Bittercress and Butterflies

Table of Contents

In early 2023 I was dropping off our van at our mechanic. Right down the street from him, there was an entire yard full of these beautiful little clusters of white flowers — hundreds of plants in full bloom.

I stopped to get some photos and of course added them to iNaturalist, and here was this new name I’d never heard before: Bulbous Bittercress (Cardamine bulbosa). What a good name for this plant putting out little bulbs of white blooms everywhere I looked.

A hand holds a bulb of small white flowers My first good look at this beautiful little plant.
Hundreds of small plants in bloom, filling a yard with thousands of  small white flowers The field full of Bulbous Cress. So many blooms!

A resident expert on iNat - @annieliveoak - soon confirmed the ID and let me know that it was a host plant for butterfly with another intriguing new name: Falcate orangetip. A gorgeous little white butterfly with hunter’s orange tips to their wings.

In the days after, I was driving up our long driveway back home and happened to spot these newly familiar blooms growing just feet from the gravel: a healthy little patch in the farthest northeastern corner of the western woods as it butts up against the neighbors. What a nice surprise! But as far as I could tell, no butterflies. The flowers went on their way for the year and I looked forward to trying again.

A few small plants with clusters of small white flowers and round dark green leaves grows up on the forest floor A thriving bit of Bulbous Cress near our house. It really seemed well-established in the little patch.

A year later, in late February, I was on a bird walk at the Greenwell Springs Hospital site, when a fellow birder called out a Falcate orangetip going by a few feet from us. Aha! It was much smaller than I was expecting, and so fast you could barely see the orange unless it came by pretty closely. Now I knew what to look for when the Bittercress came out again in the following days.

The next day, in the Old Pond Meadow, I was looking for some of the first dragonflies of the year (since we'd seen some while birding the day before), and there it was — a tiny little white butterfly flittering just over the top of the little flowers in the meadow, circling the meadow again and again.

I started snapping photos furiously, as it never stopped to land; I wondered what would bring it to investigate this meadow and remembered it was full of Caradmine of a different sort — much smaller and less impressive, but plentiful and apparently sharing some of the same qualities the more ostentatious Bulbous Bittercress.

A blurry photo of a small mostly-white butterfly with orange tips on its wings flying by from right to left. The outside of its hindwing is pattern in gray and white My first decent-ish photo of a Falcate Orangetip, flying by in the Old Pond Meadow

I soon spotted one or two more flying nearby and that was enough. I nearly ran over to the patch of bulbosa and soon found two or three flowering plants and at least five little orangetips perusing the area! I was treated to the sight of three of them chasing each other near one plant, and was thrilled when one flashed right in front of my lens as I was taking a photo of the cress.

A photo of a cluster of white flowers, with a small white butterfly with orange tips on its wings flying in front of it, captured blurrily A male Falcate Orangetip flashes by a the flowers just as I was snapping a photo

I reported the butterflies and bittercress to iNaturalist and to my local Wild Ones chapter to share the interaction and presence of the relatively rare plant somewhere where I had access to it. They were excited, and my friend and chapter president Janine asked to come and collect a few plants to hopefully try to get some seed for future propagation of a wonderful native and hopefully holding on to these beautiful little butterflies.

She came and gathered a few plants, and one for me as well to transplant to the Old Pond Meadow and hopefully establish a little population back there as well. We saw the Orangetips using the smaller bittercress, which I observed separately throughout that week as well, and we both went away thrilled with witnessing these little interactions that mean so much to us.

A hand holding a small potted plant

My little plant bloomed, and I even saw an orangetip near it one day (though not on it). Today, I realized the blooms had completely fallen off, or seemed to be completely gone, and much to my surprise there was a tiny, green caterpillar hanging on to the end of the stem. Some quick searching confirmed there was a pretty good chance it's a Falcate orangetip caterpillar, and this little plant is doing exactly what we were hoping it would.

I was going to try to protect and raise the little friend as best as I can, with the advice from Janine who does this sort of thing regularly, but seeing as it should spend most of the year as a chrysalis, I brought it to one of the bigger plants out in the patch and hope it can do its thing naturally.

This sort of story is the goal of conservation and naturalist work, in a lot of ways. Learning about the entire ecosystem, these relationships across the kingdoms and food cycle, and how taking a little extra interest in something that catches your eye can lead to a naturalist adventure that brings excitement and beauty into the lives of more people around you

A tiny green caterpillar, as long as a fingertip is wide, with a white stripe down the side of its body, nibbles on the small green stalk of a plant My little caterpillar friend.