DEAR News Of The Area,

RAEWYN Macky’s recent letter in NOTA was interesting.

I have no knowledge of blueberry growing, but I have farmed macadamias, avocados and lychees here in Boambee for 47 years and used plenty of Dimethoate over that time.

I was also party to a number of chemical trials that were carried out in this area.

Raewyn makes a number of claims as to what dimethoate may cause.

She says it is considered carcinogenic, it may cause genetic changes, and may damage a developing foetus, but provides no verifiable evidence to support her claims.

She also espoused the benefits of bait spraying for Queensland fruit fly (QFF).

It does have some effect on QFF but she is sadly misguided if she believes that bait spraying has controlled QFF in the Murray or in North Qld.

QFF made it into the Murray River valley some 20 years ago at Albury.

In that 20 years it has acclimated to colder weather, and steadily expanded its range down to somewhere near Robinvale, depending on who you believe.

So bait spraying is a tool not an answer.

As for integrated pest management (IPM), it also has some benefit in controlling insect invasion, but the Mid North Coast is the southernmost limit of predatory insects’ ability to winter over.

So in most years they die out and you have to start again.

I trialled IPM at huge cost (around $8000 a year) on this farm for three years but was unable to obtain a significant benefit.

IPM really is only successful where there is no native scrub or home gardens around that harbour pests.

Dimethoate is used in the lychee industry to control Erinose mite before flowering and after harvest when the trees begin to flush.

It is not used on the fruit.

The only alternative is Wettable Sulphur which is only partly effective.

There are viable alternatives in the Australian Pesticides and Veterinary Management Authorities (APVMA) pipeline but they can take up to twelve years to approve a new chemical, even though all the necessary trials have been done in other countries.

Regards,
Ted KNOBLOCK,
Boambee.