December 2012 Number 1 - Utah Native Plant Society

Calochortiana December 2012 Number 1
individuals would dip as low as previously recorded
estimates seems doubtful.
Tecopa Bird’s-Beak (Cordylanthus tecopensis):
Tecopa bird’s-beak is a hemiparasitic summer annual
plant that is a Nevada Sensitive Species. It is known
from approximately ten extant occurrences across a narrow
range in California (Death Valley) and Nevada
(AMNWR) (Morefield 2001). Its habitat includes Mohave
Desert scrub and alkali flats and meadows below
2,700 feet. It always grows with Distichlis spicata,
which may be its principal host. Tecopa bird’s-beak is
also a known associate of the spring-loving centaury
and often occurs within the same habitat types (Otis Bay
and Stevens Ecological Consulting 2006). Population
estimates provided by the NNHP document >4,379 total
individuals.
Because of their similar habitat requirements, populations
of Tecopa bird’s-beak were mapped and surveyed
in conjunction with spring-loving centaury in
2008. New occurrences were discovered along the
shores of lower Crystal Marsh as well as on the west
side of the marsh within old agricultural fields. The agricultural
field population extended intermittently to the
western Refuge boundary. In addition, a significant
population was found associated with a new springloving
centaury population in a narrow band of velvet
ash located northwest and southeast of Collins Ranch.
This area appears to be an important site for multiple
rare and endemic species at the Refuge. The total population
of Tecopa bird’s beak documented in the 2008
field season is approximately 829,918 individuals.
Ash Meadows Sunray (Enceliopsis nudicaulis var.
corrugata): Ash Meadows sunray is an endemic variety
of a widely distributed species that has been listed as
threatened by the USFWS. The variety is almost strictly
endemic to Ash Meadows with a few individuals reported
from outside the Refuge in eastern California. It
is largely restricted to strongly alkaline, poorly drained,
saline soils associated with springs and dry washes but
with the water table some distance below the surface.
Lower elevation alkali clay soils in Ash Meadows have
a shallow underlying water table that makes the habitat
unsuitable. This species is associated with Ash Meadows
milkvetch, shadscale saltbush, matchbrush, alkali
goldenbush, basin yellow cryptantha (Cryptantha confertifolia)
and white bearpoppy at elevations from 2,100
to 2600 feet. It is generally found on dry to sometimes
moist sites that are on open, hard, white clay hills with
calcareous hardpans. Populations on the Refuge are
found in occasionally moist alkaline soils, spring and
seepage areas, and dry desert washes. The plants can
also occasionally be found in salt desert shrubland and
desert pavement habitats (Morefield 2001; Otis Bay and
Stevens Ecological Consulting 2006). The last con-
firmed population estimates for this plant were reported
following its listing as a threatened species.
The 2008 survey was directed at locating the plants
throughout all potential habitat types occurring within
the Refuge. Cruise transects 40 meters apart were used
to survey large tracts of Ash Meadows. Of the more
than 9,000-acres of potential habitat, nearly 6,000 acres
have been surveyed to date. Ash Meadows sunray has
been found throughout the areas mapped by the Refuge
in 2006. In several cases known populations have been
extended beyond previous distribution boundaries. New
occurrences were documented west of known populations
mapped along Ash Meadows Road, as well as on
the alluvial fans east of Point of Rocks and south of
Jackrabbit Spring. A single occurrence was also documented
adjacent to Lower Crystal Marsh. The preliminary
population estimate, calculated with approximately
two-thirds of the survey complete, is 50,954 individuals.
The remaining survey area includes habitat within the
central portion of the Refuge that has long been known
to support this plant. It is likely that upon completion of
the surveys, the final population estimate will increase
by several thousand.
Ash Meadows Gumplant (Grindelia fraxinopratensis):
Ash Meadows gumplant was listed as threatened
by the USFWS in 1985. The plant is considered an
endemic species primarily occurring within AMNWR
with a limited distribution in neighboring Inyo County,
California. NNHP documented 16 occurrences across
the known range for the species and estimated a population
of more than 13,000 individuals in 1986 (Morefield
2001). The USFWS estimated the Refuge’s population
at approximately 81,000 individuals following a 1998
survey (USFWS 2007a).
Distribution data provided by the USFWS in 2000
and Refuge staff in 2006 indicate that populations of G.
fraxinopratensis occur in spring drainages and marsh
habitats throughout the Refuge. Notably, both data sets
show a significant presence of this species along the
Fairbanks and Rogers Spring drainages. However, BIO-
WEST botanists involved with the 2007 reconnaissance
and the 2008 surveys indicate that plants found at these
locations are actually not members of this species. At
this time BIO-WEST has been unable to confirm occurrences
north or west of the Warm Springs complex.
The Alkali Meadows south of Crystal Reservoir contain
very large populations of Ash Meadows gumplant.
Known populations were also documented in the Alkali
Meadows of the Big Spring/Jackrabbit Spring drainage
complex both east and west of South Spring Meadows
Road. Another known population was inventoried south
of Ash Meadows Road as it intersects South Spring
Meadows Road. New populations were surveyed between
the Warm Springs Complex and West Spring
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