Penstemon haydenii

Penstemon haydenii[1]
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Asterids
Order: Lamiales
Family: Scrophulariaceae
Genus: Penstemon
Species: P. haydenii
Binomial name
Penstemon haydenii
S. Watson

Penstemon haydenii, the blowout beardtongue[3] or blowout penstemon, is a species of beardtongue in the Plantaginaceae family. The warm-season perennial plant is native to nine counties in the Nebraska Sand Hills and a single location in Carbon County, Wyoming.[2][4] The plant has a milky-blue color with a waxy cuticle, pale purple leaves, and alternating leaf pattern with one central stock. The flowers, while in the inflorescence stage, originate from the bases of the leaves of the plant. Blowout penstemon flowers from May until early June and drops the seeds late August into September.

Blowout penstemon grows on bare sand dunes. It is resistant to the abrasive forces of the blowing sands with its incorporation of a protective thick waxy cuticle. Other plants are often cut off by the scouring sands as they sprout.

Another adaptive feature for the blowout penstemon plant is the lifespan of the seeds. The seeds dropped in late August into September can remain buried dormant in the sandy soils for decades and still remain viable. Prolonged wet conditions and abrasion are required for breaking dormancy and seed germination. The plant is primarily an out-crosser (transfers genes from one plant of the same species to another plant of the same or closely related species); although studies show that it is potentially self-fertile.[5]

Habitat

Blowout penstemon was only known from the Sandhills of Nebraska until the recent discovery of limited populations in Wyoming. Blowout penstemon is only found in sandy locations with little to no vegetation present. Due to the uncompetitive nature of the plant it is easily outcompeted by other plants in the succession scheme. The ever-shifting sandy soils of the Sandhills provide blowout penstemon with an ideal environment with little to no competition for water, nutrients, and sunlight. The nature of the plant is to develop these blowout conditions and promote succession.

Blowouts are the only habitat to which the plant grows, hence the name. The Sandhills of western Nebraska provide just this habitat needed for the blowout penstemon to grow and survive.

Endangered When & Why

Blowout penstemon was declared an endangered species on September 1, 1987, due to its small numbers and habitat limitations. The direct cause of the reduced habitat is partly due to improvement of land management practices and control of fire in the Sandhills. Prior to the changes in management practices, land owners often created the blowout conditions with the incorrect implementation of stocking densities, by essentially overstocking. In addition, there was no consistent method for blowout control protocol. The more current management practices often follow a more concise grazing scheme that promotes the improvement of range conditions and indirect reduction of habitat reduction for blowout penstemon.

Reduction of fire in the Sandhills has also had a very detrimental effect on the habitat for blowout penstemon as well. Fire acted as a means for removing debris and litter from the soil surface opening up the bare soil to be more vulnerable to wind erosion. This increase in wind erosion causes the growing conditions for other plants to be more unfavorable reducing competition from other species on blowout penstemon.

As the control of wild fires becomes more widespread, it promotes the development of the dunes to rangeland and the elimination of blowout sites. Fire in the Sandhills has been more extensively controlled because of their detrimental effects. With the technology and resources available it is also easier to control and contain wildfires that may naturally occur.

Major Threats

Blowout penstemon has four known threats that suppress numbers and available habitat. One of the first being human intervention, as is the major cause of many species to become endangered and extinct. Another is caused by the climatic conditions, unfavorable growing conditions. Plant competition and insect damage are also contributing factors in the endangerment of the blowout penstemon.

The improvement of land management practices and control of fire is a direct human influence on the habitat conditions needed for the growth and development of blowout penstemon populations. In addition to these management plans, land managers may also reshape the blowouts with machinery to reduce the swirling action of winds. There are several common ways of leveling off the sharp edges of the blowouts. Mechanical means are often used to reshape the blowouts. Cattle are used to reshape the land and provide a layer of litter and debris.

Climatic conditions have been thought to be a factor in the reduced numbers as well. Because the seeds require wet conditions to break dormancy, drought can be a factor. The lack of moisture discourages the development of the seeds and promotes prolonged dormant stage.

Plant competition is another large contribution to the reduction in numbers of the blowout penstemon plants. The penstemon provides shelter for other plants, increasing plant growth and decreasing the amount of windblown sand. The new plants then compete with the penstemon. Blowout penstemon in a blowout is one of the first signs of blowout recovery; to a land manager this is a positive sign for increased range condition and increased productivity.

Insect damage also accounts for a considerable negative influence on the plants survival ability. "The most serious insect problem is probably the larvae of the pyralid moth, which bores into the stem and root crowns of the blowout penstemon plant to pupate. This can cause a 75% mortality rate of the affected plants"[6]

Recovery Plans

Conservation activities include a form of regular surface disturbance that promotes the blowout environment and reduction of plant development. Oil and gas companies have been opened up into habitat known for blowout penstemon with strict regulations concerning surface disturbances. This intensive management is yet once again not a blanket policy; rather it is dealt with on a case by case level, depending on the year, climatic conditions, seasonal timing, and rehabilitation state of the stand.

As a type of insurance for the existence of the blowout penstemon plant, seeds have been and are currently being collected and stored in seed banks to ensure the continuation of this species and to prevent extinction from occurring. These seeds may even be used at a later date to introduce them into a new environment. Other management practices include elimination of all-terrain vehicles.

Notes

  1. ↑ Germplasm Resources Information Network. "Penstemon haydenii information from NPGS/GRIN". Retrieved 2008-07-25.
  2. 1 2 United States Fish and Wildlife Service. "Species Profile for Blowout penstemon (Penstemon haydenii)". Retrieved 2011-02-26.
  3. ↑ "Penstemon haydenii". Natural Resources Conservation Service PLANTS Database. USDA. Retrieved 22 September 2015.
  4. ↑ United States Fish and Wildlife Service (1999-11-01). "U.S. Fish and Wildlife Service Announces Discovery of Endangered Plant, Blowout Penstemon, in Wyoming". Retrieved 2011-02-26.
  5. ↑ Fertig, Walter. 2000. Status of Blowout Penstemon (Penstemon haydenii) in Wyoming.” Prepared by the Wyoming Natural Diversity Database for the Wyoming Cooperative Fish and Wildlife Research Unit, U.S. Fish and Wildlife Service, and Wyoming Game and Fish Department.
  6. ↑ Stubbendieck, J., J. Lamphere, and J.B. Fitzgerald. 1997. Nebraska Threatened and Endangered Species, Blowout Penstemon. Nebraska Game and Parks Commission. Pamphlet.

References

See also

This article is issued from Wikipedia - version of the Tuesday, September 22, 2015. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.