Northland police returned to aerial cannabis operations over the summer, despite ongoing criticism from medicinal cannabis advocates.
Just over a third of more than 34,000 plants seized or destroyed nationally in the police aerial cannabis operation this year were in Northland.
Northland police discovered 11,561 plants and seized $4360 in cash and 18 firearms as part of the operation.
Aerial cannabis operations were only carried out by Northland, Waikato, Central, Tasman and Southern districts, with some also undertaken by the Financial Crime Group.
Individual district commanders were given the choice of whether to conduct aerial cannabis operations, after the nationwide operation was scrapped in 2021.
Medicinal cannabis advocate Pearl Schomburg described the operations as a waste of money and devastating to the "green fairies" who grow medicinal cannabis.
"It's pretty ludicrous when actually cannabis is legal on prescription but illegal if you take it into your own hands and grow your own plant and make your own medicine from it."
Doctors are also extremely hesitant to write prescriptions for medical cannabis, Schomburg said, and prescription cannabis all has to be imported at high prices.
One Northland green fairy, known as Gandalf, had a whole crop sprayed and destroyed in 2019, she said.
"It was a really important crop for patients in our community - it was a low THC high CBD Indica that was desperately needed for our seizure patients.
"That could have literally ended people's lives because of a lack of that particular strain."
Schomburg said she heard of an incident over the last season where a young couple growing three medicinal plants 50 yards from their home had plants sprayed.
"Rather than the police send in a car to confiscate those plants, they sprayed them (with weedkiller) with a helicopter and terrified those two people.
"Both had multiple auto-immune conditions, one of them was just recovering from chemotherapy for cancer.
"You can imagine the devastation of spraying that awful stuff in the vicinity of healthy folk, let alone sick folk."
Schomburg said it was time people were allowed to grow a small supply of medicinal cannabis for themselves.
"It's time the Government just let us all grow a few plants each, I'm going to say three."
Green MP Chloe Swarbrick has criticised the aerial cannabis operation heavily, suggesting it was a poor allocation of resources, particularly when medicinal growers were targeted.
"With the police arguing consistently that they're under-resourced and short-staffed, I can't imagine a less important thing for them to do than flying around in choppers to cut off someone's medicinal cannabis supply," Swarbrick wrote on social media.
The director of the National Organised Crime Group, Detective Superintendent Greg Williams, said the operation was aimed at large-scale growing by gangs.
"The aim of the operation was squarely on commercial-scale cannabis growing and the organised crime groups behind them," Williams said.
"This was not about personal cannabis use or low-level offending."
Police also seized four kilograms of amphetamine and 19 grams of methamphetamine across the country during the operation.
"Police will continue to focus on the distributors of more harmful drugs, such as methamphetamine and synthetics," Williams said.
"But it is important that we continue to put pressure on those who profit from running any commercial illicit drug operations."
In Northland, just 12 offenders were spoken to by police out of 81 nationally.
Many warnings were issued for cultivation of small-scale plots across the country, police said.
Northland had only the second-highest number of plants seized or destroyed, with 13,873 found in Waikato.
Comment was requested from Northland Police, but no response was received by publication time.