Yellow Butterflies and Sicklepod Weed

This morning, a patch of weeds and wildflowers on the edge of an old field fluttered under a cloud of sunny-yellow butterflies.

Most of the butterflies appeared to be Sleepy Orange and Cloudless Sulphurs. The Sleepy Orange – small, yellow-orange butterflies with wings bordered in black – were very fluttery and almost constantly in motion. I don’t know how they got their name, but in flight they look the opposite of sleepy. The Cloudless Sulphurs – larger and pale lemon-yellow – are known as fast fliers, too, but to me they seem to have a more airy, floating quality to their flight. There also were a few scattered Gulf Fritillaries, with burning orange wings and gleaming silver spots on the under sides, and small, less bright Fiery Skippers. 

The main attraction for the butterflies seemed to be the yellow flowers of a relatively low-growing plant with lush, smooth-edged leaves, a legume called sicklepod weed (Senna obtusivolia). The common name comes from long, sickle-shaped seed pods that develop from each flower after it matures – lots of these slender, curving green pods hung in arcs among the plants. It’s not surprising to know that sicklepod weed is generally considered invasive and a serious agricultural pest. But it’s also a host plant for sulphur butterflies, and perhaps for others.

Mixed in with the sicklepod weed were a tangle of other wild plants – thick, rough grasses and pale-brown foxtails; purple morning glories and tiny, bright red morning glories; a few dandelions, the vines and showy purple flowers of maypops; some tall-stemmed yellow-blooming and white-blooming flowers I couldn’t name; a hairy vine with furry, heart-shaped leaves and small purple flowers in clusters; and prickly, purple-flowering horse nettle – and more. Along with the sicklepod weed, the small red morning glories seemed to be especially attractive to the butterflies.

This small, colorful gathering of butterflies along a roadside would have been a common sight here a few years ago. But this summer, in a season when we’ve seen so very few butterflies and moths here in and around our neighborhood, it felt like a magical spot.

Leave a Reply