By Rylee Osterberg, Spring Education Intern
Picture yourself walking through the Garden in early summer, basking in the beauty and colors of early summer flowers. Out of the corner of your eye, you spot an orange butterfly with black and white spots casually resting on a thistle. Although it looks like a monarch, it’s not quite the same. What could it be?
The butterfly you most likely see is a Painted Lady! Painted Ladies are a species of butterfly well known throughout most of the world. Found in nearly every area of the globe, the Painted Lady is called the cosmopolitan butterfly because it has the largest distribution of any butterfly in the world!
Painted Ladies are characterized by their orange wings with black and white spots, and are commonly called thistle butterflies because thistle is their favorite plant to feed on. In fact, its scientific name Vanessa cardui translates to “butterfly of thistle.” Painted Ladies owe their widespread abundance to the fact that they feed on such common plants like thistle, aster, cosmos and Joe-Pye weed.
Although Painted Ladies have a similar coloration to Monarchs and look strikingly similar to American Ladies, you can tell them apart by counting the spots on their hindwings. The American lady has two spots while the Painted Lady has four!
Did you know, Painted Ladies undergo their entire lifecycle (egg, larvae/caterpillar, pupa/chrysalis and adult) in less than a month? Painted Lady eggs are light green and as small as a pin tip. When hatched, a painted lady caterpillar will eat its own egg. Their caterpillars can be identified by their grayish-brown color, spikes of fur and yellow lines running down their backs.
Unlike other butterflies in the genus Vanessa, Painted Lady larvae weave nests from silk to support and protect themselves from predators and the elements. These fluffy nests can often be found on thistle plants where there is an abundance of food. Because the caterpillars cannot digest the hairy substance of the thistle leaf, it uses that and silk which it produces to create their nests on the thistle plant. With time and practice, spotting their nests can become relatively easy.
Painted Ladies are unlike other butterflies in that they are considered to be an irruptive migrant, meaning that they migrate independently of any geographic or seasonal patterns. Their migration may be partially linked to heavy rains in desert areas, and may even be linked to the El Niño climate pattern. In March of this year, California saw a massive migration of Painted Ladies due to an unusually wet winter and a super-bloom of wildflowers.
The next time you’re walking around the Garden, take a look around and see if you can identify any Painted Ladies, caterpillars or their nests. Not only are these creatures beautiful to look at, they help our ecosystems to grow and thrive. Consider planting native species such as thistle, aster and cosmos in your own garden to feed these pollinators during their migratory seasons!
Want to see Painted Ladies in action? Join us for Butterflies & Blooms this summer to see these beautiful insects and to practice your identification skills. The exhibit is open daily from 10 am-5 pm June 1 through August 31.
Hope to see more Painted Ladies in your own backyard? Join the Million Pollinator Garden Challenge and plant your own pollinator paradise with these simple garden designs. You can buy these plants at local nuseries like Stone Silo Prairie Gardens, too!