Sunday, April 5, 2015

Western Wildflowers Rise for Easter

Long hairs on an unopened pasqueflower bud yesterday on the east front 
Pasqueflower is Montana's first dash of springtime color dotting the monochrome fields of winter. This lavender flower's early rise is nicely illustrated by a variety of cold-weather names and adaptations. By Easter this plant of many names can be found blooming along the lower slopes while snow still flies and melts intermittently.

In the mid-1700's Carl Linnaeus gave this plant the Latin name, "Anemone patens" from a specimen collected by English botanist William Hooker. Anemos is the Latin word for wind and patens means spreading. At about the same time another English botanist, Philip Miller, gave it the Latin name, "Pulsatilla patens." Pulsatilla is from the Latin word for pulsing or striking, which may have referred to blood from the sacrificial lambs of Passover. So his name might mean Passover flower struck (spread) by wind.

If you know any botanists, then you might not be surprised that names for this plant just kept sprouting. The German-American botanist Frederick Pursh studied a specimen of this plant that was collected by Lewis and Clark and, in 1814, named it "Clematis hirsutissima." Clematis is from the Greek word klema, which means to break off, possibly referring to the seeds breaking off in the wind. Hirsutissima is a Latin superlative meaning covered with hair. Thus, breaking off hairy plant.

Four years later, the English botanist Thomas Nuttall moved the genus back to Anemone and called this plant "Anemone ludoviciana," which means wind flower from the Louisiana Territory - that massive chunk of western land that included modern-day Montana. Swiss botanist Augustin Pyramus de Candolle soon changed the name to "Anemone Nuttalliana," or Nuttall's wind flower, and this was changed again in 1825 to Nuttall's pulsing flower, or "Pulsatilla Nuttalliana," by German botanist Christian Sprengel. In 1867, American botanist Asa Gray reclassified Hooker's original specimen as a distinct variety of this plant, naming it "Anemone patens var. Nuttalliana." Then in 1900 the American botanist Amos Arthur Heller switched the genus name again, to "Pulsatilla ludoviciana," or Louisiana Territory flower that blooms at Passover.

Modern analysis of our earliest spring wildflower sent us back to the start, but it hasn't ended the phylogenetic competition. In 1994 the Linnaean Plant Name Typification Project designated the name as "Anemone patens Linnaeus," and The Flora of North America (v. 3, 1997) claims that Linnaeus' designation is the correct name. But the 2011 North American Plant Atlas lists this plant as "Pulsatilla patens," claiming that this name super-cedes the one given by Linnaeus. Competing Latin names like these are sometimes referred to as scientific synonyms. So round and round we go, like winter into spring.

This plant also has many common names, including prairie crocus (it's not a crocus), prairie smoke, wind tulip and April fool. Blackfeet call it kippiaapi (related to kipitaaakii, or old woman, possibly because of the white hair of both). The first half of the name, pasqueflower, is from the Hebrew word, paschal, which means relating to Passover. This Easter's pasqueflower crop is starting to show up between lingering patches of winter snow and regular dustings by spring flurries. Yesterday I found a small number of starts and blooms on a few dry, rocky exposures along the east slope south of Saint Mary. The flowers were short and unopened, but that might just be because it was cloudy. Pasqueflowers close for the night and open for the sun, which they tend to follow across the sky like sunflowers. While open, the curved sepals reflect sunlight inward and raise the flower temperature by as much as 18F (10C), helping to speed up the development of pollen and seeds during springtime's cool temperatures.

Early-season shortness helps counter springtime winds, as does a covering of many hairs. Pasqueflower's hairy surface serves several other purposes as well. They're thought to be an irritant that discourages browsing by animals. The hairs also work as a thermal blanket in two ways. Frost forms out on the hairy tips, away from the more delicate plant parts. And the hairy surface also traps air like a down coat, creating a micro-climate that is slightly warmer that the surrounding air when the sun isn't shining.

As if irritating hairs weren't deterrent enough, pasqueflower foliage also contains a blistering agent that affects the mouth and intestinal linings (mucus membranes) of any mammal that tries to eat it. It's probably a good idea to have a double line of defense when you are the first green plant seen in spring by hungry herbivores. As the flowers mature, their styles elongate into 1.5" (3.8 cm) long plumes with a small seed on one end. While the flowers hug the ground, the plant stems elongate through spring to lift the feathery seeds of summer into the wind. A gusty "strike" sends the seeds on their way to start another generation of cold-weather flowers whose name varies, depending on who you ask and where you are.

Beyond the bloom: The Rural Municipality of Lansdowne, in Manitoba, is the proud home of the world's largest prairie crocus monument, located in Arden (population 150). Arden's tourism committee puts on a pasqueflower photography competition each spring, and you can see past winners here. There's also a native prairie grassland site north of Arden where thousands of native prairie crocuses bloom every April.