Thousands of ladybugs released in Mall of America (VIDEO)

Managers at the Mall of America in Bloomington, Minn., released 72,000 ladybugs into the enclosed shopping center this week to protect the mall’s plants, Discovery News reported.

The mall’s 30,000 live plants, including 400 or so trees, are regularly feasted upon by aphids. Rather than using pesticides to control the problem, the mall is deploying ladybugs, which eat aphids.

The mall, the largest in the United States at 4.2 million square feet, has embraced other green initiatives, too, including converting its restaurants’ fryer fat into 600,000 pounds of bio-diesel fuel, used to power Mall of America security vehicles.

The mall also uses passive heating – drawn from 1.2 miles of skylights, light fixtures and shoppers’ body heat – to keep its building warm during arctic Minnesota winters.

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