The leaves of the milkweed plant are the only place that monarchs lay their eggs and the only food that monarch butterfly caterpillars will eat. (Marina von Stackelberg)

Science North in Sudbury is encouraging a weed to grow on its property.

Staff members are leaving common milkweed alone in an attempt to attract monarch butterflies. 

That's because monarchs are in trouble. Over the winter, the monarch butterfly population wintering in Mexico fell to its lowest level ever recorded.

A recent study from the University of Guelph found the main reason for the butterfly's decline is the loss of its main food source: milkweed.

Reporter Marina von Stackelberg went out with Science North scientist Dan Chaput to find out moreā€”and to try to find some monarchs.