Southwest Colorado Wildflowers, Collomia

Collomia grandiflora and Collomia linearis are delicate annuals very similar in height, shape, and flower structure, but two characteristics quickly separate them: the corolla of C. grandiflora is 15-30 mm long and white/yellow to salmon/orange whereas the corolla of C. linearis is 8-15 mm long and pink/violet.

C. grandiflora is, as the map below indicates, a rare find in the Four Corners region, for it is primarily a species found from western Utah to the Pacific. C. linearis, on the other hand, is a very common plant in the foothills and mountains of the Four Corners region and throughout the West.

Thomas Nuttall, famed 19th century explorer, plant collector, and Harvard teacher, named the Collomia genus in 1818 from a specimen he collected in 1811 "near the banks of the Missouri, about the confluence of the Shian River, and in the vicinity of the Arikaree village". (Nuttall as quoted in Intermountain Flora). Nuttall named the new species Collomia linearis and he described it in his 1818 Genera of North American Plants. (Click the title to read.) There is, however, a collection of this species in the Philadelphia Herbarium by Meriwether Lewis from April 17, 1806. James Reveal et al. indicate, "It is somewhat surprising that Pursh failed to describe this new genus and species or at least mention the plant somewhere in his Flora. Perhaps he ... was unable to diagnose the... specimen". Click to read more about why Lewis' collection is not considered the type.

"Collomia", from the Greek "colla", meaning "glue", refers to the sticky seeds.

Collomia grandiflora

Collomia grandiflora (Large-flowered Collomia)
Polemoniaceae (Phlox Family)

Foothills. Woodlands, openings. Early summer.
Above and left: Mesa Verde National Park, Geologic Overlook, June 9, 2016.

Collomia grandiflora grows to about 20 inches tall but as shown here is about 8 inches tall. Leaves are lanceolate, elliptic, oblanceolate, or even linear and usually stand out stiffly from the main stem which is unbranched.

Collomia grandiflora flowers have elongated pale yellow to pale salmon/orange tubes and flared lobes that are most often white. Flowers are in a dense terminal grouping interspersed among green, tiny leaf-like bracts. You can see tiny dots of gleaming glandular hairs along the flora tube and in the head of flowers.

This delicate member of the Phlox family has a small, disjunct, and rare population in Colorado, is not found in New Mexico, and is common in western Utah and Arizona and other states to the west and north. (See the range map below.)

Collomia grandiflora is difficult to find, not only because of its scarcity in the Four Corners region, but also because of its slender structure and preference for shady areas among other plants.

David Douglas, of Douglas Fir fame, first collected seeds from this plant "in the country bordering on the river Columbia" in 1828. (Douglas' words as quoted in Intermountain Flora.) Douglas named the plant and must have used the word "grandiflora" (meaning, of course, "large flower") as a relative term, i.e., this species, the second in the genus, has a flower tube 15-30 mm long, larger than the 8-15 mm long tube of the first species in the genus, Collomia linearis.

I first photographed this species with a point and shoot film camera at the Geologic Overlook at Mesa Verde National Park, June 5, 2001. I then had to scan the photograph into Photoshop and the result was poor. Over the next 15 years I visited the Geologic Overlook a number of times looking for the plant and hoping to get better photographs. In 2016 I finally succeeded.

Collomia grandiflora

Collomia linearis (Linear-leaf Collomia)
Polemoniaceae (Phlox Family)

Foothills, montane. Woodlands, meadows, openings. Spring, summer.
Priest Gulch Trail, June 29, 2005.

This cute beauty grows four-to-twenty-four inches tall in small and large groupings in meadows and in Sagebrush, Oak brush, Aspen, and Spruce woodlands. Its flowers are trumpet-shaped, about a half inch long and a quarter inch wide at the far end. Stems are reddish and leaves are alternate, somewhat longer at the top of the stem than at the bottom, and form a basket below the flowers.

This is the most widespread Collomia and is found in all Western states. It is quite common in the mountains of the Four Corners area.

Collomia linearis

Collomia linearis (Linear-leaf Collomia)
Polemoniaceae (Phlox Family)

Foothills, montane. Woodlands, meadows, openings. Spring, summer.
Narraguinnep Natural Area, May 28, 2004; Meadows, Western San Juan National Forest, June 10, 2010; Lower Calico Trail, August 10, 2016.

Although Collomia linearis flowers are quite small, just 8-15 mm long, they occur in attractive clusters and are generally oriented vertically facing you as you come on them along the trail. They almost always occur in clusters of plants, making them even more noticeable.

The same gleaming glandularity that dots the flower head and flower tubes of Collomia grandiflora, dot Collomia linearis. The flower head is also punctuated by small, leaf-like bracts.

When flowers fade, clusters of brown-white seed capsules catch your attention. See the last photograph below for a view of hundreds of drying seed capsules.

Collomia linearis

Collomia linearis (Linear-leaf Collomia)
Polemoniaceae (Phlox Family)

Foothills, montane. Woodlands, meadows, openings. Spring, summer.
Western San Juan National Forest, May 19, 2020; Salt Creek Trail near Roaring Fork Road, August 17, 2020.

The winter of 2018-2019 saw nearly twice normal snowfall and the wildflowers of 2019 were often unusually numerous and robust. Conditions were perfect for many species and they produced an abundance of seeds. Look carefully at the above photograph and you will find over two dozen tiny annual Collomia linearis dotting a few square feet of forest floor. Nearby there were many hundreds, perhaps thousands, of one to two inch tall Collomia linearis, but because there was very little snow at mid and lower elevations in the winter of 2019-2020 and almost no spring rain, many of the tiny plants were already dying when I took the photograph and very few will survive.

At higher elevations, however, winter snow of 2019-2020 was about normal and in the summer of 2020 Collomia linearis flowered in massive numbers. Unfortunately summer rains were minimal and C. linearis life span was short; by early August if was wilted and dying, as shown in the photograph immediately above.

Species present in state and native
Species present in state and exotic
Species not present in state

County Color Key

Species present and not rare
Species present and rare
Species extirpated (historic)
Species extinct
Species noxious
Species exotic and present
Native species, but adventive in state
Eradicated
Questionable presence

Range map for Collomia grandiflora

Range map for Collomia linearis