Tuesday, December 30, 2008

Fictional botany: Conyza piscis

Hippie buttons (Conyza piscis), originally called georgeweed, is an upright-growing herbaceous biennial native to northwestern Australia. The leaves are digitate, with 7 to 15 needle-shaped leaflets. Leaflets are typically about 0.5 to 0.75 inches long (13-19 mm) and the upper surface is covered with downy grayish hairs. The first-year form is prostrate and inconspicuous; during the second year, the plant becomes a dense shrubby plant which may reach to 18 inches (46 cm) tall.

Flowers appear on racemes in late summer (February or March in the southern hemisphere; August or September in the northern) and are quite showy: the most typical wild form of the flower is approximately 1.5 inches (3.7 cm) in diameter, with 20-50 thin, narrow petals, striped in red and white, and a strong, jasminelike fragrance. There can be as many as 50 flowers per raceme, which frequently bends under the flowers' weight.

If successfully pollinated, the flowers become seed pods, which are woody, disc-shaped dark brown or black capsules about 1 inch (2.5 cm) in diameter, enclosed in stiff tan or greenish fibers. There are usually 8-14 seeds per capsule. Few animals can pry apart the fibers and remove the capsules, though a few birds and mammals in the plant's native range are strong enough to do so. Invariably, a few seeds escape as the capsule cracks open, which go on to produce the next crop.

The plant is sometimes deliberately planted as an ornamental, and there are a wide variety of cultivars available, with flowers of violet, red, orange, and yellow; however, crushed or bruised leaves have a strong rotten-fish odor (the botanical name piscis, meaning "fish," refers to this odor), particularly in young plants, which limits its usefulness as a garden plant. The odors of the cultivars 'Tie-Dye' (orange and yellow) and 'Age of Aquarius' (dark pink, unstriped) are said to be less intense and less objectionable; no doubt other reduced-odor cultivars will appear on the market very soon. Conyza does not appear to be invasive outside of its native range.

The origin of the first common name, georgeweed, is unknown. The name "hippie buttons" came into use in the 1960s and is both a reference to the seed pods (and particularly the "hemp-like" fibers covering them) and a reference to the plant's smell.

Conyza is of interest to industry as a possible renewable source for certain chemicals, particularly hexamethylenediamine and 1,4-diaminobenzene, which can be used to produce nylon, kevlar, and other synthetic fibers. These same molecules are also probably responsible its objectionable odor.

-from A Field Guide to Imaginary Plants (Mr. Subjunctive, ed.)


1 comment:

Lance said...

Hum, maybe because George smelled like fish?

You do have an imagination. :)