A Tale of Two Orchids
There are 26 native orchid species (family Orchidaceae) in Colorado. Native orchids often rely on specific pollinators or fungal partners, which can limit their ranges. But while many are uncommon and have specific partners, some species can be invasive and generalist. Recently, we’ve been documenting both an uncommon orchid and a potentially invasive orchid—both for conservation-related reasons.
Orchids often require a fungal partner for germination, but the coralroot orchids (genus Corallorhiza) are fascinating because they take the relationship further and remain parasitic on the fungus throughout their life. Instead of photosynthesizing, they totally rely on their fungal partner for energy. Therefore, they don’t quite look like regular plants. They lack true leaves and green coloring. They spend much of the year underground, as rootlike structures, only appearing above-ground as a flowering stalk in the spring.
In summer of 2024, our team discovered a population of striped coralroot orchid (Corallorhiza striata) at Chatfield Farms. The striped coralroot had only been collected once in Jefferson County in 1905. This past summer 2025, I discovered the second at Bear Creek Lake Park. This population is vulnerable because it is in a heavily trafficked area and there is the prospect of expanding the park’s reservoir. We worked with the park to document this population. Biodiversity documentation like this is essential for protecting vulnerable species and habitats.
Striped coralroot orchid is an uncommon native species of orchid collected only twice in Jefferson County since 1905.
Despite the rarity of most orchid species, some may be widespread and weedy. We’ve recently documented the spread of an introduced and potentially invasive orchid species, the broadleaf helleborine (Epipactis helleborine). Like other orchids, it requires an association with fungus for seeds to germinate, but it is not highly specific to single fungal species, which may be one reason it can be introduced and spread so readily. Broadleaf helleborine has green pigments and photosynthesizes, so it can obtain nutrition on its own after it germinates. This species is easily overlooked due to its small, greenish flowers that point downwards, but may be easily spread via its small, dust-like seeds. First recorded in Colorado in 1994, broadleaf helleborine has remained uncommon, until recently. Our recent collection is only the second one for Jefferson County, but iNaturalist observations indicate the species is becoming increasingly common in Colorado.
Broadleaf helleborine is an introduced, weedy species of orchid in Colorado that is becoming more common.
Learn more about native, introduced and ornamental orchids by scheduling a tour of our natural history collections.
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