks Peninsula, Canterbury, New Zealand. New Zealand Journal of Botany 21: 237–247.

Section Eight - Application Summary Summarise the application in clear, simple language that is able to be understood by the general public. Include a description of the organism(s), the purpose of the conditional release, proposed controls and any associated risks, costs and benefits. Any consultation that was undertaken should be noted. This summary will be used to provide information for those people and agencies who will be notified of the application (e.g. Ministry of Agriculture and Forestry, Ministry for the Environment, Department of Conservation, Regional Councils, etc) and for members of the public who request information. Do not include any commercially sensitive information in this summary – this should be attached as a separate appendix and clearly marked “confidential”.

The Canterbury Broom Group wishes to introduce a gall-forming mite, a shoot moth, and a leaf beetle as part of the biological control programme against the weed broom. The insects will be sourced from fixed regions of Europe, and this will be a condition on the release. The application to introduce these control agents incorporates the input from wide consultation with Māori, local government, and conservation, environmental and producer organisations.

Broom seedlings aggressively invade open, bare substrates such as river gravels, forestry sites, gaps in pastures, or bare ground in native habitats. All they need is light. It has only been spreading since the 1950s, and so has a much smaller distribution than gorse, but its potential distribution is much greater. Unlike gorse, broom thrives in the cold, and can invade to high elevation, so that areas like Tongariro National Park are at serious risk from invasion by broom. It grows to about 3 m tall at 10 years of age, and forms dense stands. Broom has some positive values because it is used by bees, protects land where other shrub vegetation won‟t grow, is eaten by pigeons, and sometimes nurtures forest trees. However, it also chokes out productive pastures, overtakes new forest plantations, and out-competes native plants in fragile habitats. On balance, the costs of broom far outweigh its benefits.

There is good evidence that biological control could reduce the rate of spread of broom, and reduce its impact on New Zealand‟s environment and economy, although the level of control that might be achieved can‟t be accurately predicted. The three agents form part of a complementary suite of natural enemies designed to achieve maximum control of the weed. The detailed cost–benefit analysis contained in the application explores the economic efficiency of different levels of biological control, and concludes that it is economically desirable through the likely range of outcomes. The insects may be able to control broom, but are they safe?

The major risk posed by new insects is potential damage to desirable plants. These agents were initially selected because they have narrow host-plant ranges. Each has been the subject of experimental research to determine their 20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

host-plant range for over 10 years. There is no evidence that any of these species will colonise native plants, and A. genistae will not attack any plant other than broom. G. olivacea and A. assimilella may attack exotic plants closely related to broom, some of which have economic and environmental value. With the exception of tree lucerne, the insects perform poorly on these species, and significant impact on their value in New Zealand is unlikely. Tree lucerne is valued as a fodder for bees and for grazing animals, as a nurse crop for forest regeneration, as a soil conservation plant, and as a food source for native birds.

The application examines the environmental and economic consequences of severe non-target impact on tree lucerne, even though this is unlikely. The benefits of tree lucerne are real, but its uses are currently limited, both geographically and climatically. This application proposes that, even given the uncertainties of biological control, the potential losses from attack by control agents on tree lucerne would be heavily outweighed by potential gains from reducing the rate of spread, density, and vigour of this serious weed.

On balance, the application concludes that the benefits of introducing the three control agents outweigh any economic or environmental costs.

Checklist

Please check and complete the following before submitting your application:

All sections completed Yes Appendices enclosed Yes/ NA* Confidential information identified and enclosed separately Yes/NA Copies of additional references attached Yes/NA Cheque for initial fee enclosed (incl. GST)† Yes/No If “yes”, state amount: $………. Fee direct credited to ERMA bank account: Yes/No If „yes” give date of DC …/…/… and amount: $………. Application signed and dated Yes Electronic copy of application e-mailed to ERMA New Zealand Yes

*NA – not applicable

† The cost of processing the application will be charged to you in accordance with our pricing policy. A fees and charges schedule, including the initial fee required with the application can be found on our web site under new organism applications. Note that we will be moving to a fixed pricing policy effective from 1 December 2003 – please ask ERMA staff for further details.

20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz

Signed: Date:

20 Customhouse Quay, Cnr Waring Taylor & Customhouse Quay PO Box 131, Wellington Phone: 04-916 2426 Fax: 04-914 0433 Email: [email protected] Website: www.ermanz.govt.nz