Nature Notes From Crater Lake
Volume 30, 1999
The Rare Treasure of Mount Mazama
Collomia
By Casey Baldwin
Mount Mazama Collomia (Collomia
mazama) is a beautiful and rare member of the phlox family endemic
to Crater Lake National Park and adjacent lands on the Rogue River and
Winema national forests. It is a perennial species primarily restricted
to the open woods and meadows of the lodgepole pine and true fir forest
communities of southern Oregon's Cascade Range. This species was
discovered by the noted botanist F.V. Coville along Dutton Creek, just
two air miles from Crater Lake, in 1896. Modern day explorers can still
observe a healthy population of these plants at this site (called a type
locality), though the species is considered threatened throughout its
range. There are only 55 known populations, of which 12 (or 22 percent)
occur within Crater Lake National Park.

A Mount Mazama collomia in bloom. Photo by
Casey Baldwin. |
C. mazama is one of eleven
species in the genus Collomia
found in western North America. It is herbaceous and perennial, ranging
from 15 to 30 cm tall, with broadly lanceolate leaves having distinctive
irregular teeth towards the apex. Flowers are borne in terminal,
head-like cymes, and possess funnelform shaped corollas up to 1.5 cm
broad; coloration is lilac, bright purple, deep blue, or violet. Adding
to its beautiful appearance are the exerted stamens with powder blue
anthers. The inflorescence is covered with glandular hairs that exude a
slight skunky odor. Three small, black seeds are produced per capsule
and are explosively dehiscent -- where seeds have been observed to
disperse up to half a meter. Flowering occurs from June through
September.
Two other perennial, blue-flowered
Collomia species occur at high elevations in Oregon. These are C.
debilis var. debilis and
C. larsenii. C. debilis can be distinguished from C. mazama
by its larger flowers (1.5 to 3.5 cm) and sprawling habit. It is only
found in central and northeastern Oregon. C. larsenii is also
distinguished by its sprawling habit, and pinnately- or palmately-lobed
leaves, as compared to the erect habit and toothed leaves of C.
mazama. Collomia larsenii occurs in the Olympic Mountains and
Cascade Range.
Collomia mazama predominately
inhabits places at high elevation (4800 to 6300 feet), where it
associates with mountain hemlock, red/noble fir, and lodgepole pine.
Minor habitats include the mixed conifer forest, the interface of
meadows with incense-cedar, and riparian areas. The largest C. mazama
population found within Crater Lake National Park is located on the
middle fork of Copeland Creek, near the Pacific Crest Trail. White fir
(Abies concolor),
Red noble fir (A. magnifica-procera), lodgepole pine (Pinus
contorta), incense-cedar (Calocedrus decurrens), and mountain
hemlock (Tsuga mertensiana) are present in the overstory, with
thinleaf huckleberry (Vaccinium membranaceum), Crater Lake
currant (Ribes erythrocarpum), and baldhip rose (Rosa
gymnocarpa) in the understory. Other large populations of Mount
Mazama collomia occur along lower Bybee Creek and southwest of Sphagnum
Bog along Crater Creek, whereas smaller populations occur along the
north and south forks of Copeland Creek, Sphagnum Bog, and upper Bybee
Creek. The Dutton Creek population, along with those between Sphagnum
Bog and the Pacific Crest Trail, occur where lodgepole pine, scattered
red/noble fir, and mountain hemlock dominate the forest canopy. In these
places grouse huckleberry (V. scoparium), two-colored lupine (Lupinus
bicolor), meadow penstamon (Penstamon rydbergii), and long-stolon
sedge (Carex pensylvanica) largely comprise the understory. The
population at Thousand Springs is the smallest (less than 35
individuals) but the most unique in the park, occurring in the drier
portion of a riparian zone with associated huckleberry and a sparse
overstory of lodgepole pine and red/noble fir.

Mount Mazama Collomia. Drawing by Charles F.
Yocum, ca. 1951. |
Concern over the long-term viability of
Mount Mazama collomia, as well as the lack of basic biological
information, prompted a cooperative research effort. Personnel from the
National Park Service, U.S. Forest Service, and the University of Idaho
worked together in developing a comprehensive conservation strategy. At
the same time, grants from Canon USA, Stillinger Botanical, and the
Mazamas assisted me with gathering data on the plant's genetic
structure, reproductive biology, demography, and ecology. The most
relevant findings are summarized in the following paragraphs.
A genetic analysis of 20 populations
from Crater Lake National Park and surrounding national forest lands was
conducted using starch gel electrophoresis. The overall genetic
diversity turned out to be low, with only 2 of 22 loci exhibiting more
than one allele. Most of the genetic variation is contained between
populations (particularly the northern versus southern, with Red Blanket
Creek being a rough dividing line). In all likelihood, the distinction
is due to random genetic drift. This is probably due to small population
sizes sometime in the past, a characteristic common to many species of
rare plants. Populations within and immediately adjacent to Crater Lake
National Park contain the highest levels of genetic diversity within the
species and thus represent a valuable genetic resource.
Another study tracked demographics
(birth, growth, death, and reproductive success) of eight C. mazama
populations that occupy the range of habitats in which this species is
typically found. Over 4,000 individuals were located, marked, and
measured over a four year period. Research results indicate that a large
number of seeds may be produced during a given year (up to 750 seeds per
square meter) but the rates of germination and survival are extremely
low. No more than ten percent of seeds will germinate the following
year, with a mortality rate of 50 percent in each of the successive
growing seasons. Seedling growth averages one centimeter per year, with
flower and seed production beginning at a height of 5-10 cm, or at an
estimated age of 7-12 years. Up to 50 percent of the plants flowering in
a given season will not flower the following year, and approximately 10
percent of the population will be dormant for a full growing season.
Additionally, predation by deer appears to play a significant role in
the population dynamics of this species, with up to 45 percent of a
population being eaten before setting seed. Taken together, these
factors indicate that the rarity of this plant may be due to the
combination of low survivorship, slow growth rates, and predation.
Restoration efforts
According to one survey, several C.
mazama populations have been impacted by activities associated with
the trail system in Crater Lake National Park. Both seedlings and
vegetatively propagated clones are being evaluated so as to find the
best way to restore these populations. Due to the relatively slow growth
rate of seedlings, it was thought that the use of material propagated
from mature plants would result in better reestablishment. Results from
the propagation of seedlings and vegetative clones in a greenhouse
environment showed that both grow at the same rate, flowering after
reaching a height of 7 cm. Flowering is a function of plant height,
whereas the growth rate seen in seedlings is the result of environmental
conditions. Field trials were initiated in the latter part of 1997 to
evaluate the establishment of seedlings and vegetative clones on
compacted and non-compacted sites in both spring and fall plantings. The
only observed difference so far is that spring plantings have a higher
mortality rate due to predation by deer.
Efforts to restore Mount Mazama
collomia within Crater Lake National Park are promising, yet this rare
plant continues to face a variety of threats throughout its limited
range. We can hope, however, that the research and conservation efforts
made by scientists, land managers, and volunteers so far will continue
making headway. Collomia mazama
is a botanical treasure, one to be enjoyed now and by future
generations.
Casey Baldwin is a doctoral
candidate at the University of Idaho and the principal author of a
conservation strategy for Mount Mazama collomia.

Drawing appeared in "The Community House," Nature
Notes from Crater Lake, 5:3 September 1932.