On July 21, 2016

Nymphs in the garden

By Carolyn Lorié

By mid-July, the oregano in my herb garden has grown tall and tatty, and I want nothing more than to cut it back into a tidy mound. But I don’t. Doing so would deprive the flurry of common wood nymph butterflies that swarm the plants every year. The messiness is a small price to pay for the sight of them flitting around en masse.

I have learned to expect their arrival, having witnessed it every summer, since I planted gardens around my home six years ago. At first, just one or two appear, but within days there are dozens. Soon, the oregano’s purple flowers are covered in butterflies. But this brief visit is a only a part of the story of the common wood nymph butterfly (Cercyonis pegala). What are they doing for the other eleven and a half months of the year?

Not much, it turns out. At least, not at first.

The females lay eggs in late summer or early autumn on a host plant, often purpletop tridens – a common field grass with purple spikes and sticky upper stems. The caterpillars emerge before the first frost.

Unlike  other caterpillars that feast upon hatching, wood nymphs don’t eat a single thing until spring. Their first order of business is to burrow into a clump grass where they wait out the long winter months.

How butterflies overwinter varies from species to species, explained Kent McFarland, a conservation biologist with the Vermont Center for Ecostudies. Monarchs, for example, migrating to warmer climes; other adult butterflies, such as the mourning cloak, survive the New England winters by crawling beneath tree bark and entering a stage called diapause, in which their metabolic and respiratory rates slow down. Sometimes species only exist as eggs in the winter. Still others become pupae and emerge as butterflies in the spring. McFarland said that overwintering in the caterpillar stage, as the wood nymph butterfly does, is not unusual.

In late spring, the lengthening days and warmer temperatures signal the wood nymph caterpillars to end their hibernation. Having spent their whole lives without a single meal, they emerge ready to pack on the weight. They feed mostly at night, which helps them to avoid predation. Within a few weeks, they form a chrysalis and metamorphose into butterflies by mid-summer.

Common wood nymph butterflies are brown, with two ringed eyespots on the upper wings. The lower wings also have eyespots that are smaller and vary in number. Their range is vast, from southern Canada to most of the continental United States.

Compared to monarchs or black swallowtails, they aren’t particularly stunning. When they first few arrived some years ago, I hardly noticed them. But then more came.  And then more still.

Walking through my garden at the peak of their visit is like stepping into a fairy tale. One common wood nymph butterfly may not be stunning, but dozens of them at once is magical.

By mid-August, they die. According to McFarland, the adults live only a few weeks to a month at best.

I wait until the last few stragglers disappear, before taking the cutting shears to the oregano. The herb garden looks neater, but no longer magical. Next July, it will again grow floppy and messy, and I will know that the wood nymphs are on their way.

Carolyn Lorié lives with her rescue dog and very large cat in Thetford, Vermont. The illustration for this column was drawn by Adelaide Tyrol. The Outside Story is assigned and edited by Northern Woodlands magazine: northernwoodlands.org, and sponsored by the Wellborn Ecology Fund of New Hampshire Charitable Foundation: [email protected]

Do you want to submit feedback to the editor?

Send Us An Email!

Related Posts

 What’s in a name?

June 25, 2025
There’s nothing like a talk show to spark an idea for a column. Hosts Kelly Ripa and her husband, Mark Consuelos, recently discussed how people’s first names often serve as clues to the decade in which they were born. Some names that are rarely chosen today were popular in previous decades.  The given name that…

No patch left unskied

June 25, 2025
I’m calling it.   I drove around the long way, hoping to catch one last glimpse of the patch before we actually began hiking up into The Canyon. Partly because I wanted to see what I was getting into and partly because I wanted to make sure she was still there. I honestly wasn’t sure…

Pack up your troubles

June 25, 2025
The longest day of the year has officially come and gone, which means we are now on the slow, downhill slide toward winter.  Given that the days are currently long and the temperatures are nearing their peak, my family has opted for the traditional summer beach vacation. This is nothing new since we’ve rented a…

Life in a shell: eastern box turtle

June 25, 2025
As a budding naturalist growing up in the concrete-heavy environs of Boston, I would regularly thumb through my family’s collection of nature books and daydream about the creatures within. One species I was particularly drawn to was the eastern box turtle. These charismatic terrestrial turtles have high-domed shells festooned with colorful yellow or orange markings…