Flowering and fruiting heads of Polemonium eximium
Polemonium eximium, or showy sky pilot, is endemic to California; in the wild, this species only occurs at high elevations in the Sierra Nevada.
Forty percent of California’s 5500 native plant species occur only in the state. Unsurprisingly, perhaps, California has the most native species of all US states (see: Why California harbors so many plant species). The question surrounding what factors determine such high biodiversity in specific areas of the Earth is a longstanding one. In the linked article, the research results suggest that California is an important refuge for species (i.e., it is not that new species are evolving there at rates faster than elsewhere, but rather that old lineages are better able to persist due to factors such as a mountainous topography).
Polemonium eximium is a caespitose herbaceous perennial that reaches 10 to 40cm (4 to 15 in.) in height. Its hairy flowering stems culminate in a blue or purple inflorescence. The plant pictured above had one remaining stem in flower late in the summer, but more examples can be seen on the CalFlora page: Polemonium eximium. Individual flowers are in full bloom for only a matter of days through the short-lived growing season. These attract pollinators with a pungent scent, apparently reminiscent of urine.
The name sky pilot likely comes from the association with high altitudes. For most people, embarking on a trek through the mountains is the only way to see sky pilot, unless one is (or knows) an expert alpine gardener. Like many high-altitude plants, they are tricky to grow and persist in cultivation! The species typically grows on talus or rocky outcrops at 3000 to 4200m (~10500 to 13100 ft.). According to Wikipedia, you are most likely to find it on Mt. Whitney, Mt. Langley, or on Mt. Dana of Yosemite National Park. However, an interactive sightings map on Jepson eFlora notes other locations where occurrences have been documented. This scarcity makes it one of the most rewarding wildflowers to find throughout the Sierra Nevada. On a webpage devoted to exploring Yosemite National Park, someone makes mention of a pleasant encounter with sky pilots on the summit ridge of Mount Lyell, where hordes of butterflies were busy pollinating them and concurrently getting eaten by birds. Further noted was how the birds then excreted what they ate to fertilize this group of sky pilots, offering a glimpse into the life cycles of organisms in the High Sierra (linked page also has photos–click on the Image Gallery tab).
Most species of Polemonium are known by some common name variant of Jacob’s ladder. The much more widely-distributed Polemonium viscosum can also bear the common name of sky pilot, however.
I’ll add one little tidbit to what Dominic wrote above. If you are on Instagram, you can follow today’s photographer here:
https://www.instagram.com/damontighe/
It looks to me like Damon has just started a trip in Madagascar, so follow him for a glimpse into the nature from the part of the world (hopefully some of those pics find their way into his Flickr feed).
I am not a linguist of Greek and Latin. Would it be too cumbersome to provide a translation for the Latin or Greek name of the plants which this site so wonderfully presents? Pronunciation would also be a delight to hear. I think that I have sounded this one out, and it rings like a song in my ears.
According to the book “Stearn’s Dictionary of Plant Names For Gardeners”
Polemonium is: The Greek name, polemonion, originally applied to a medicinal plant associated with Polemon of Cappadocia. Jacob’s ladder is P. caeruleum.
eximuim: exi’mius,-a,-um Out of the ordinary; distinguished.
Thanks John T. Manion for the book 🙂
There’s almost too much to love here – a great photo, showing habitat and flower to nice effect, an interesting text, some fascinating links, and Daniel’s addendum. I like seeing the plant with most flowers gone over, and just one remaining in full bloom; it tells a lot and seems all the more real somehow. The article on California plant diversity is very interesting – I could hardly believe such a high percent of the state’s flora is endemic. The Yosemite website was fun to read, too. I’m not sure I’ll ever see this one in the wild at over 10,000 ft., so thank you!
According to BONAP’s Synthesis of the North American Flora, there are 5,701 native species in California of which 1,731 occur only in that state. This is 30% rather than the 40% stated above. Still an extremely high proportion of endemics. Thank you for your (as usual) excellent write-up and beautiful photo.
Polemonium eximium is an interesting species that I have done a bit of work with. Rather than smelling like urine, the plant smells VERY distinctively of skunk odor instead – this is a widespread smell common to many (all?) species in the genus. This plant is under extreme risk of extinction as climate change slowly erases our alpine flora. A very closely related species – Polemonium chartaceum – is found nearby in the Sweetwater and White mountains east of the Sierra crest. This species is much more rare than P. eximium, but is very much under the same climate change risk profile as P. eximium. A comprehensive survey of P. chartaceum is badly needed as it appears to be in steep decline in the Sweetwater Mountains and is most probably suffering the same fate in the White Mountains as well.
So glad this photo got picked up for this write up. Polemonium eximium is one of my favorite high sierra plants, because of its shear visual adacity to survive and flaunt it up at the high elevations. I first encountered the plant on the John Muir Trail back in 2003 when I saw it in bloom on Forester Pass and still get giddy each time I see it. Thank you Dominic for the great article and Daniel I will be getting some Madagascar plant images up on Flickr hopefully in the next month as I’m just starting the long journey home tomorrow. For now I have a stream of things flowing into iNaturalist but it’s all stuff off a cell phone.
Thanks Damon, looking forward to them!