If you missed the green gentian superbloom earlier this summer, there’s another leafy plant experiencing a rare flowering event across Colorado’s high country right now. And this one is intriguing not only because itap pretty, but also because of its uncanny history.
Veratrum californicum, more commonly known as the corn lily, is a tall, stalky plant with wide green leaves that grows in alpine areas between roughly 8,000 and 11,500 feet in elevation. When it blooms, the main stalk grows extra length and produces hundreds of little white flowers. It’s common for the plant to reach several feet tall.
Though visually stunning, the corn lily is toxic to animals and also unattractive to many traditional pollinators, said David Inouye, principal investigator at the Rocky Mountain Biological Laboratory in Gothic. The plantap toxicity is so legendary, in fact, that what happens when animals ingest it sounds like something out of a science fiction novel.
Corn lily leaves contain a chemical called cyclopamine, so named because researchers found it to be the culprit behind certain birth defects in lambs, including those born with one eye in the center of their skull.
Scientists with the U.S. Department of Agriculture , after ranchers in Idaho reported some of their ewes gave birth to lambs with just one eye. They traced it to the pregnant sheep eating wild corn lilies, though it would take several more decades for someone to discover to produce this defect and others like skull malformation and cleft palate.
Beyond the lore, Inouye said corn lily blooms may become increasingly rare as climate change continues to warm Colorado’s high country. The plant does not flower in a regular cadence and instead responds to environmental queues that trigger the plant to invest its energy making flowers instead of additional leaves, he said. The last two significant blooming events were in 2021 and 2017, and Inouye notes there have only been eight total since he began studying them in 1984.
The theory is that when Colorado’s alpine terrain experiences a colder than average summer, the lilies will flower two years later. In addition to dropping seeds, when corn lilies bloom, they grow new roots and effectively reproduce by creating clones. Inouye said more research is needed to confirm the environmental factors that lead to flowering, but if they need cooler temperatures, the effects on future proliferation could be severe.
“One implication we can draw from that is if it takes a below average temperature summer to trigger that flowering, then as the climate warms, the flowering is going to become less and less common,” he said — all the more reason to catch them while you can.
Right now, corn lilies are blooming sporadically throughout the state, so Inouye wouldn’t go as far to call the event a “superbloom.” Even so, the flowers likely won’t last long since hot and dry conditions caused wildflowers to bloom early this year. So keep your eyes — or just one — peeled to enjoy them as you hike through the high country.
