Purple Amole

Chlorogalum purpureum var. purpureum Chlorogalum purpureum var. reductum

Description

When the purple amole was listed, the listing included two varieties, Chlorogalum purpureum var. purpureum and C. p. var. reductum. Both varieties of the purple amole have a basal rosette of linear leaves 0.1-0.2 in (2-5 mm) wide with wavy margins. Stems are widely branching and stand 10-16 in (25-40 cm) high for the C. p. var. purpureum and 4-8 in (10-20 cm) for the C. p. var. reductum. The stems support small bluish-purple flowers with six recurved petals.

This species is most likely mycorrhizal. This relationship between its roots and a fungus aids in nutrient and water uptake, altering growth and competitive interactions with other species. Reproduction is primarily by seed and pollination is accomplished by insects.

The purple amole can be distinguished from others in its genus because it is the only member of the genus with bluish-purple flowers that open during the day.

Habitat

The purple amole is typically found in grasslands, oak woodlands, and oak savannahs in the south coast range of California, in elevations between 0 and 2,050 ft (0-620 m).

In the case of the C. p. var. purpureum, the plant is known to occur on flat or gently sloping terrain with sparse numbers of herbaceous vegetation. The upper layer of soil is gravelly, covering the clay soils below.

One particular population of C. p. var. reductum is on a flat-topped ridge, or plateau, associated with a blue oak savannah. This plateau is probably the remains of an ancient elevated alluvial terrace that is eroded away by surrounding drainages, and now contains red clays with a large component of gravel and pebbles.

Distribution

Historically, the purple amole may have existed in the Jolon Valley of southern California, but most of the suitable habitat was flatlands that have since been converted to cropland, pasture, or vineyards.

Both varieties of the purple amole now occur in the southern coast ranges. C. p. var. purpureum can be found in three locations in Monterey County near Jolon. In all cases, the lands are managed by Fort Hunter Liggett of the Department of the Army. One population of several thousand plants is discontinuous and scattered over an area 4-6 mi (7-9 km) long and 3 mi (5 km) wide near housing and administration on the base. The second population contains around 400-500 plants and the third population supports up to 10,000 plants.

The C. p. var. reductum occurs in the La Panza Range of San Luis Obispo County in two sites. The larger population ranges from 1,000 to several hundred thousand individuals in patches on a plateau bisected by a State highway. South of the highway it is on the Los Padres National Forest (LPNF) and north of the highway it is on private lands. The second population is in two or more patches on private land south of the LPNF. The population consists of several hundred plants on less than 0.25 acres (0.1 hectare).

Threats

Both varieties are affected by loss, fragmentation, and alteration of habitat.

C. p. var. purpureum is subject to projects proposed by the military. Road building and development have been known to isolate populations and degrade remaining habitat near and army facilities. The other populations are on training facilities and a subject to trampling, compaction of soil, removal, and competition with non-native species due to activities.

Also contributing to the stress of the C. p. var. purpureum are the alteration of fire cycles, livestock grazing, and increased numbers of non-native species invading habitat due to disturbance.

A major threat to the C. p. var. reductum is off-highway vehicles (OHVs). Most of the population on public lands is in a place that was once a staging area for OHV enthusiasts. Fence was installed and pipe barriers were placed to protect the population from trampling by OHVs. Vehicles continue to trespass through broken fences and tracks have been found in the population.

Other threats include grazing and livestock use, expanded grading along the highway, dust from the road, and invasion by non-native species.

Conservation and Recovery

Each variety of Chlorogalum purpureum will have separate recovery units designated. The need for critical habitat designation has been deemed prudent, and will be discussed depending on the magnitude and immediacy of the threats.

The army has stated that they are willing to enter an agreement which will protect the C. p. var. purpureum from future development.

Steps have been taken to protect the C. p. var. reductum. Where it exists on public land, the California Native Plant Society in conjunction with the LPNF have installed fences to protect the population. Biologists have attempted to establish seedlings in OHV tracks. The landowner who owns the property where the smaller population occurs has stated interest in the plant and its protection.

Contacts

U. S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
Eastside Federal Complex
911 N. E. 11th Ave.
Portland, Oregon 97232-4181
(503) 231-6121
http://pacific.fws.gov/

Ventura Fish and Wildlife Office
U. S. Fish and Wildlife Service
2493 Portola Road, Suite B
Ventura, California 93003-7726
Telephone: (805) 644-1766

References

United States Department of the Interior. 20 March 2000. "Endangered and Threatened Wildlife and Plants: Determination of Threatened Status forChlorogalum pupureum (Purple Amole), a Plant From the South Coast Ranges of California." Federal Register 65 (54): 14878-14888.

University of California, Berkeley. "Chlorogalum purpureum." CalFlora Database Project: a botanical resource for California on the internet. (http://dlp.cs.berkeley.edu/calflora.) Date Accessed: July 6, 2000.