Mr Cooper pointed to the recent receivership of Vinoptima in Gisborne and Mahana in Nelson, and believes more receiverships will follow.
"Wine farming goes in cycles and these cycles are based on the lifetime of a generation, as Michael Cooper so rightly puts it," Mr Millton said.
"This cycle is approximately 30 years and not only in Gisborne has this occurred.
"We have seen the same rotation occur in Chablis and Beaujolais in France, Tuscany in Italy and Rioja in Spain.
"Families associated with the land need to therefore assess the requirements of succession planning very carefully."
There were 2149 hectares of land in grapes in the Gisborne region in 2009 and it has declined more and more each year since, to 1272ha this year.
The tonnage of grapes produced has declined from 23,093 tonnes in 2009 to 13,000 tonnes this year.
"I believe the decline in grape production here is mostly from the advancement of the apple and kiwifruit industries, where vineyards are being pulled to make way for seemingly more profitable commodity plantings," Millton said.
"This shows what a unique and energetic diversity the Gisborne region has to offer in terms of primary production."
'Major drivers' for winegrowing in this region
Mr Millton said the persistent and committed grape growers remained or even increased their plantings of vines, taking up the renewed interest from consumers who favoured full-flavoured chardonnay and lighter-styled red wines.
"The most important criteria is the simple fact that in Gisborne our vineyards are 'dry-farmed', thereby requiring no irrigation to supplement the vines.
"This is due mainly to the high soil moisture-holding capacity of our dirt and the 980mm of annual rainfall."
Millton said while some of the very dry and arid South Island regions had half Gisborne's annual rainfall, those regions required more than 5000mm of additional water a year just to keep the vines alive through drip irrigation and frost control.
"And they must pay for that water.
"As water becomes more valuable, the cost of growing grapes in these regions will undoubtedly increase, and the carbon footprint for these producers will increase.
"That is when Gisborne will come into its own, in my view."
Millton said what concerned him most was the price growers here received for their grapes.
"Those prices need to lift 30 percent when there are so many environmental positives that this region can offer."
He makes the point that in the EU at present there is a large move to halt the use of the herbicide glyphosate. In some regions of France, this product has now been totally banned.
"NZ winegrowers are looking towards that same direction in the next few years and that will mean that under-vine weed control will be by mechanical means only, allowing the micro-organisms to flourish.
"In that lies another reason why the future of Gisborne grapes and wines is assured.
"Our unique soils, while not cluttered with stones, make this work very achievable and cost- effective, and actually enhance the fruitfulness of the grapevines."
Millton said there were three major drivers for advanced winegrowing in this region.
"We don't need irrigation for our grapes, we have the cooling effect of a fresh sea breeze off the South Pacific Ocean which helps reduce the summer heat, and our silken clay soils provide texture and taste to wines, which taste great in their youth and can age for a time to come.
"The final key factor supporting a solid future for grape-growing and wine-making here is that land in Gisborne is very valuable because it can grow many crops.
"That is another of our strengths."
