A Pennsylvania butterfly farmer says listing the monarch as a threatened species could do more harm than good.

In my area (the upper Midwest), monarch caterpillars occur almost exclusively on Asclepias syriaca, also known as the common milkweed. With its broad, oval leaves and round clusters of pale purple ...

Monarch caterpillars eat 200 times their weight in milkweed and can devour a whole leaf in less than 5 minutes. Monarch butterflies are poisonous to predators because of the chemicals in the milkweed ...

A Pennsylvania butterfly farmer says listing the monarch as a threatened species could do more harm than good.

The natural phenomenon of the iconic monarch butterflies migrating south for the winter is a fascinating one - and it's one ...

common milkweed, where females lay their eggs, and which serves as a major source of food for the camp's population of monarch caterpillars. The researchers wanted to know whether any phenological ...

Testing by the Xerces Society and the University of Nevada-Reno found that milkweed leaves, the main food source for the monarch caterpillar, were contaminated by 64 pesticides. One of these ...

People and farmers could continue to remove milkweed, a key food source for monarch caterpillars, from their gardens, backyards and fields but would be prohibited from making changes to the land ...

when she first spotted their caterpillars at her home in Pigeon Forge, Tennessee, munching milkweed. She was fascinated and contacted Monarch Watch, a program based at the University of Kansas ...