More than 50 people turned up for a special planting session - timed to coincide with Earth Day (April 22) - on a patch of community land just to the west of the Ballarat Link Road.

Despite the grey, overcast conditions, people of all ages donned sturdy boots and warm clothing to place blue and red gums, paperbarks and other native varieties into the soil.

Organised by the Alfredton Rotary Club, the day was designed to highlight the environmental benefits of the little-known swamp, which attracts a rich variety of birdlife.

The Bennett family, including Freya, 8, her six year-old brother Gus, and their four-year-old sister Isabel, were among those who turned up to help.

Their father, Luke Bennett, said the children enjoyed it and that it was "good to be out in the community and doing something beneficial for the environment at the same time."

Children also wrote their names on the supporting stakes so they could check on the saplings progress as they grow.

The rotary group want to ensure that the Mullawallah Wetlands - previously known as Winter Swamp - is appreciated by locals and future generations, and protected from the extensive development in the area over the next few years.

The tree-planting day was the brainchild of David Sanders, who said he was delighted with the turn-out after the City of Ballarat Council gave the group permission to plant 500 trees.

"This will be the middle of town in about 50 years' time with the growth," he said. "We would like to think that this area could become a rotary park for the community, and an entrance into the swamp."

Roger Thomas, who is The Courier's Nature Notes columnist said the wetlands were an important but little known natural reserve for Ballarat and said the trees would help shield the area from the Link Road traffic.

He also said the swamp was a great spot for ornithologists and hoped the work would help highlight an important ecosystem, which includes the visiting brolga crane as well the endangered growling grass frog.

"There are more than 100 different types of birds here," Mr Thomas said. "It's a significant wetland locally, although it's not all that well known."

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