Monarch butterflies are well-known for their migration behaviors from across the United States to Mexico every year. Their population has declined in years and scientists said the butterfly population is at the lowest numbers since the time they have been tracking them.

But there is a way by which the monarch butterfly can be saved and it is easy if people come forward. The society has urged people to plant milkweed. There are numerous reasons due to which the population of orange-and-black monarchs has declined. One of the main reasons is significant decline in the number of milkweed, a species of plant on which the monarch lays its eggs.

The Audubon Society has asked residents to plant milkweed in their gardens. It also asked highway road crews and parks groundskeepers to not cut milkweed growing wild along roads and in open spaces.

Milkweed is quite essential to monarchs as it is the only plant on which the butterfly species lays eggs on. "To a butterfly, the typical suburban yard with rhododendrons, nonnative Norway spruce and lawns with nonnative grasses might as well be a movie set - there's no reality to it for them", affirmed Jeffrey Glassberg, president of the Morristown based American Butterfly Association.

In general, nurseries have two types of milkweed. The cultivated versions are asclepias tuberose that has round masses of tiny bright orange flowers and asclepias incarnate that comes with white or pink flowers.

A number of researches have been carried out and majorly, all of them suggest it is the loss of milkweed crops that has brought a decline in the population of monarch butterfly.