COLUMBUS, Ohio (WTVN)--Green Columbus is lining up volunteers for a week full of Earth Day activities.

Green Columbus founder Tad Dritz says volunteer activities between April 19 and April 26 range from community gardening to tree planting to clearing away "invasive species" like honeysuckle and garlic mustard.

The theme for this year's celebration is "Gratitude", "a way of saying thanks for everything the environment provides us," Dritz says.

Columbus's Earth Day celebration is the largest volunteer effort in the United States. This year, Green Columbus is hoping to recruit 5,000 people to help.

Since 2007, volunteers have planted more than 23,000 trees around Columbus.

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