Ok, its Horseshoe again, for the last time (promise :)

Not since I last was in South Africa in 1993 have I seen so many different flowers in one small area. The snowlover, Chionophila jamesii, looks like a small white penstemon, and indeed is rarely found far from some snow lying around on the ground. I used a hat I borrowed from Panayoti to deal with the bright sun, but failed to use sunblock and got a really bad sunburn.  Its easy to forget in the cool mountain air just how intense the UV light is--at that altitude (we climbed to over 1300 feet) the air is thin and sunlight very intense. I found out what "Rocky Mountain High" really means when I got a touch of altitude sickness, first comes stomach discomfort, then one actually gets a bit loopy (probably from low oxygen levels, you can feel yourself thinking slower), and a light headache sometimes.  I was proud that I got to the top of our trail, while not the mountain peak it was damn close, and one could look over the continental divide to the watersheds that flow west.  I took the photo of Panayoti Kelaidis and Jan Fahls at the summit of our hike, and they took one of me as well.  Just before those photos, one can see a pink mound of Silene acaulis, which is yet another circumboreal tundra/alpine species.  It is quite common on the mountain, and some variation in shade of pink and floriferousness can be seen among the large populations of it. White daisies and pinnate foliage characterize Erigeron compositus.  Erigerons are generally easy to germinate and grow in rock gardens, and they are quite abundant and diverse in the montane West. One of a few alpine Trifolium species in the area, T. parryi is everywhere in the mountains west of Denver.  With its large trusses of purple flowers, its a serious improvement on our lawn clovers.  A yellow draba, which I dare not attempt to identify (the genus is a taxonomic nightmare with many similar species) thrusts its bright yellow flowers skyward, though at its size it doesn't get very far.  Androsace is a genus of often lovely plants, mainly Asian, but a tiny and rather insignificant one which might be A. septentrionalis (identifications are welcome) hides among the rocks in Colorado.  Rather more attractive in the horticultural sense is Eriogonum, possibly E. umbellatum, another diverse and confusing western American genus.  Both the silvery leaves and bright yellow flower umbels are easy on the eyes. In favored locations with some moisture Arnica cordifolia forms large patches of yellow daisies. The famous Colorado columbine, Aquilegia caerulea was only present near part of a nearby trail some of us took on the way down.  One can see why it has been brought into cultivation, the large blue and white flowers are quite nice. Finally a small Heuchera parvifolia hugs the light colored rocks it grows among. The foliage is quite attractive, though the greenish yellow flowers are more modest than some of its more showy cousins.
Hiking up Horseshoe Mountain with an enthusiastic and informed crew from the Denver Botanic Garden during what apparently was an optimal time during an exceptionally good flower year was an experience I will cherish for the rest of my life.  

And even more from Horseshoe

The white flowers of Dryas octopetala are a familiar sight in northern tundra and alpine areas and plenty of mats, some quite large, of it, were to be seen on Horseshoe.  An interesting fact about this plant is that it apparently is one of the plants that survived on often isolated mountaintops when the glaciers spread during the ice ages in the valleys below, despite what must have been fierce winter cold. Two primula species exist in the area, the smaller P. angustifolia and the larger P. parryi. Yet another northern genus that left a few representitives behind in North America when it was separated by tectonic activity and rising seas from Eurasia.  I was suprised to see Claytonia megarhiza in often wet areas, it looked best where there was plenty of water near it.  Some of these huge plants must be many decades old.  Lychnis apetala (or Silene uralensis) is a circumpolar species which  we found near the top of the mountain.  Its calyx is conspicously striped and inflated, the petals barely noticable. Papaver kluanense was rather scarce and only found near the top of the trail. The striking blue Mertensia is M. lanceolata. It is one of the larger plants in the upper part of the trail, with piercing blue flowers.   What looks like a refined sweet alyssum is Thlapsi montanum, sometimes called mountain candytuft with good reason.  Rhodiola (formerly Sedum) integrifolia does best in moist areas, and is widespread in the Colorado mountains.  Particularly nice red ones were seen on Horseshoe, though I saw some paler pink ones on Mt Evans later on. The prize of the hike, the focus of our search efforts, was the tiny blue Eritrichum nanum, a very diminuitive forget me not.  It has tiny fuzzy leaves and sky blue flowers.  I was especially proud to be the first in our very talented group to find it, even though I had only seen it in photographs before.  There may have been more of them in bloom earlier, we found several that were past flowering, not an easy task as they are even more inconspicuous without flowers.   This species only grows in the most desolate coldest upper reaches of the mountains in dry rocky areas.  There are many white flowered mat forming plants in these alpine reaches, and Arenaria is well represented.  This one might be A. obtusiloba.  The last pic shows Ranunculus eschscholtzii, another pretty alpine buttercup with rather large flowers.

Horseshoe Mountain continued....

 More beauties from Horseshoe as we climb higherm the  first photo shows a particularly nice form of Erigeron leiomerus with an extra row of rays.  The odd plant in the third photo is some kind of endemic to Horseshoe and perhaps another place or two, is Saussurea weberi.  This plant was in bud, bud later should open purplish flowers.  Aster (or Machaeranthera) coloradoensis is a rare species in general, and we didn't see many on Horseshoe, one of the handful of areas where this sprawling pink daisy is found.  Fortunately it is well established in cultivation as a rock garden plant.  Growing in shallow running water is Ranunculus adoensis.  I can imagine how difficult it would likely be to grow such a snowmelt plant of such a specialized habitat in cultivation.  Another rarity in nature, but not so hard to grow in rock gardens, is Townsendia montana.  It forms little bouquets of daisies which cover the foliage against the stark rocky substrate it grows in.  Senecio (or Ligularia) holmii forms attractive little clumps of leathery foliage and nodding yellow daisies.  Panayoti remarked how these resemble Cremanthodium from Asia, and I have to concur, they look very much like them and may even belong in the same genus. Its not too hard to visualize the genus stretched across the North American Eurasian landmass before the Bering strait formed ,isolating the ancestral stock to two distinct alpine locations, the Himalayas and the Rockies.  The bold yellow daisy known as Old Man of the Mountain, Hymenoxis (Tetraneuris) grandiflora is quite common in the Colorado mountains, and it was abundant on Horseshoe as well.  Phlox condensata is also common in the area, and on Horseshoe I found many flat rounded mats of it, most in full flower with five petalled white flowers.  Senecio (Packera) werneriaefolius var alpina is yet another one of the attractive yellow daisies of the high mountains, forming a low mat of tightly packed dark green foliage covered with numerous bright flowers.  In the last photo, a Frasera speciosa has finally reached maturity, shooting a meter high inflorescence packed with odd but pretty flowers, the culmination of several years of gathering and storing food for its final dramatic act of reproduction.