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Penstemon eatonii

Penstemon eatonii is a biology topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Penstemon eatonii rather than just read about it. In short: Penstemon eatonii is a species of flowering plant in the genus Penstemon, known by the common name firecracker penstemon. It is native to the Western United States from Southern California to the Rocky Mountains.

Penstemon eatonii — main illustration
Penstemon eatonii — illustration

Key takeaways

  • Penstemon eatonii belongs to biology; place it in that map before memorising details.
  • Learn the definition first, then one example that makes the definition concrete.
  • Connect Penstemon eatonii to a quantity you can measure, compute or draw — that is where exam questions come from.
  • Reproduce the core statement of Penstemon eatonii from memory before moving on to harder problems.

Reference excerpt

Penstemon eatonii is a species of flowering plant in the genus Penstemon, known by the common name firecracker penstemon. It is native to the Western United States from Southern California to the Rocky Mountains. It grows in many types of desert, woodland, forest, and open plateau habitat.

Description Penstemon eatonii is a herbaceous plant with a few to several medium height stems that are between 30 and 100 centimeters (1.0 and 3.3 ft) when full grown. The stems can grow straight upright or might grow out and then curve to growing upwards. Their texture might be hairless or covered in backwards facing stiff hairs, but is never waxy or glaucous. It is relatively short lived perennial. Firecracker penstemon has both cauline and basal leaves, those that are attached to the stems and ones that grow directly from the base of the plant, which are very deep green and glossy. The basal leaves and lowest ones on the stems are normally 5 to 10 centimeters (2 to 4 in) in length, but on occasion may be as long as 20 cm (8 in). Their width ranges from 1.5 to 5 cm (0.6 to 2.0 in), but usually do not exceed 2.8 cm (1.1 in). The lower leaves are wider than ones further up the plant and are attached by petioles. On the stems there are three to five pairs of leaves attached on opposite sides. The lower leaves are obovate to elliptic, teardrop shaped to having ellipse shaped sides with smooth edges. Upper leaves are ovate or lanceolate, egg shaped to spear head shaped, and attach directly to the stem, sometimes with the base clasping and the shoulders of the leaf extended to be heart shaped. The inflorescence is the upper 9 to 45 cm (3.5 to 17.5 in) of the stem. Each inflorescence has four to twelve groups of flowers with a pair of opposite bracts underneath where they attach. Each group has two cymes, branched parts of the inflorescence usually with one or two flowers, but occasionally as many as four. The bright color of the flowers contrasts strikingly with the darker color of the foliage making this a very striking wildflower. The brilliant color of the bloom is variously described as cardinal red, scarlet, or orange-red. The length of the fused petals ranges from 24 to 33 millimeters (0.9 to 1.3 in). They are nearly radially symmetrical, only weakly divided into two lips, with the lobes not spreading very much.

Taxonomy In 1871 Sereno Watson described a species that he named Penstemon centranthifolius, however George Bentham had already used his name for another species in 1835, so this was an illegitimate name. The next year Asa Gray published his description of the species naming it Penstemon eatonii. It has three varieties:

Penstemon eatonii var. eatonii Penstemon eatonii var. exsertus (A.Nelson) C.C.Freeman Penstemon eatonii var. undosus M.E.Jones

It also has 7 synonyms of one of its three varieties.

Names The species name was selected to honor Daniel Cady Eaton, a botanist who worked at Yale University. In English it is most commonly called the firecracker penstemon. Eaton made botanical collections in Utah during the late 1800s. Related to its scientific name it is also known as Eaton's penstemon, Eaton penstemon, and Eaton's firecracker. It is occasionally called scarlet bugler, though Penstemon centranthifolius is also known by this name.

Range and habitat Penstemon eatonii is native to the southwestern United States, largely in southern Great Basin and the Colorado River Basin. At its eastern edges it grows in the most western counties of Colorado from Mesa County south to Four Corners. It is only found occasionally in the farthest northwest corner of New Mexico. In Utah it is found from the Wasatch Mountains southward. Its range extends through almost all of Arizona, but only in the southern part of Nevada with an isolated population in the north in Humboldt County. In the far west it reaches California grows in the Mojave Desert and the Sonoran Desert and reaches the San Bernardino Mountains. It also is reported in Wyoming and Idaho, but without specific locations. It grows in a wide variety of habitats including sagebrush steppes, pinyon–juniper woodlands, mountain mahogany scrublands, and Ponderosa pine forests. It does not display a strong preference for slopes compared with flat areas.

Conservation The conservation non-profit NatureServe evaluated Penstemon eatonii in 1990 and at that time rated it as secure (G5).

Ecology Unlike penstemons that are adapted to pollination by bees, the firecracker penstemon has a much longer and narrow floral tube and lacks the wide lobes at the flower's mouth for insects to use as landing platform. Instead it is visited by hummingbirds. The caterpillars of the anicia checkerspot (Euphydryas anicia morandi) feed on firecracker penstemons.

Uses A person from the Shoshone in Nevada interviewed by Beatty Train in the 1930s reported that red flowered penstemons, such as Penstemon eatoni, could be used to aid in healing burns. The whole plant would be boiled and then used as a wash to aid skin healing and reduce pain.

See also List of Penstemon species

References

External links

Jepson Manual Treatment Photo gallery

Illustrations

Penstemon eatonii illustration
Penstemon eatonii illustration

Worked examples

Example 1 — a first encounter with Penstemon eatonii

Start with the simplest possible case. Write down what Penstemon eatonii claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In biology, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Penstemon eatonii before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Penstemon eatonii ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Penstemon eatonii

In research
Penstemon eatonii appears in biology research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry
Engineering practice reuses Penstemon eatonii in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom
Penstemon eatonii is common in secondary-school and first-year university syllabi. It links to neighbouring topics Flora of Colorado, Flora of Idaho, Flora of New Mexico, so understanding it makes those chapters shorter.
In everyday life
Look for Penstemon eatonii outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.
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How to study Penstemon eatonii in 20 minutes

  1. Read the reference excerpt below once, without taking notes.
  2. Close the page and write down what Penstemon eatonii means in your own words.
  3. Compare your version with the excerpt and mark what you missed.
  4. Work through the three examples above with pen and paper.
  5. Explain Penstemon eatonii out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Penstemon eatonii in simple terms?

Penstemon eatonii is a species of flowering plant in the genus Penstemon, known by the common name firecracker penstemon. It is native to the Western United States from Southern California to the Rocky Mountains.

Why does Penstemon eatonii matter?

Because it connects several biology ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Penstemon eatonii?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Penstemon eatonii.

Tags

  • Flora of Colorado
  • Flora of Idaho
  • Flora of New Mexico
  • Flora of Wyoming
  • Flora of the Southwestern United States
  • NatureServe secure species
  • Penstemon

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