The Painted Apple Moth spraying programme in the western suburbs of Auckland has generated considerable controversy. An alternative programme was evaluated at last year’s Skeptics

The Painted apple moth was first recorded in the Auckland suburb of Glendene on 5 May 1999. Subsequently, it was reported from the Auckland suburb of Mt Wellington. Since this moth species has the potential to seriously impact on New Zealand’s forestry, conservation and horticulture, an eradication attempt was launched.

Following on from a meeting in November, on 14 December 2001, the Ministry of Agriculture and Forestry received a formal “Peppering Trial Proposal against the Painted Apple Moth”.

The submission was made by the Painted Apple Moth Community Coalition (CC-PAM), supported by the Community Advisory Group, an advisory group originally convened by Maf. It was prepared by Hana Blackmore (a Green candidate in the Tamaki electorate) with the assistance of Glen Atkinson of Garuda Biodynamics, Glenys Bean, John Clearwater and Meriel Watts (a Green candidate in the Waitakere electorate).

To quote from the proposal:

“Peppering is a biodynamic method of pest control, which aims to inhibit the reproductive potential of the pest being targeted…

The theory holds that the specific preparation methods produce the negative “energy” of the pest’s reproductive force, operating on a vibrational level, not a material one. Used in the field it enters the soil and surrounding vegetation producing an “unfriendly” and inhibiting environment. It is host specific and non-toxic, and does not have a lethal effect. The method has been used commercially in New Zealand for a number of years with verifiable success.”

The proposal consisted of two trials:

Field Broadcast Trial

Proposal – that Garuda install a Field Broadcast pipe containing the biodynamic preparation of the painted apple moth on the infested Traherne Island.

“The trial will aim to produce a statistically significant reduction in the painted apple moth population on the island. [R]ecent innovative developments by Garuda allow the establishment or enhancement of the reproductive inhibiting ‘pattern’ via Field Broadcast pipes. These are simple PVC pipes with internal copper circuits that can ‘radiate’ the biodynamic preparation that is placed within it.”

Peppering Ground Spray Trial

Proposal – that Garuda conduct a peppering ground spray of the biodynamic preparation of the painted apple moth on one hectare of public land in the heavily infested zone, and that a similar control area is sprayed with water.

“The trial will aim to produce a statistically significant drop in the moth catches in the actively sprayed zone, compared to both the control site and the areas surrounding the active site.”

The Technical Advisory Group (TAG), which assessed the proposal, comprised 21 members (16 scientists, 3 operations experts, 2 local council representatives) and six observers, including a representative from the Community Advisory Group. The group was devised to provide advice and make recommendations relating to the campaign against painted apple moth, including containment, control and eradication options.

One TAG member noted the following with regard to the efficacy of peppering:

“Peppering has been used commercially, as indicated in the proposal, but the “verifiable success” must be questioned. The testimonials from growers are data-free, and relate to insects with a naturally patchy distribution over both time and space. There is no numerical data to support the efficacy of peppering.”

Concern was also expressed regarding changes to the predicted outcome of the trial. The original proposal said that the peppering would affect adult dispersal, so that they were dissuaded from entering, or encouraged to leave, the treated zone; and that it would render the F1 generation sterile. As the aim was to eradicate painted apple moth, causing adults to disperse elsewhere was not considered helpful.

The usual claims about peppering relate to deterrent action, but claims of reproductive inhibition have become more common. Ultimately (and one could suggest, as a result of discussions at the meeting), the final proposal only referred to the sterilising effect of peppering – yet no measurement of this supposed effect was incorporated in the proposal.

The claims of repellent or reproductive inhibition made by the biodynamic proponents could have led to them requiring approval under the HSNO (Hazardous Substances and New Organisms) Act or the ACVM (Agricultural Compounds and Veterinary Medicines) Act. However, such registration may have been waived due to the perception of low risk or low residue involved. Ironically, such a registration could have served to legitimise the claims made for this approach.

Further critique of the proposal concerned a number of other flaws in its approach:

“The proposal(s) focus entirely on comparing numbers of males in traps in the peppered areas with those in non-peppered areas. There is no proposal to measure any infertility, nor to target any other insect. Thus, the proposal does not address the key issues discussed and agreed to at the November 14 meeting.

“Furthermore, it is proposed to run the trial over the entire period of Foray (Btk) spraying, so any results will be compromised by a known effective treatment.

“[T]he proposal as written is technically flawed, and is not capable of demonstrating any effect of peppering on painted apple moth.”

At its 15 January 2002 meeting, the Technical Advisory Group recommended that a peppering trial be undertaken on another species where there was no eradication programme in place. On the basis of this recommendation, MAF declined to supply the proponents of the peppering trial with moths.

On reflection, I have not ceased to be amazed at how officialdom has become so PC that at a critical time in an eradication campaign, much time and money can be wasted on unproven and questionable proposals.

While peppering as a pest control method now has a profile that deserves quantitative scrutiny, an eradication campaign is not the appropriate platform on which to evaluate this biodynamic approach – certainly not without compromising our biosecurity.

Recommended Posts