Finding Milkweed
Monarchs use a combination of visual and chemical cues to find milkweed. Once they land on a plant, they use sensory organs on their feet and heads to identify milkweed, and probably the quality of the milkweed.

"The magic happened! Saw our first monarch of the season laying eggs on the milkweed in the back garden." May 21, 2014 Kirkwood, Missouri