Pulling thistles, sowing hope

For the past few years I’ve participated in “Thistle Thursdays,” targeting a popular trail near Jackson, Wyoming. The weekly weed party was organized in 2019 by Morgan Graham, wildlife habitat specialist with the Teton County Conservation District, and it attracts more volunteers each year — 16 of us in 2023.

To slow the steady march of musk thistle, a fast-spreading weed from Eurasia, we spend Thursday morning each week bending down to tackle these interlopers. We know what we do is a drop in the bucket, but right here, along this trail, we see results.

Joining Morgan is a mixed crew: native plant enthusiasts, elk hunters, employees of non-profits and the Forest Service, plus “youngsters” in their 30s and retirees like me.

My friend Mary, nearly 80, wins the prize as the oldest and most enthusiastic of the crew. While we were waiting for a friend at a trailhead this summer, she spotted a musk thistle on a steep slope, went to her car for some gloves and signaled for me to follow. “Let’s get that one,” she said. We ended up uprooting several.

Musk thistle (Carduus nutans) is an invasive weed, and like many invasive plants, it is adaptable and vigorous, producing prolific seeds. It competes for light and nutrients with native plants. Eventually, it can replace them.

To be fair, it has positive qualities. Bees, butterflies and other pollinators are attracted to its magenta flowers, and it blooms later than many native wildflowers, extending the season for insects. Songbirds eat its seeds.

But wildlife and livestock won’t eat musk thistle because of its spines. Where it grows, grazing animals must forage more heavily on other plants, reducing their vigor, which allows musk thistle to invade ever more space.

Tackling a stand of musk thistle requires determination. All flowers and buds are removed and placed in bags or bins. The plant, a long-lived biennial, must be cut off below the base, or pulled, to prevent further blooming.

All of us volunteers are suited up in protective gear that includes heavy gloves, long sleeves and sturdy boots. The work is hard, but the hours go quickly with conversation, laughter and impromptu contests to see who can pull out the largest thistle without tools.

We talk about plant ecology in general, but one question often comes up: “What makes it a weed?” Simply put, a plant is a weed if doesn’t belong where it’s growing. But as humans, we’re inconsistent.