Dear Wood Folk,
Lately, we’ve been covering a lot of overwintering butterflies, but this month’s sulphurs (colias spp.) are migrators. We have three species around Haliburton, Ontario, noted on iNaturalist. The clouded sulphur (c. philodice) is the species you are vastly more likely to see. It’s followed by the orange “alfalfa butterfly” (c. eurytheme) who originated out west, then followed the alfalfa crops to the east. And a rare native here is pink-edged (c. interior). All the species technically have “pink edges”. Their differences come down to fine details.

A couple other species are listed on iNaturalist, but may be misidentifications. That or they rode here in some cargo from Europe or Central America. Also, hybridization is common.
Orange and Clouded Sulphur Plant Allies

Showy tick-trefoil (desmodium canadense) and native lupine host sulphur caterpillars. The caterpillars will also feed on common naturalized nonnatives like clover, alfalfa, and white sweet clover. All the above are in the pea family.
The green striped cats, as often the case, feed at night. Sometimes they cannibalize each other. I haven’t heard that about any other species of butterfly yet..
I usually find these sulphurs in meadows and down muddy trails, puddling in the dirt. I have yet to see more than two at once here, but it’s possible.
The adults nectar on many of the usual butterfly attractions like milkweed and coneflower. They are not picky eaters.
Pink-edged Sulphur Plant Allies
You may spot a pink-edged in early summer, but they are rare. I have yet to see one around Haliburton.
Pink-edged have different host preferences than our title peas. They prefer blueberry plants, and others in the greater heath (ericaceae) family, which includes our blueberries and cranberries. The heath family also includes native wintergreens which can be planted rather easily, and wet loving leatherleaf and bog Labrador tea.
The pink-edged adults have a liking for the nectar of bristly sarsaparilla.

These are such pretty little butterflies and they have let me get closer with my camera than most other species. They’re a beautiful reason to plant some showy tick-trefoil (desmodium canadense) in your butterfly garden.
August 17th brings a new chapter to the Wood Folk Diaries. Specifically, The Wood Folk Diaries: Volume 4 (Poisonous Plants), Chapter 1: Bittersweet Nightshade. I’m excited to post about poisonous plants for a change!