Otago Fish & Game officer Nigel Pacey said the mass planting took place annually — using local business volunteers — to maintain the wetland which was converted from farmland five to six years ago.
"It was farmland that was unproductive so Fish & Game got a hold of the land — about 40ha — and converted it to wetland.
"Now we are just trying to turn the paddock back into natives."
The planting provided habitat for native species, as well as game birds, he said.
There were also a couple of mai mai in the wetland that were opened to junior shooters during duck-shooting season.
The team of about 15 people began planting the trees, supplied by Trees that Count, at 9am and were "done and dusted" at 3pm, Mr Pacey said.
"We got them in faster than we thought we would. We thought we would be out there all day."
