• Overcast
  • 63°
  • Comment

Mystery Plant

Posted: August 3, 2011 - 11:14pm

Here are two Mystery Plants at once. These two species will serve nicely for a consideration of what we call a “genus.”

The concept of the genus as a taxonomic category really came into play amongst botanists in the late 17th century. Briefly, a genus was recognized (and still is) as a convenient way to group closely related species. The dictionary definition of this word suggests “group” or “kind,” generally involving the notion of close relationships among its constituent members. Considered from the other perspective of grouping, a number of different but related genera (the plural of genus). Refrain from saying genuses. For instance, there are several species of sandspurs, and they all belong to the genus Cenchrus. Sandspurs are grasses, of course, and so are the various species of broom-straw, in the genus Andropogon. Sandspurs and broom-straws are related enough that both genera are placed together in the enormous grass family, this family known by the name Poaceae. (By the way, in print form, botanists italicize or underline the names of genera.)

Our two mystery plants both belong to the genus Hypericum, which contains about 40 different species found in North America. Hypericum is just one of the several genera placed in the Hypericaceae, or St. John’s Wort family. Various species of Hypericum may be stout and shrubby, or low and herbaceous, and with flowers bearing either four or five petals. Nevertheless, these species share enough features, especially those involving the flower parts and fruiting structures, that they are all considered at least reasonably close relatives. Some members of this genus have been highly prized for medicines; you have probably heard of the alleged anti-depressant qualities made from extracts from St. John’s Wort (the species named Hypericum perforatum), and other species are valued as ornamental plants. Still others are known as annoying weeds.

The big-flowered mystery plant, on the left in the photograph, is a shrub with bluish-green foliage, sometimes waist-high, with peeling bark, and native to high ground and cedar glades from Georgia and Tennessee into Pennsylvania, and into the Midwest and Texas. Its bright gold flower is really showy, and 400-500 stamens are commonly present, forming a conspicuous crown. This species is grown widely in cultivation, and sometimes escapes into surrounding countryside. Its small-flowered cousin, on the right, is an herb, mostly at home in damp places, and is fairly common from Quebec, Canada, to Florida, often in ditches or floodplain forests, or even in floating mats of vegetation on quiet lakes. Its comparatively humble flower features tiny petals, these somewhat copper-colored, with only about a dozen stamens present. Several differences exist between the two species, but they still have a lot in common.


Answer: On the left, “Blueleaf hypericum,” Hypericum frondosum. On the right, “Dwarf hypericum,” Hypericum mutilum

  • Comment


Spotted® - Bluffton

Beaufort County Jail Bookings

Get news delivered by e-mail!

Latest Updates