Penstemon penlandii
Encyclopedia
Penstemon penlandii is a rare species of flowering plant in the plantain family
known by the common names Penland penstemon and Penland's beardtongue. It is endemic to Colorado
in the United States, where it is known only from a strip of land about five miles long in central Grand County
. There are two occurrences totalling about 8600 individuals. This is a federally listed endangered species
of the United States.
This plant was discovered in the 1980s during surveys for Osterhout's milkvetch
(Astragalus osterhoutii), another rare local endemic. The two plants are found only in Middle Park
, a valley with seleniferous
badlands
that host a unique flora. The penstemon grows in clay
that is rich in selenium, an element toxic to most other plants in high concentrations. In adjacent stretches of land that have a lower selenium content the penstemon population becomes thinner and it is replaced by sagebrush
. The penstemon grows in the shade of the banks of runoff channels that are periodically flooded; the plant's deep, ropelike roots and rhizome
anchor it to underground shale
deposits to prevent it from being torn away during flood
s.
This perennial herb arises from a woody caudex attached to the thick root system. The flowering stems are up to 25 centimeters tall with small, linear leaves. The inflorescence
contains up to 15 purple-blue flowers each measuring roughly 1.5 centimeters long. They are tubular opening into wide mouths containing staminode
s tipped with orange hairs. The plants are partly self-compatible
, but for more efficient fruit production the flowers must be visited by pollinator
s. Many species of bees, especially of genus Osmia, pollinate the flowers, as does the beardtongue-specialist pollen wasp Pseudomasaris vespoides. Blooming occurs in June and July.
The plant occurs in a section of land in northern Middle Park measuring about 5 miles or 2.4 kilometers long and under a kilometer wide. It was added to the US Endangered Species List the same day as its fellow local endemic Osterhout's milkvetch. They are both naturally rare and are threatened by off-road vehicle
use in their barren, dry habitat. The penstemon is threatened by the maintenance of a nearby road. Mineral exploration may also be a threat in the area.
Plantaginaceae
Plantaginaceae Juss. or plantain family, are a family of flowering plants in the order Lamiales. The type genus is Plantago L..In older classifications it used to be the only family of the order Plantaginales, but numerous phylogenetic studies, summarized by the Angiosperm Phylogeny Group, have...
known by the common names Penland penstemon and Penland's beardtongue. It is endemic to Colorado
Colorado
Colorado is a U.S. state that encompasses much of the Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains...
in the United States, where it is known only from a strip of land about five miles long in central Grand County
Grand County, Colorado
Grand County is the 21st largest of the 64 counties of the State of Colorado of the United States. The county population was 12,442 at U.S. Census 2000...
. There are two occurrences totalling about 8600 individuals. This is a federally listed endangered species
Endangered species
An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...
of the United States.
This plant was discovered in the 1980s during surveys for Osterhout's milkvetch
Astragalus osterhoutii
Astragalus osterhoutii is a rare species of milkvetch known by the common name Osterhout milkvetch. It is endemic to Grand County, Colorado, where it is known from a few populations in Middle Park, a mountain basin. There are five or six occurrences...
(Astragalus osterhoutii), another rare local endemic. The two plants are found only in Middle Park
Middle Park (Colorado basin)
Middle Park is a high basin in the Rocky Mountains of north-central Colorado in the United States. It is located in Grand County, on the southwest slope of Rocky Mountain National Park, approximately 50 miles west of Boulder.-Description:The basin surrounds the headwaters of the Colorado River...
, a valley with seleniferous
Selenium
Selenium is a chemical element with atomic number 34, chemical symbol Se, and an atomic mass of 78.96. It is a nonmetal, whose properties are intermediate between those of adjacent chalcogen elements sulfur and tellurium...
badlands
Badlands
A badlands is a type of dry terrain where softer sedimentary rocks and clay-rich soils have been extensively eroded by wind and water. It can resemble malpaís, a terrain of volcanic rock. Canyons, ravines, gullies, hoodoos and other such geological forms are common in badlands. They are often...
that host a unique flora. The penstemon grows in clay
Clay
Clay is a general term including many combinations of one or more clay minerals with traces of metal oxides and organic matter. Geologic clay deposits are mostly composed of phyllosilicate minerals containing variable amounts of water trapped in the mineral structure.- Formation :Clay minerals...
that is rich in selenium, an element toxic to most other plants in high concentrations. In adjacent stretches of land that have a lower selenium content the penstemon population becomes thinner and it is replaced by sagebrush
Sagebrush
Sagebrush is a common name of a number of shrubby plant species in the genus Artemisia native to western North America;Or, the sagebrush steppe ecoregion, having one or more kinds of sagebrush, bunchgrasses and others;...
. The penstemon grows in the shade of the banks of runoff channels that are periodically flooded; the plant's deep, ropelike roots and rhizome
Rhizome
In botany and dendrology, a rhizome is a characteristically horizontal stem of a plant that is usually found underground, often sending out roots and shoots from its nodes...
anchor it to underground shale
Shale
Shale is a fine-grained, clastic sedimentary rock composed of mud that is a mix of flakes of clay minerals and tiny fragments of other minerals, especially quartz and calcite. The ratio of clay to other minerals is variable. Shale is characterized by breaks along thin laminae or parallel layering...
deposits to prevent it from being torn away during flood
Flood
A flood is an overflow of an expanse of water that submerges land. The EU Floods directive defines a flood as a temporary covering by water of land not normally covered by water...
s.
This perennial herb arises from a woody caudex attached to the thick root system. The flowering stems are up to 25 centimeters tall with small, linear leaves. The inflorescence
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. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
contains up to 15 purple-blue flowers each measuring roughly 1.5 centimeters long. They are tubular opening into wide mouths containing staminode
Staminode
In botany, a staminode is an often rudimentary, sterile or abortive stamen. This means that it does not produce pollen. Staminodes are frequently inconspicuous and stamen-like, usually occurring at the inner whorl of the flower, but are also sometimes long enough to protrude from the...
s tipped with orange hairs. The plants are partly self-compatible
Self-incompatibility in plants
Self-incompatibility is a general name for several genetic mechanisms in angiosperms, which prevent self-fertilization and thus encourage outcrossing...
, but for more efficient fruit production the flowers must be visited by pollinator
Pollinator
A pollinator is the biotic agent that moves pollen from the male anthers of a flower to the female stigma of a flower to accomplish fertilization or syngamy of the female gamete in the ovule of the flower by the male gamete from the pollen grain...
s. Many species of bees, especially of genus Osmia, pollinate the flowers, as does the beardtongue-specialist pollen wasp Pseudomasaris vespoides. Blooming occurs in June and July.
The plant occurs in a section of land in northern Middle Park measuring about 5 miles or 2.4 kilometers long and under a kilometer wide. It was added to the US Endangered Species List the same day as its fellow local endemic Osterhout's milkvetch. They are both naturally rare and are threatened by off-road vehicle
Off-road vehicle
An off-road vehicle is considered to be any type of vehicle which is capable of driving on and off paved or gravel surface. It is generally characterized by having large tires with deep, open treads, a flexible suspension, or even caterpillar tracks...
use in their barren, dry habitat. The penstemon is threatened by the maintenance of a nearby road. Mineral exploration may also be a threat in the area.