The Federation of Maori Authorities says some of its members are reporting that it will take two years before their farms recover from drought.
Maori-run farms throughout the North Island have struggled to cope with extraordinary drought conditions over the past three months.
In Taranaki, the long dry spell has caused PKW - Fonterra's largest milk supplier in the region - to lose $1.5 million in revenue.
Other regions have recently had potentially drought-breaking rain but others, including Northland and Gisborne, have had little relief.
The federation's chief executive, Te Horipo Karaitiana, says members predict it could take two more summers before farming operations are back to normal.
Mr Karaitiana says he is aware that some farmers have had to sell a lot of their stock earlier, including some of their valuable breeding stock.
However, he says all farmers, including the federation's members, need to realise that adverse weather conditions are going to become more frequent.