Monarch butterfly pair at withered boneset leaves
Through Monarch Rx, members of the public are invited to send in observations of monarchs taking up pyrrolizidine alkaloids (PAs). Boppré hopes this will provide basic information about the diversity of plants involved and whether this behavior is performed regularly or facultatively in certain circumstances only. This image, which Maryland gardener and author Nancy Lawson took in August 2020, shows monarchs on a boneset with their proboscises extended into a withered leaf. (Photo by Nancy Lawson)