Hackelia venusta
Encyclopedia
Hackelia venusta is a rare species of flowering plant in the borage family
Boraginaceae
Boraginaceae, the Borage or Forget-me-not family, include a variety of shrubs, trees, and herbs, totaling about 2,000 species in 146 genera found worldwide.A number of familiar plants belong to this family....

 known by the common name showy stickseed, or lesser showy stickseed. It is endemic to Washington State in the United States, where it is known from only one canyon in Chelan County. There is only one small population with a global distribution of less than one hectare
Hectare
The hectare is a metric unit of area defined as 10,000 square metres , and primarily used in the measurement of land. In 1795, when the metric system was introduced, the are was defined as being 100 square metres and the hectare was thus 100 ares or 1/100 km2...

. The plant was federally listed as an 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 in 2002.

This is a perennial herb producing several leafy stems up to 20 to 40 centimeters tall from a taproot
Taproot
A taproot is an enlarged, somewhat straight to tapering plant root that grows vertically downward. It forms a center from which other roots sprout laterally.Plants with taproots are difficult to transplant...

. The plant blooms in April and May, bearing clusters of white or blue-tinged flowers. Each flower is about 2 centimeters across with five rounded lobes and a short tubular throat. The fruit is a nutlet covered with stiff hairs that allow it to attach to the fur of animals and be dispersed
Seed dispersal
Seed dispersal is the movement or transport of seeds away from the parent plant. Plants have limited mobility and consequently rely upon a variety of dispersal vectors to transport their propagules, including both abiotic and biotic vectors. Seeds can be dispersed away from the parent plant...

 from the parent plant. The hairs are stiff enough to cling to human skin.

The plant is only found in Tumwater Canyon within the Tumwater Botanical Area in Wenatchee National Forest
Wenatchee National Forest
Wenatchee National Forest is a U.S. National Forest located in Washington. With an area of 1,735,394 acres , it extends about 137 miles along the eastern slopes of the Cascade Range of Washington, USA from Okanogan National Forest to Gifford Pinchot National Forest...

. Any other populations have been extirpated
Local extinction
Local extinction, also known as extirpation, is the condition of a species which ceases to exist in the chosen geographic area of study, though it still exists elsewhere...

 or determined to belong to other species. This plant grows in open talus
Scree
Scree, also called talus, is a term given to an accumulation of broken rock fragments at the base of crags, mountain cliffs, or valley shoulders. Landforms associated with these materials are sometimes called scree slopes or talus piles...

 and rock ledges between stands of Ponderosa pine and Douglas-fir
Douglas-fir
Douglas-fir is one of the English common names for evergreen coniferous trees of the genus Pseudotsuga in the family Pinaceae. Other common names include Douglas tree, and Oregon pine. There are five species, two in western North America, one in Mexico, and two in eastern Asia...

. The soil is sandy and rocky and low in nutrients, and few other plants grow in it. The plant does not tolerate shade. The openings are in an early stage of ecological succession
Ecological succession
Ecological succession, is the phenomenon or process by which a community progressively transforms itself until a stable community is formed. It is a fundamental concept in ecology, and refers to more or less predictable and orderly changes in the composition or structure of an ecological community...

, a stage which is maintained by wildfire
Wildfire
A wildfire is any uncontrolled fire in combustible vegetation that occurs in the countryside or a wilderness area. Other names such as brush fire, bushfire, forest fire, desert fire, grass fire, hill fire, squirrel fire, vegetation fire, veldfire, and wilkjjofire may be used to describe the same...

 that periodically clears trees and shrub
Shrub
A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...

s. As fire suppression is practiced in forests to protect property, large and woody vegetation grows up and shades out the rare plant and other shade-intolerant species. The prevention of fire also allows a layer of nutrient-rich leaf-litter and other material to build up on the forest floor, allowing many other plants to grow and compete with the stickseed. In addition, when a fire does occur after a longer period the flames burn hotter and are more destructive, killing roots that might otherwise survive a mild fire, and increasing the likelihood of landslide
Landslide
A landslide or landslip is a geological phenomenon which includes a wide range of ground movement, such as rockfalls, deep failure of slopes and shallow debris flows, which can occur in offshore, coastal and onshore environments...

s and erosion
Erosion
Erosion is when materials are removed from the surface and changed into something else. It only works by hydraulic actions and transport of solids in the natural environment, and leads to the deposition of these materials elsewhere...

.

The species is threatened by its small size, as its single population could be easily eliminated by a single large event. It is threatened by the lack of suitable habitat, which has been reduced in size by factors such as fire suppression. Introduced species
Introduced species
An introduced species — or neozoon, alien, exotic, non-indigenous, or non-native species, or simply an introduction, is a species living outside its indigenous or native distributional range, and has arrived in an ecosystem or plant community by human activity, either deliberate or accidental...

 of plants such as Dalmatian toadflax have invaded the area. Road maintenance practices, herbicide
Herbicide
Herbicides, also commonly known as weedkillers, are pesticides used to kill unwanted plants. Selective herbicides kill specific targets while leaving the desired crop relatively unharmed. Some of these act by interfering with the growth of the weed and are often synthetic "imitations" of plant...

s, and pollution
Pollution
Pollution is the introduction of contaminants into a natural environment that causes instability, disorder, harm or discomfort to the ecosystem i.e. physical systems or living organisms. Pollution can take the form of chemical substances or energy, such as noise, heat or light...

 may have contributed to the rarity of the plant. The seedling
Seedling
thumb|Monocot and dicot seedlingsA seedling is a young plant sporophyte developing out of a plant embryo from a seed. Seedling development starts with germination of the seed. A typical young seedling consists of three main parts: the radicle , the hypocotyl , and the cotyledons...

s of the species have a low rate of survivorship, with few growing to mature size. The small size of the population suggests there is a small gene pool
Gene pool
In population genetics, a gene pool is the complete set of unique alleles in a species or population.- Description :A large gene pool indicates extensive genetic diversity, which is associated with robust populations that can survive bouts of intense selection...

.

In 2010 the total population of this species was estimated to be no more than 772 individuals. Research suggests that to be viable it would need to exceed 1000.

External links

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