By Mark Gutglueck
The desert spring parsley, which is known as both the desert cymopterus, desert spring parsley and by its Latin name, Cymopterus deserticola, is an endangered four to six inch purple plant of the Apiaceae family that is endemic to the Mojave Desert.
It is included in inventory of rare and endangered plants. At present, fewer than 7,000 of the plants are known to exist. It is threatened by sheep grazing, urbanization and vehicles.
It was once relatively common in the area around Apple Valley but by 1988 it had disappeared from there, lost due to urban development and off-highway vehicle use. It also appears to have disappeared from Fort Irwin.
The entire known range of desert cymopterus occurs in the western Mojave Desert within the Western Mojave Planning Area.
It grows in creosote bush scrub and Joshua tree woodland of the Mojave Desert, from east of Victorville to Kramer Junction and the Cuddeback Lake basin, and across the San Bernardino County/Los Angeles County and Kern County borders in the area on and around Edwards Air Force Base, particularly in the Rogers and Buckhorn Dry Lake basins.
The desert cymopterus has no stem, instead sending its erect petioles holding the leaves and erect peduncles bearing the flowers straight out of the sand. Each leaf upon the petiole is a dull green and thick and fleshy, divided into several rubbery-looking leaflets which are again divided into triangular pointed lobes. The inflorescence is a spherical umbel of tiny purplish corollas surrounded by large green bracts.
Cymopterus deserticola was originally described by Townshend Stith Brandegee in 1915.
This species occurs at elevations from 2,000 to 3,000 feet, and possibly up to 5,000 feet, in loose, sandy soils. The sandy soils required by this species occur on alluvial fans and basins, stabilized sand fields, and occasionally sandy slopes of desert dry lake basins. As a taprooted perennial, desert cymopterus does not appear to reproduce vegetatively, but rather reproduces via seeds. Seedling establishment has not been reported for this species.
Part of the challenge to the plant’s survival is that the plant needs sufficient water to produce seeds and in dry years, the establishment of new individuals are infrequent. Many reported desert cymopterus populations are highly dispersed and of low density. Their thinning further in dry years and lack of dispersing has resulted in a declining population.
Depending on the year, desert cymopterus flowers between early March and mid-May, and may not flower at all in unfavorable years. Poor seed production or seed survival are factors in infrequent establishment observed in field studies. At a number of sites in several different years little or no seed production has been observed.
A study conducted in 1988 at five sites found that the inflorescences dried up and aborted before setting fruit at each site. In a 1992 study at three sites on Edwards Air Force Base, it was reported that only a small portion of the plants flowered and that even fewer successfully produced seed. On the other hand, in 1995, a wet El Niño year, ninety-five percent of the plants produced inflorescences at the same three sites, and fifty-one percent of the plants had set fruit near the end of the growing season. However, this still indicates a lot of inflorescences aborted before setting fruit.
Fruits of the desert cymopterus are fairly large and do not seem well adapted for dispersal over long distances. Fruits generally seem to fall relatively close to the parent plant. However, the fruits have a marginal wing that may facilitate dispersal by wind. In addition, the fruits mature late in the season, typically after the end of the rainy season, so they remain dry and light. Therefore, given that wind is relatively common in the open sandy habitats where this species is found, it could easily push the fruits along the soil surface, although the fruits probably do not go airborne
As a result of annual variability in rainfall, the underground parts of
herbaceous desert perennials, including desert cymopterus, must be able to maintain the populations over time with frequent years of reproductive failure; in addition, they must be able to survive prolonged periods of low soil moisture and entire years without aboveground photosynthetic activity.
In dry years, desert cymopterus may not produce flowers or fruit and
may even remain dormant underground during the usual growing
season. In very wet years, however, they may produce flowers and fruits abundantly. Observations of abundant desert cymopterus in 1995
on Edwards Air Force Base demonstrated the species’ ability to survive the 1988–1994 drought in large numbers and with great vigor.
In 1995, the largest and most robust populations of desert cymopterus occurred on Edwards Air Force Base. Seventeen population surveys were performed that year, and population sizes at each location ranged from 1 to 1,929 individuals. In total, 14,093 individuals were counted over an area of 1,465 acres. The plant’s numbers have significantly declined in the twenty years since, however.
Desert cymopterus is potentially threatened by habitat alteration and destruction resulting from military activities on Edwards Air Force
Base, the expansion of Fort Irwin, oil and gas development, utility construction, renewable energy development, off-road vehicle use, sheep grazing, land tenure adjustment, urban development grazing by native and non-native herbivores—presumably including mammals, insects, and reptiles. The desert tortoise (Gopherus agassizii), itself a protected species, is also a threat to the desert cymopterus.
Populations of desert cymopterus are most likely sustained through
periodic recruitment only after years of exceptionally favorable conditions for seed production.
Population sizes appear to vary greatly from year to year, evidently in response to the amount and timing of winter and spring rainfall, making it difficult to determine population trends. The long-term viability of populations may hinge on the protection of habitat corridors between the existing populations and preventing any disturbance where the plants are now known to flourish.
By Mark Gutglueck