''Juncus digitatus'' is a rare species of

rush Rush(es) may refer to: Places United States * Rush, Colorado * Rush, Kentucky * Rush, New York * Rush City, Minnesota * Rush Creek (Kishwaukee River tributary), Illinois * Rush Creek (Marin County, California), a stream * Rush Creek (Mono Cou ...

known by the common name finger rush. It is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

Shasta County, California Shasta County (), officially the County of Shasta, is a County (United States), county in the Northern California, northern portion of the U.S. state of California. Its population is 182,155 as of the 2020 census, up from 177,223 from the 2010 c ...

, where it is known from only two occurrences near Shingletown.California Native Plant Society Rare Plant Profile
/ref> It occurs in spring-moist habitat such as

vernal pool Vernal pools, also called vernal ponds or ephemeral pools, are seasonal pools of water that provide habitat for distinctive plants and animals. They are considered to be a distinctive type of wetland usually devoid of fish, and thus allow the safe ...

s in sunny locations in the foothills of the southernmost

Cascade Range The Cascade Range or Cascades is a major mountain range of western North America, extending from southern British Columbia through Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as the North Cascades, ...

.Witham, C. W. and P. F. Zika. (2008)
''Juncus digitatus'' (Juncaceae), a new annual rush from Shasta County, California, USA.
''J Bot Res Inst Texas'' 2:2 775-81. The plant was first collected in 1991 and described to science as a new species in 2008.

Description

''Juncus digitatus'' is an annual herb forming small, dense clumps of thin, almost hairlike stems which are red in color much of the time and measure up to 10 centimeters tall. The leaves have blades no more than about 2 centimeters long and are mostly limited to the base of the plant. The

inflorescence An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...

is a single flower or a cluster of up to 8 flowers at the tips of the stems. Each flower has six lance-shaped

tepal A tepal is one of the outer parts of a flower (collectively the perianth). The term is used when these parts cannot easily be classified as either sepals or petals. This may be because the parts of the perianth are undifferentiated (i.e. of very ...

s a few millimeters in length which are reddish to greenish darkening to purplish near the tips. The fruit is a red or brownish, fingerlike capsule 1 to 2 centimeters long. ;Conservation ''Juncus digitatus'' is most closely related to '' Juncus triformis'', which grows alongside it in one of the populations but not the other. Both populations of the plant are threatened.The Nature Conservancy
/ref> Suitable habitat has been reduced by the conversion of the land to

agriculture Agriculture or farming is the practice of cultivating plants and livestock. Agriculture was the key development in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that enabled people to ...

. The spring water that feeds its natural habitat has been diverted by pipeline from one population, and the other may be impacted by ornamental rock mining.

References

External links

Jepson Manual Treatment — ''Juncus digitatus''''Juncus digitatus'' Photo gallery
digitatus Endemic flora of California Natural history of Shasta County, California Plants described in 2008 Critically endangered flora of California {{Poales-stub