An army of chainsaws took down about 50 casuarina trees over the weekend at the Alfred Blackburn Smith Nature Reserve on the South Shore.

Horsfield Landscaping donated its services to remove the trees, at the request of the Bermuda Audubon Society — the group responsible for maintaining the open space.

Audubon president Jennifer Gray said she was “absolutely thrilled”.

The Audubon Society was desperate to get the casuarina trees removed because they are considered an invasive species.

They are typically found near the shore and can sink their roots into any limestone foreshore and accelerate cliff erosion.

“And that’s one of our biggest threats on the Island, cliff erosion and sea level rise,” Ms Gray said. “In today’s world the arrival of invasive species happens a lot faster than we can respond to them.”

The casuarina is also a threat to other plants and is sometimes an obstacle to the re-emergence of the Bermuda cedar tree.

Horsfield Landscaping spent five hours removing the trees, just west of the Coral Beach Tennis Club in Warwick. They took down casuarinas as tall as 30-feet.

The work would have cost as much as $2,500 if the Audubon Society was a paying customer.

Owner Kevin Horsfield said: “It was our company day of giving.

“ This year we decided to give our time and effort to the Audubon Society.”

The Horsfield crew has also done charity work with properties owned by the Bermuda National Trust.

Eventually the Audubon Society plans to replace the chopped casuarinas with endemic species like Bermuda cedar.