Secret crop of near-extinct Oaklands donkey orchids discovered in the Riverina

The Oaklands donkey orchid is near extinction. (Supplied: Murray Local Land Services)

Rangers have discovered a secret meadow of near-extinct native orchids on a travelling stock reserve in the Riverina.

The extremely rare Oaklands donkey orchid comes from the genus Diuris, known for its petals that poke up like "donkey ears".

Until recently, there were just 1,000 Oaklands donkey orchids remaining, their survival threatened by livestock grazing, rabbits and invasive weeds.

Murray Local Land Services officers had been searching for a reintroduction site for the endangered bloom when they discovered a hidden crop.

"We found a single plant back in 2017," senior land services officer Shanna Rogers said.

"It was dry conditions for the next two years, and nothing came up.

Rangers discovered a new crop of the native Oaklands donkey orchid in a reserve. (Supplied: Murray Local Land Services)

Wild Orchids Project brings new life

There are just four populations of the orchid in the entire region, all clustered around Urana and Oaklands.

Ms Rogers said it was a bit of an estimate as to how many flowers there were.

"Not all of the orchids found within an area flower each year," she said.

Travelling stock reserves ranger Roger Harris on the grazing land where the orchids were discovered. (Supplied: Murray Local Land Services)

It was the incredible rarity of these flowers that seeded the Wild Orchids Project, a New South Wales Environmental Trust-funded initiative.

As part of the project, experts are looking into three endangered orchid species, also including the sandhill spider orchid and crimson spider orchid.

"Monitoring back in 2014 indicated the numbers of these orchids were incredibly low, and that we needed to do something to manage the remnant populations and boost their numbers in the wild," Ms Rogers said.

Steps to protect near-extinct orchid

Officers have started caring for known remnant populations and are working to reintroduce orchids back into the wild at new translocation sites.

In the wake of their latest discovery, officers have fenced off the meadow to protect the orchids from grazing stock.

It's just a small patch – 3 hectares of a 150-hectare reserve.

But it could determine the survival of this highly endangered plant.

"While the orchids are dormant tubers, it's not a risk," Ms Rogers said.

"But we obviously didn't want to have stock grazing and trampling the orchids while they were flowering and setting seeds.

"This management of the orchids will continue permanently."