Wildflowers and weeds: Toadflax

By Shauna Dobbie

Bumblebees (above), bog fritillaries (below) and gorgone checkerspots (second below) all feed on yellow toadflax.

This lovely little flower looks just like small yellow snapdragons and it blooms through the summer across Canada. It is extraordinarily hardy, surviving to the 65th parallel north. If you’re a farmer, you might not like it, though, and it’s considered invasive in Alberta.

Linaria vulgaris is the Latin name for the plant. It hales from central Asia and Europe, including the British Isles, being one of the first plants to crop up when an area is disturbed. You’ll often find it on roadsides and on tilled land. It’s been found in Canada at least since 1820.

Toadflax probably came to Canada through cultivation, since it has been used medicinally throughout history. It has been used as a diuretic in treating dropsy (an oldfashioned name for edema). Modern studies show that it mainly affects the liver and it has strong laxative abilities. This makes sense because, apparently, it is a little bit toxic. Still, the juice of the plant is used as a remedy for inflamed eyes. You can also get a yellow dye from it.

The creatures who most appreciate toadflax are the insects who use it for food. Native insects who enjoy toadflax include the gorgone checkerspot and the bog fritillary, two pretty little butterflies. They are not obligate feeders, though, and are probably attracted to the yellow flowers. Bumblebees are also devotees.

Perhaps the most interesting thing about toadflax is the number of aliases it goes by. In different areas it is known as: brideweed, bridewort, butter and eggs, butter haycocks, bread and butter, bunny haycocks, bunny mouths, calf’s snout, continental weed, dead men’s bones, devil’s flax, devil’s flower, doggies, dragon bushes, eggs and bacon, false flax, fluellen, gallweed, gallwart, impudent lawyer, lion’s mouth, North American ramsted, rabbit flower, rancid, ransted, wild flax, wild snapdragon and yellow rod.

When I hear alternative names for the flowers, I always think of using them while driving down the highway: “Pull over, Mother! I see a nice stand of impudent lawyers!”

Toadflax.