The nor-west is still free from a virulent kiwifruit vine killer.
But growers say they can't rule out the spread of PSA-V while preparing for this year's harvest.
Kumeu kiwifruit orchardist Fiona McRae says harvesting in April and May is a busy time for the industry. It requires quick turnarounds in picking bins, tractors, truck and other equipment.
"It is also a time of risk for spread of PSA."
The nor-west has a mixture of green and gold kiwifruit, and some of the vines were planted in the 1970s.
This year's dry summer has helped limit the spread of the disease, but its progression will start again when autumn arrives, because the bacteria thrive in cool and wet weather conditions.
It can also spread long distance through infected plant material and contaminated orchard equipment.
So far the 27 nor-west orchards, six of which are owner-operated enterprises, are disease-free.
Unfortunately, the disease is rampant in important growing kiwifruit areas like the Bay of Plenty, where it was first identified in 2010.
To date 69 per cent of New Zealand's kiwifruit producing hectares are on an orchard identified as having PSA-V.
Kiwifruit retail prices are likely to rise up to 20 per cent after the loss of a big chunk of this year's harvest.
Growers are learning to manage their orchards and picking up lessons from apple and grape growers about living with killer diseases.
Kiwifruit Vine Health has developed a proposed national pest management plan to protect disease-free regions like the nor-west from PSA-V.
It involves a collective approach with growers and associated industries such as beekeepers, pollen providers, nurseries and regional councils.
Growers are also increasing concerned about unmanaged and abandoned orchards, which the plan has been developed to control.
Primary Industries Minister David Carter has declared the outbreak a medium-scale biosecurity event.
There will be continuing support from the government to help affected kiwifruit growers after an initial $25 million dollar-for-dollar partnership with the industry.
- Norwest News
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