The Government is setting up four new agencies to handle responsibilities currently within the Ministry for Primary Industries.
Fisheries New Zealand, Forestry New Zealand, Biosecurity New Zealand and New Zealand Food Safety will be established by April next year at a cost of $6.8 million.
MPI will continue to exist as a host agency for the new branches.
Damien O'Connor, the minister responsible for agriculture, biosecurity and food safety, has given an assurance there will be no redundancies.
"People shouldn't be worried about losing their jobs," he said on Wednesday.
"There will be some change, with a greater focus on the tasks they are doing."
Mr O'Connor says the separate agencies are being set up to create a stronger focus on their core responsibilities.
"Our priority is to achieve greater clarity and unity of purpose for these areas," he said.
"We are seeking enhanced visibility of Government policy and regulatory activities, and clearer lines of accountability and engagement for stakeholders."
There will be a "dedicated forestry presence" in Rotorua because it's the most appropriate site.
Forestry Minister Shane Jones says the changes mark a new era.
"We have a highly motivated forestry sector in New Zealand and I'm looking forward to seeing what we can achieve in partnership over the coming years," he said.
Federated Farmers said the Government was taking a pragmatic approach.
"This course avoids wholesale disruption and preserves the ministry's status as a competent authority for trading partners and certification agencies," it said.
"We certainly didn't want to see the upheaval and expense of a total carve-up of MPI."
National's primary industries spokesman Nathan Guy said the exercise was "a wasteful and ill-conceived re-brand of MPI".
"We put these agencies together in 2011 and it's a complete waste of money to pull them apart again."