A young farm worker trapped in a feed-out machine on a Mid Canterbury farm for more than an hour has been flown to hospital with serious injuries.

Emergency services were called to the rural property at Staveley, 40km northwest of Ashburton, just before midday.

A spokesperson for Fire and Emergency New Zealand said they are on the scene, helping police and St John.

Photographs from the scene show two fire trucks, several St John vehicles, police, and the Westpac Rescue Helicopter at the farm.

They are understood to be working to help free a person who appears to have become stuck in the feed-out machine being towed by a tractor.

St John said they were alerted at 11.53am and sent a helicopter, an ambulance and one first response unit.

A rescue helicopter has arrived alongside fire, St John, and police at the rural scene. Photo / George Heard

The worker spent more than an hour trapped in the machine.

After they were extricated, they were flown to Christchurch Hospital by rescue helicopter.

St John said they were in a serious condition.

WorkSafe says it has been notified and is making initial enquiries.

The latest provisional injury statistics from Stats NZ, released today, show there were 222,300 work-related claims made in 2022 – down 5200 from 2021.

In the agricultural sector, there were 20,700 workplace injuries last year.

In 2022, there were 22,299 workplace injuries reported in the agriculture, forestry and fishing industries - the lowest since the data began in 2009.