High in the mountains of central Mexico, oyamel forests are the overwintering home of the eastern migratory monarch butterflies. These pollinators migrate from Canada and the US to overwinter in Mexico’s Monarch Butterfly Biosphere Reserve. As spring arrives, they start their migration back north, seeking out milkweed to lay their eggs and nectar plants to eat.

Milkweed is essential to the monarch: It is the only plant on which they lay their eggs and the only source of food for baby monarch caterpillars. But the increased use of herbicides in agricultural expansion and the paving over of land for urban growth have destroyed millions of acres of milkweed—so much so that the migratory monarchs are now classified as endangered.

Join the monarchs’ migration journey and help these amazing butterflies—and other pollinators—by planting nectar plants and the right species of milkweed in your own backyard.